Si-SiC hybrid power multi-phase interleaving H-bridge converter structure based on TCM mode and control method of Si-SiC hybrid power multi-phase interleaving H-bridge converter structure

Abstract

The invention discloses a TCM-mode-based Si-SiC hybrid power multi-phase staggered H-bridge converter structure and a control method thereof, according to the scheme, a three-phase staggered parallel topology of a two-phase low-frequency Si-IGBT bridge arm and a one-phase high-frequency SiC-MOSFET bridge arm is adopted, and a TCM control strategy is combined, so that zero voltage switching (ZVS) of a Si device is successfully realized, the switching loss is remarkably reduced, and the switching efficiency is improved. The system efficiency is greatly improved; and meanwhile, through pilot frequency interleaving and ripple compensation technologies, total output current ripples are greatly reduced, and optimal balance between system performance and manufacturing cost is realized while the power capacity of the converter is remarkably expanded and the dynamic response speed and the output electric energy quality are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power electronics, and particularly relates to a Si-SiC hybrid power multi-phase interleaved H-bridge converter structure based on a TCM mode and a control method thereof. BACKGROUND

[0002] As a core technology of energy conversion and management, power electronics technology has a profound impact on the energy utilization mode of human society. As a commonly used topology of DC-AC and AC-DC converters, the H-bridge topology is widely used in consumer electronics, new energy power generation, transportation, electric vehicles and industrial automation, and has become an important cornerstone supporting the development of modern society. With the development of the times, the performance requirements of these applications for the converter are also increasing, especially in terms of energy conversion efficiency, power device thermal stress and reliability, dynamic response capability and power capacity. Although traditional Si-based power devices such as Si-based IGBT have strong current-carrying capacity, they are limited by their high switching loss, and the dynamic response, efficiency and capacity of the converter based on Si-based power devices are difficult to further improve in coordination. Wide-bandgap semiconductor devices such as SiC-MOSFET have high switching speed and low switching loss, and their application in power electronic converters can greatly improve the dynamic response speed and energy conversion efficiency of the system, but the high cost of Si-IGBT and the reliability problems of wide-bandgap devices at the same current level greatly limit their application in high-current applications.

[0003] To fully combine and take advantage of the high current-carrying capacity of Si-IGBT and the low loss of SiC-MOSFET, people have proposed a method of mixing the two devices to achieve a compromise between the cost and performance of the converter. Among them, the dual-phase different-frequency interleaved converter based on Si / SiC hybrid half-bridge is considered to be a better choice for high-current applications. The large-capacity Si phase half-bridge is used to process the main power at a low switching frequency to reduce device loss; the small-capacity SiC phase half-bridge is used to process part of the power at a high frequency to improve the output power quality and dynamic response of the converter, achieving similar superior performance to the pure SiC two-phase interleaved system at a lower cost. However, the power capacity of the dual-phase Si / SiC different-frequency interleaved H-bridge converter is still limited, and there is a contradiction between the switching frequency of the Si phase half-bridge and the size of the filter inductor. The hard switching of Si-IGBT still introduces a large switching loss.

[0004] Therefore, in view of the above technical problems and defects, it is urgent to design and develop a Si-SiC hybrid power multi-phase interleaved H-bridge converter structure based on a TCM mode and explore its control method. SUMMARY

[0005] In order to overcome the deficiencies and difficulties existing in the prior art, the purpose of the present application is to provide a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on a TCM mode and a control method thereof, so as to improve the power capacity and further reduce the loss.

[0006] The first purpose of the present application is to provide a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on a TCM mode; and the second purpose of the present application is to provide a control method of the Si-SiC hybrid power multiphase interleaved H-bridge converter based on a TCM mode.

[0007] The first purpose of the present application is achieved in that the structure comprises at least one input DC power supply end, and a three-phase H-bridge power unit electrically connected with the input DC power supply end and composed of at least two low-frequency half-bridge arms and at least one high-frequency half-bridge arm;

[0008] One side of the three-phase H-bridge power unit is electrically connected with a filtering unit composed of at least two low-frequency filtering inductors and at least one high-frequency filtering inductor; one end of the filtering unit is connected with an output port; the other end of the output port is electrically connected with at least one output switching unit composed of a power frequency switch tube;

[0009] The two low-frequency half-bridge arms are each composed of a Si-IGBT power switch tube and work in a low-frequency switching state under a triangular current mode; and the one high-frequency half-bridge arm is composed of a SiC-MOSFET power switch tube and works in a high-frequency switching state.

