A dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter

Abstract

The application discloses a double-winding magnetic core resonant high-frequency soft-switching DC / AC converter, which comprises a no-bridge-arm through double-channel architecture main power circuit, a current positive double-winding magnetic integrated passive resonance circuit, a current negative double-winding magnetic integrated passive resonance circuit, a dynamic potential equalization circuit and a harmonic suppression shaping circuit. The application does not need any additional switching tube to realize soft switching, which greatly simplifies the design of the control circuit, and only uses a small amount of elements to create the soft switching condition of the high-frequency switching tube, which is of great help to improve the power density of the system. Due to the existence of the turn ratio of the energy injection side winding and the energy receiving side winding of the double-winding magnetic core mutual inductance element, the voltage stress and the current stress of the switching tube can be easily reduced, the switching loss is reduced, the efficiency is improved, which is beneficial to improve the working frequency of the system, and then the element volume of the harmonic suppression shaping part of the converter is reduced, and the power density of the converter is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of inverter in electric energy conversion device, and particularly relates to a double-winding magnetic core resonant high-frequency soft switching DC / AC converter. BACKGROUND

[0002] In recent years, the switching tube working frequency of the DC / AC converter is higher and higher. The advantage of the working frequency increase is that the volume of the harmonic suppression element of the converter can be greatly reduced, which is beneficial to improve the overall power density of the converter, and can also make the response speed of the converter to the load change faster, and improve the dynamic performance of the system. However, the increase of the switching tube working frequency has an inherent problem, that is, the switching process is hard switching, which leads to large switching loss and electromagnetic interference, which will limit the working efficiency of the converter, so that the working frequency of the switching tube in the converter should not be too high, and therefore the soft switching technology is a research hotspot in recent years. SUMMARY

[0003] Technical purpose: in view of the defects of the full-bridge converter in the prior art, the present application discloses a double-winding magnetic core resonant high-frequency soft switching DC / AC converter, proposes a no-bridge-arm-through double-channel main power transmission architecture, and connects two high-frequency modulated power switching tubes in the no-bridge-arm-through double-channel main power transmission architecture with a set of passive resonance circuits based on double-winding magnetic core mutual inductance elements, simultaneously introduces a dynamic potential equalization circuit and a harmonic suppression shaping circuit, and proposes a double-winding magnetic core resonant high-frequency soft switching DC / AC converter which enables the two high-frequency modulated power switching tubes in the no-bridge-arm-through double-channel main power transmission architecture to realize soft switching without additional switching and greatly simplifies the control circuit.

[0004] Technical scheme: in order to achieve the above technical purpose, the present application adopts the following technical scheme.

[0005] A double-winding magnetic core resonant high-frequency soft switching DC / AC converter, comprising a no-bridge-arm-through double-channel architecture main power circuit, a current forward double-winding magnetic integrated passive resonance circuit, a current negative double-winding magnetic integrated passive resonance circuit, a dynamic potential equalization circuit and a harmonic suppression shaping circuit.

[0006] The no-bridge-arm-through double-channel architecture main power circuit is used for transmitting positive and negative harmonic suppression inductor currents i L The no-bridge-arm-through double-channel architecture main power circuit is used for transmitting positive and negative harmonic suppression inductor currents i L1, the first freewheeling diode D1; the negative harmonic suppression inductance current transmission path comprises a second high-frequency modulation switch S2, a second current commutation power-frequency modulation switch Q L2 and the second freewheeling diode D2;

[0007] The current forward double-winding magnetic integrated passive resonance circuit is connected with the main power circuit of the no-bridge-arm shoot-through dual-channel architecture, and is used for creating a soft switching condition for the first high-frequency modulation switch S1 when the first high-frequency modulation switch S1 performs high-frequency switching operation, so as to reduce switching loss and current and voltage stress of the high-frequency switch.

[0008] The current negative double-winding magnetic integrated passive resonance circuit is connected with the main power circuit of the no-bridge-arm shoot-through dual-channel architecture, and is used for creating a soft switching condition for the second high-frequency modulation switch S2 when the second high-frequency modulation switch S2 performs high-frequency switching operation, so as to reduce switching loss and current and voltage stress of the high-frequency switch.

[0009] The dynamic potential equalization circuit is connected with the harmonic suppression and shaping circuit, and is used for dynamic adjustment of the potential at the end of the harmonic suppression capacitor, so that the harmonic suppression and shaping circuit can correctly output a voltage suitable for the direction.

[0010] The harmonic suppression and shaping circuit is connected with the main power circuit of the no-bridge-arm shoot-through dual-channel architecture, and is used for adjusting the output voltage waveform and suppressing the generation of high-frequency harmonics.

[0011] Advantages:

[0012] (1) The high-frequency modulation power switch in the proposed topology can realize soft switching, reduce switching loss, improve the overall efficiency of the converter, and limit the influence of electromagnetic interference;

[0013] (2) The power switch in the proposed topology can work at a high switching frequency, which helps to reduce the size of the harmonic suppression element, and only a small number of elements are needed to realize soft switching, which greatly helps to improve the power density of the system;

[0014] (3) The realization of soft switching does not need additional switches to assist, which greatly simplifies the logic of the control circuit.

[0015] (4) The main power freewheeling diode of the topology is turned off under the ZV and ZCS conditions, and the freewheeling diode of the resonance module is turned off under the ZCS condition, which avoids the generation of reverse recovery current of the diode, so there is no reverse recovery problem.

