Analysis and Design of Power Electronic Circuits Lab
Contents
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3. SWITCHED LOAD DRIVE Hr MAGNETICS BOARD 24 10Hz 1 10 DUTY ha DRIVE SWITCHING FREQUENCY ADJUSTMENT POTENTIOMETER DIN ON PWMTOTOP USEEXTERNAL SWITCHED UNUSED pour MOSFET PWM SIGNAL LOAD ACTIVE San SELECTION m m 10 EXTERNAL externa OLO gt an PWM INPUT OfO Ol OFF PWMTOBOT USEONBOARD SWITCHED DUTY CYCLE exe MOSFET PWM SIGNAL LOAD OFF POTENTIOMETER Figure 2 1 Schematic of Buck Converter 15 V2 Variable Power Resistor 2 2 Preparing the Setup Make the connections on the power pole board as shown in Fig 2 1 to use the upper MOSFET and the lower diode 2 3 2 4 2 5 Use the magnetics board BB board for the buck converter circuit The inductor is 100 wH Use a variable load resistor Rr as a load Use onboard PWM signals Connect the 12 signal supply at the DIN connector Signal supply switch S90 should be OFF Checks before powering the circuit Check the circuit connections as per the schematics Have your circuit checked by your Lab Instructor Powering the Circuit Switch ON the signal supply Check for green LED Adjust the duty ratio to 50 Adjust the switching frequency to 100kHz Apply input voltage V4 of 15 volts at terminals V1 and COM Measurement and Waveforms Take the following measurements 2 5 1 Varying Duty Ratio Set the duty ratio at 50 switching frequency at 100kHz and Rz 100 Vary the duty rat
4. TO BOT USEONBOARD SWITCHED DUTY CYCLE 105 LOADOFF POTENTIOMETER Figure 1 1 Block Diagram of Power pole Board Table 1 2 Test Point Details and Location on Power pole Board Test Point Description of Test Point Location 1 2 Terminal Terminal VI SY Fee Capacitor Oum dR C o estroma E E E H a a vsnu apen 20 62 80 31 0 N S 92191 N d 10 124 9 She 121 212 ane 43MOd 4256 NW HIMNO 122257 00 31105 OYOW S3NIYH 219 4 SWILSAS H3MOd 110925 OHIS 2 20 Figure 1 2 Power pole Board and current waveforms at the terminals of the MOSFETs and diodes can be observed Note Take care whenever you are using oscilloscope probes to measure voltage If the measure ment reference potential is different to the oscilloscope reference potential you must use differen tial probe To observe the voltage across the upper MOSFET e Connect the positive and negative terminals of a differential probe to the DRAIN and SOURCE of upper MOSFET To observe the upper MOSFET source current e Connect the positive and negative terminals of a differential probe to terminals CS2 and SOURCE D 2 in Fig 1 2 of upper MOSFET The current sense resistor value is 0 05 0 To observe the v
5. sponding duty cycle from the scope 9 3 3 Dynamic Performance of Closed Loop System e Ensure that the plug in board and the slope compensation jumper are plugged in e Set the duty cycle pot to minimum Switch on the main power supply and set it to 20 V e Switch on the signal power supply Slowly increase the reference voltage to 12 V by turning the duty cycle pot clockwise e Observe the output voltage V2 and the inductor current on the oscilloscope Store the waveform 9 4 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel is necessary e Plot the output voltage V and inductor current iz obtained in step 9 2 e What is the maximum duty ratio stable operation of the converter in step 9 3 1 Plot the inductor current waveform for stable and unstable operation e What is the maximum duty ratio stable operation of the converter in step 9 3 2 Plot the inductor current waveform for stable and unstable operation 48 Explain how slope compensation affects the range of duty cycle obtainable in constant fre quency peak current mode control Explain why in step 9 3 1 it is important to switch on the signal power supply after turning on the main power supply Plot the output voltage V waveforms and inductor current in closed loop operations with
6. 150pF 482k 820pF o MN IN 9 10 0k 52 1 OUT ot VREF 6 11 o MN o Figure 9 4 Type 2 Controller e Set the duty cycle pot to minimum e Switch ON the main power supply and set it to 25 V e Change the switch positions of the switch bank as shown in Fig 9 1 e Switch ON the signal power supply Ensure that main power supply is ON before signal power supply is switched ON e Observe the PWM and the inductor current waveforms e Slowly increase the reference voltage by turning the duty cycle pot clockwise Observe the point where the inductor current starts displaying oscillatory behavior Record the corre sponding duty cycle from the scope e Plug in the slope compensation jumper on to J61 T he slope compensation jumper circuit is shown in Fig 9 5 Observe how the inclusion of slope compensation affects the stability of the converter o AAA 46 9 09k 0 01uF Figure 9 5 Slope Compensation Jumper 47 9 3 2 Closed Loop Operation With Slope Compensation e Ensure that the plug in board and the slope compensation jumper are plugged in e Set the duty cycle pot to minimum e Switch ON the main power supply and set it to 15 V e Switch ON the signal power supply e Observe the PWM and the inductor current waveforms e Slowly increase the reference voltage by turning the duty cycle pot clockwise Observe the point where the inductor current starts displaying oscillatory behavior Record the corre
7. diode The voltage Table 1 1 Locations of components on Power pole Board No omponent Ref Des Location in Fig 1 2 Terminal V14 Terminal V24 3 Terminal COM input Terminal COM output IN connector for 12 V signal supply ignal supply switch ignal supply 12 fuse un ignal supply 12 V fuse ignal supply LED 10 Fault LED Over voltage LED BB o ver current LED 13 MOSFET diode and heat sink assembly Q15 D15 MOSFET diode and heat sink assembly n erminal for upper MOSFET source m o erminal for lower diode cathode erminal for upper diode anode 18 Screw terminal for lower MOSFET drain Screw terminal for Mid point 20 Magnetics Board plug in space 21 WM Controller UC3824 22 Duty ratio pot RV64 1 a Switching frequency adjustment pot RV60 24 External PWM signal input terminal Selector Switch Bank Daughter board connector Switched load 28 Resettable Fuse 29 Control selection jumpers 30 Ramp select jumper Current limit jumper J65 Small signal ac analysis selection jumper J64 Input current sensor LEM CS1 34 Output current sensor LEM CS5 SWITCHED LOAD BOARD SWITCHING FREQUEKCY ADJUSTMENT DIN on USE EXTERMAL SWITCHED UNUSED WOSFET LOAD ACTIVE SELECTION OSH cm pge IK PUT CONTROL wor P
