Bipolar self-balancing interleaved coupled inductor high gain converter for dc microgrid

Abstract

The application discloses a bipolar self-balancing interleaved coupled inductor high-gain converter for a direct-current microgrid, relates to the field of boost converters, and utilizes the winding ratio boost characteristic of the interleaved coupled inductor and the voltage superposition effect of the multi-stage diode-capacitor voltage doubling network to realize high-gain output and power expansion, adopts the mixed method of the voltage doubling network and the switched capacitor network on the output side to improve the output voltage, and through the organic combination of the interleaved coupled inductor structure and the voltage doubling network and the switched capacitor network, a high boost ratio can be obtained under the condition of a lower duty cycle and a smaller coupled inductor winding ratio, the problems of increased leakage inductance, high magnetic core loss and excessive device stress caused by the dependence of traditional topologies on an extremely high duty cycle or an ultra-large winding ratio are avoided, the boost capability under a wide input voltage range is significantly improved, and the bipolar self-balancing interleaved coupled inductor high-gain converter is suitable for the scene of supplying power from low-voltage new energy such as photovoltaic energy and energy storage to a high-voltage direct-current bus.

Description

Technical Field

[0001] This application relates to the field of boost converters, and in particular to a bipolar self-balancing interleaved coupled inductor high-gain converter for DC microgrids. Background Technology

[0002] With the development of photovoltaic power generation, energy storage systems, electric vehicles, and high-voltage direct current (HVDC) transmission technology, the demand for supplying power from low-voltage DC energy to high-voltage DC buses is increasing. Photovoltaic modules, fuel cells, and low-voltage energy storage batteries typically output low-voltage DC power ranging from tens to hundreds of volts, while downstream inverters, high-voltage DC buses, and industrial drive systems often require DC voltages of hundreds or even thousands of volts. Therefore, high-gain DC-DC boost converters are needed to achieve energy conversion.

[0003] Traditional Boost converters have a simple structure, but their voltage gain is limited by the duty cycle. To obtain a larger gain, a larger duty cycle is required. However, when the duty cycle is close to 1, the voltage and current stress on the switching transistors and diodes increases significantly, the system conduction loss and switching loss rise sharply, and the efficiency decreases significantly. Therefore, it is difficult to meet the requirements of high-gain scenarios.

[0004] To improve the boost converter's boost capability, existing technologies have proposed various high-gain converter topologies, such as interleaved boost converters, coupled inductor boost converters, and switched capacitor voltage doubler boost converters: (1) Interleaved boost converters can reduce input current ripple and improve input current continuity. However, traditional interleaved structures usually require strict phase shift control to effectively reduce input ripple. (2) Coupled inductor boost converters can increase voltage gain by utilizing turns ratio, but to obtain higher voltage gain, a larger coupled inductor turns ratio is required, which leads to increased leakage inductance and core loss. In addition, some topologies use multi-winding coupled inductor structures, resulting in poor winding parameter consistency and easy output imbalance. Moreover, the actual secondary voltage of the coupled inductor is lower than the theoretical value, leading to a large deviation between the theoretical gain and the actual output. (3) Switched capacitor voltage doubler boost converters can achieve high output voltage under low duty cycle conditions, but the diode and capacitor voltage stress in the voltage doubler structure is high.

[0005] In summary, existing high-gain converters typically require higher duty cycles or larger turns ratios to achieve higher output voltages, leading to increased voltage stress and conduction losses in the devices. Furthermore, all current multiphase structures suffer from bipolar voltage imbalance in their upper and lower branches, resulting in power imbalance that affects system stability and efficiency, making them unsuitable for bipolar DC microgrids. Additionally, in all bipolar multiphase structures, the input power supply ground cannot share a common ground with the bipolar neutral point, failing to suppress leakage current from the photovoltaic panels. Summary of the Invention