[0016] (5) Due to the existence of the turn ratio of the energy injection side winding and the energy receiving side winding of the double-winding magnetic core type mutual inductor element, the topology can reduce the voltage and current stress of the switch by selecting a suitable transformation ratio, which is beneficial to the cost control of the converter. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A double-winding magnetic core resonant high-frequency soft switching DC / AC converter topology structure diagram of the present application;

[0018] Figure 2 A control driving waveform diagram of each switch tube when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter of the present application works in four quadrants;

[0019] Figure 3 A key waveform diagram of the converter when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter circuit of the present application works in the first quadrant;

[0020] Figures 4 to 9 A switch mode diagram of each switch when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter circuit of the present application works in the first quadrant;

[0021] Figures 10 to 15 A switch mode diagram of each switch when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter circuit of the present application works in the second quadrant;

[0022] Figures 16 to 21 A switch mode diagram of each switch when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter circuit of the present application works in the third quadrant;

[0023] Figures 22 to 27 A switch mode diagram of each switch when the double-winding magnetic core resonant high-frequency soft switching DC / AC converter circuit of the present application works in the fourth quadrant. DETAILED DESCRIPTION

[0024] In order to enable persons skilled in the art to better understand the scheme of the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative labor fall within the scope of protection of the present application.

[0025] As shown in the accompanying drawings, Figure 1 A double-winding magnetic core resonant high-frequency soft switching DC / AC converter includes a no-bridge-arm through double-channel architecture main power circuit 1, a current forward double-winding magnetic integrated passive resonance circuit 2, a current negative double-winding magnetic integrated passive resonance circuit 3, a dynamic potential equalization circuit 4, and a harmonic suppression shaping circuit 5.

[0026] The no-bridge-arm through double-channel architecture main power circuit 1 is used to control the positive and negative harmonic suppression inductor current i LThe application provides an adaptive main power transmission path and high-frequency chopping of input voltage. The main power circuit 1 of the no-bridge-arm straight-through double-channel architecture comprises a forward harmonic suppression inductive current transmission path and a negative harmonic suppression inductive current transmission path, wherein the forward and negative directions of the forward harmonic suppression inductive current transmission path and the negative harmonic suppression inductive current transmission path refer to the forward and negative directions of the harmonic suppression inductive current i L , and the current negative double-winding magnetic integrated passive resonance circuit 3 is the same; the forward harmonic suppression inductive current transmission path comprises a first high-frequency modulation switch tube S1, a first current reversing industrial-frequency modulation switch tube Q L1 , and a first freewheeling diode D1; the negative harmonic suppression inductive current transmission path comprises a second high-frequency modulation switch tube S2, a second current reversing industrial-frequency modulation switch tube Q L2 , and a second freewheeling diode D2.

[0027] As shown in the accompanying Figure 1 , the circuit connection structure is as follows:

[0028] The main power circuit 1 of the no-bridge-arm straight-through double-channel architecture comprises a first high-frequency modulation switch tube S1 and a second high-frequency modulation switch tube S2, a first current reversing industrial-frequency modulation switch tube Q L1 and a second current reversing industrial-frequency modulation switch tube Q 12 , and a first freewheeling diode D1 and a second freewheeling diode D2; wherein the source electrode of the first high-frequency modulation switch tube S1 is connected to the drain electrode of the first current reversing industrial-frequency modulation switch tube Q L1 and the cathode of the first freewheeling diode D1, the anode of the first freewheeling diode D1 is connected to the negative electrode of an input power supply V in , and together constitutes the forward harmonic suppression inductive current transmission path and high-frequency chopping of input voltage. The drain electrode of the second high-frequency modulation switch tube S2 is connected to the source electrode of the second current reversing industrial-frequency modulation switch tube Q L2 and the anode of the second freewheeling diode D2, the cathode of the second freewheeling diode D2 is connected to the positive electrode of the input power supply V in , and together constitutes the negative harmonic suppression inductive current transmission path and high-frequency chopping of input voltage, and the drain electrode of the second current reversing industrial-frequency modulation switch tube Q L2 is connected to the source electrode of the first current reversing industrial-frequency modulation switch tube Q L1 , and the forward harmonic suppression inductive current transmission path and the negative harmonic suppression inductive current transmission path constitute the overall main power transmission path.

[0029] Among them, the current-forward dual-winding magnetically integrated passive resonant circuit 2 is connected to the bridge-arm-less through-dual-channel main power circuit 1, which is used to create soft-switching conditions for the first high-frequency modulation switch S1 when it performs high-frequency switching operation, thereby reducing the switching loss and current and voltage stress of the high-frequency switch.

[0030] The current-forward dual-winding magnetically integrated passive resonant circuit 2 includes a first energy-injected magnetic pole winding inductor L. r1 First energy receiving magnetic pole winding inductance L r2 The first resonant cavity energy interaction capacitor C r1 and the third freewheeling diode D a Among them, the first energy injection magnetic pole winding inductance L r1 First energy receiving magnetic pole winding inductance L r2 This constitutes a set of dual-winding magnetic core mutual inductance elements, with the first energy injected into the magnetic pole winding inductance L. r1 As the primary side, the inductance L of the first energy receiving magnetic pole winding r2 As the secondary side; the energy interaction capacitor C between the dual-winding magnetic core and the first resonant cavity r1 At resonance, the inductor and capacitor exchange energy reactively. The first energy is injected into the magnetic pole winding inductor L. r1 The magnetic pole synchronization terminal and the first energy receiving magnetic pole winding inductor L r2 The non-magnetic pole synchronization terminal is connected to the input power supply V. in The positive terminal, the first energy is injected into the magnetic pole winding inductor L r1 The non-magnetic pole synchronization terminal is connected to the drain of the first high-frequency modulation switch S1, and the first energy receiving magnetic pole winding inductance L r2 The magnetic pole synchronization terminal is connected to the third freewheeling diode D. a The cathode, the third freewheeling diode D a The anode is connected to the cathode of the first freewheeling diode D1, the source of the first high-frequency modulation switch S1, and the first current-commutating power frequency modulation switch Q. L1 The drain electrode, and the energy interaction capacitor C of the first resonant cavity. r1 One end is connected to the first resonant cavity energy interaction capacitor C. r1 The other end is connected to the input power supply V. in The negative terminal. Therefore, the first energy is injected into the magnetic pole winding inductance L. r1 First energy receiving magnetic pole winding inductance L r2 The first resonant cavity energy interaction capacitor C r1 and the third freewheeling diode D a Together they form a current-forward dual-winding magnetically integrated passive resonant circuit, providing ZCS turn-on and ZVS turn-off conditions for the first high-frequency modulation switch S1.