8. is switched 6 5 4 Determining Efficiency e Switch the switched load OFF e Set the duty ratio to 40 e Measure the efficiency at switching frequency say 40kHz 60kHz 80kHz 100kHz 33 6 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel e Attach a graph of duty ratio versus output voltage V2 using data obtained in section 6 5 1 Also plot the theoretically estimated results on the same graph Compare the two plots Comment about how the converter works as a variable dc step down transformer e Using the waveforms obtained in section 6 5 2 explain the detailed per switching cycle rela tionship between the waveforms Explain why you have been asked to restrict the duty ratio to a maximum of 40 e Using the waveforms obtained in section 6 5 2 plot the primary and tertiary winding currents in transformer What is the effect of the inductor on the magnetics board Also explain the importance of having D3 on the magnetics board e Comment on the output voltage variation obtained in section 6 5 3 when there is a sudden load change e Plot the efficiency versus frequency using the data obtained in section 6 5 4 Comment on the results you obtain 34 Experiment 7 Switching Characteristic of MOSFET and Diode 7 1 Objective The objective of thi
9. voltage V1 ripple waveform e Calculate the peak peak input current ripple Repeat the above procedure for different switching frequencies say 40kHz 60kHz 80kHz 3 5 3 Varying Load e Set the duty ratio to 35 Rr 50Q and switching frequency to 100kHz e Keep increasing the load until the converter enters into the discontinuous conduction mode e Observe and make a copy of the input current to identify that the boost converter has gone into discontinuous conduction mode e Observe and make a copy of the voltage across MOSFET voltage waveform across diode Use differential probe 3 5 4 Determining Efficiency e Set the duty ratio to 50 e Adjust the load resistance so that load current is 0 4A e Measure the efficiency at switching frequencies of 40kHz 60kHz 80kHz 100kHz 3 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel is necessary 21 Attach a graph of duty ratio versus output voltage using the data obtained in section 3 5 1 Also plot the theoretically calculated results on the same graph Compare the two plots Comment about how the boost converter works as a variable dc step up transformer Plot the peak peak ripple in the output voltage versus switching frequency using the data obtained in section 3 5 2 Plot the theoretical res
10. Checks Before Powering The Circuit Check the circuit connections as per the schematic have your circuit checked by your Lab Instructor Powering the Circuit Switch ON the signal supply Check for green LED Adjust the duty ratio to 50 Set the switching frequencyof 100kHz Set Rz 500 Apply input voltage V4 of 15 volts Measurement and Waveforms Observe and make copy of the Drain Source voltage Vps using differential probe PWM signal and Anode Cathode voltage Vax of lower diode Observe and make a copy of the current through the upper MOSFET between CS2 and Source using a differential probe inductor current between CS5 and COM lower diode current between CS3 and Observe and make a copy of the Anode Cathode diode voltage Vax and diode current Adjust the time base to show the switching details during turn ON and turn OFF 36 4 Observe and make a copy of the Drian Source MOSFET voltage Vps and MOSFET current Adjust the time base to show the switching details during turn ON and turn OFF 7 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel necessary e Compare the switching waveform results obtained in step 1 of section 7 5 to the ideal voltage waveform e Compare the switching current waveforms obtained using st
11. ECE 445 Analysis and Design of Power Electronic Circuits Lab Old Diode and Thyristor based Experiments Before joined Majority of the experiments thyristor based obsolete Experiments do not reflect revised and modernized 445 curriculum No modern high speed switching circuits using MOSFETS or IGBTs Full bridge thyristor circuits do not work half split bridge configuration needs to be adopted Experiments are designed with focus on motor control There is a setup on cycloconverter which is hardly justified for basic 445 power electronics course Expensive and bulky New ECE 445 Power Pole Board Current measurement Fuses Fault Duty ratio External feedback Switching Protection control Control input load for transients warning Magnetic Boards Transformer Inductor Buck Boost Flyback Forward amp Buck boost Converter Converter Converter Experimental Setup leCr 500 MS s _Ascilloscope i Features of the Lab Module Modular laboratory setup PEBB Power Electronics Building Block Based on NSF initiative and multi university collaboration Cost effective and requires less space Trial runs for 2 semesters have yielded no safety problems so far Components supported by advanced SaberDesigner simulator models which students use for design and validation Onboard PWM signal Open loop and feedback control options Frequency analysis Eas
12. TMENT POTENTIOMETER DIN ON PWMTOTOP USEEXTERNAL SWITCHED UNUSED PME Sn MOSFET PWMSIGNAL LOAD ACTIVE CONTROL 0 100 external open CONTROL Ol 99 EXTERNAL PWM INPUT PWMTOBOT USEONBOARD SWITCHED DUTY CYCLE MOSFET PWMSIGNAL LOAD OFF POTENTIOMETER gt 12V Figure 3 1 Schematic of Boost Converter Confirm that you have connected the input and output terminals correctly to source and load as shown in Fig 3 1 Have your circuit checked by your Lab Instructor Powering the Circuit Switch ON the signal supply Check for green LED Set the duty ratio to its minimum Set Rz 500 Adjust the switching frequency to 100kHz Apply input voltage V4 of 10 volts at terminals V2 and COM Measurements Take the following measurements 3 5 1 Varying Duty Ratio Vary the duty ratio from minimum to 70 in steps of 10 20 e Measure the average DC load voltage V1 for the corresponding values of duty ratio e Calculate the theoretical average output voltage for the corresponding duty ratios e Compare the observed average output voltage results with the calculated ones 3 5 2 Varying Switching Frequency e Set the duty ratio to 50 switching frequency to 100kHz Rz 500 e Observe and make a copy of the input current 55 ripple waveform Observe and make a copy of the output