[0006] This application addresses the aforementioned problems and technical requirements by proposing a bipolar self-balancing interleaved coupled inductor high-gain converter for DC microgrids. The technical solution of this application is as follows: A bipolar self-balancing interleaved-coupled inductor high-gain converter for DC microgrids, wherein: DC input source V in The positive terminal is simultaneously connected to the primary winding of the first set of coupled inductors. L The same-name terminal of 1 and the primary winding of the second set of coupled inductors L The same terminal of 2, DC input source V in The negative terminal is grounded; The primary winding of the first group of coupled inductors L 1. The non-same-name terminal is connected to the main switch transistor. S The drain of 1, the primary winding of the second set of coupled inductors L 2. The non-same-name terminal is connected to the main switch transistor. S 2's drain, main switch transistor S 1's source and main switch transistor S The sources of transistor 2 are grounded together; the main switch transistor S The gate of transistor 1 is connected to the first drive signal, and the main switch transistor is... S The gate of 2 is connected to the second drive signal. The phase difference between the first drive signal and the second drive signal causes the main switch transistor to... S 1 and main switch transistor S 2. Interleaved work; The first group of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L The non-identical terminals of the 4-phase inductor are connected in series, and the first group of coupled inductor secondary windings... L 3. Second group of coupled inductor secondary winding L The terminals of 4 are connected to a voltage multiplier network with an embedded switched capacitor network. The voltage multiplier network with the embedded switched capacitor network includes multiple voltage multiplier structures connected in series. The first-stage voltage multiplier structure has an embedded switched capacitor network. The first-stage voltage multiplier structure with the embedded switched capacitor network is connected between the primary and secondary windings of the two sets of coupled inductors. The last-stage voltage multiplier structure is connected to the load. R .

[0007] A further technical solution involves a first-stage voltage multiplier structure embedded with a switched capacitor network, including a diode. D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 Auxiliary switching transistorS 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Each auxiliary diode includes a body diode: diode D 1 Anode and diode D The cathodes of 2 are all connected to the primary winding of the first set of coupled inductors. L The non-identical terminal of 1, diode D 1 Cathode connected capacitor C The positive electrode of 1 and the structure used to connect to the subsequent voltage multiplier; capacitance C 1. Negative terminal, capacitor C 21 Positive electrode, auxiliary switching transistor S The sources of 5 are all connected to the primary winding of the second set of coupled inductors. L The non-same-name terminals of 2 and the secondary winding of the first set of coupled inductors L The same name end of 3; capacitance C 21 The negative terminals are respectively connected to the auxiliary switching transistors. S 3's drain and auxiliary switching transistor S 4 drain, auxiliary switching transistor S 4's source is connected to the auxiliary switch. S The drain of capacitor C5 and the positive terminal of capacitor C22; diode D The anodes of 2 are connected to capacitors respectively. C 22 negative electrode, auxiliary switching transistor S The source of 3 and the structure used to connect to the subsequent voltage multiplier; Among them, diode D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 This constitutes the first-stage voltage multiplier structure; diode D 2. Capacitor C 21 ,capacitance C 22 Composition of main switching transistor S Clamping circuit of 1; auxiliary switching transistor S 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Capacitors C 21 ,capacitance C 22 Construct a switched capacitor network and use it as the main switch transistor S2. Clamping circuit.

[0008] A further technical solution is that the voltage multiplier network also includes a second-stage voltage multiplier structure and a third-stage voltage multiplier structure; the second-stage voltage multiplier structure includes a diode. D 3. Diode D 4. Capacitor C 3. Capacitor C 4; The third-stage voltage multiplier structure includes diodes. D 5. Diode D 6. Output capacitor C 5. Output capacitor C 6; In the second-stage voltage multiplier structure, the diode D The anode of 3 is connected to the diode in the first-stage voltage multiplier structure. D 1. Cathode, diode D 3 Cathode connected capacitor C The diode in the positive electrode and the third stage voltage multiplier structure of 3 D 5's anode; capacitor C 3. The negative terminal is connected to the capacitor. C 4's positive terminal and the second set of coupled inductor secondary windings L 4's corresponding terminals; capacitor C The negative terminal of 4 is connected to the diode. D The diode in the anode and third-stage voltage multiplier structure of 4 D 6 cathode; diode D The cathode of the 4-stage diode is connected to the first-stage voltage multiplier structure. D 2's anode; In the third-stage voltage multiplier structure, the diode D 5 Cathode connected to output capacitor C 5's positive electrode and load R The positive terminal; the output capacitor C The negative terminal of 5 is connected to the output capacitor. C The positive terminals of 6 are grounded together, and the output capacitor... C The negative terminal of 6 is connected to the diode. D 6 Anode and load R The negative electrode.

