Rui Li - Soft-Switching Technology for Three-phase Power Electronics Converters

5 Chapter 5Figure 5.1 Circuit topology of the MVAC rectifier.Figure 5.2 Vector representation in complex plane with αβ coordina...Figure 5.3 Topology of the three‐phase converter.Figure 5.4 Sectors and voltage vectors in space complex plane.Figure 5.5 The voltage and current waveforms in a utility cycle.Figure 5.6 Sectors in space vector diagram.Figure 5.7 Three‐phase main bridges’ equivalent circuits of four vectors in ...Figure 5.8 The dendrogram analysis of switching commutation sequences betwee...Figure 5.9 The space vector sequence with one Type 2 commutation process. (a...Figure 5.10 Switching state of the MVAC circuit.Figure 5.11 Driving logic and key waveforms in Sector 1‐1.Figure 5.12 Equivalent circuit of stage 1: the initial stage.Figure 5.13 Equivalent circuit of stage 2: the first resonance stage.Figure 5.14 Equivalent circuit of stage 3: the freewheeling stage.Figure 5.15 Equivalent circuit of stage 4: the short‐circuit stage.Figure 5.16 Equivalent circuit of stage 5: the second resonance stage.Figure 5.17 Equivalent circuit of stage 6: the second steady stage.Figure 5.18 Equivalent circuit of stage 7: the Type 1 commutation stage.Figure 5.19 Equivalent circuit of stage 8: the third steady stage.Figure 5.20 Equivalent circuit of stage 9: the Type 1 commutation stage.Figure 5.21 Resonance circuit and its equivalent circuit of stage 2 ( t 1– t 2)....Figure 5.22 Equivalent circuit of stage 4 ( t 4– t 5). (a) Circuit state of the ...Figure 5.23 Short‐circuit duration ( t 4− t 3) vs. P 0.Figure 5.24 Driving logic waveform in sector 1‐1.Figure 5.25 The short‐circuit mode 1.Figure 5.26 The short‐circuit switches’ current. (a) Sector 1‐1. (b) Sector ...Figure 5.27 The short‐circuit mode 2.Figure 5.28 The short‐circuit switches’ current. (a) Sector 1‐1. (b) Sector ...Figure 5.29 The short‐circuit mode 3.Figure 5.30 The short‐circuit switches’ current.Figure 5.31 Control block diagram of the rectifier.Figure 5.32 Topology of the MVAC rectifier.Figure 5.33 The short‐circuit current i xvs. Zr .Figure 5.34 L r vers us Z r.Figure 5.35 CM200DU‐24NFH IGBT turn‐off loss under ZVS conditions.Figure 5.36 Recommended resonant parameters area.Figure 5.37 30 kW ZVS rectifier prototype.Figure 5.38 Bus bar and structure 30 kW ZVS rectifier prototype.Figure 5.39 Output current and grid voltage.Figure 5.40 The driving signal of main switches S 1and S 4.(a) Time: 2.5 ms/...Figure 5.41 v c1and i S1(time 5 μs/div).Figure 5.42 v c1and i S1(time 5 μs/div).Figure 5.43 v c7and i S7(time 10 μs/div).Figure 5.44 Current flowing L r( i Lr) and voltage across C cl( V cl). (a) Time:...Figure 5.45 Measured efficiency.