[0010] Further, the midpoints of the two low-frequency half-bridge arms are respectively connected to an output node through low-frequency filtering inductors;

[0011] The midpoint of the high-frequency half-bridge arm is connected to the output node through a high-frequency filtering inductor.

[0012] Further, the output node serves as one end of a converter output; and the midpoint of the output switching unit serves as the other end of the converter output and is electrically connected with an output filtering capacitor and a load.

[0013] Further, the carrier signal phases of the two low-frequency half-bridge arms are interleaved, and the phase shift angle is 180 degrees; after two-phase low-frequency current ripples are superimposed on each other, a total low-frequency current ripple with doubled frequency and reduced amplitude is obtained.

[0014] Further, the power frequency switch tube adopts a Si-IGBT, and the switching frequency of the power frequency switch tube is synchronized with the power frequency of an output voltage, so as to convert bidirectional flowing direct current into alternating current power output, or to control the on-off of a direct current output.

[0015] A second object of the present application is achieved in that the method is applied to control the Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on the TCM mode;

[0016] The control method comprises voltage outer loop control and current inner loop control, and the power distribution of the low-frequency bridge arm and the high-frequency bridge arm is coordinated by the power distribution ratio;

[0017] The current inner loop control comprises at least one low-frequency phase current loop and at least one high-frequency phase current loop, for realizing independent or cooperative control of three-phase currents.

[0018] Further, the control process of the low-frequency phase current loop is as follows:

[0019] The three-phase total inductance current and the low-frequency phase total inductance current are sampled;

[0020] The reference value of the corresponding low-frequency phase total inductance current is generated by multiplying the total current reference value by the power distribution ratio;

[0021] The reference value of the low-frequency phase total inductance current is subtracted from the sampled low-frequency phase total inductance current, to generate a corresponding low-frequency current error signal;

[0022] The low-frequency current error signal is processed by a low-frequency current regulator, to generate a corresponding duty cycle signal of the low-frequency bridge arm;

[0023] The duty cycle signal is compared with two triangular carriers with a phase difference of 180 degrees, and combined with TCM mode control logic, to generate switching drive signals of two low-frequency half-bridge arms.

[0024] Further, the TCM mode control logic triggers the turn-on of the switching tube by detecting the zero-crossing point or negative peak point of the inductance current.

[0025] Further, the control process of the high-frequency phase current loop is as follows:

[0026] According to the input voltage, the output voltage and the low-frequency switching state, a total current variation caused by the low-frequency bridge arm switching action in a high-frequency switching period is calculated and generated;

[0027] The total current reference value is subtracted from the sampled three-phase total inductance current, to generate a corresponding total current error signal;

[0028] The total current variation is subtracted from the total current error signal, to generate a corresponding high-frequency current error signal;

[0029] The high-frequency current error signal is processed by a high-frequency current regulator, to generate a corresponding duty cycle signal of the high-frequency bridge arm;

[0030] The duty cycle signal is compared with a high-frequency triangular carrier wave to generate a corresponding high-frequency half-bridge arm switching drive signal.

[0031] The application provides a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on a TCM mode, wherein the structure comprises at least one input DC power supply end, and a three-phase H-bridge power unit electrically connected with the input DC power supply end and composed of at least two low-frequency half-bridge arms and at least one high-frequency half-bridge arm; one side of the three-phase H-bridge power unit is electrically connected with a filtering unit composed of at least two low-frequency filtering inductors and at least one high-frequency filtering inductor; one end of the filtering unit is connected with an output port; the other end of the output port is electrically connected with at least one output switching unit composed of a power-frequency switching tube; the two low-frequency half-bridge arms are both composed of Si-IGBT power switching tubes and work in a low-frequency switching state under a triangular current mode; the one high-frequency half-bridge arm is composed of a SiC-MOSFET power switching tube and works in a high-frequency switching state; and a control method of the structure is provided to solve problems of limited power capacity of an existing Si / SiC hybrid H-bridge converter, large switching loss of a low-frequency device and still room for improving efficiency.

