A control method of a hybrid active third harmonic injection rectifier circuit

Abstract

The application relates to a control method of a hybrid active third harmonic injection rectifier circuit, the hybrid active third harmonic injection rectifier circuit comprising a three-phase uncontrolled rectification bridge, a three-way bidirectional switch module, a main switch module and a first main power inductor. The main switch module comprises a first main switch tube and a second main switch tube, the first main switch tube and the second main switch tube work in a low-loss working mode and a CCM working mode based on a first main control signal and a second main control signal respectively, so that the switch tube can reduce switching loss, reduce electromagnetic interference and improve circuit reliability in different working modes.

Description

Technical Field

[0001] This invention relates to the field of charging modules, and more specifically, to a control method for a hybrid active third harmonic injection rectifier circuit. Background Technology

[0002] With the rapid development of battery charging technology, hybrid active third harmonic injection rectifier circuits are increasingly being used in charging modules. Existing hybrid active third harmonic injection rectifier circuits generally include a three-phase uncontrolled rectifier bridge, a three-way bidirectional switching module, a main power inductor, and a main switching module. For the switching transistors in the three-way bidirectional switching module, low-frequency control is generally used, with a frequency twice the input frequency, and each cycle contains two 60° conduction cycles. For the switching transistors in the main switching module, high-frequency control is generally used, i.e., frequencies above tens of kHz, and the main power inductor operates in CCM mode. The simulation waveforms of the control strategies of existing hybrid active third harmonic injection rectifier circuits are shown below. Figure 1 As shown. Because the switching transistors in the main switching module operate in a hard-switching state throughout the entire process and at a high frequency, their switching losses are relatively large, resulting in serious electromagnetic interference problems and affecting circuit reliability. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a control method for a hybrid active third harmonic injection rectifier circuit, which reduces switching losses, reduces electromagnetic interference, and improves circuit reliability, in order to address the above-mentioned deficiencies of the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problem is: a control method for constructing a hybrid active third harmonic injection rectifier circuit, wherein the hybrid active third harmonic injection rectifier circuit includes a three-phase uncontrolled rectifier bridge, a three-way bidirectional switch module, a main switch module, and a first main power inductor; The first input terminal of the three-phase uncontrolled rectifier bridge is connected to the first phase power supply and the first input terminal of the three-way bidirectional switch module; the second input terminal of the three-phase uncontrolled rectifier bridge is connected to the second phase power supply and the second input terminal of the three-way bidirectional switch module; the third input terminal of the three-phase uncontrolled rectifier bridge is connected to the third phase power supply and the third input terminal of the three-way bidirectional switch module; the first output terminal of the three-phase uncontrolled rectifier bridge is connected to the positive bus, and the second output terminal is connected to the negative bus. The output terminal of the three-way bidirectional switch module is connected to the first terminal of the first main power inductor and the first terminal of the second main power inductor. The second terminal of the first main power inductor is connected to the first terminal of the main switch module. The second terminal of the main switch module is connected to the positive bus and the third terminal is connected to the negative bus. The main switch module includes a first main switch transistor and a second main switch transistor; the control terminal of the first main switch transistor receives a first main control signal and the control terminal of the second main switch transistor receives a second main control signal; the first terminal of the first main switch transistor is connected to the positive bus, the second terminal is connected to the second terminal of the second main switch transistor, and the first terminal of the second main switch transistor is connected to the negative bus. The first main switch and the second main switch operate in low-loss mode and CCM mode respectively based on the first main control signal and the second main control signal.

[0005] In the control method of the hybrid active third harmonic injection rectifier circuit of the present invention, the main switch module further includes a third main switch and a fourth main switch; the hybrid active third harmonic injection rectifier circuit further includes a second main power inductor. The control terminal of the third main switch receives the third main control signal, the control terminal of the fourth main switch receives the fourth main control signal, the first terminal of the third main switch is connected to the positive bus, the second terminal is connected to the second terminal of the fourth main switch, and the first terminal of the fourth main switch is connected to the negative bus. The first end of the second main power inductor is connected to the output end of the three-way bidirectional switch module, and the second end is connected to the second end of the third main switch and the second end of the fourth main switch. The first main switch, the second main switch, the third main switch, and the fourth main switch operate in low-loss mode and CCM mode respectively based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal; or The first main switch, the second main switch, the third main switch, and the fourth main switch operate in low-loss mode and multi-channel interleaving mode respectively based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal.

[0006] In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, the first main control signal satisfies: T+= (upos + 2uneg) / (upos) uneg); The second main control signal satisfies: T- = (upos + 2uneg) / (upos) uneg); Wherein, T+ represents the first main control signal, T- represents the second main control signal; upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage; The third main control signal has the same waveform as the first main control signal and the transmission time is staggered by the first phase; the fourth main control signal has the same waveform as the second main control signal and the transmission time is staggered by the first phase.

[0007] In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, the low-loss operating mode includes the DCM+QR mode; in the DCM+QR mode, the first main switch, the second main switch, the third main switch and the fourth main switch are turned on for a first time based on the first main control signal, the second main control signal, the third main control signal and the fourth main control signal respectively, and the inductance current of the first main power inductor and the second main power inductor rises; The first main switch, the second main switch, the third main switch, and the fourth main switch are then turned off for a second time based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal, respectively. During this second time, the inductance currents of the first main power inductor and the second main power inductor decrease. When the inductance currents drop to zero, the parallel capacitors of the first and second main switches resonate with the first main power inductor for a first resonant time, and the parallel capacitors of the third and fourth main switches resonate with the second main power inductor for a first resonant time. Then, the turn-on signal for the next cycle arrives. The first resonance time is n*Ts+1 / 2Ts, where n is a positive integer and Ts is the resonance period.