13. arization 1 11 Introduction The main feature of the Power pole Board is the reconfigurable power pole consisting of two MOS FETs and two diodes The drive circuits for the MOSFETs are incorporated on the board and so are the various protection circuits for over current and over voltage PWM signals to control the MOSFETs can be generated onboard or supplied from an external source The power pole can be configured to work in various topologies using three magnetics boards BB board for buck boost and buck boost converters Flyback board for flyback converter and Forward board for forward converter which plug into the Power pole Board In addition there is an option of doing fre quency analysis of each topology by injecting a small signal sinusoidal control voltage The board can also be operated in voltage current feedback mode using an external control circuit mounted on a daughter board which plugs into the Power pole Board board 1 2 Board Familiarization The basic block diagram of the Power pole Board is shown in Fig 1 1 and the actual board is shown in Fig 1 2 Please note that the location of the various components on the board are indicated in Table 1 1 1 2 1 Power pole The power pole consists of MOSFETs 010 and Q15 and diodes D10 and D15 The source of the upper MOSFET and the drain of the lower MOSFET are connected to screw terminals for external connection and so are the anode of upper diode and the cathode of the lower
14. ching transients as the load is switched vols 8 4 Preparing the Setup for finding as e Turn OFF the supply voltage Vj the signal supply and remove the jumper J64 G 5 in Fig 1 2 e Switch the switched load OFF as shown in Fig 8 1 e Connect the function generator output to J64 please confirm the polarity of connector e Adjust the function generator voltage v to 200mV peak peak and 50Hz sinusoidal output 40 e Keep the variable power resistor at 10Q and duty ratio at 50 e Have your circuit checked bu your Lab Instructor e Turn ON the 12V signal supply and check for green LED e Apply Va 24V 8 5 Finding Transfer Function Set the scope to AC coupling to measure the output voltage V2 ripple e Measure the magnitude ratio of V2 and v and phase difference between them e Repeat the above procedure for different frequencies of v from 50Hz to 10kHz 8 6 Type 3 Voltage Controller Once you get the transfer function or the Bode plot of the buck converter you can design a Type 3 voltage controller The Type 3 voltage control board has the schematic as shown in Fig 8 3 C2 VREF Figure 8 3 Voltage Controller Plug in Board The values of the resistors and capacitors of the voltage control board are given in Table 8 1 e Reference value Vr amp r can be set using the duty ratio pot e Reference value can t be set below 10V e For the pin details of te
15. current sense resistor for each MOSFET see locations C 3 and C 5 in Fig 1 2 The voltage across these sense resistors can be observed using test points provided on the board To see the upper MOSFET current e Connect the positive and negative terminals of a differential probe to CS2 and SOURCE of upper MOSFET To see the lower MOSFET current e Connect an oscilloscope probe to CS3 and its ground to SOURCE of lower MOSFET Note The lower diode current can also be observed using test point 259 However the upper diode current cannot be observed 1 2 8 PWM Signal Generation PWM signals required for the MOSFETs can be generated using the on board PWM controller UC3824 1 5 in Fig 1 2 There is also an option to supply PWM signals from an external source To use the onboard PWM e Put switch 2 of the selector switch bank 530 E 5 in Fig 1 2 to its bottom position PWM INT To use external PWM e Put switch 2 of the selector switch bank S30 to its top position PWM EXT 12 e Connect the external PWM signal to the terminal J68 G 6 in Fig 1 2 While using the onboard PWM for operation of the power pole in open loop the duty ratio can be controlled using pot RV64 F 5 in Fig 1 2 The duty ratio can be varied from 4 to 98 The frequency of the PWM can be adjusted using the trim pot RV60 I 5 in Fig 1 2 There is a provision for providing an external ramp to the UC3824 IC This is useful for peak current m
16. d Drives to design a type 3 voltage mode controller for the buck converter L 1004H C 690uF 0 10 fs 100k Hz V4 42V and the duty ratio is set to 50 The phase margin of the open loop transfer function should 60 at 1kHz Note that these are the same specifications for the voltage mode control you used in section 8 7 43 44 Experiment 9 Peak Current Mode Control 9 1 Objective In this experiment we will be using a plug in board to accomplish peak current mode control for a buck boost converter First the aspects of constant frequency peak current mode control will be explored Then the plugin board will be used to achieve feedback voltage control of the converter The goal is to understand how to design a peak current mode controller with voltage feedback DRIVE E ZN a CIRCUIT Variable Power Resistor INDUCTOR BOARD SWITCHED LOAD le DRIVE 2 MAGNETICS BOARD CIRCUIT 10 Hz 10 DUTY al DRIVE SWITCHING FREQUENCY ADJUSTMENT POTENTIOMETER DIN ON PWMTOTOP USE EXTERNAL SWITCHED UNUSED MOSFET PWM SIGNAL LOAD ACTIVE 50 SELECTION 12 0 100 EXTERNAL So PWM INPUT externa O O a
17. ep 2 of section 7 5 to the ideal current waveform e Using the waveforms obtained in step 3 of section 7 5 calculate the conduction and switching losses of the Diode e Using the waveforms obtained in step 4 of section 7 5 calculate the conduction and switching losses of the MOSFET e Using the values of conduction and switching losses of the MOSFET and Diode obtained in the above steps estimate the efficiency of the converter Compare the estimated efficiency with the efficiency obtained for the buck converter the Buck Converter Experiment What could be the reasons for the difference in values if any 37 38 Experiment 8 Voltage Mode Control 8 1 Objective The objective of this experiment is to design a controller to operate the buck converter in voltage control mode For this experiment a plug in daughter board will be used to accomplish the control objective The small signal transfer function d s is a small signal perturbation in the duty cycle and v s is the corresponding variation in the output voltage must first be obtained for the buck converter The plug in daughter board is used to implement the voltage mode control feedback with the required open loop gain LEM sone Lee Ou LEM CIRCUIT R m MID PONT INDUCTOR BOARD