[0009] A further technical solution is that, within one switching cycle of the bipolar self-balancing interleaved coupled inductor high-gain converter: exist t 0 o'clock to t In a single moment, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the off state under the second drive signal; exist t 1 hour to tBetween 2 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second drive signal; exist t 2 o'clock to t Between 3 moments, the main switch transistor S 1. Main switch transistor is in the off state under the first drive signal. S 2 is in the on state under the second drive signal; exist t 3 o'clock to t Between 4 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second drive signal; The duty cycle D1 of the first driving signal is equal to or unequal to the duty cycle D2 of the second driving signal, and the phase difference between the first driving signal and the second driving signal is related to the ripple magnitude.

[0010] A further technical solution is to improve the voltage gain of a bipolar self-balancing interleaved coupled inductor high-gain converter. M for:

[0011] in, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L 3. Coupling turns ratio, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L The coupling coefficient of 3; It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L 4. Coupling turns ratio It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L The coupling coefficient is 4. It is the duty cycle of the first drive signal. It is the duty cycle of the second drive signal.

[0012] Its further technical solution is an output capacitor. C 5 voltage and output capacitor C 6 voltage The expression is:

[0013]

[0014] in, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L 3. Coupling turns ratio, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L The coupling coefficient of 3; It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L 4. Coupling turns ratio It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L The coupling coefficient is 4. It is the main switching transistor S When 1 is turned on, the primary winding of the first set of coupled inductors L 1 voltage, It is the main switching transistor S 1. When turned off, the primary winding of the first set of coupled inductors L 1 voltage and ; It is the main switching transistor S When 2 is turned on, the primary winding of the second set of coupled inductors L 2 voltage, It is the main switching transistor S When 1 is turned off, the primary winding of the second set of coupled inductors L 2 voltage; It is a capacitor C 1 voltage and ; It is a capacitor C 3 voltage and ; It is a capacitor C 4 voltage and ; It is a capacitor C 21 voltage, It is a capacitor C 22 The voltage, and ; When the duty cycle D1 of the first drive signal is equal to the duty cycle D2 of the second drive signal, the output capacitor... C 5 voltage and output capacitor C 6 voltage Equal, the bipolar self-balancing interleaved coupled inductor high-gain converter achieves voltage equalization function.

[0015] A further technical solution involves a bipolar self-balancing interleaved coupled inductor high-gain converter where one switching cycle comprises seven sequentially occurring modes: First mode: Main switching transistor S 1. Main switch transistor remains on under the first drive signal. S 2 is turned off under the second drive signal and stored in the primary winding of the second set of coupled inductors. L Energy in 2 is transferred to the capacitor. C 21 and capacitor C 22 Above, capacitor C 21 and capacitor C 22 Parallel charging; main switching transistor S The voltage stress of 2 is clamped by the parallel network of capacitors; capacitors C 4. Discharge to capacitor C 21 and capacitor C 22 The capacitor parallel network and the output capacitor C 6. Charging; First group of coupled inductor secondary winding L 3. Second group of coupled inductor secondary winding L 4 via diode D 3. Freewheeling capacitor C 3. Charging; Second mode: Main switching transistor S 1 is in the ON position under the first drive signal, and the main switch transistor is ON. S 2 is in the conducting state under the second driving signal, diode D 6 remains conductive due to the capacitor. C 4. Second group of coupled inductor secondary winding L 4. The first set of coupled inductor secondary windings L 3. Main switch transistor S 2. Output capacitor C 6. Diode D The circuit consisting of 6 elements still contains current. Third mode: Main switching transistor S 1. Turn off under the first drive signal, main switch transistor S 2. The diode continues to be in the conducting state under the second driving signal. D 1. Diode D 6 is turned on, and part of the energy is stored in the primary winding of the first set of coupled inductors. L Energy in 1 is transferred to the capacitor. C 1 and through diode D 1. Main switch transistor S The voltage stress of 1 is clamped to the capacitor. C voltage of 1V C1 With the main switch transistor S The voltage stresses of the two are not equal; the secondary windings of the first set of coupled inductors L 3. Second group of coupled inductor secondary winding L 4 and capacitor C 4. Connected in series to provide output capacitor C 6. Charging, thereby increasing voltage gain; Fourth mode: Main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The diode remains on under the second drive signal. D 4. Conducting, capacitor C 21 and capacitor C 22 Series discharge, to the capacitor C 4. Charging, with capacitor C The charging path of 3 is asymmetrical; DC input source V in The first group of coupled inductor primary windings L 1. Capacitor C 1. Capacitor C 3. Series connection to the output capacitor C 5. Charging; Fifth mode, main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The first set of coupled inductor primary windings remains on under the second drive signal. L 1. Energy release complete, main switch transistor S 1. Achieving zero-current conduction to improve converter efficiency; diodes D 1. Shutdown, from DC input source V in The second set of coupled inductor primary windings L 2. The first set of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L 4. Capacitor C 3. Diode D 5. Output capacitor C The circuit consisting of 5 components still has current flowing through it, supplying the output capacitor. C 5. Charging; Sixth mode: Main switch transistor S 1. Turns on under the first drive signal, main switch transistor S 2. Continues to be in the conducting state under the second drive signal; DC input source V in For the primary winding of the first set of coupled inductors L 1. Second group of coupled inductor primary windingL 2. Energy storage; First set of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L The current in diode 4 gradually decreases. When the current decreases to zero, the diode... D 4. Diode D 5. Zero-current shutdown; Seventh mode: Main switch transistor S 1. Turns on under the first drive signal, main switch transistor S 2. Under the second drive signal, the diodes remain in the conducting state, and all diodes are in the reverse bias state. During this period, the primary winding of the first set of coupled inductors... L 1. Second group of coupled inductor primary winding L 2. From DC input source V in Linear charging.

