A design technique of ARCP matrix converter using circuit simulator

1. A design technique of ARCP matrix converter using circuit simulator Nagasaki University Yuichiro Nakazawa

2. Contents Design and evaluation of ARCPMC prototype system ・　Introduction ・Power conversion system ・　Conventional voltage source inverter (VSI) topology ・　Matrix converter topology ・　ARCP matrix converter (ARCPMC) topology ・　Determination of specification & hardware parameters ・　Evaluation of design parameters ・　Outline of ARCPMC prototype system ・　Conclusion

3. Necessity of power conversion Now, disruption of environment such as global warming by energy consumption and exhaustion of energy resources are serious problem Energy saving technology is strongly demanded In the industry application, power conversion technology is effective for energy saving In the field of AC motor drive, inverter is widely used as AC adjustable speed drive ⇒Inverter can generate variable voltage and variable frequency 0000output from AC voltage source

4. AC DC AC Conventional VSI topology Converter circuit Inverter circuit Energy storage components ・ AC-DC-AC power conversion ・ Indirect power conversion device ・　Necessity of energy storage components

5. Conventional PWM Inverter Influence on Power Source ・　Influence on other devices by conductive noise ・Stress to power source by input current harmonics Influence on Power Converter ・　 Switching loss Influence on Motor ・　Insulation deterioration of motor winding by surge voltage ・Bearing degradation by high dv/dt of motor shaft voltage Conducted Emission Switching loss Motor Surge Voltage Power Converter Power Source Motor Input Current Harmonics Leakage Current Shaft Voltage Fig.1.Conventional PWM Inverter

6. Matrix converter topology AC AC ・ AC-AC direct power conversion ・ No large energy storage components ・ Regeneration ability & Displacement factor control ・ Reduced input harmonic current

7. Availability of soft switching technology Higher switching frequency for higher performance power conversion 　　　　･　Increasing of switching loss 　　　　･　Destruction of switching device by dv/dt or di/dt 　　　　･　Development of switching noise One of the solution of these problem ⇒The soft switching technology ZVS (zero voltage switching) , ZCS (zero current switching) One of the technique to realize soft switching ⇒ Auxiliary Resonant Commutated Pole ( ARCP ) technology Soft switching is realized by resonance using auxiliary circuit

8. Soft switching technology Matrix converter ARCP technology 　・　AC-AC direct power conversion 　・　No energy storage components 　・　Soft switching ・Reduced switching loss ARCP technology which is one the soft switching technology is applied to Matrix converter ARCP matrix converter

9. ARCP Matrix converter topology AC AC Main circuit Cr = Resonance Capacitor Input Filter Auxiliary circuit Lr = Resonance Inductor Composing of switch ( = Bi-directional switch) ・ Auxiliary switches & resonance components ・　Soft switching ( ZVS & ZCS ) ・ Reduced switching loss & switching noise & dv/dt, di/dt

10. A study purpose Design of ARCPMC prototype system Determination of hardware parameters and resonance components Hardware parameters and resonance components are determined, depend on evaluation system specification Evaluation of design parameters using circuit simulator Construction of ARCP prototype system

11. Control method The two-phase modulated PWM method • Base voltage (Vbase) is determined, according to the input three-phase voltage and output voltage command 2. Two other phases carry out PWM modulation Condition ① emid < 0 ・・・ Vbase= emax Condition ② emid > 0 ・・・ Vbase= emin Fig.2.The two-phase modulated PWM method

12. Control method The two-phase modulated PWM method • Base voltage (Vbase) is determined, according to the input three-phase voltage and output voltage command 2. Two other phases carry out PWM modulation Condition ① emid < 0 ・・・ Vbase= emax Condition ② emid > 0 ・・・ Vbase= emin Fig.3.The two-phase modulated PWM method

13. : Input current distribution factor Firing time In the switching period ( Ts ) Average of output voltage (S1) Average of output command voltage (S2) where Fig.4. firing time

14. ：　ARCP commutation ：　Capacitive commutation emax emid emin TC Commutation method ARCP commutation ARCP commutation realizes ZVS ( Zero Voltage Switching) by LC resonance Capacitive commutation Capacitive commutation realizes ZVS by charging and discharging action of resonance capacitor These commutation methods realize soft switching Fig.5. Commutation method

15. Switching pattern Fig.6. Switching pattern

16. Calculation equation Commutation time calculation equation e1 : Voltage before Commutation e2 : Voltage after Commutation

17. Specification of prototype system Specification of prototype system Resonance component parameters are decided from specification of prototype system and commutation time calculation equation which is shown in the preceding slide

18. Parameters of prototype system Specification of prototype system Parameters Input filter Lf = 0.18 [mH] Cf = 90 [mF] Resonant capacitor Cr = 50 [nF] Capacitive commutation time is set at 5msec or less, and ARCP commutation frequency is set at 200kHz to achieve in 20kHz switching frequency The resonant capacitor value is selected to change maximum commutation voltage within the selected capacitive commutation time for output current 10% of rated Resonant inductor Lr = 5 [mH] The inductance value of the resonant inductor is decided from the resonance frequency

19. System configuration Host PC Fig.7. System configuration of ARCPMC

20. System configuration Host PC ・ Calculation of firing time ・ Calculation of commutation time ・ Phase distinction DSP TMS320C31 Fig.8. System configuration of ARCPMC

21. System configuration Generation of PWM signal Host PC FPGA EPF10K50RC-240-4 Fig.9. System configuration of ARCPMC

22. Necessity of simulation Evaluation by experiment without simulation ・　Experiment environment and hardware conditions 000such as wiring impedance participate in a result・　Validation of software is difficult Evaluation by simulation Simulation model contains the control system which is equivalent to an experiment machine

23. Simulation model ARCPMC Model DSP&FPGA Model Fig.10. ARCPMC simulation model

24. Simulation model Main circuit Load DSP FPGA Input filter Auxiliary circuit Fig.11. ARCPMC simulation model

25. Simulation parameter The two-phase modulated PWM method

26. Simulation result The two-phase modulated PWM method Input lines voltage Vrs [500V/div] Input current Ir [50A/div] Output line voltages (Filtered) VUV [500V/div] Output current IU [10A/div] [20msec/div]

27. Simulation result The two-phase modulated PWM method Output phase voltage VU [500V/div] Output phase voltage VV [500V/div] Output line voltages VUV [500V/div] [2.5msec/div]

28. Prototype system Gate drive circuit Main circuit Resonance capacitor Resonance inductor IGBT switch Fig.12. ARCPMCprototype system

29. Prototype system Accurate resonance for ARCP commutation ・　The resonant circuit layout is decided to fix design layout00000000000 ・　A resonant path impedance each phase is equal000000000000000000000 Equivalent circuit

30. Conclusion Design of ARCPMC prototype system ・　Determination of specification and hardware parameters ・ Evaluation of design parameter using circuit simulator ・ Construction of prototype system Future development ・　Drive of ARCPMC prototype system

31. The END Thank you for your attention !! ARCP matrix converter