[0008] In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, in CMM mode, when the first main switch, the second main switch, the third main switch and the fourth main switch are turned on for a first time based on the first main control signal, the second main control signal, the third main control signal and the fourth main control signal respectively, the inductance current of the first main power inductor and the second main power inductor rises. The first main switch, the second main switch, the third main switch, and the fourth main switch are then disconnected for a second time based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal, respectively. The inductor current of the first main power inductor and the second main power inductor decreases. Before the inductor current decreases to 0, the turn-on signal of the next cycle arrives. In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, in the multi-interleaved mode, the waveform of the third main control signal is the same as that of the first main control signal and the wave emission time phase is interleaved by 180°; the waveform of the fourth main control signal is the same as that of the second main control signal and the wave emission time phase is interleaved by 180°.

[0009] In the control method of the hybrid active third harmonic injection rectifier circuit of the present invention, the hybrid active third harmonic injection rectifier circuit further includes a first freewheeling module and a second freewheeling module. The first freewheeling module includes a first freewheeling capacitor and a first freewheeling diode, and the second freewheeling module includes a second freewheeling capacitor and a second freewheeling diode; The positive terminal of the first freewheeling capacitor is connected to the positive busbar, and the negative terminal is connected to the first end of the first main power inductor. The cathode of the first freewheeling diode is connected to the positive busbar, and the anode is connected to the first end of the first main power inductor. The negative terminal of the second freewheeling capacitor is connected to the negative busbar, and the positive terminal is connected to the first terminal of the second main power inductor. The anode of the second freewheeling diode is connected to the negative busbar, and the cathode is connected to the first terminal of the second main power inductor.

[0010] In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, the three-phase uncontrolled rectifier bridge includes a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a fifth rectifier diode, and a sixth rectifier diode. The anode of the first rectifier diode is connected to the cathode of the second rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fifth rectifier diode is connected to the cathode of the sixth rectifier diode, the cathode of the first rectifier diode is connected to the cathodes of the third and fifth rectifier diodes, and the anode of the second rectifier diode is connected to the anodes of the fourth and sixth rectifier diodes.

[0011] In the control method of the hybrid active third harmonic injection rectifier circuit described in this invention, the three-way bidirectional switching module includes a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a fifth switching transistor, and a sixth switching transistor. The control terminals of the first and second switching transistors receive a first control signal; The control terminals of the second and fourth switching transistors receive the second control signal; The control terminals of the fifth and sixth switching transistors receive a third control signal; The first end of the first switching transistor is connected to the first input terminal of the three-way bidirectional switch module, the first end of the third switching transistor is connected to the second input terminal of the three-way bidirectional switch module, and the first end of the fifth switching transistor is connected to the third input terminal of the three-way bidirectional switch module. The second end of the first switch is connected to the second end of the second switch, the second end of the third switch is connected to the second end of the fourth switch, the second end of the fifth switch is connected to the second end of the sixth switch, and the first ends of the second switch, the fourth switch, and the sixth switch are connected to the output end of the three-way bidirectional switch module.

[0012] In the control method of the hybrid active third harmonic injection rectifier circuit of the present invention, the hybrid active third harmonic injection rectifier circuit further includes an input filter. The first input terminal, the second input terminal, and the third input terminal of the input filter are respectively connected to the first phase power supply, the second phase power supply, and the third phase power supply; the first output terminal, the second output terminal, and the third output terminal of the input filter are respectively connected to the first input terminal, the second input terminal, and the third input terminal of the three-phase uncontrolled rectifier bridge.