[0031] The current negative double-winding magnetic integrated passive resonance circuit 3 is connected with the bridgeless dual-channel main power circuit 1, and is used for creating soft switching conditions for the second high-frequency modulation switch tube S2 during high-frequency switching operation, so as to reduce switching loss and current and voltage stress of the high-frequency switch tube.

[0032] The current negative double-winding magnetic integrated passive resonance circuit 3 comprises a second energy injection magnetic pole winding inductor L r3 , a second energy receiving magnetic pole winding inductor L r4 , a second resonance cavity energy interaction capacitor C r2 and a fourth freewheeling diode D b . The second energy injection magnetic pole winding inductor L r3 and the second energy receiving magnetic pole winding inductor L r4 constitute a set of double-winding magnetic core mutual inductance elements, the second energy injection magnetic pole winding inductor L r3 serves as a primary side, and the second energy receiving magnetic pole winding inductor L r4 serves as a secondary side; the double-winding magnetic core and the second resonance cavity energy interaction capacitor C r2 resonate to exchange energy between the inductor and the capacitor. The non-magnetic pole synchronous terminal of the second energy injection magnetic pole winding inductor L r3 is connected to the anode of the fourth freewheeling diode D b , the negative electrode of the input power supply V in , the magnetic pole synchronous terminal of the second energy injection magnetic pole winding inductor L r3 is connected to the source electrode of the second high-frequency modulation switch tube S2, the magnetic pole synchronous terminal of the second energy receiving magnetic pole winding inductor L r4 is connected to the cathode of the fourth freewheeling diode D b , the non-magnetic pole synchronous terminal of the second energy receiving magnetic pole winding inductor L r4 is connected to the anode of the second freewheeling diode D2, the drain electrode of the second high-frequency modulation switch tube S2 and the source electrode of the second current commutation power-frequency modulation switch tube Q L2 , and is connected to one end of the second resonance cavity energy interaction capacitor C r2 , and the other end of the second resonance cavity energy interaction capacitor C r2 is connected to the positive electrode of the input power supply V in . Therefore, the second energy injection magnetic pole winding inductor L r3 , the second energy receiving magnetic pole winding inductor L r4 , the second resonance cavity energy interaction capacitor C r2 and the fourth freewheeling diode D b together constitute the current negative double-winding magnetic integrated passive resonance circuit, and provide ZCS turn-on and ZVS turn-off conditions for the second high-frequency modulation switch tube S2.

[0033] The dynamic potential equalization circuit 4 is connected to the harmonic suppression and shaping circuit 5, and is used for dynamic adjustment of the potential at the end of the harmonic suppression capacitor, so that the harmonic suppression and shaping circuit can correctly output a voltage in the appropriate direction. The dynamic potential equalization circuit 4 includes a first dynamic potential regulating power frequency switch Q1 and a second dynamic potential regulating power frequency switch Q2, wherein the source of the first dynamic potential regulating power frequency switch Q1 is connected to the input power supply V. in The negative terminal of the first dynamic potential regulating power frequency switch Q1 is connected to the source of the second dynamic potential regulating power frequency switch Q2 and grounded. The drain of the second dynamic potential regulating power frequency switch Q2 is connected to the input power supply V. in The positive terminal. Therefore, the first dynamic potential regulating power frequency switch Q1 and the second dynamic potential regulating power frequency switch Q2 together constitute a dynamic potential equalization circuit, which performs commutation operation for the output voltage.

[0034] Harmonic suppression and shaping circuit 5 is connected to the bridgeless, direct-through dual-channel main power circuit 1, and is used to shape the output voltage waveform and suppress the generation of high-frequency harmonics. Harmonic suppression and shaping circuit 5 includes a harmonic suppression inductor L. f Harmonic suppression capacitor C f Among them, the harmonic suppression inductor L f One end is connected to the second current-commutating power frequency modulation switch transistor Q. L2 The drain of the first current-commutated power frequency modulation switch Q L1 The source of the harmonic suppression inductor L f The other end is connected to the output harmonic suppression capacitor C. f At one end, the harmonic suppression capacitor C f The other end is connected to the drain of the first dynamic potential regulating power frequency switch Q1 and the source of the second dynamic potential regulating power frequency switch Q2, and grounded; harmonic suppression inductor L f The current on it is denoted as inductor current i. L Harmonic suppression capacitor C f The voltage across the two terminals is the output voltage V. O Define the inductor current i L Flow to harmonic suppression capacitor C f The direction of the positive extreme is positive, as shown in the attached diagram. Figure 1 As shown. Therefore, the harmonic suppression inductor L f Harmonic suppression capacitor C f Together, they form a harmonic suppression and shaping circuit, which adjusts the output waveform and suppresses the generation of high-frequency harmonics.