[0032] That is, by increasing one low-frequency bridge arm and introducing TCM control, power expansion, Si device zero-voltage turn-on (ZVS) to reduce loss, and further optimization of output power quality through three-phase interleaved parallel connection are realized. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0034] Figure 1 It is a schematic diagram of the Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on the TCM mode.

[0035] Figure 2 It is a schematic diagram of the principle structure of TCM current mode ZVS realization of the Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on the TCM mode.

[0036] Figure 3 It is a schematic diagram of commutation of TCM current mode ZVS realization of the Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on the TCM mode.

[0037] Figure 4A Si phase low frequency staggered half bridge TCM mode control schematic diagram based on a carrier phase shift of a Si-SiC hybrid power multiphase staggered H bridge converter structure based on a TCM mode;

[0038] Figure 5 A current simulation schematic diagram of a TCM mode Si / SiC hybrid power three phase different frequency staggered H bridge converter of a Si-SiC hybrid power multiphase staggered H bridge converter structure based on a TCM mode. DETAILED DESCRIPTION

[0039] In order to better understand the purpose, technical scheme and advantages of the present application, the present application is further described below in combination with the drawings and specific embodiments, and other advantages and effects of the present application can be easily understood by those skilled in the art from the content disclosed in the present description.

[0040] The present application can also be implemented or applied through other different specific examples, and various modifications and changes can be made to the details in the present description based on different views and applications without departing from the spirit of the present application.

[0041] It should be noted that if the present application embodiments involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications also change accordingly.

[0042] In addition, if the present application embodiments involve descriptions of “first”, “second”, etc., the descriptions of “first”, “second”, etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by “first”, “second” can explicitly or implicitly include at least one of the features. Secondly, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of a person skilled in the art, and when the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0043] The present application is further described below in combination with the drawings.

[0044] As Figures 1-3 shown, a Si-SiC hybrid power multiphase staggered H bridge converter structure based on a TCM mode is provided, wherein the structure comprises: an input direct current power supply (V IN), a three-phase H-bridge power unit composed of two low-frequency half-bridge arms and one high-frequency half-bridge arm, a filter unit composed of two low-frequency filter inductors (L1, L2) and one high-frequency filter inductor (L3), an output switching unit composed of a power frequency switch tube (S0, S_0), and an output end (V OUT );

[0045] The two low-frequency half-bridge arms are each composed of a Si-IGBT power switch tube (S L1 , S L_1 , S L2 , S L_2 ) and work in a low-frequency switching state under a triangular current mode (TCM);

[0046] The one high-frequency half-bridge arm is composed of a SiC-MOSFET power switch tube (S H , S_ H ) and works in a high-frequency switching state; the midpoints of the two low-frequency half-bridge arms are connected to an output node (A) through low-frequency filter inductors (L1, L2), and the midpoint of the high-frequency half-bridge arm is connected to the output node (A) through a high-frequency filter inductor (L3);

[0047] The output node (A) serves as one end of the converter output, and the midpoint of the output switching unit serves as the other end of the converter output, connected to an output filter capacitor (C OUT ) and a load.

[0048] The carrier signal phases of the two low-frequency half-bridge arms are staggered by 180 degrees, so that the two-phase low-frequency current ripples are superimposed on each other to obtain a total low-frequency current ripple with doubled frequency and reduced amplitude.

[0049] The control method includes voltage outer loop control and current inner loop control, and coordinates the power distribution of the low-frequency bridge arms and the high-frequency bridge arm through a power distribution ratio (K);

[0050] The current inner loop control includes a low-frequency phase current loop and a high-frequency phase current loop, realizing independent or collaborative control of three-phase current.

[0051] The power frequency switch tube (S0, S_0) adopts Si-IGBT, and its switching frequency is synchronized with the power frequency of the output voltage, used for converting bidirectional flowing direct current into alternating current power output, or for on-off control of direct current output.