18. et the switching to 100kHz e Set the duty ratio to its minimum e Set Rr 100 e Apply input voltage V4 of 15 V at the terminals V1 and COM 6 5 Measurements Take following measurements 6 5 1 Varying Duty Ratio e Vary duty ratio from minimum to 40 in steps of 10 e Measure the average output voltage V2 for the corresponding values of duty ratio e Calculate the theoretical average output voltage for the corresponding duty ratios e Compare the observed average output voltage results with the calculated ones 32 6 5 2 Constant Duty Ratio e Set the duty ratio to 40 switching frequency to 100kHz Rz 100 e Observe and make a copy of the primary side voltage of the transformer Use a differential probe to measure the voltage Store the waveforms e Observe and make a copy of the input current CS1 output current CS5 and MOSFET current CS3 6 5 3 Switched Load Active PWM TO USE EXTERNAL SWITCHED UNUSED MOSFET PWM SIGNAL LOAD ACTIVE m PWM TO BOT USE ONBOARD SWITCHED MOSFET PWM SIGNAL LOAD OFF Figure 6 2 Switch Position for Forward Converter using Switched Load e Set the duty ratio to 4096 e Set the switching frequency to 100kHz e Switch ON the switched load to the active position using the selector switch bank as shown in Fig 6 2 e Observe and make a copy of the output voltage V2 waveform Adjust the timebase to show the details of the switching transients as the load
19. ews gt Me 1 E D pe m IN De E CN u LT 8 Interface M FPGA Board b Motor Set Student Access to Modern Technology Makes a Difference UNDERGRADUATE STUDENTS 08 Duheric Acharya Burra Huang 5 Pradhan UIC stood 1 among U S Universities and 314 in world ranking the 2005 IEEE Future Energy Challenge Competition Fuel Cell Inverter 5 w s 3 21 H 254 EJ 14 5 E d A T 1 2 re 4 EIE 1 gt A i as sa ala de pr 744 ba ee 2 x fee ps en CMM Filter Inductors ors ECE 445 Power Pole Board Current measurement SCHOTT POWER Fuses Fault Duty ratio External feedback Switching protection control control input load for transients warning safety Issues Setup is done before powering anything up Probe connections can be done before powering things up Laboratory manual clearly outlines the safety issues to the students and safety precautions that need to be taken Input voltage lt 40 V maximum operating current less than 5A High and low voltage logic areas are separate e What more can we do Clearly tell the 445 students the nature of the experiments at the beginning of the course Suggestion by Univ of Minnesota Take a safety test following NCF formerly MAL approach Transparent enclosure UL a
20. he Setup Make the connections on the power pole board as shown in Fig 6 1 to use the lower MOSFET e Use the Forward magnetics board e Use a variable load resistor as a load e Connect the 12V signal supply to the DIN connector Signal supply switch 590 should be OFF 6 3 Checks before powering the circuit e Check the circuit connections as per Fig 6 1 e Confirm that you have selected the lower MOSFET e Have your circuit checked by your Lab Instructor 31 DRIVE CIRCUIT DRIVE He CIRCUIT Di Vie ZN ZN T n TRANSFQRMER BOAR com CN jd MAGNETICS BOARD SWITCHED LOAD 10Hz I 10 DUTY I DRIVE PWMTOTOP USE EXTERNAL DIN ON MOSFET PWM SIGNAL SWITCHED LOAD ACTIVE UNUSED J 12 gt 12 USE ONBOARD MOSFET SWITCHED OAD PWM SIGNAL OFF 0 100 DUTY CYCLE POTENTIOMETER EXTERNAL PWM INPUT OO o WITCHING FREQUENCY ADJUSTMENT POTENTIOMETER PWM IC CONTROL SELECTION olo EXTERNAL CONTROL O OO OPEN LOOP Figure 6 1 Schematic of Forward Converter 6 4 Power Circuit e Switch ON the signal supply Check for green LED e S
21. in Fig 1 2 and its ground to COM D 1 in Fig 1 2 For output voltage measurement e Connect the oscilloscope probe to test point V2 K 1 in Fig 1 2 and its ground to COM L 1 in Fig 1 2 1 2 6 Current Measurement LEM current sensors B 1 K 2 in Fig 1 2 are provided to measure the input and output currents The input current sensor is located after the input filter capacitor and the output current sensor is located before the output filter capacitor Calibration of the current sensors is such that for 1A current flowing through each the output is 0 5 V These signals are amplified by a factor of 2 and are brought out to the daughter board connector J60 for use in feedback current control Currents through the MOSFETs and output capacitor are measured using current sense resistors Refer to Table 1 2 for details of the various current measurement test points To measure input current e Connect oscilloscope probe to CS1 1 in Fig 1 2 and its ground to COM D 1 in Fig 1 2 To measure output current 11 e Connect oscilloscope probe to CS5 K 2 in Fig 1 2 and its ground to COM L 1 in Fig 12 To measure output capacitor ripple current e Connect oscilloscope probe to CS4 K 3 in Fig 1 2 and its ground to COM The current sense resistor value is 0 1 0 1 2 7 MOSFET Drive Circuit The power pole MOSFETs are driven by high side drivers IR2127 These drivers have in built overcurrent protection using a
22. io from 10 to 90 in steps of 10 Measure the average output voltage for the corresponding duty ratio 16 e Calculate the theoretical average output voltage for the corresponding duty ratios e Observe and make a copy of the output ripple voltage inductor current and capacitor current waveforms 2 5 2 Varying Switching Frequency e Set the duty ratio to 50 e Measure the peak peak output ripple voltage e Observe and make copy of the inductor current CS5 and capacitor current CS4 wave forms e Repeat the above procedure for different switching frequencies 40kHz 60kHz 80kHz Make sure that output voltage V2 is maintained at 7 5V 2 5 3 Varying Load e Set the switching frequency at 100k H z and duty ratio at 50 e Set the load resistance Rr 10 0 e Add some extra load and observe and make a copy of the inductor current waveform e Keep increasing the load until the buck converter enters discontinuous current mode op eration Note down the average inductor current value when the converter starts entering discontinuous current mode of operation e Observe and make a copy of the output voltage voltage across the MOSFET and diode 2 5 4 Determining Efficiency Determine the efficiency of the buck converter at frequencies of 40k Hz 60kHz 80kHz and 100k H 2 e Set duty ratio at 50 e Set load resistance Rr 10 e Measure the average output current 10 e Measure the average input curre
23. is necessary 25 Attach a graph of duty ratio versus output voltage CS5 using the data obtained in section 4 5 1 Also plot the theoretically calculated results on the same graph Compare the two plots Comment about how the buck boost converter works as a variable dc step down or step up transformer Attach a copy of the inductor current CS5 waveform obtained in section 4 5 2 Plot the ex perimental and theoretically estimated ripple current waveforms on the same graph Compare the two graphs and comment Plot the efficiency versus frequency using the data obtained in section 4 5 4 Comment on the results you obtain Compare and comment on the efficiencies obtained in the buck boost and buck boost con verters 26 Experiment 5 Flyback Converter 5 1 Objective The objective of this experiment is to study the characteristics of the flyback converter using the power pole board in open loop control mode Our main goal is to compare the theoretical results with the experimental results 5 2 Preparing the Setup Make the connections on the power pole board as shown in Fig 5 1 to use the lower MOSFET e Use the Flyback magnetics board The turns ratio is 1 1 e Use a variable load resistor as a load e Connect the 12V signal supply to the DIN connector Signal supply switch 590 should be OFF 5 3 Checks before Powering the Circuit e Check the circuit connections as per the schematic e Check that the lowe