[0035] With output voltage V O The x-axis represents the inductor current i. L Using the vertical axis as the ordinate, the converter of this invention can be divided into four quadrants during operation, as follows:Figure 1 The main circuit structure is shown, the control driving waveforms in four quadrants and the output waveforms are shown as Figure 2 The control signal is connected with the gate of each switch tube to provide the turn-on and turn-off of each switch tube, combined with Figures 4-27 The working principle and working mode of the double-winding magnetic core resonant high-frequency soft switching DC / AC converter in the four quadrants under the PWM control, i.e. the single-polarity SPWM modulation mode, are specifically discussed, and the electrical elements specifically involved include two high-frequency main power switch tubes, two current commutation power frequency main power switch tubes, two dynamic potential regulating power frequency switch tubes, four freewheeling diodes, two double-winding magnetic core type mutual inductance elements, two resonant cavity energy interaction capacitors, harmonic suppression inductors, harmonic suppression capacitors and an external power supply. The present application does not need any additional switch tube to realize soft switching, which greatly simplifies the design of the control circuit, and only a small number of elements are used to create the soft switching condition of the high-frequency switch tube, which greatly helps to improve the power density of the system. In addition, due to the existence of the turn ratio of the energy injection side winding and the energy receiving side winding of the double-winding magnetic core type mutual inductance element, the voltage stress and current stress of the switch tube can be easily reduced, thereby reducing the switching loss and improving the efficiency, which is conducive to improving the working frequency of the system, thereby reducing the size of the elements of the harmonic suppression shaping part of the converter and improving the power density of the converter.

[0036] When the double-winding magnetic core resonant high-frequency soft switching DC / AC converter works in the first quadrant (V O >0, i L >0):

[0037] When the circuit works in the first quadrant, the first dynamic potential regulating power frequency switch tube Q1 in the dynamic potential balancing circuit and the first current commutation power frequency modulation switch tube Q L1 are turned on, the first high-frequency modulation switch tube S1 in the no-bridge-arm-through double-channel architecture main power circuit performs high-frequency switching operation, and the remaining switch tubes are turned off. Before working mode 1, it is assumed that the first high-frequency modulation switch tube S1 is turned off and the harmonic suppression inductor current i L flows through the first freewheeling diode D1, and the key waveforms when the quadrant works are shown as Figure 3 Since the key waveforms when other quadrants work are similar, they will not be listed when discussing the working modes of other quadrants. The working modes when this quadrant works are shown as Figures 4-9 .

[0038] Working mode 1: as shown in Figure 4 , the first high-frequency modulation switch tube S1 is turned on, and since the energy injection magnetic pole winding inductance of the double-winding magnetic core, i.e. the first energy injection magnetic pole winding inductance L r1the current flowing through the first high-frequency modulation switch S1 will rise slowly and linearly, and thus the first high-frequency modulation switch S1 is turned on under ZCS condition, at which time the current in the first freewheeling diode D1 will decrease linearly, and when the current of the first high-frequency modulation switch S1 rises to the harmonic suppression inductance current i L , this working mode ends.

[0039] Working mode 2: As shown in Figure 5 , since the current of the first high-frequency modulation switch S1 has risen to the harmonic suppression inductance current i L , the first freewheeling diode D1 is turned off, and is turned off under ZCS condition. The first energy injection pole winding inductance L r1 of the double-winding magnetic core and the first resonant cavity energy interaction capacitor C r1 start to resonate, and since the first resonant cavity energy interaction capacitor C r1 , the rise of the voltage of the first freewheeling diode D1 can be considered to be slow, and thus the turn-off of the first freewheeling diode D1 is ZCZVS. When the voltage of the first resonant cavity energy interaction capacitor C r1 rises to the input voltage V in , this working mode ends.

[0040] Working mode 3: As shown in Figure 6 , when the voltage of the first resonant cavity energy interaction capacitor C r1 rises to the input voltage V in , the third freewheeling diode D a in the current positive double-winding magnetic integrated passive resonant circuit starts to conduct, and conducts under ZVS, the voltage of the first resonant cavity energy interaction capacitor C r1 is clamped at the input voltage V in , and the total ampere turns of the first energy injection pole winding inductance L r1 and the first energy receiving pole winding inductance L r2 of the double-winding magnetic core should remain constant. When the first high-frequency modulation switch S1 is turned off, this working mode ends.

[0041] Working mode 4: As shown in Figure 7 , at this time the first high-frequency modulation switch S1 is turned off under ZVS condition, however in actual cases, since the energy of the double-winding magnetic core mutual inductance element will leak and thus exhibit the characteristics of a leakage inductance, a small voltage spike will appear across the switch, but the spike peak value is usually much smaller than the maximum voltage of the switch, and thus the first high-frequency modulation switch S1 can also be turned off under near-ZVS condition. The ampere turns of the first energy injection pole winding inductance L r1 of the double-winding magnetic core are transferred to the first energy receiving pole winding inductance L r2 , and the first resonant cavity energy interaction capacitor Cr1 The harmonic suppression inductor current i L and the first energy receiving pole winding inductance L r2 discharges together until its voltage drops to zero, this working mode ends.

[0042] Working mode 5: as shown in Figure 8 , when the voltage of the first resonant cavity energy interaction capacitor C r1 drops to zero, this working mode starts, at this time the first freewheeling diode D1 turns on under the condition of ZVS, under this working mode, the current of the first energy receiving pole winding inductance L r2 decreases linearly, when the current of the first energy receiving pole winding inductance L r2 drops to zero, this working mode ends, at this time the third freewheeling diode D a in the current positive double winding magnetic integrated passive resonant circuit turns off under the condition of ZCS.

[0043] Working mode 6: as shown in Figure 9 , the harmonic suppression inductor current i L flows through the first freewheeling diode D1, and the current through the double winding magnetic core mutual inductance element remains 0, the voltage of the first resonant cavity energy interaction capacitor C r1 remains at 0, when the first high frequency modulation switch tube S1 turns on, this working mode ends, thereby switching to the next working mode 1, and so on.