[0013] The present invention provides a control method for a hybrid active third harmonic injection rectifier circuit, wherein the hybrid active third harmonic injection rectifier circuit includes a three-phase uncontrolled rectifier bridge, a three-way bidirectional switch module, a main switch module, and a first main power inductor; the first input terminal of the three-phase uncontrolled rectifier bridge is connected to a first-phase power supply and the first input terminal of the three-way bidirectional switch module; the second input terminal of the three-phase uncontrolled rectifier bridge is connected to a second-phase power supply and the second input terminal of the three-way bidirectional switch module; the third input terminal of the three-phase uncontrolled rectifier bridge is connected to a third-phase power supply and the third input terminal of the three-way bidirectional switch module; the first output terminal of the three-phase uncontrolled rectifier bridge is connected to a positive bus, and the second output terminal is connected to a negative bus; the output terminal of the three-way bidirectional switch module is connected to the first terminal of the first main power inductor and the first terminal of the second main power inductor, wherein the first main power inductor... The second terminal is connected to the first terminal of the main switching module, the second terminal of the main switching module is connected to the positive bus, and the third terminal is connected to the negative bus. The main switching module includes a first main switching transistor and a second main switching transistor. The control terminal of the first main switching transistor receives a first main control signal, and the control terminal of the second main switching transistor receives a second main control signal. The first terminal of the first main switching transistor is connected to the positive bus, the second terminal is connected to the second terminal of the second main switching transistor, and the first terminal of the second main switching transistor is connected to the negative bus. The first main switching transistor and the second main switching transistor operate in a low-loss operating mode and a CCM operating mode, respectively, based on the first main control signal and the second main control signal. In different operating modes, the first main switching transistor and the second main switching transistor can reduce switching losses, reduce electromagnetic interference problems, and improve circuit reliability. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 The waveform diagram is a simulation of the existing hybrid active third harmonic injection rectifier circuit. Figure 2A This is a schematic block diagram of a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention; Figure 2B This is a schematic block diagram of a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention; Figure 3 This is a circuit schematic diagram of a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention; Figure 4 yes Figure 3 The simulation diagram of the DCM+QR operating mode of the hybrid active third harmonic injection rectifier circuit is shown. Figure 5 yes Figure 3 The simulation diagram of the CMM operating mode of the hybrid active third harmonic injection rectifier circuit shown is shown. Figure 6 yes Figure 3 The waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit are shown. Figure 7 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit in CMM operating mode. Figure 8 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit in DCM+QR operating mode. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0016] Figure 2A This is a schematic block diagram of a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention. (See diagram below.) Figure 2AAs shown, the hybrid active third harmonic injection rectifier circuit of the present invention includes a three-phase uncontrolled rectifier bridge 10, a three-way bidirectional switch module 20, a main switch module 30, a first main power inductor L1, a first freewheeling module 40, and a second freewheeling module 50. The first input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the first phase power supply and the first input terminal of the three-way bidirectional switch module 20; the second input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the second phase power supply and the second input terminal of the three-way bidirectional switch module 20; the third input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the third phase power supply and the third input terminal of the three-way bidirectional switch module 20; the first output terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the positive bus, and the second output terminal is connected to the negative bus; the first freewheeling module 400 is connected between the positive bus and the first terminal of the first main power inductor L1; the second freewheeling module 500 is connected between the negative bus BUS- and the first terminal of the second main power inductor L2. The output terminal of the three-way bidirectional switch module 20 is connected to the first terminal of the first main power inductor L1, the second terminal of the first main power inductor L1 is connected to the first terminal of the main switch module 30, the second terminal of the main switch module 30 is connected to the positive bus, and the third terminal is connected to the negative bus. The main switch module 30 includes a first main switch and a second main switch; the control terminal of the first main switch receives a first main control signal, and the control terminal of the second main switch receives a second main control signal; the first terminal of the first main switch is connected to the positive bus, the second terminal is connected to the second terminal of the second main switch, and the first terminal of the second main switch is connected to the negative bus. The first main switch and the second main switch operate in low-loss mode and CCM mode respectively based on the first main control signal and the second main control signal.

[0017] In a preferred embodiment of the present invention, the first main control signal satisfies: T+= (upos + 2uneg) / (upos) The second main control signal satisfies: T- = (upos + 2uneg) / (upos) (uneg); where T+ represents the first main control signal, T- represents the second main control signal; upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage. Under different operating modes, the first and second main switches can reduce switching losses, mitigate electromagnetic interference, and improve circuit reliability.

[0018] Figure 2B This is a block diagram illustrating a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention. Figure 2BAs shown, the hybrid active third harmonic injection rectifier circuit of the present invention includes a three-phase uncontrolled rectifier bridge 10, a three-way bidirectional switch module 20, a main switch module 30, a first main power inductor L1 and a second main power inductor L2, a first freewheeling module 40 and a second freewheeling module 50.

[0019] The first input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the first phase power supply and the first input terminal of the three-way bidirectional switch module 20; the second input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the second phase power supply and the second input terminal of the three-way bidirectional switch module 20; the third input terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the third phase power supply and the third input terminal of the three-way bidirectional switch module 20; the first output terminal of the three-phase uncontrolled rectifier bridge 10 is connected to the positive bus and the second output terminal is connected to the negative bus; the first freewheeling module 400 is connected between the positive bus and the first terminal of the first main power inductor L1; the second freewheeling module 500 is connected between the negative bus BUS- and the first terminal of the second main power inductor L2. The output terminal of the three-way bidirectional switch module 20 is connected to the first terminal of the first main power inductor L1 and the first terminal of the second main power inductor L2. The second terminal of the first main power inductor L1 is connected to the first terminal of the main switch module. The second terminal of the main switch module 30 is connected to the positive bus and the third terminal is connected to the negative bus. The second terminal of the second main power inductor L2 is connected to the fourth terminal of the main switch module.

[0020] The main switch module 30 includes a first main switch transistor, a second main switch transistor, a third main switch transistor, and a fourth main switch transistor. The control terminal of the first main switch transistor receives a first main control signal, the control terminal of the second main switch transistor receives a second main control signal, the control terminal of the third main switch transistor receives a third main control signal, and the control terminal of the fourth main switch transistor receives a fourth main control signal. The first end of the first main switch transistor is connected to the positive bus, the second end is connected to the second end of the second main switch transistor, and the first end of the second main switch transistor is connected to the negative bus. The first end of the third main switch transistor is connected to the positive bus, the second end is connected to the second end of the fourth main switch transistor, and the first end of the fourth main switch transistor is connected to the negative bus.