24. l TP24 N SyNC DIS DCP01212P T 0 a amp Lp ey OVERVOLT 015 5 a8 015 5 1 vcc J N gt on Sla amp 2 Le redd T gt eh ee OUT 4 E 3 N m D oar 3 ERR 6 1 n x cs R16 5 gt 4 5 NN tHOR AIR R2127 S Q UP 1 0K L 2 amp o 5 gt L 5 2 25 a S 2 2K S30 A o nk KUR IN PWM oie ERROR 4 TP18 EOT u R31 pn m 2 m 12V 5 5 R10 4 P 2 2 RR mo 930 amp 8 al 4 9 eo p ranw 5342 o ATO 10 9 9 9 99 9 am PN2222A 1 1 919 010 M2 M 5 6 M7 yg vB a HS1 HS2 5 l 2 Ex 1 Is inre 5 5190 5190 ERR 6 4 2 x CS R13 on 4 5 4 IR2127 VS 1 0K Bot E 0 N 319 a zeg L S45 5 2 26 S 504 4 4 4 4 allt 11 Title Power Pole Board Size Number Rev D Date 07 02 2002 Drawn by Filename PPlab_ rev2 SCH Sheet 1 of 2 B C D E F G H
25. mes to zero Switch of all the power supplies and remove the power supply connections Let the load be connected at the output for some time so that it helps to discharge capacitor or inductor if any completely Precautions while modifying the circuit Switch Off the circuit as per the steps in section 3 5 Modify the connections as per your requirement Again check the circuit as per steps in section 3 3 and switch ON as per steps in section 3 4 Other Precautions No loose wires or metal pieces should be lying on table or near the circuit to cause shorts and sparking Avoid using long wires that may get in your way while making adjustments or changing leads Keep high voltage parts and connections out of the way from accidental touching and from any contacts to test equipment or any parts connected to other voltage levels When working with inductive circuits reduce voltages or currents to near zero before switch ing open the circuits BE AWARE of bracelets rings metal watch bands and loose necklace if you are wearing any of them they conduct electricity and can cause burns Do not wear them near an energized circuit Learn CPR and keep up to date Your can save a life When working with energized circuits while operating switches adjusting controls adjusting test equipment use only one hand while keeping the rest of your body away from conducting surfaces Experiment 1 Power pole Board Famili
26. n OFF PWMTOBOT USEONBOARD SWITCHED DUTY CYCLE 60 CONTROL 10 MOSFET PWM SIGNAL LOAD OFF POTENTIOMETER Figure 9 1 Current Mode Controller Schematic 45 9 2 Preparing setup for Open Loop Operation e Reconstruct the buck boost converter used in Expt 3 as in Fig 9 1 e Turn on the signal power supply and set the switching frequency to 100 kHz and duty cycle such that output voltage V 12 V e Change the switch positions of the switch bank as shown in Fig 9 2 e Set to 20 V and the variable power resistor to 20 PWM TO USE EXTERNAL SWITCHED UNUSED MOSFET PWM SIGNAL LOAD ACTIVE PWM BOT USE ONBOARD SWITCHED MOSFET PWM SIGNAL LOAD OFF Figure 9 2 Switch Position for Switched Load 9 2 1 Measurements e Observe the output voltage V2 and inductor current on the oscilloscope e Store the waveform 9 3 Preparing setup for closed loop operation and measurements 9 3 1 Closed Loop Operation Without Slope Compensation e Setup the control selection as in Fig 9 3 EXTERNAL OPEN CONTROL O LOOP O Figure 9 3 Switch Position for Closed Loop Operation 46 e Remove shorting link from J61 and insert the Type 2 Controller plug in board whose circuit is shown in Fig 9 4 into the terminal strip J60 The pin numbers shown in the figure correspond to pin numbers on the terminal strip This board will add the voltage feedback to the control
27. nt J e Measure the average output voltage V2 17 e Measure the average input voltage Vj e Calculate the efficiency of the buck converter for different frequencies using the above mea surements 2 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel is necessary e Attach a graph of duty ratio versus output voltage V2 using data obtained in section 2 5 1 Also plot the theoretically calculated results on the same graph Compare the two plots and comment about how the buck converter works as a variable dc step down transformer e Plot the peak peak ripple in the output voltage versus switching frequency using data obtained in section 2 5 2 Plot the theoretical results on the same graph Compare the two plots Comment on why you were asked to maintain the average output voltage constant e Attach a copy of the inductor current CS5 and capacitor current C54 waveforms obtained in section 2 5 2 Explain the relation between the two currents e Attach a copy of the output voltage and inductor current waveforms obtained in section 2 5 3 Compare with the theoretically estimated waveforms e Plot efficiency versus frequency using the data obtained in section 2 5 4 Comment on the results you obtain 18 Experiment 3 Boost Converter 3 1 Objec
28. ode control For this remove jumper J61 H 5 in Fig 1 2 and use the RAMP pin on daughter board connector J60 1 2 9 Frequency Analysis Frequency analysis of any converter built using the power pole can be done by injecting a low voltage sinusoidal signal at jumper J64 G 5 in Fig 1 2 To do this e Remove jumper J64 e Connect the small signal sinusoidal source at the jumper terminal J64 Note J64 is to be shorted in all other modes of operation 1 2 10 Power pole Board in Feedback Control Mode The power pole board can be operated in either open or closed loop and is selected by jumpers J62 and J63 J 5 in Fig 1 2 For open loop operation e Keep J62 and J63 in the righthand positions Closed loop operation will be described in the relevant experiment 13 14 Experiment 2 Buck Converter 2 1 Objective The objective of this experiment is to study the characteristics of a simple buck converter The circuit will be operated under continuous current mode CCM and open loop conditions no feedback Our main goal will be to compare the theoretical results with the experimental results LEM Vis LEM DRIVE CIRCUIT V2 Vit gt va e INDUCTOR BOARD