[0052] Specifically, in the embodiment of the present application, the topology structure of the Si / SiC hybrid power three-phase different-frequency staggered H-bridge converter is as shown in Figure 1 The two low-frequency staggered bridge arms (switches S L1 , S L_1 , S L2, S L_2 , a high-frequency bridge arm (switches S H , S H , and power frequency switches S0 and S0. LS The input voltage is connected to the midpoint of the low-frequency bridge arm and the high-frequency bridge arm, respectively connected to the low-frequency inductors (L1 and L2) and the high-frequency inductor L3, and the two ends of the low-frequency phase and the high-frequency phase are connected in parallel and then connected to one end of the output port, and the other end of the output port is connected to the midpoint of the switches S0 and S0. When the converter is in light load operation, the high-frequency bridge arm processes all the power in high frequency, ensuring the output power quality and light load efficiency of the converter. When the converter is in medium load or heavy load operation, the two Si-phase bridge arms process the main power in low frequency, so that the low-frequency switches work in TCM current mode, and the upper and lower switches of the low-frequency bridge arm can realize ZVS turn-on, further reducing the turn-on loss, and the two-phase switches use phase-shifted carrier wave, and the total current ripple after the two-phase interleaving is still large but smaller than each phase, and the SiC-phase bridge arm processes the remaining small part of the power while compensating the ripple in high frequency, greatly reducing the total current ripple of the three-phase and improving the spectral characteristics and power quality of the total current.

[0053] To achieve the purpose of the application, a control method of the Si-SiC hybrid power multi-phase interleaved H-bridge converter structure based on the TCM mode is also provided.

[0054] The control method includes voltage outer loop control and current inner loop control, and the power distribution ratio (K) is used to coordinate the power distribution of the low-frequency bridge arm and the high-frequency bridge arm; the current inner loop control includes a low-frequency phase current loop and a high-frequency phase current loop, which realizes independent or cooperative control of the three-phase current.

[0055] The control process of the low-frequency phase current loop is as follows:

[0056] Sample the three-phase total inductor current (I LS ) and the low-frequency phase total inductor current (I LLS );

[0057] Multiply the total current reference value (I Lr ) by the power distribution ratio (K) to obtain the reference value of the low-frequency phase total inductor current;

[0058] Subtract the reference value of the low-frequency phase total inductor current from the sampled low-frequency phase total inductor current (ILLS) to obtain the low-frequency current error signal (I LLerr );

[0059] After the low-frequency current error signal (I LLerr ) is processed by the low-frequency current regulator, the duty cycle signal (D_L) of the low-frequency bridge arm is obtained.

[0060] The duty cycle signal (D_L) is compared with two-phase staggered 180-degree triangular carrier wave, and combined with TCM mode control logic to generate the switching drive signal of two low-frequency half-bridge arms.

[0061] The TCM mode control logic triggers the turn-on of the switching tube by detecting the zero-crossing point or negative peak point of the inductor current (ZCD signal), ensuring that there is a negative flow stage in each switching cycle, thereby creating zero-voltage switching (ZVS) conditions for the Si-IGBT switching tube of the low-frequency bridge arm.

[0062] The control process of the high-frequency phase current loop is as follows: according to the input voltage (V IN ), the output voltage (V OUT ) and the low-frequency switching state, the total current change (ΔI LL ) caused by the low-frequency bridge arm switching in a high-frequency switching cycle is calculated;

[0063] The total current reference value (I Lr ) is subtracted from the sampled three-phase total inductor current (I LS ) to obtain the total current error signal;

[0064] The total current change (ΔI LL ) is subtracted from the total current error signal to obtain the high-frequency current error signal (I LHerr );

[0065] The high-frequency current error signal (I LHerr ) is processed by the high-frequency current regulator to obtain the duty cycle signal (D_L) of the high-frequency bridge arm;

[0066] The duty cycle signal (D_L) is compared with the high-frequency triangular carrier wave to generate the switching drive signal of the high-frequency half-bridge arm.

[0067] The power distribution ratio (K) is dynamically adjusted according to the load size:

[0068] Under light load conditions, the power distribution ratio (K≈0) is set to make most or all of the power handled by the high-frequency SiC phase bridge arm to optimize light load efficiency;

[0069] Under medium and heavy load conditions, the power distribution ratio (K>0) is set to make most of the power handled by the two low-frequency Si phase bridge arms and a small part of the power handled by the high-frequency SiC phase bridge arm to compensate for the low-frequency phase current ripple and improve the dynamic response of the system.

[0070] The converter topology can be expanded to a multi-phase hybrid interleaved parallel structure containing more low-frequency half-bridge arms and / or high-frequency half-bridge arms.

