main switches S1 and S4. (a) Time: 2.5 ms/...Figure 5.41 v c1 and iS1 (time 5 μs/div).Figure 5.42 v c1 and iS1 (time 5 μs/div).Figure 5.43 v c7 and iS7 (time 10 μs/div).Figure 5.44 Current flowing Lr (iLr) and voltage across Ccl (Vcl). (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 vref in 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:
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 Cb.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 Ccl and current through Lr.Figure 7.35 Measured efficiency vs. output power.
8 Chapter 8Figure 8.1 Topology of the CAC ZVS three‐phase grid inverter.Figure 8.2 Sectors of space vector diagram.Figure 8.3 Key waveforms in sector 1‐1.Figure 8.4 Equivalent circuit of the first steady stage.Figure 8.5 Equivalent circuit of the first resonant stage.Figure 8.6 Equivalent circuit of the diode freewheeling stage.Figure 8.7 Equivalent circuit of the Type 2 commutation stage.Figure 8.8 Equivalent circuit of the short‐circuit stage.Figure 8.9 Equivalent circuit of the second resonant stage.Figure 8.10 Equivalent circuit of the second steady stage.Figure 8.11 Equivalent circuit of the first Type 1 commutation stage.Figure 8.12 Equivalent circuit of the third steady stage.Figure 8.13 Equivalent circuit of second Type 1 commutation stage.Figure 8.14 Demonstration of conduction loss models.Figure 8.15 Turn‐off loss measurement circuit and key waveforms.Figure 8.16 Fitted turn‐off loss function of device 1.Figure 8.17 Definitions of the unified inductor model.Figure 8.18 Measurement setup of magnetic core loss.Figure 8.19 Core losses per volume under different frequencies.Figure 8.20 Demonstration of the filter inductor.Figure 8.21 Average value of the volume over capacitance.Figure 8.22 Shape and dimensions of selected heat sink.Figure 8.23 Thermal model of the heat sink.Figure 8.24 3D model of the heat sink with IGBT devices.Figure 8.25 Procedures of optimization design.Figure 8.26 Optimization results of different switching modules.Figure 8.27 Prototype of the improved resonant inductor.Figure 8.28 Prototype of the improved filter inductor.Figure 8.29 Prototype of the improved clamping capacitor.Figure 8.30 Experimental circuit.Figure 8.31 Measured conversion efficiency.Figure 8.32 Measured efficiency and power density.
9 Chapter 9Figure 9.1 Current and voltage waveforms of the resonant inductor.Figure 9.2 Inductor with air gap.Figure 9.3 Equivalent magnetic circuit model.Figure 9.4 Window area Ae and cross‐section area Ac.Figure 9.5 Triangular inductor current.Figure 9.6 Design flowchart.Figure 9.7 EE55A shape size.Figure 9.8 Sinusoidal components of different frequencies.Figure 9.9 The barrel winding structure.Figure 9.10 Winding loss of different frequencies.Figure 9.11 The definition of the winding.Figure 9.12 Winding loss of each turn in the first order AC component.Figure 9.13 Distribution of winding loss and magnetic field lines.Figure 9.14 The position definition in the core window: (a) 0%; (b) 100%.Figure 9.15 Winding loss in different positions.Figure 9.16 Distribution of winding loss in different positions.Figure 9.17 Winding loss under different winding thickness.Figure 9.18 Distribution of winding loss under different winding thickness....Figure 9.19 Flat winding structure.Figure 9.20 Different structures: (a) structure 1: laminated structure; (b) ...Figure 9.21 Winding loss in different structures.Figure 9.22 Distribution of winding loss in the laminated structure.Figure 9.23 Distribution of winding loss in the interleaved structure.Figure 9.24 Distribution of winding loss and magnetic field lines.Figure 9.25 The position defined in the core window: (a) 0%; (b) 100%.Figure 9.26 Winding loss in different positions.Figure 9.27 Winding loss under different winding thicknesses.Figure 9.28 Distribution of winding loss under different winding thicknesses...Figure 9.29 Comparison of the different winding structures: (a) winding loss...Figure 9.30 Simulation results in a switching period.Figure 9.31 Structure of the resonant inductor.Figure 9.32 Experimental prototype of the resonant inductor.Figure 9.33 Voltage and current of the resonant inductor at 30