[0021] The first main switch, the second main switch, the third main switch, and the fourth main switch operate in a first operating mode (i.e., low-power mode) and a second operating mode (i.e., CCM mode or multi-channel interleaving mode) based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal, respectively; the first main control signal satisfies: T+= (upos + 2uneg) / (upos) The second main control signal satisfies: T- = (upos + 2uneg) / (upos) (uneg); where T+ represents the first main control signal, T- represents the second main control signal; upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage; the third main control signal has the same waveform as the first main control signal and the wave transmission time is staggered by the first phase; the fourth main control signal has the same waveform as the second main control signal and the wave transmission time is staggered by the first phase.

[0022] In a preferred embodiment of the present invention, the first main switch, the second main switch, the third main switch and the fourth main switch are the same switch, and the first main power inductor L1 and the second main power inductor L2 are the same inductor.

[0023] The first operating mode is a low-power mode, including DCM+QR mode, and the second operating mode includes CCM mode and / or multi-channel interleaved mode. In DCM+QR mode, the first, second, third, and fourth main switches are turned on for a first time based on the first, second, third, and fourth main control signals, respectively, and the inductance currents of the first main power inductor L1 and the second main power inductor L2 rise; the first, second, third, and fourth main switches are then turned off for a second time based on the first, second, third, and fourth main control signals, respectively, and the inductance currents of the first main power inductor L1 and the second main power inductor L2 rise. The inductor currents of the first main power inductor L1 and the second main power inductor L2 decrease; when the inductor currents drop to zero, the parallel capacitors of the first and second main power switches resonate with the first main power inductor L1 for a first resonant time, and the parallel capacitors of the third and fourth main power switches resonate with the second main power inductor L2 for a first resonant time, after which the turn-on signal of the next cycle arrives; wherein the first resonant time is n*Ts+1 / 2Ts, where n is a positive integer, Ts is the resonant period, which is determined by the inductance value of the first main power inductor L1 and the parallel capacitor values ​​of the first and second main power switches.

[0024] In CMM mode, the first, second, third, and fourth main switches are turned on for a first time based on the first, second, third, and fourth main control signals, respectively, and the inductor currents of the first main power inductor L1 and the second main power inductor L2 rise. Subsequently, the first, second, third, and fourth main switches are turned off for a second time based on the first, second, third, and fourth main control signals, respectively, and the inductor currents of the first main power inductor L1 and the second main power inductor L2 decrease. Before the inductor currents have dropped to 0, the turn-on signal for the next cycle arrives. In the multi-channel interleaving mode, the first main switch, the second main switch, and the first main power inductor L1 form the first channel, and the third main switch, the fourth main switch, and the second main power inductor L2 form the first channel. These two channels resonate, therefore the waveform of the third main control signal is the same as that of the first main control signal, but their transmission time phases are interleaved by 180°; the waveform of the fourth main control signal is the same as that of the second main control signal, but their transmission time phases are interleaved by 180°. In other preferred embodiments of the invention, multi-channel interleaving can also be configured, i.e., the main switch module may include a fifth and a sixth switch, with a corresponding third main power inductor, thereby forming a three-channel resonance. In this case, the fifth and sixth main control signals controlling the fifth and sixth switches have the same waveform as the third and fourth main control signals, but their transmission time phases are interleaved by 360 / 3 = 120°, and so on. When K-channel interleaving is configured, the transmission time phases of the main control signals are interleaved by 360 / K°.

[0025] In the real-time hybrid active third harmonic injection rectifier circuit of this invention, since the first main switch, the second main switch, the third main switch, and the fourth main switch operate in a first operating mode and a second operating mode respectively based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal; the first main control signal satisfies: T+= (upos + 2uneg) / (upos) The second main control signal satisfies: T- = (upos + 2uneg) / (upos) (uneg); where T+ represents the first main control signal, T- represents the second main control signal; upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage; the third main control signal has the same waveform as the first main control signal and the emission time is staggered by the first phase; the fourth main control signal has the same waveform as the second main control signal and the emission time is staggered by the first phase; therefore, in different operating modes, the first main switch, the second main switch, the third main switch, and the fourth main switch can all be turned on when the resonant current is 0, thereby reducing switching losses, reducing electromagnetic interference problems, and improving circuit reliability.

[0026] Figure 3 This is a circuit schematic diagram of a preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention; Figure 4 yes Figure 3 The simulation diagram of the DCM+QR operating mode of the hybrid active third harmonic injection rectifier circuit is shown. Figure 5 yes Figure 3 The simulation diagram of the CMM operating mode of the hybrid active third harmonic injection rectifier circuit shown is shown. Figure 6 yes Figure 3 The waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit are shown. Figure 7 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit in CMM operating mode. Figure 8 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit in DCM+QR operating mode. The following will combine... Figures 3-8 A preferred embodiment of the hybrid active third harmonic injection rectifier circuit of the present invention is described below.

[0027] The hybrid active third harmonic injection rectifier circuit of the present invention includes a three-phase uncontrolled rectifier bridge 10, a three-way bidirectional switch module 20, a main switch module 30, a first main power inductor L1 and a second main power inductor L2, a first freewheeling module 40 and a second freewheeling module 50. Further as... Figure 3 As shown, the novel hybrid active third harmonic injection rectifier circuit of the present invention further includes an input filter and a filter capacitor Cbus. The input filter is connected between the three-phase power supply and the input terminal of the three-phase uncontrolled rectifier bridge 10. The filter capacitor Cbus is connected between the positive bus BUS+ and the negative bus BUS-.