[0071] Specifically, in this embodiment of the invention, the control section employs a dual closed-loop interleaved control of voltage and current. By adjusting the power distribution ratio K, the free distribution of current between the Si-phase low-frequency interleaved bridge arms and the SiC-phase high-frequency bridge arms can be achieved. The total three-phase current I... LS Low-frequency inductor total current I LLS The input voltage V is the current sampling signal. IN Output voltage V OUT As a voltage sampling signal, the reference value of the low-frequency current is derived from the total current reference value I. Lr The product of the power distribution ratio K and the low-frequency inductor current is calculated. The difference between this and the total low-frequency inductor current is used to obtain the low-frequency inductor current error I. LLerr The duty cycle is calculated by the low-frequency current regulator and compared with the phase-shifted carrier wave. The TCM mode control module then generates the Si-phase switching signal. The change in Si-phase current within the high-frequency cycle can be calculated by reducing the order of the input voltage, output voltage, and low-frequency switching signal. Subtracting this from the error in the total inductor current yields the high-frequency inductor current error I. LHerr The high-frequency current regulator calculates the duty cycle and compares it with the high-frequency triangular carrier wave to obtain the switching signal.

[0072] like Figure 2 and Figure 3 The diagram shows the schematic of ZVS implemented in TCM current mode, illustrating the principle of ZVS implementation, namely the commutation transition time t. s1 Internally, the parasitic capacitance of the upper transistor discharges, reducing the voltage across the upper transistor to zero. At this point, the upper transistor turns on, achieving ZVS turn-on. During the commutation transition time t... s1 Inside, because the inductor current is reversed at this time (flowing from the load end to the power supply end), the parasitic capacitance of the lower transistor discharges, causing the voltage across the lower transistor to drop to zero. At this time, the lower transistor turns on, realizing ZVS turn-on of the lower transistor.

[0073] like Figure 4 As shown, a carrier phase-shift based Si-phase low-frequency interleaved half-bridge TCM mode control method is presented, with output voltage V OUT Low-frequency inductor total current I LLS As a feedback signal, the transformed value is compared with the reference value, and then the low-frequency bridge arm duty cycle is calculated by PI control. The inputs to the master-slave phase control unit are compared with the master and slave phase carrier signals respectively. The slave phase carrier signal lags the master phase by half a low-frequency switching cycle, thus achieving interleaved current ripples between the master and slave phases. The ZCD signal and the duty cycle comparison signal are output as the Si phase half-bridge switching signal after passing through the SR flip-flop. The ZCD signal is a negative peak current detection signal, which promptly sets the upper transistor switching signal to 1 at the negative peak of the two-phase current to ensure the implementation of two-phase inductor current TCM mode control.

[0074] like Figure 5The current simulation diagram of the Si / SiC hybrid power three-phase different-frequency interlaced H-bridge converter in the TCM mode is shown. LL The high-frequency phase current I LH The total current I L The low-frequency main phase current and the low-frequency slave phase current both have negative peaks, ZVS of the switch tube can be realized, and the switching loss is reduced.

[0075] The application provides a Si-SiC hybrid power multi-phase interlaced H-bridge converter structure based on a TCM mode, wherein the structure comprises at least one input DC power supply end, and a three-phase H-bridge power unit electrically connected with the input DC power supply end and composed of at least two low-frequency half-bridge arms and at least one high-frequency half-bridge arm; one side of the three-phase H-bridge power unit is electrically connected with a filtering unit composed of at least two low-frequency filtering inductors and at least one high-frequency filtering inductor; one end of the filtering unit and an output port are connected; the other end of the output port is electrically connected with at least one output switching unit composed of a power-frequency switch tube; the two low-frequency half-bridge arms are both composed of Si-IGBT power switch tubes and work in a low-frequency switching state under a triangular current mode; the one high-frequency half-bridge arm is composed of a SiC-MOSFET power switch tube and works in a high-frequency switching state; and a control method of the structure is provided to solve the problems of limited power capacity of an existing Si / SiC hybrid H-bridge converter, large switching loss of a low-frequency device, and still room for improving efficiency.

[0076] That is, by adding a low-frequency bridge arm and introducing TCM control, power expansion, Si device zero voltage switching (ZVS) to reduce loss, and further optimization of output power quality through three-phase interlaced parallel connection are realized.