6 Chapter 6Figure 6.1 Topology of MVAC ZVS three‐phase inverter.Figure 6.2 Vector representation in complex plane with αβ coordina...Figure 6.3 Topology of the three‐phase inverter.Figure 6.4 Sectors and voltage vectors in space complex plane.Figure 6.5 The voltage and current waveforms in a utility cycle.Figure 6.6 Sectors in space vector diagram.Figure 6.7 Three‐phase main bridges’ equivalent circuits of four vectors in ...Figure 6.8 The dendrogram analysis of switching commutation sequences betwee...Figure 6.9 Three kinds of space vector sequences with one Type 2 commutation...Figure 6.10 Driving logic waveform in Sector 1‐1.Figure 6.11 Voltage and current waveforms, current polarity regions, and sec...Figure 6.12 Voltage and current waveforms, current polarity regions, and sec...Figure 6.13 Synthesis of v refin Sector 1‐1 when π/6 < φ < π/2.Figure 6.14 State transitions with preferred vector sequence in Sector 1‐1 w...Figure 6.15 Key waveforms in Sector 1‐1.Figure 6.16 Equivalent circuit of stage 1: stage.Figure 6.17 Equivalent circuit of stage 2: the first resonance stage.Figure 6.18 Equivalent circuit of stage 3: the diode freewheeling stage.Figure 6.19 Equivalent circuit of stage 4: the diode reverse recovery stage....Figure 6.20 Equivalent circuit of stage 5: the second resonance stage.Figure 6.21 Equivalent circuit of stage 6: stage.Figure 6.22 Equivalent circuit of stage 7: the first Type 1 commutation stag...Figure 6.23 Equivalent circuit of stage 8: stage.Figure 6.24 Equivalent circuit of stage 9: the second Type 1 commutation sta...Figure 6.25 Equivalent circuit of stage 2 ( t 1– t 2): the first resonance stage...Figure 6.26 Equivalent circuit of stage 5 ( t 4– t 5). (a) Circuit state of the ...Figure 6.27 Gate signal derivation in Sector 1‐1.Figure 6.28 Control block diagram of the MVAC inverter.Figure 6.29 Topology of the ZVS inverter.Figure 6.30 T r1versus resonant parameters.Figure 6.31 λ 7versus Z r..Figure 6.32 i res/ I mversus resonant impedance Z r..Figure 6.33 Resonant impedance Z rversus resonant parameters.Figure 6.34 CM200DU‐24NFH IGBT turn‐off loss under ZVS conditions.Figure 6.35 Recommended resonant parameters area.Figure 6.36 Experimental circuit.Figure 6.37 Output current and grid voltage.Figure 6.38 Voltage and current waveforms of the bridge switch.Figure 6.39 Voltage and current waveforms of the auxiliary switch.Figure 6.40 The resonant branch current and auxiliary switch voltage.Figure 6.41 Voltage across C Cland current through L r.Figure 6.42 Measured efficiency.

7 Chapter 7Figure 7.1 Topology of the CAC ZVS three‐phase inverter.Figure 7.2 Sectors of space vector diagram.Figure 7.3 Equivalent circuits of four vectors in sector 1‐1: (a) vector 111...Figure 7.4 Vector sequences with four vectors: starting with (a) 111, (b) 00...Figure 7.5 Vector sequences with two nonzero vectors and zero vector 000: st...Figure 7.6 Vector sequences with two nonzero vectors and zero vector 111: st...Figure 7.7 Driving sequence of ZVS‐SVM in sector 1‐1 within one switching pe...Figure 7.8 Key waveforms in sector 1‐1.Figure 7.9 Equivalent circuit of the first steady stage.Figure 7.10 Equivalent circuit of the first resonant stage.Figure 7.11 Equivalent circuit of diode freewheeling stage.Figure 7.12 Equivalent circuit of Type 2 commutation stage.Figure 7.13 Equivalent circuit of short-circuit stage.Figure 7.14 Equivalent circuit of the second resonant stage.Figure 7.15 Equivalent circuit of the second steady stage.Figure 7.16 Equivalent circuit of the first Type 1 commutation stage.Figure 7.17 Equivalent circuit of the third steady stage.Figure 7.18 Equivalent circuit of the second Type 1 commutation stage.Figure 7.19 Simplified equivalent circuit of the first resonant stage.Figure 7.20 Simplified equivalent circuit of the second resonant stage.Figure 7.21 Modification of short circuit pulse: (a) previous driving sequen...Figure 7.22 Driving sequences derivation: (a) sector 1‐1 and (b) sector 1‐2....Figure 7.23 Control block diagram of CAC ZVS three‐phase inverter.Figure 7.24 Turn‐off loss with paralleled buffer capacitor C b.Figure 7.25 Region for selecting resonant parameters.Figure 7.26 30 kW ZVS inverter prototype.Figure 7.27 Bus bar and structure 30 kW ZVS inverter prototype.Figure 7.28 Prototype of resonant inductor.Figure 7.29 Filter inductor.Figure 7.30 Experimental circuit.Figure 7.31 Output current and grid voltage.Figure 7.32 Voltage and current waveforms of the bridge switch.Figure 7.33 Voltage and current waveforms of the auxiliary switch.Figure 7.34 Voltage across C cland current through L r.Figure 7.35 Measured efficiency vs. output power.