[0028] The three-phase uncontrolled rectifier bridge 10 includes a first rectifier diode D1, a second rectifier diode D2, a third rectifier diode D3, a fourth rectifier diode D4, a fifth rectifier diode D5, and a sixth rectifier diode D6. The anode of the first rectifier diode D1 is connected to the cathode of the second rectifier diode D2 and serves as the first input terminal of the three-phase uncontrolled rectifier bridge 10. The anode of the third rectifier diode D3 is connected to the cathode of the fourth rectifier diode D4 and serves as the second input terminal of the three-phase uncontrolled rectifier bridge 10. The anode of the fifth rectifier diode D5 is connected to the cathode of the sixth rectifier diode D6 and serves as the third input terminal of the three-phase uncontrolled rectifier bridge 10. The cathode of the first rectifier diode D1 is connected to the cathodes of the third rectifier diode D3 and the fifth rectifier diode D5 and serves as the first output terminal of the three-phase uncontrolled rectifier bridge 10. The anode of the second rectifier diode D2 is connected to the anodes of the fourth rectifier diode D4 and the sixth rectifier diode D6 and serves as the second output terminal of the three-phase uncontrolled rectifier bridge 10. The first input terminal, the second input terminal, and the third input terminal of the input filter are respectively connected to the first phase power supply, the second phase power supply, and the third phase power supply; the first output terminal, the second output terminal, and the third output terminal of the input filter are respectively connected to the first input terminal, the second input terminal, and the third input terminal of the three-phase uncontrolled rectifier bridge 10.

[0029] The three-way bidirectional switch module 20 includes a first switch Sy1a, a second switch Sy2a, a third switch Sy1b, a fourth switch Sy2b, a fifth switch Sy3a, and a sixth switch Sy3b. The control terminals of the first switch Sy1a and the second switch Sy2a receive a first control signal; the control terminals of the second switch Sy2a and the fourth switch Sy2b receive a second control signal; and the control terminals of the fifth switch Sy3a and the sixth switch Sy3b receive a third control signal. The first terminal of the first switch Sy1a is connected to the first input terminal of the three-way bidirectional switch module 20 and the first input terminal of the three-phase uncontrolled rectifier bridge 10. The first terminal of the third switch Sy1b is connected to... The second input terminal of the three-way bidirectional switch module 20 and the second input terminal of the three-phase uncontrolled rectifier bridge 10 are connected. The first terminal of the fifth switch transistor Sy3a is connected to the third input terminal of the three-way bidirectional switch module 20 and the third input terminal of the three-phase uncontrolled rectifier bridge 10. The second terminal of the first switch transistor Sy1a is connected to the second terminal of the second switch transistor Sy2a. The second terminal of the third switch transistor Sy1b is connected to the second terminal of the fourth switch transistor Sy2b. The second terminal of the fifth switch transistor Sy3a is connected to the second terminal of the sixth switch transistor Sy3b. The first terminals of the second switch transistor Sy2a, the fourth switch transistor Sy2b, and the sixth switch transistor Sy3b are connected to the output terminal of the three-way bidirectional switch module 20. The output terminal of the three-way bidirectional switch module 20 is connected to the first terminal of the first main power inductor L1. The second terminal of the first main power inductor L1 is connected to the first terminal of the main switch module 30. The output terminal of the three-way bidirectional switch module 20 is simultaneously connected to the first terminal of the second main power inductor L2, and the second terminal of the second main power inductor L2 is connected to the fourth terminal of the main switch module 30.

[0030] The main switch module 30 includes a first main switch transistor T+, a second main switch transistor T-, a third main switch transistor T1+, and a fourth main switch transistor T1-. The control terminal of the first main switch transistor T+ receives a first main control signal, the control terminal of the second main switch transistor T- receives a second main control signal, the third main switch transistor T1+ receives a third main control signal, and the fourth main switch transistor T1- receives a fourth main control signal. The first ends of the first main switch transistor T+ and the first ends of the third main switch transistor T1+ constitute the second end of the main switch module 30 and are connected to the positive bus BUS+. The second end of the first main switch transistor T+ is connected to the second end of the second main switch transistor T- and constitutes the first end of the main switch module 30. The second end of the third main switch transistor T+ is connected to the second end of the fourth main switch transistor T- and constitutes the fourth end of the main switch module 30. The first ends of the second main switch transistor T- and the first ends of the fourth main switch transistor T1- constitute the third end of the main switch module 30 and are connected to the negative bus BUS-.

[0031] exist Figure 3 In the preferred embodiment shown, the first freewheeling module 40 includes a first freewheeling capacitor C1 and a first freewheeling diode D7, and the second freewheeling module 50 includes a second freewheeling capacitor C2 and a second freewheeling diode D8. The positive terminal of the first freewheeling capacitor C1 is connected to the positive busbar BUS+, and the negative terminal is connected to the first terminal of the first main power inductor L1. The cathode of the first freewheeling diode D7 is connected to the positive busbar BUS+, and the anode is connected to the first terminal of both the first main power inductor L1 and the second main power inductor L2. The negative terminal of the second freewheeling capacitor C2 is connected to the negative busbar BUS-, and the positive terminal is connected to the first terminal of the first main power inductor L1. The anode of the second freewheeling diode D8 is connected to the negative busbar BUS-, and the cathode is connected to the first terminal of both the first main power inductor L1 and the second main power inductor L2. The second end of the first main power inductor L1 is connected to the first end of the main switch module (i.e., the second end of the first main switch T+ and the second end of the second main switch T-), and the second end of the second main power inductor L2 is connected to the fourth end of the main switch module (the second end of the third main switch T+ and the second end of the fourth main switch T-).