[0044] When the double winding magnetic core resonant type high frequency soft switching DC / AC converter works in the II quadrant (V O > 0, i L < 0) :

[0045] When the circuit works in the II quadrant, the first dynamic potential regulating power frequency switch tube Q1 in the dynamic potential equalization circuit and the second current commutation power frequency modulation switch tube Q L2 in the no bridge arm through double channel architecture main power circuit turn on, the second high frequency modulation switch tube S2 in the no bridge arm through double channel architecture main power circuit performs high frequency switching operation, and the rest of the switch tubes are all turned off. Before working mode 1, it is assumed that the second high frequency modulation switch tube S2 is turned off and the harmonic suppression inductor current i L flows through the second freewheeling diode D2, the working modes when working in this quadrant are as shown in Figures 10-15 .

[0046] Working mode 1: as shown in Figure 10 , the second high frequency modulation switch tube S2 turns on, because the second energy injection pole winding inductance L r3the current flowing through the second high-frequency modulation switch S2 will rise slowly and linearly, thus the second high-frequency modulation switch S2 turns on under ZCS condition, at this moment the current in the second freewheeling diode D2 will decrease linearly, when the current of the second high-frequency modulation switch S2 rises to the harmonic suppression inductor current i L , this working mode ends.

[0047] Working mode 2: as shown in Figure 11 , since the current of the second high-frequency modulation switch S2 has risen to the harmonic suppression inductor current i L , the second freewheeling diode D2 is off, and turns off under ZCS condition. The second energy injection pole winding inductance L r3 of the double-winding magnetic core and the second resonant cavity energy interaction capacitor C r2 start to resonate, since the existence of the second resonant cavity energy interaction capacitor C r2 , the rise of the voltage of the second freewheeling diode D2 can be considered to be slow, thus the turn-off of the second freewheeling diode D2 is ZCZVS. When the voltage of the second resonant cavity energy interaction capacitor C r2 rises to the input voltage V in , this working mode ends.

[0048] Working mode 3: as shown in Figure 12 , when the voltage of the second resonant cavity energy interaction capacitor C r2 rises to the input voltage V in , the fourth freewheeling diode D b in the negative current double-winding magnetic integrated passive resonant circuit starts to conduct, and conducts under ZVS, the voltage of the second resonant cavity energy interaction capacitor C r2 is clamped at the input voltage V in , and the total ampere turns of the second energy injection pole winding inductance L r3 and the second energy receiving pole winding inductance L r4 of the double-winding magnetic core should remain constant. When the second high-frequency modulation switch S2 turns off, this working mode ends.

[0049] Working mode 4: as shown in Figure 13 , at this moment the second high-frequency modulation switch S2 turns off under ZVS condition, however in actual situation, since the energy of the double-winding magnetic core mutual inductance element will leak to exhibit the characteristics of leakage inductance, a small voltage spike appears at the two ends of the switch, but the peak value of the spike is usually much smaller than the maximum voltage of the switch, thus the second high-frequency modulation switch S2 can also turn off under nearly ZVS condition. The ampere turns of the second energy injection pole winding inductance L r3 of the double-winding magnetic core are transferred to the second energy receiving pole winding inductance L r4 , and the second resonant cavity energy interaction capacitor Cr2 The harmonic suppression inductor current i L and the second energy receiving pole winding inductance L r4 discharges together until its voltage drops to zero, this working mode ends.

[0050] Working mode 5: as shown in Figure 14 , when the voltage of the second resonant cavity energy interaction capacitor C r2 drops to zero, this working mode starts, at this time the second freewheeling diode D2 turns on under the condition of ZVS, under this working mode, the current of the second energy receiving pole winding inductance L r4 decreases linearly, when the current of the second energy receiving pole winding inductance L r4 drops to zero, this working mode ends, at this time the fourth freewheeling diode D b in the current negative double-winding magnetic integrated passive resonant circuit turns off under the condition of ZCS.

[0051] Working mode 6: as shown in Figure 15 , the harmonic suppression inductor current i L flows through the second freewheeling diode D2, and the current through the double-winding magnetic core mutual inductance element remains 0, the voltage of the second resonant cavity energy interaction capacitor C r2 remains at 0, when the second high-frequency modulation switch tube S2 turns on, this working mode ends.

[0052] When the double-winding magnetic core resonant type high-frequency soft switching DC / AC converter works in the III quadrant (V O <0, i L <0) :

[0053] When the circuit works in the III quadrant, the second dynamic potential regulating line frequency power switch tube Q2 in the dynamic potential equalization circuit and the second current commutation line frequency modulation switch tube Q L2 in the no-bridge-arm-through double-channel architecture main power circuit turn on, the second high-frequency modulation switch tube S2 in the no-bridge-arm-through double-channel architecture main power circuit performs high-frequency switching operation, and the rest of the switch tubes are all turned off. Before working mode 1, it is assumed that the second high-frequency modulation switch tube S2 is turned off and the harmonic suppression inductor current i L flows through the second freewheeling diode D2, each working mode when working in this quadrant is shown in Figures 16-21 .

[0054] Working mode 1: as shown in Figure 16 , the second high-frequency modulation switch tube S2 turns on, because of the second energy injection pole winding inductance L r3the current flowing through the second high-frequency modulation switch S2 will rise slowly and linearly, thus the second high-frequency modulation switch S2 turns on under ZCS condition, at this moment the current in the second freewheeling diode D2 will decrease linearly, when the current of the second high-frequency modulation switch S2 rises to the harmonic suppression inductor current i L , this working mode ends.