29. of current in the inductances For example a boost converter can have an output voltage that can theoretically go to infinite values if it is operating without load Moreover the currents in portions of some converter circuits may be many times larger than the currents supplied by the dc supplies powering the converter circuits A simple buck converter is an example of a power electronics circuit in which the output current may be much larger than the dc supply current 2 Potential problems presented by Power Electronic circuits e Electrical shock may take a life e Exploding components especially electrolytic capacitors and arcing circuits can cause blind ness and severe burns e Burning components and arcing can lead to fire 3 Safety precautions to minimize these hazards 3 1 General Precautions e carm and relaxed while working in Lab 3 2 3 3 3 4 When working with voltages over 40V or with currents over 10A there must be at least two people in the lab at all times Keep the work area neat and clean No paper lying on table or nearby circuits Always wear safety glasses when working with the circuit at high power or high voltage Use rubber floor mats if available to insulate yourself from ground when working in the Lab Be sure about the locations of fire extinguishers and first aid kits in lab A switch should be included in each supply circuit so that when opened these switches will de energize
30. of duty ratio e Calculate the average theoretical DC output voltage for the corresponding duty ratios e Compare the observed average output voltage results with the calculated ones 4 5 2 Varying Switching Frequency e Set the duty ratio to 50 switching frequency to 100kHz Rz 500 e Observe and make the copy of the inductor current CS5 ripple waveform e Observe and make the copy of the output voltage V2 ripple waveform e Calculate the peak peak inductor current ripple e Repeat the above procedure for different switching frequencies say 40kHz 60kHz 80kHz 4 5 3 Varying Load e Set the duty ratio to 50 Rr 500 and switching frequency to 100kHz e Keep increasing the load until the converter enters into the discontinuous conduction mode e Observe and make a copy of the inductor current C S5 to identify that the buck boost con verter has gone into discontinuous conduction mode e Observe and make a copy of the voltage across MOSFET Use differential probe voltage waveform across diode 4 5 4 Determining Efficiency e Set the duty ratio to 50 e Adjust the load resistance so that load current is 0 25A e Measure the efficiency at switching frequencies of 40kHz 60kHz 80kHz 100kHz 4 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel
31. oltage across the lower MOSFET e Connect an oscilloscope probe to the DRAIN and its ground to the SOURCE E 4 in Fig 1 2 of the lower MOSFET To observe the lower MOSFET source current e Connect an oscilloscope probe to terminal CS3 and its ground to the SOURCE E 4 in Fig 1 2 of the lower MOSFET The current sense resistor value is 0 05 2 The same test points also measure the lower diode current if that is included in the circuit To observe the voltage across the upper diode e Connect the positive and negative terminals of a differential probe to termianl CATH and ANODE E 2 in Fig 1 2 of the upper diode To observe the voltage across the lower diode e Connect an oscilloscope probe to CATH LOW and its ground to the ANODE of the lower diode D 4 in Fig 1 2 1 2 2 Magnetics Boards To build various converters using the Power pole Board three plug in boards are provided 1 BB Board Fig 1 3 a For buck boost and buck boost converters 2 Flyback Board Fig 1 3 b For flyback converter 3 Forward Board Fig 1 3 c For forward converter How to use these boards will be described in the subsequent experiments Flyback a BB Board b Flyback Board c Forward Board Figure 1 3 Magnetics Boards 1 2 3 Signal Supply 12 volts signal supply is required for the MOSFET drive circuits and also the measurement and protection circuits This is obtained from a wall mounted isolated power supply which
32. output voltage feedback step 9 3 3 Comment on the effect of peak current controller on the operation of converter 49 APPENDIX The detailed circuit of the the power pole is attached It consists of two sheets 50 B C D E F G H D2 zb sci 1N4004 css gt b z ma ouma OUTA Sy JN 4 lINB OUTB 3 4 ling 2 2 ne J20 Ne v2 21 21 J2 lt vn gt NG 12 12V INE INE 3 kx 3 75A c1 v SEL 8 8 TU Hpo oH 2 2 x vs OT v ET y J18 2 MAGBOARD E ek 924 cst MEA S x gy NEG 2 NEG N P AAS LA 25 cs z LA 25 NP M OAD OR gO1 SIE 1 N gt R23 n NSS h DRIVE LOAD se 12V 12 9 12 1 0K IRFP450 U1 J22 412V ISO 412v GND iSo GND 22
33. plugs into the DIN connector J90 A 5 in Fig 1 2 Switch 590 B 6 in Fig 1 2 controls the signal power to the board Each time a fault occurs turn off and turn on this switch to reset the board The green LED D99 B 5 in Fig 1 2 indicates if the 12 V signal supply is available to the board Fuses F90 B 5 in Fig 1 2 and F95 B 6 in Fig 1 2 provide protection for the 12 V and 12 V supplies respectively 1 2 4 Load Any external load is to be connected across terminals V2 and COM L 1 and L 6 in Fig 1 2 An onboard switched load is provided to facilitate the observation of the transient response of any converter built using the power pole Thus it is possible to periodically switch in and out a 20 Q load K 4 to K 6 in Fig 1 2 The frequency and duty ratio of this load is fixed at 10 Hz and 1096 To select the switched load 10 e Put switch 3 of selector switch bank 30 E 5 in Fig 1 2 to the top position Load SW ON In order to observe the switched load current e Connect the positive and negative terminals of a differential probe to CS LOAD 1 and CS LOAD 2 L 5 in Fig 1 2 This measures the voltage across the 20 resistor e Switched load current is the measured voltage divided by 20 1 2 5 Input Output Voltage Measurement Test points for input output voltage measurements are provided on the Power pole Board For input voltage measurement e Connect the oscilloscope probe to test point 1 C 1
34. pproved power equipments may cost a bit more Need your inputs and help ECE 445 Power Electronics Laboratory User Manual Contents 1 Power pole Board Familiarization 2 Buck Converter 3 Boost Converter 4 Buck Boost Converter 5 Flyback Converter 6 Forward Converter 7 Switching Characteristic of MOSFET and Diode 8 Voltage Mode Control 9 Peak Current Mode Control ii 15 19 23 27 31 35 39 45 iv SAFETY PRECAUTIONS 1 Why is safety important Attention and adherence to safety considerations is even more important in a power electronics laboratory than its required in any other undergraduate electrical engineering laboratories Power electronic circuits can involve voltages of several hundred volts and currents of several tens of amperes By comparison the voltages in all other teaching laboratories rarely exceed 20V and the currents hardly ever exceed a few hundred milliamps In order to minimize the potential hazards we will use dc power supplies that never exceed voltages above 40 50V and will have maximum current ratings of 20A or less Most of the time we will use supplies of 20V or less and 1 A or less output current capability However in spite of this precaution power electronics circuits on which the student will work may involve substantially larger voltages up to hundreds of volts due to the presence of large inductances in the circuits and the rapid switching on and off of amperes