[0032] like Figure 3As shown, the first to sixth rectifier diodes D1, D2, D3, D4, D5, and D6 are the input three-phase uncontrolled rectifier diodes. The first switch Sy1a, second switch Sy2a, third switch Sy1b, fourth switch Sy2b, fifth switch Sy3a, and sixth switch Sy3b are MOSFETs or IGBTs, primarily controlling the commutation of the three-phase current in the middle section. The first main switch T+ and second main switch T- are also MOSFETs or IGBTs, primarily controlling the three-phase current in the middle section to follow the changes in the middle phase voltage. The filter capacitor Cbus is used to filter out high-frequency signals generated by the circuits downstream of the positive and negative buses; the input filter is a low-pass filter circuit or module, primarily filtering out high-frequency signals in the main power circuit. When the first switch Sy1a, the second switch Sy2a, the third switch Sy1b, the fourth switch Sy2b, the fifth switch Sy3a, and the sixth switch Sy3b are all inactive, the first freewheeling capacitor C1, the first freewheeling diode D7, the second freewheeling capacitor C2, and the second freewheeling diode D8 provide a freewheeling circuit for the first main power inductor L1. Simultaneously, the first freewheeling capacitor C1 and the second freewheeling capacitor C2 can also be used to filter high-frequency signals in the circuit. In a preferred embodiment of the present invention, only the first freewheeling capacitor C1 and the second freewheeling capacitor C2, or only the first freewheeling diode D7 and the second freewheeling diode D8, may be used.

[0033] The following is combined with Figures 3-8 The principle of the hybrid active third harmonic injection rectifier circuit of the present invention is explained below. The hybrid active third harmonic injection rectifier circuit of the present invention employs dual-mode control. The first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- operate in a first operating mode and a second operating mode, respectively, based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal. The first operating mode includes DCM+QR mode, and the second operating mode includes CCM mode and / or multi-channel interleaved mode.

[0034] We will explain using DCM+QR mode and CCM mode as follows. The first main control signal satisfies: T+= (upos + 2uneg) / (upos) The second main control signal satisfies: T- = (upos + 2uneg) / (upos) The waveform of the third main control signal is the same as that of the first main control signal, and the waveform of the second main control signal is the same as that of the second main control signal. Upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage; that is, upos = max(ua, ub, uc); uneg = min(ua, ub, uc), where ua, ub, and uc represent the first phase voltage, the second phase voltage, and the third phase voltage, respectively. The waveform of the third main control signal is the same as that of the first main control signal, and the transmission time is staggered by the first phase. The waveform of the fourth main control signal is the same as that of the second main control signal, and the transmission time is staggered by the first phase.

[0035] The working principle of DCM+QR (Valley-to-Conduction) mode is as follows: According to the above-mentioned wave generation logic (i.e., using the aforementioned first main control signal, second main control signal, third main control signal, and fourth main control signal), the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned on first. At this time, the inductor currents of the first main power inductor L1 and the second main power inductor L2 rise. When the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned off, the inductor currents of the first main power inductor L1 and the second main power inductor L2 begin to decrease. When the inductor current drops to a certain value... At 0A, the parallel capacitances (including the DS junction capacitances of the switches) of the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- resonate with the first main power inductor L1 and the second main power inductor L2, respectively, for the first resonance time (e.g., n*Ts+1 / 2*Ts, where n is a positive integer and Ts is the resonance period). The junction voltages of the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are at the resonance valley. At this time, the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned on again, completing one working cycle. The simulated waveform is as follows. Figure 4As shown, n is a natural number such as 0, 1, 2, 3, etc., and Ts is the resonant period, which is determined by the inductance value of the first main power inductor L1 (or the second main power inductor L2) and the parallel capacitance values ​​of the first main switch, the second main switch (or the third main switch and the fourth main switch). To improve efficiency, we usually control the QR time to 1 / 2*Ts. However, when upos + 2uneg or 2upos + uneg is very small, the frequency of DCM+QR will be very large. Due to the limitations of the DSP and the technology of components such as the switching transistors, the switching frequency cannot be too large, so the frequency can be reduced by increasing the number of resonants. When the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned on, the voltage difference Vds between the drain and source of the main switch is at the bottom of the resonant waveform, and the current flowing through the main switch is almost 0 at this time, so the turn-on loss is very small, thereby reducing the loss of the switching transistor.

[0036] In this invention, the control logic employs a method where the average current of the first main power inductor L1 and / or the second main power inductor L2 follows the variation of the middle phase voltage in the three-phase input voltage. Therefore, with a constant power and input voltage, the average current remains constant. Since the peak current in DCM+QR mode control is greater than twice the average current, and the peak current increases with increasing load or decreasing input voltage, briefly allowing the inductor current to enter CCM mode becomes an option to reduce current stress. Alternatively, multiple interleaved parallel connections or both can be used.

[0037] CCM mode working principle: According to the above waveform generation logic (i.e., using the aforementioned first main control signal, second main control signal, third main control signal, and fourth main control signal), the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned on first. At this time, the inductor currents of the first main power inductor L1 and the second main power inductor L2 rise. When the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- are turned off, the inductor currents of the first main power inductor L1 and the second main power inductor L2 begin to decrease. Before the inductor current drops to 0A, the turn-on signal of the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- arrives in the next cycle, thus entering the next cycle; the simulation waveform is as follows. Figure 5 As shown.