[0055] Working mode 2: as shown in Figure 17 , since the current of the second high-frequency modulation switch S2 has risen to the harmonic suppression inductor current i L , the second freewheeling diode D2 is off, and turns off under ZCS condition. The second energy injection pole winding inductance L r3 of the double-winding magnetic core and the second resonant cavity energy interaction capacitor C r2 start to resonate, since the existence of the second resonant cavity energy interaction capacitor C r2 , the rise of the voltage of the second freewheeling diode D2 can be considered to be slow, thus the turn-off of the second freewheeling diode D2 is ZCZVS. When the voltage of the second resonant cavity energy interaction capacitor C r2 rises to the input voltage V in , this working mode ends.

[0056] Working mode 3: as shown in Figure 18 , when the voltage of the second resonant cavity energy interaction capacitor C r2 rises to the input voltage V in , the fourth freewheeling diode D b in the negative current double-winding magnetic integrated passive resonant circuit starts to conduct, and conducts under ZVS, the voltage of the second resonant cavity energy interaction capacitor C r2 is clamped at the input voltage V in , and the total ampere turns of the second energy injection pole winding inductance L r3 and the second energy receiving pole winding inductance L r4 of the double-winding magnetic core should remain constant. When the second high-frequency modulation switch S2 turns off, this working mode ends.

[0057] Working mode 4: as shown in Figure 19 , at this moment the second high-frequency modulation switch S2 turns off under ZVS condition, however in actual situation, since the energy of the double-winding magnetic core mutual inductance element will leak to exhibit the characteristics of leakage inductance, a small voltage spike appears at the two ends of the switch, but the peak value of the spike is usually much smaller than the maximum voltage of the switch, thus the second high-frequency modulation switch S2 can also turn off under nearly ZVS condition. The ampere turns of the second energy injection pole winding inductance L r3 of the double-winding magnetic core are transferred to the second energy receiving pole winding inductance L r4 , the second resonant cavity energy interaction capacitor Cr2 The harmonic suppression inductor current i L and the second energy receiving magnetic pole winding inductance L r4 discharges together until its voltage drops to zero, and this working mode ends.

[0058] Working mode 5: as shown in Figure 20 , when the voltage of the second resonant cavity energy interaction capacitor C r2 drops to zero, the second freewheeling diode D2 turns on under the condition of ZVS, and in this working mode, the current of the second energy receiving magnetic pole winding inductance L r4 linearly decreases, and when the current of the second energy receiving magnetic pole winding inductance L r4 drops to zero, the fourth freewheeling diode D b in the current negative double-winding magnetic integrated passive resonant circuit turns off under the condition of ZCS, and this working mode ends.

[0059] Working mode 6: as shown in Figure 21 , the harmonic suppression inductor current i L flows through the second freewheeling diode D2, and the current through the double-winding magnetic core mutual inductance element remains 0, and the voltage of the second resonant cavity energy interaction capacitor C r2 remains at 0, and when the second high-frequency modulation switch tube S2 turns on, this working mode ends, and thus it goes to the next working mode 1, and so on.

[0060] When the double-winding magnetic core resonant high-frequency soft switching DC / AC converter works in the IV quadrant (V O < 0, i L > 0) :

[0061] When the circuit works in the IV quadrant, the second dynamic potential regulating power frequency modulation switch tube Q2 in the dynamic potential balancing circuit and the first current commutation power frequency modulation switch tube Q L1 in the no-bridge-arm-through double-channel architecture main power circuit turn on, the first high-frequency modulation switch tube S1 in the no-bridge-arm-through double-channel architecture main power circuit performs high-frequency switching operation, and the rest of the switch tubes are all turned off. Before working mode 1, it is assumed that the first high-frequency modulation switch tube S1 is turned off and the harmonic suppression inductor current i L flows through the first freewheeling diode D1, and each working mode when working in this quadrant is as shown in Figures 22-27 .

[0062] Working mode 1: as shown in Figure 22 , the first high-frequency modulation switch tube S1 turns on, and since the first energy injection magnetic pole winding inductance L r1the current flowing through the first high-frequency modulation switch S1 will rise slowly and linearly, so the first high-frequency modulation switch S1 is turned on under ZCS condition, at this time the current in the first freewheeling diode D1 will decrease linearly, when the current of the first high-frequency modulation switch S1 rises to the harmonic suppression inductance current i L , this working mode ends.

[0063] Working mode 2: as shown in Figure 23 , since the current of the first high-frequency modulation switch S1 has risen to the harmonic suppression inductance current i L , the first freewheeling diode D1 is turned off, and is turned off under ZCS condition. The first energy injection pole winding inductance L r1 of the double-winding magnetic core and the first resonant cavity energy interaction capacitor C r1 start to resonate, since the existence of the first resonant cavity energy interaction capacitor C r1 , the rise of the voltage of the first freewheeling diode D1 can be considered to be slow, so the turn-off of the first freewheeling diode D1 is ZCZVS. When the voltage of the first resonant cavity energy interaction capacitor C r1 rises to the input voltage V in , this working mode ends.

[0064] Working mode 3: as shown in Figure 24 , when the voltage of the first resonant cavity energy interaction capacitor C r1 rises to the input voltage V in , the third freewheeling diode D a in the current forward double-winding magnetic integrated passive resonant circuit starts to conduct, and the conduction is ZVS, the voltage of the first resonant cavity energy interaction capacitor C r1 is clamped to the input voltage V in , and the total ampere turns of the first energy injection pole winding inductance L r1 and the first energy receiving pole winding inductance L r2 of the double-winding magnetic core should remain constant. When the first high-frequency modulation switch S1 is turned off, this working mode ends.