35. r MOSFET has been selected e Have your circuit checked by your Lab Instructor 27 DRIVE CIRCUIT 3 gt b gt as AZ MID POINT FLYBACK COUPLED INDUCTOR BOARD DRIVE Has MAGNETICS BOARD CIRCUIT 10Hz 10 DUTY DRIVE N SWITCHED LOAD o SWITCHING FREQUENCY ADJUSTMENT POTENTIOMETER DIN ON PUNTO USE EXTERNAL SWITCHED UNUSED EM PWMSIGNAL LOAD ACTI Jna lu m m m Do 190 EXTERNAL externa O O Ol open 12V PWM INPUT CONTROL O O O LOOP DUTY CYCLE POTENTIOMETER OF RUM TOE BOT USE ONBOARD SWITCHED MOSFE LOAD OFF Figure 5 1 Schematic of Flyback Converter 5 4 Powering the Circuit e Switch ON the signal supply Check for green LED e Set the switching frequency to 100kHz and the duty ratio to 50 e Set Ry 300 e Apply input voltage V4 of 15V at terminal V1 and COM 5 5 Measurements Take the following measurement 5 5 1 Varying Duty Ratio Vary the duty ratio from 0 to 60 in steps of 10 e Measure the average output voltage V2 for the corresponding values of duty ratios e Calculate the theoretical average output voltage value for the corresponding duty ratios Compa
36. re the observed average output voltage results with the calculated ones 28 5 5 2 Constant Duty Ratio e Set the duty ratio to 50 switching frequency to 100kHz e Using differential probe observe and make a copy of the voltage across the primary side of the coupling inductor e Observe and make the copy of the voltage across the secondary side of the coupling inductor e Observe and make the copy of the input current CS1 and output current CS5 5 5 3 Switched Load Active e Set the duty ratio to 50 Set the switching frequency to 100kHz Switch ON the switched load to the active position using the selector switch bank as shown in Fig 5 2 e Observe and make a copy of the output voltage V2 waveform Adjust the time base to show the details of switching transients as the load is switched PWM TO USE EXTERNAL SWITCHED UNUSED MOSFET PWM SIGNAL LOAD ACTIVE C m PWM TO BOT USE ONBOARD SWITCHED MOSFET PWM SIGNAL LOAD OFF Figure 5 2 Switch Positions for Flyback Converter controller with switched load 5 5 4 Determining Efficiency e Switch the switched load OFF e Keep the duty ratio constant at 50 e Adjust the load resistance so that load current is A e Measure the efficiency at the switching frequencies of 40kHz 60kHz 80kHz 100kHz 29 5 6 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consi
37. rminal strip J60 please refer the schematic of the power pole board Al 100kQ 20 6650 25 19n F 2 5976n F 4 7191n F Table 8 1 Voltage Control Board Compenent Values EXTERNAL OPEN CONTROL LOOP Figure 8 4 Control selection for Voltage Mode Control plug in board 8 7 Prepa ring the Setup for Voltage Mode Control Operation e Set the control selection jumpers J2 and J3 J 5 in Fig 1 2 as shown in Fig 8 4 e Remove the function generator and insert the jumper J64 e Insert the Voltage Mode Control plug in board in the terminal strip 60 e Keep Rz 100 e Switch ON the switched load to the active position using the selector switch bank as shown in Fig 8 2 e Turn ON 4 e Have your 12V signal supply and check for green LED circuit checked by your Lab Instructor e Set V4 to 24V e Use the du ty cycle pot RV64 to set V2 to 12V 8 8 Measurements in Voltage Mode Control Operation Observe and make a copy of the output voltage V2 8 9 Lab Report The lab report should have a brief abstract detailing what has been done in the experiment The remaining part of the report should consist of the information asked below along with any discussion you feel is necessary e Construct the bode plot of the small signal transfer function of the converter from the results obtained in section 8 5 e Use the K factor method described in chapter 4 of a First Course on Power Electronics an
38. s experiment is to study the switching characteristics of power MOSFETs and power diodes using a buck converter The circuit will be operated in open loop conditions no feedback Our main goal is to understand the switching behavior of these two power devices LEM As LEM DRIVE i5 CIRCUIT V2 V2 1 Vi Variable SE a Power Resistor INDUCTOR BOARD COM SWITCHED LOAD DRIVE MAGNETICS BOARD ZN 10 Hz 10 DUTY S DRIVE SWITCHING FREQUENCY ADJUSTMENT POTENTIOMETER DIN ON PWMTOTOP USEEXTERNAL SWITCHED UNUSED a i MOSFET PWM SIGNAL LOAD ACTIVE Jav SELECTION m m vs 1006 EXTERNAL externa OLO gt av PWM INPUT CONTROL OfO Ol OFF PWMTOBOT USE ONBOARD SWITCHED DUTY CYCLE MOSFET PWM SIGNAL LOAD OFF POTENTIOMETER Figure 7 1 Schematic of Buck Converter 35 7 2 Preparing the Setup Construct the buck converter circuit as shown in Fig 7 1 to use the upper MOSFET and lower diode 7 3 7 4 7 5 Use the BB magnetics board board The inductor is 100 Use a variable load resistor as a load Connect 12V the signal supply to the DIN connector Signal supply switch 90 should be OFF
39. st of the information asked below along with any discussion you feel is necessary e Attach a graph of duty ratio versus output voltage V2 using data obtained in section 5 5 1 Also plot the theoretically calculated results on the same graph Compare the two plots and comment about how the flyback converter works as either a step down or step up transformer e Using the waveforms obtained in section 5 5 2 explain the relationship between the primary and secondary voltages of the coupled inductor e Using the current waveforms obtained in section 5 5 2 estimate the magnetizing current for the coupled inductor Compare the output inductor current CS5 waveforms with the output current waveform for the buck converter obtained in BUCK CONVERTER EXPER IMENT What s the effect of this current on the output voltage ripple e Using the waveforms obtained in section 5 5 3 comment on the output voltage variation due to the effect of the switched load What could be done to overcome this problem e Plot the efficiency versus frequency using the data obtained in section 5 5 4 Comment on the results you obtain 30 Experiment 6 Forward Converter 6 1 Objective The objective of this experiment is to study the characteristics of the forward converter The forward converter will be operated in open loop mode no feedback Our main goal is to compare the theoretical results with the experimental results 6 2 Preparing t