[0077] In other words, the scheme of the present application successfully realizes zero voltage switching (ZVS) of Si devices by adopting a three-phase interleaved parallel topology of two-phase low-frequency Si-IGBT bridge arms and one-phase high-frequency SiC-MOSFET bridge arms, combining with a TCM control strategy, significantly reduces switching loss, and greatly improves system efficiency; at the same time, through the technology of different frequency interleaving and ripple compensation, the total output current ripple is greatly reduced, while significantly expanding the power capacity of the converter, improving the dynamic response speed and the output power quality, the optimal balance of system performance and manufacturing cost is realized.

[0078] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode, characterized in that, The structure includes at least one input DC power supply terminal, and a three-phase H-bridge power unit electrically connected to the input DC power supply terminal and consisting of at least two low-frequency half-bridge arms and at least one high-frequency half-bridge arm. One side of the three-phase H-bridge power unit is electrically connected to a filter unit consisting of at least two low-frequency filter inductors and at least one high-frequency filter inductor; the filter unit is connected to one end of the output port; the other end of the output port is electrically connected to at least one output switching unit consisting of a power frequency switching transistor. Both low-frequency half-bridge arms are composed of Si-IGBT power switches and operate in low-frequency switching state under triangular current mode; the high-frequency half-bridge arm is composed of SiC-MOSFET power switches and operates in high-frequency switching state.

2. The Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 1, characterized in that, The midpoints of the two low-frequency half-bridge arms are respectively connected to the output node through low-frequency filter inductors; The midpoint of the high-frequency half-bridge arm is connected to the output node via a high-frequency filter inductor.

3. The Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 2, characterized in that, The output node serves as one end of the converter output; the midpoint of the output switching unit serves as the other end of the converter output, and is electrically connected to the output filter capacitor and the load.

4. A Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 1 or 2, characterized in that, The carrier signals of the two low-frequency half-bridge arms are phase-interleaved with a phase shift angle of 180 degrees. The two low-frequency current ripples are superimposed to obtain a total low-frequency current ripple with doubled frequency and reduced amplitude.

5. The Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 1, characterized in that, The power frequency switching transistor is a Si-IGBT, and its switching frequency is synchronized with the power frequency of the output voltage. It is used to convert bidirectional DC-DC power into AC power output, or to control the on / off state of DC output.

6. A control method for a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode, characterized in that, The method is applied to control the Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode as described in any one of claims 1-4; The control method includes voltage outer loop control and current inner loop control, and coordinates the power distribution between the low-frequency bridge arm and the high-frequency bridge arm through the power distribution ratio. The current inner loop control includes at least one low-frequency phase current loop and at least one high-frequency phase current loop, used to achieve independent or coordinated control of the three-phase currents.

7. The control method for a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 6, characterized in that, The control process of the low-frequency phase current loop is as follows: Sample the total inductance current of the three phases and the total inductance current of the low-frequency phases; The reference value of the low-frequency phase total current is generated by multiplying the total current reference value by the power allocation ratio; The reference value of the total low-frequency phase current is subtracted from the sampled total low-frequency phase inductance current to generate a corresponding low-frequency current error signal. The low-frequency current error signal is processed by a low-frequency current regulator to generate a corresponding low-frequency bridge arm duty cycle signal. The duty cycle signal is compared with two triangular carrier waves that are 180 degrees out of phase, and combined with the TCM mode control logic, corresponding switching drive signals for the two low-frequency half-bridge arms are generated.

8. The control method for a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 7, characterized in that, The TCM mode control logic triggers the switching transistor to turn on by detecting the zero-crossing point or negative peak point of the inductor current.

9. The control method for a Si-SiC hybrid power multiphase interleaved H-bridge converter structure based on TCM mode according to claim 6, characterized in that, The control process of the high-frequency phase current loop is as follows: Based on the input voltage, output voltage, and low-frequency switching state, the total current change caused by the low-frequency bridge arm switching action within a high-frequency switching cycle is calculated and generated. The total current reference value is subtracted from the sampled three-phase total inductance current to generate a corresponding total current error signal; The total current change is subtracted from the total current error signal to generate a corresponding high-frequency current error signal; The high-frequency current error signal is processed by a high-frequency current regulator to generate the corresponding high-frequency bridge arm duty cycle signal. The duty cycle signal is compared with a high-frequency triangular carrier wave to generate a corresponding high-frequency half-bridge arm switching drive signal.

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