[0065] Working mode 4: as shown in Figure 25 , at this time the first high-frequency modulation switch S1 is turned off under ZVS condition, however in actual situation, since the energy of the double-winding magnetic core mutual inductance element will leak to exhibit the characteristics of leakage inductance, a small voltage spike appears at the two ends of the switch, but the peak value of the spike is usually much smaller than the maximum voltage of the switch, so the first high-frequency modulation switch S1 can also be turned off under the condition of nearly ZVS. The ampere turns of the first energy injection pole winding inductance L r1 of the double-winding magnetic core are transferred to the first energy receiving pole winding inductance L r2 , the first resonant cavity energy interaction capacitor Cr1 The harmonic suppression inductor current i L and the first energy receiving magnetic pole winding inductance L r2 is discharged together with the current until its voltage drops to zero, and the working mode ends.

[0066] Working mode 5: as shown in Figure 26 , when the voltage of the first resonant cavity energy interaction capacitor C r1 drops to zero, the first freewheeling diode D1 is turned on under the condition of ZVS, and under the working mode, the current of the first energy receiving magnetic pole winding inductance L r2 decreases linearly, and when the current of the first energy receiving magnetic pole winding inductance L r2 drops to zero, the working mode ends, and at this time, the third freewheeling diode D a in the positive current double-winding magnetic integrated passive resonant circuit is turned off under the condition of ZCS.

[0067] Working mode 6: as shown in Figure 27 , the harmonic suppression inductor current i L is freewheeled through the first freewheeling diode D1, and the current through the double-winding magnetic core mutual inductance element is kept at 0, and the voltage of the first resonant cavity energy interaction capacitor C r1 is kept at 0, and when the first high-frequency modulation switch tube S1 is turned on, the working mode ends.

[0068] As can be known from the above description, the application proposes a double-winding magnetic core resonant high-frequency soft switching DC / AC converter which can greatly reduce the switching loss of the high-frequency modulation power switch tube of the DC / AC converter, and the converter has the following advantages:

[0069] (1) The high-frequency modulation power switch tube in the proposed topology can realize soft switching, reduce switching loss, improve the overall efficiency of the converter, and can limit the influence of electromagnetic interference;

[0070] (2) The power switch tube of the proposed topology can work at a high switching frequency, which helps to reduce the size of the harmonic suppression shaping element, and soft switching can be realized with only a small number of elements, which greatly helps to improve the power density of the system;

[0071] (3) The realization of soft switching does not require additional switches for assistance, which greatly simplifies the logic of the control circuit.

[0072] (4) The main power freewheeling diode of the topology is turned off under the condition of ZV and ZCS, and the passive resonant circuit freewheeling diode is turned off under the condition of ZCS, which avoids the generation of diode reverse recovery current, so there is no reverse recovery problem.

[0073] (5) In the present application, the primary and secondary winding inductance values of each group of double-winding magnetic core mutual inductance elements are different, so the number of turns is different, thereby generating a turns ratio, defining the turns ratio n of the number of turns of the secondary and primary winding, and setting the turns ratio n of the two groups of double-winding magnetic core mutual inductance elements to be the same; due to the existence of the turns ratio of the energy injection side winding and the energy receiving side winding of the double-winding magnetic core mutual inductance element, different n will cause the amplitude of the stress reduction to be different. By selecting a suitable turns ratio, such as n>1, the voltage and current stress of the switch tube can be reduced, which is beneficial to the cost control of the converter.

[0074] The "first", "second" and the like in the names mentioned in the embodiments of the present application are only used for name identification, and do not represent the importance ranking.

[0075] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter, characterized in that, It includes a bridgeless through-dual-channel main power circuit, a current-positive dual-winding magnetically integrated passive resonant circuit, a current-negative dual-winding magnetically integrated passive resonant circuit, a dynamic potential equalization circuit, and a harmonic suppression and shaping circuit. Among them, the bridge-arm-less direct-through dual-channel main power circuit is used to suppress the positive and negative harmonic inductor current i. L Provides an adaptive main power transmission path and performs high-frequency chopping on the input voltage; the bridge-arm-less through-through dual-channel main power circuit includes a positive harmonic suppression inductor current transmission path and a negative harmonic suppression inductor current transmission path. The positive harmonic suppression inductor current transmission path includes a first high-frequency modulation switch S1 and a first current-commutating power frequency modulation switch Q. L1 The first freewheeling diode D1; the negative harmonic suppression inductor current transmission path includes the second high-frequency modulation switch S2 and the second current-commutating power frequency modulation switch Q. L2 And the second freewheeling diode D2; The current-forward dual-winding magnetically integrated passive resonant circuit is connected to the main power circuit of the bridgeless through-dual-channel architecture. It is used to create soft-switching conditions for the first high-frequency modulation switch S1 when it performs high-frequency switching operation, thereby reducing the switching loss and current and voltage stress of the high-frequency switch. The negative current dual-winding magnetically integrated passive resonant circuit is connected to the main power circuit of the bridgeless through-through dual-channel architecture. It is used to create soft switching conditions for the second high-frequency modulation switch S2 when it performs high-frequency switching operation, thereby reducing the switching loss and current and voltage stress of the high-frequency switch. The dynamic potential equalization circuit is connected to the harmonic suppression and shaping circuit to dynamically adjust the terminal potential of the harmonic suppression capacitor, so that the harmonic suppression and shaping circuit can correctly output the voltage in the appropriate direction. The harmonic suppression and shaping circuit is connected to the main power circuit of the bridgeless through-through dual-channel architecture to adjust the output voltage waveform and suppress the generation of high-frequency harmonics.