[0038] The working principle of multi-channel interleaved parallel connection, combined with Figure 3The diagram shows two interleaved parallel circuits. The first main switch T+, the second main switch T-, and the first main power inductor L1 form the first circuit, while the third main switch T1+, the fourth main switch T1-, and the second main power inductor L2 form the second circuit. Since the circuit parameters and waveform generation logic are the same for both circuits, their switching periods are equal at any given time, denoted as Tf. The waveform generation times of the first and second circuits need to be staggered by 1 / 2 * Tf, also known as a 180° phase shift. Similarly, for K interleaved parallel circuits, the waveform generation times of adjacent circuits need to be staggered by 1 / K * Tf, i.e., a 360° / K phase shift.

[0039] In this invention, the duty cycle and frequency of the DCM+QR mode are both variable; the CCM mode has a fixed frequency and adjustable duty cycle. The CCM mode and multi-channel interleaved parallel connection can be selected individually, or both. In multi-channel interleaved parallel connection, the mode control current is the average current after the superposition of the multiple inductor currents.

[0040] Figure 6 yes Figure 3 The waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit are shown. Figure 7 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage of the hybrid active third harmonic injection rectifier circuit in CMM operating mode. Figure 8 yes Figure 3 The diagram shows the expanded waveforms of the output bus voltage, main power inductor current, and three-phase input voltage in the DCM+QR operating mode of the hybrid active third harmonic injection rectifier circuit. Figures 6-8 As shown, a three-phase AC power supply with Vin=380Vac is used to output a constant power module of 60KW. Figure 7 The waveforms are expanded to show the first main power inductor L1 and the second main power inductor L2 operating in CCM mode. Figure 8 The waveforms are expanded when the first main power inductor L1 and the second main power inductor L2 are operating in DCM+QR mode.

[0041] Combination Figures 6-8 It can be seen that, under different operating modes, the first main switch T+, the second main switch T-, the third main switch T1+, and the fourth main switch T1- can all be turned on when the resonant current is 0, thereby reducing switching losses, reducing electromagnetic interference problems, and improving circuit reliability.

[0042] Although the present invention has been described through specific embodiments, those skilled in the art will understand that various modifications and equivalent substitutions can be made to the invention without departing from its scope. Furthermore, various modifications can be made to the invention for specific situations or materials without departing from its scope. Therefore, the present invention is not limited to the specific embodiments disclosed, but should include all embodiments falling within the scope of the claims.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for a hybrid active third harmonic injection rectifier circuit, characterized in that, The hybrid active third harmonic injection rectifier circuit includes a three-phase uncontrolled rectifier bridge, a three-way bidirectional switch module, a main switch module, and a first main power inductor. The first input terminal of the three-phase uncontrolled rectifier bridge is connected to the first phase power supply and the first input terminal of the three-way bidirectional switch module; the second input terminal of the three-phase uncontrolled rectifier bridge is connected to the second phase power supply and the second input terminal of the three-way bidirectional switch module; the third input terminal of the three-phase uncontrolled rectifier bridge is connected to the third phase power supply and the third input terminal of the three-way bidirectional switch module; the first output terminal of the three-phase uncontrolled rectifier bridge is connected to the positive bus, and the second output terminal is connected to the negative bus. The output terminal of the three-way bidirectional switch module is connected to the first terminal of the first main power inductor and the first terminal of the second main power inductor. The second terminal of the first main power inductor is connected to the first terminal of the main switch module. The second terminal of the main switch module is connected to the positive bus and the third terminal is connected to the negative bus. The main switch module includes a first main switch transistor and a second main switch transistor; the control terminal of the first main switch transistor receives a first main control signal, and the control terminal of the second main switch transistor receives a second main control signal. The first end of the first main switch is connected to the positive bus, the second end is connected to the second end of the second main switch, and the first end of the second main switch is connected to the negative bus. The first main switch and the second main switch operate in low-loss mode and CCM mode respectively based on the first main control signal and the second main control signal.

2. The control method for the hybrid active third harmonic injection rectifier circuit according to claim 1, characterized in that, The main switch module further includes a third main switch transistor and a fourth main switch transistor; the hybrid active third harmonic injection rectifier circuit further includes a second main power inductor. The control terminal of the third main switch receives the third main control signal, the control terminal of the fourth main switch receives the fourth main control signal, the first terminal of the third main switch is connected to the positive bus, the second terminal is connected to the second terminal of the fourth main switch, and the first terminal of the fourth main switch is connected to the negative bus. The first end of the second main power inductor is connected to the output end of the three-way bidirectional switch module, and the second end is connected to the second end of the third main switch and the second end of the fourth main switch. The first main switch, the second main switch, the third main switch, and the fourth main switch operate in low-loss mode and CCM mode respectively based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal; or The first main switch, the second main switch, the third main switch, and the fourth main switch operate in low-loss mode and multi-channel interleaving mode respectively based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal.