40. the entire setup Place these switches so that you can reach them quickly in case of emergency and without reaching across hot or high voltage components Precautions to be taken when preparing a circuit Use only isolated power sources either isolated power supplies or AC power through isolation power transformers This helps using a grounded oscilloscope and reduces the possibility of risk of completing a circuit through your body or destroying the test equipment Precautions to be taken before powering the circuit Check for all the connections of the circuit and scope connections before powering the circuit to avoid shorting or any ground looping that may lead to electrical shocks or damage of equipment Check any connections for shorting two different voltage levels Check if you have connected load at the output Double check your wiring and circuit connections It is a good idea to use a point to point wiring diagram to review when making these checks Precautions while switching ON the circuit Apply low voltages or low power to check proper functionality of circuits Once functionality is proven increase voltages or power stopping at frequent levels to check for proper functioning of circuit or for any components is hot or for any electrical noise that can affect the circuit s operation 3 5 3 6 3 7 Precautions while switching off or shuting down the circuit Reduce the voltage or power slowly till it co
41. tive The objective of this experiment is to study the characteristics of a simple boost converter The circuit will be operated under CCM and openloop condition Our main goal is to compare the theoretical results with the experimental results Note It is important that care is taken while doing the boost converter experiment using the power pole board The input and output terminals in the case of the boost converter are interchanged as compared to that of the buck converter V2 amp COM is the input and V1 amp COM is the output 3 2 Preparing the Setup Make the connections of the power pole board as shown in Fig 3 1 to use the lower MOSFET amd the upper diode e Use the BB magnetics board for the boost circuit The inductor is 100 e Use a variable load resistor as a load e Connect the 12 signal supply to the DIN connector Signal supply switch 590 should be OFF 3 3 Checks before powering the circuit e Check the circuit connections as per the schematics 19 3 4 3 5 LEM d DRIVE 4 CIRCUIT MS ver var amp 1 Ia m Variable l Power Resistor INDUCTOR BOARD Q SWITCHED LOAD MAGNETICS BOARD Qv LEM DRIVE CIRCUIT 10Hz 10 DUTY DRIVE SWITCHING FREQUENC ADJUS
42. uit connections as shown in Fig 4 1 23 4 4 4 5 DRIVE CIRCUIT 3 INDUCTOR BOARD amp SWITCHED LOAD 212 Hat MAGNETICS BOARD CIRCUIT 10Hz 10 DUTY DRIVE SWITCHING FREQUENCY ADJUSTMENT POTENTIOMETER DIN PWMTOTOP USEEXTERNAL SWITCHED UNUSED or AN MOSFET PWM SIGNAL LOAD ACTIVE ae 12V 1005 EXTERNAL externa open gt 12 PWM INPUT CONTROL O fO LOOP OFF PWMTOBOT USEONBOARD SWITCHED DUTY CYCLE Go MOSFET PWMSIGNAL LOAD OFF POTENTIOMETER Figure 4 1 Schematic of Buck Boost Converter Confirm that you have connected the input and output terminals correctly to source and load as shown in Fig 4 1 Have your circuit checked by your Lab Instructor Powering the Circuit Switch ON the signal supply Check for green LED Set the duty ratio to its minimum Set Rz 500 Adjust the switching frequency to 100kHz Apply input voltage V4 of 10 volts at the terminals V1 and 2 Measurements Take the following measurements 4 5 1 Varying Duty Ratio e Vary the duty ratio from minimum to 7096 in steps of 1096 24 e Measure the average DC load voltage V2 for the corresponding values
43. ults on the same graph Compare the two graphs and comment Attach a copy of the inductor current CS5 waveform obtained in section 3 5 2 Plot the experimental and theoretically estimated input ripple current on the same graph Compare the two graphs and comment Plot efficiency versus frequency using the data obtained in section 3 5 4 Comment on the results you obtain Compare and comment on the efficiencies of the buck converter obtained in Experiment 2 and the boost converter 22 Experiment 4 Buck Boost Converter 4 1 Objective The objective of the experiment is to study the characteristics of the simple buck boost converter The circuit will be operated under CCM and openloop conditions Our main goal is to compare the theoretical results with the experimental results Note It is important that care is taken while doing the buck boost converter ex periment using the power pole board The input and output terminals in the case of the buck boost converter are different as compared to that of the buck or boost converters 4 2 Preparing the Setup Make the connections for the power pole board as shown in Fig 4 1 e Use the BB magnetics board for the buck boost converter circuit The inductor value is 100 uH e Use a variable load resistor as a load e Connect the 12 signal supply to the DIN connector Signal supply switch 90 should be OFF 4 3 Checks before powering the circuit e Check the circ
44. x E E 5 i L 55 of U40 B x 5 7 wo lt N Sty D LM393ANE 12V sinh 278 gis x 12V 10 0K L a gt ls 7 J90 Sr le 1 5 CURRENT2 2 1 m bal 5 x o N 2 5 LM6172 CS2 3 2 bo Ao o gt 5 8 zk 8 5 S 3 2 uy 6 0 25 co tT l C78 12V I DINS F95 DPDT Eu ak s Sls 0 25 A 942 aA N SHB 470 Oy U50 ad 2 R78 R77 x vec t t 10 0K 10 0K est RESET S30 C TS gt R52 S THR our 3 12 005 t DRIVE_ LOAD amp CONT 12V 9 7 pis 11 5 o5 C77 1 2M Sale 1 loo nn 4077 1N4148 LM555CNB CURRENT1 1 3 LM6172 Et 581 _ N D52 2 0 gt as amp C79 Title Power Pole Board Size Number D Date 07 02 2002 Drawn by Filename PPlab_ rev2 SCH Sheet 2 A B D E F G H
45. y setup and configuration changes Safe banana plugs for input and output connections Maximum input voltage 40 V DC Maximum operating current 5 DC New G UG National Science Foundation Proposition Master Controller _ a 2 DC a Eee I 6 AC DC DC AC AC DC pc ac Bt AC Power Power a n Module 3 DC AC B AC 0 t Module 1 e b a DC a DSP Slave DC 2 AC DC DC AC 57 r Controller 1 AC DC DC AC B ac Sensor Ze 2 DG Signals E b iE b TT ac m 5 15 AC DC DC AC 9 d DC AC c AC DC DC u d a Remote DC DC AC 5 Signals 4 0 D en Module wer Bj ji Senso FH Signals DSP Slave 1 Gate un Controller Signals gt 0 920 3c 3300 Communication interface Power Power N Module 4 odule From Master Controller Preliminary Discrete Setup with Support from Altera Texas Instruments FPGA based Motor Drive Laboratory Setup Lane 6 OV d E n
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