2. The dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter according to claim 1, characterized in that: The source of the first high-frequency modulation switch S1 is connected to the first current-commutated power frequency modulation switch Q. L1 The drain of the diode and the cathode of the first freewheeling diode D1 are connected, and the anode of the first freewheeling diode D1 is connected to the input power supply V. in The negative terminals of the two transistors together form a positive harmonic suppression inductor current transmission path and perform high-frequency chopping on the input voltage; the drain of the second high-frequency modulation switch S2 is connected to the second current-commutating power frequency modulation switch Q. L2 The source of the first diode is connected to the anode of the second freewheeling diode D2, and the cathode of the second freewheeling diode D2 is connected to the input power supply V. in The positive terminals together form a negative harmonic suppression inductor current transmission path and perform high-frequency chopping on the input voltage. The second current-commutating power frequency modulation switch Q... L2 The drain of the first current-commutated power frequency modulation switch Q L1 The source poles are connected.

3. The dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter according to claim 1, characterized in that: The current-forward dual-winding magnetically integrated passive resonant circuit includes a first energy-injected magnetic pole winding inductor L. r1 The first energy receiving magnetic pole winding inductance L r2 The first resonant cavity energy interaction capacitor C r1 and the third freewheeling diode D a Among them, the first energy injection magnetic pole winding inductance L r1 The first energy receiving magnetic pole winding inductance L r2 This constitutes a set of dual-winding magnetic core mutual inductance elements, with the first energy injected into the magnetic pole winding inductance L. r1 As the primary side, the inductance L of the first energy receiving magnetic pole winding r2 As the secondary side; the energy interaction capacitor C between the dual-winding magnetic core and the first resonant cavity r1 At resonance, the inductor and capacitor exchange energy reactively; the first energy is injected into the magnetic pole winding inductor L. r1 The magnetic pole synchronization terminal and the first energy receiving magnetic pole winding inductor L r2 The non-magnetic pole synchronization terminal is connected to the input power supply V. in The positive terminal, the first energy is injected into the magnetic pole winding inductor L r1 The non-magnetic pole synchronization terminal is connected to the drain of the first high-frequency modulation switch S1, and the first energy receiving magnetic pole winding inductance L r2 The magnetic pole synchronization terminal is connected to the third freewheeling diode D. a The cathode, the third freewheeling diode D a The anode is connected to the cathode of the first freewheeling diode D1, the source of the first high-frequency modulation switch S1, and the first current-commutating power frequency modulation switch Q. L1 The drain electrode, and the energy interaction capacitor C of the first resonant cavity. r1 One end is connected to the first resonant cavity energy interaction capacitor C. r1 The other end is connected to the input power supply V. in The negative electrode.

4. The dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter according to claim 1, characterized in that: The negative current dual-winding magnetic integrated passive resonant circuit includes a second energy injection magnetic pole winding inductor L. r3 The inductance L of the second energy receiving magnetic pole winding r4 The second resonant cavity energy interaction capacitor C r2 and the fourth freewheeling diode D b Among them, the inductance L of the second energy injection magnetic pole winding r3 The inductance L of the second energy receiving magnetic pole winding r4 This constitutes a set of dual-winding magnetic core mutual inductance elements, with the second energy injected into the magnetic pole winding inductance L. r3 As the primary side, the inductance L of the second energy receiving magnetic pole winding r4 As the secondary side; the energy interaction capacitor C between the dual-winding magnetic core and the second resonant cavity r2 At resonance, the inductor and capacitor exchange energy reactively; among them, the second energy is injected into the magnetic pole winding inductor L. r3 The non-magnetic pole synchronous terminal and the fourth freewheeling diode D b The anode is connected to the input power supply V. in The negative terminal, the second energy is injected into the magnetic pole winding inductor L r3 The magnetic pole synchronization terminal is connected to the source of the second high-frequency modulation switch S2, and the second energy receiving magnetic pole winding inductor L r4 The magnetic pole synchronization terminal is connected to the fourth freewheeling diode D. b The cathode, the second energy receiving magnetic pole winding inductance L r4 The non-magnetic pole synchronization terminal is connected to the anode of the second freewheeling diode D2, the drain of the second high-frequency modulation switch S2, and the second current-commutating power frequency modulation switch Q. L2 The source electrode, and the energy interaction capacitor C of the second resonant cavity. r2 One end is connected to the second resonant cavity energy interaction capacitor C. r2 The other end is connected to the input power supply V. in The positive pole.

5. A dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter according to claim 1, characterized in that: The dynamic potential equalization circuit includes a first dynamic potential regulating power frequency switch Q1 and a second dynamic potential regulating power frequency switch Q2, wherein the source of the first dynamic potential regulating power frequency switch Q1 is connected to the input power supply V. in The negative terminal of the first dynamic potential regulating power frequency switch Q1 is connected to the source of the second dynamic potential regulating power frequency switch Q2 and grounded. The drain of the second dynamic potential regulating power frequency switch Q2 is connected to the input power supply V. in The positive pole.

6. A dual-winding magnetic core resonant high-frequency soft-switching DC / AC converter according to claim 5, characterized in that: Harmonic suppression and shaping circuit includes harmonic suppression inductor L f Harmonic suppression capacitor C f Among them, the harmonic suppression inductor L f One end is connected to the second current-commutating power frequency modulation switch transistor Q. L2 The drain of the first current-commutated power frequency modulation switch Q L1 The source of the harmonic suppression inductor L f The other end is connected to the output harmonic suppression capacitor C. f At one end, the harmonic suppression capacitor C f The other end is connected to the drain of the first dynamic potential regulating power frequency switch Q1 and the source of the second dynamic potential regulating power frequency switch Q2, and grounded; harmonic suppression capacitor C f The voltage across the two terminals is the output voltage V. O .

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