3. The control method for the hybrid active third harmonic injection rectifier circuit according to claim 2, characterized in that, The first main control signal satisfies: T+= (upos + 2uneg) / (upos) uneg); The second main control signal satisfies: T- = (upos + 2uneg) / (upos) uneg); Wherein, T+ represents the first main control signal, T- represents the second main control signal; upos represents the maximum value of the three-phase voltage, and uneg represents the minimum value of the three-phase voltage; The third main control signal has the same waveform as the first main control signal and the transmission time is staggered by the first phase; the fourth main control signal has the same waveform as the second main control signal and the transmission time is staggered by the first phase.

4. The control method for the hybrid active third harmonic injection rectifier circuit according to claim 3, characterized in that, The low-loss operating mode includes the DCM+QR mode; in the DCM+QR mode, when the first main switch, the second main switch, the third main switch and the fourth main switch are turned on for a first time based on the first main control signal, the second main control signal, the third main control signal and the fourth main control signal respectively, the inductance current of the first main power inductor and the second main power inductor rises. The first main switch, the second main switch, the third main switch, and the fourth main switch are then disconnected for a second time based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal, respectively, and the inductance current of the first main power inductor and the second main power inductor decreases. When the inductor current drops to zero, the parallel capacitor of the first main switch and the second main switch resonates with the first main power inductor for a first resonant time, and the parallel capacitor of the third main switch and the fourth main switch resonates with the second main power inductor for a first resonant time, and then the turn-on signal of the next cycle arrives. The first resonance time is n*Ts+1 / 2Ts, where n is a positive integer and Ts is the resonance period.

5. The control method for the hybrid active third harmonic injection rectifier circuit according to claim 3, characterized in that, In CMM mode, when the first main switch, the second main switch, the third main switch and the fourth main switch are turned on for a first time based on the first main control signal, the second main control signal, the third main control signal and the fourth main control signal respectively, the inductance current of the first main power inductor and the second main power inductor rises. The first main switch, the second main switch, the third main switch, and the fourth main switch are then disconnected for a second time based on the first main control signal, the second main control signal, the third main control signal, and the fourth main control signal, respectively. The inductor current of the first main power inductor and the second main power inductor decreases. Before the inductor current decreases to 0, the turn-on signal of the next cycle arrives.

6. The control method for the hybrid active third harmonic injection rectifier circuit according to claim 3, characterized in that, In the multi-channel interleaved mode, the third main control signal has the same waveform as the first main control signal but the transmission time phase is interleaved by 180°; the fourth main control signal has the same waveform as the second main control signal but the transmission time phase is interleaved by 180°.

7. The control method for the hybrid active third harmonic injection rectifier circuit according to any one of claims 1 to 6, characterized in that, The hybrid active third harmonic injection rectifier circuit further includes a first freewheeling module and a second freewheeling module. The first freewheeling module includes a first freewheeling capacitor and a first freewheeling diode, and the second freewheeling module includes a second freewheeling capacitor and a second freewheeling diode; The positive terminal of the first freewheeling capacitor is connected to the positive busbar, and the negative terminal is connected to the first end of the first main power inductor. The cathode of the first freewheeling diode is connected to the positive busbar, and the anode is connected to the first end of the first main power inductor. The negative terminal of the second freewheeling capacitor is connected to the negative busbar, and the positive terminal is connected to the first terminal of the second main power inductor. The anode of the second freewheeling diode is connected to the negative busbar, and the cathode is connected to the first terminal of the second main power inductor.

8. The control method for the hybrid active third harmonic injection rectifier circuit according to any one of claims 1 to 6, characterized in that, The three-phase uncontrolled rectifier bridge includes a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a fifth rectifier diode, and a sixth rectifier diode; The anode of the first rectifier diode is connected to the cathode of the second rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fifth rectifier diode is connected to the cathode of the sixth rectifier diode, the cathode of the first rectifier diode is connected to the cathodes of the third and fifth rectifier diodes, and the anode of the second rectifier diode is connected to the anodes of the fourth and sixth rectifier diodes.

9. The control method for the hybrid active third harmonic injection rectifier circuit according to any one of claims 1 to 6, characterized in that, The three-way bidirectional switch module includes a first switch transistor, a second switch transistor, a third switch transistor, a fourth switch transistor, a fifth switch transistor, and a sixth switch transistor; The control terminals of the first and second switching transistors receive a first control signal; The control terminals of the second and fourth switching transistors receive the second control signal; The control terminals of the fifth and sixth switching transistors receive a third control signal; The first end of the first switching transistor is connected to the first input terminal of the three-way bidirectional switch module, the first end of the third switching transistor is connected to the second input terminal of the three-way bidirectional switch module, and the first end of the fifth switching transistor is connected to the third input terminal of the three-way bidirectional switch module. The second end of the first switch is connected to the second end of the second switch, the second end of the third switch is connected to the second end of the fourth switch, the second end of the fifth switch is connected to the second end of the sixth switch, and the first ends of the second switch, the fourth switch, and the sixth switch are connected to the output end of the three-way bidirectional switch module.

10. The control method for the hybrid active third harmonic injection rectifier circuit according to any one of claims 1 to 6, characterized in that, The hybrid active third harmonic injection rectifier circuit further includes an input filter; The first input terminal, the second input terminal, and the third input terminal of the input filter are respectively connected to the first phase power supply, the second phase power supply, and the third phase power supply; the first output terminal, the second output terminal, and the third output terminal of the input filter are respectively connected to the first input terminal, the second input terminal, and the third input terminal of the three-phase uncontrolled rectifier bridge.

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