[0016] A further technical solution is that when the bipolar self-balancing interleaved coupled inductor high-gain converter is in the first mode, when the main switch transistor... S 2. When the circuit is just turned off, the primary winding of the second set of coupled inductors L The leakage current of 2 passes through the auxiliary switching transistor. S The 4-pin body diode is running, and the main switching transistor is also running. S The voltage stress of 2 is twice that of the capacitance. C 21 It is the main switch transistor. S Twice the voltage stress of 1.

[0017] A further technical solution is that the first driving signal and the second driving signal are in t 1 hour to t The phases that alternate between two time points are: Phase shift angle The minimum current ripple is determined by the compensation of the ripples of the two-phase input currents.

[0018] A further technical solution is that when the duty cycle D1 of the first driving signal is not equal to the duty cycle D2 of the second driving signal, the difference between the duty cycles D1 and D2 is caused by the output capacitance due to the parasitic parameters of the coupling inductor. C 5 and output capacitor C The voltage difference between 6 is determined by feedback.

[0019] The beneficial technical effects of this application are: This application discloses a bipolar self-balancing interleaved-coupled inductor high-gain converter for DC microgrids. This converter utilizes the turns ratio boosting characteristic of interleaved-coupled inductors and the voltage superposition effect of multi-stage diode-capacitor voltage multiplier networks to achieve high-gain output and power expansion. On the output side, a hybrid method of voltage multiplier network and switched capacitor network is used to improve the output voltage. Through the organic combination of interleaved-coupled inductor structure with voltage multiplier network and switched capacitor network, a high boost ratio can be obtained under conditions of low duty cycle and small coupled inductor turns ratio. This avoids the problems of increased leakage inductance, high core loss and excessive device stress caused by traditional topologies that rely on extremely high duty cycle or ultra-large turns ratio. It significantly improves the boost capability under a wide input voltage range and is suitable for scenarios where low-voltage new energy sources such as photovoltaics and energy storage supply power to high-voltage DC buses.

[0020] This converter uses two sets of coupled inductors operating alternately. The phase difference between the two main switches is no longer 180°, but is adjusted according to the ripple magnitude, thereby significantly reducing input current ripple, improving input current continuity, reducing the impact on the front-end power supply, and enhancing system stability and electromagnetic compatibility.

[0021] This converter effectively suppresses the voltage stress on the main switch, diodes, and capacitors by using clamping circuits with different coupling inductor voltages and voltage division through a voltage multiplier network, thus avoiding overvoltage problems in multi-stage voltage multiplier structures. At the same time, multiple diodes achieve zero-current turn-off (ZCS) during converter operation, and both the main switch S1 and the diodes are in a soft-switching state, significantly reducing switching losses and conduction losses and improving overall conversion efficiency.

[0022] The converter's circuit topology inherently possesses self-equalizing voltage characteristics. It achieves automatic output voltage equalization by using the series-shared secondary windings of two sets of coupled inductors. The output capacitor voltage is only related to the input voltage, the turns ratio of the coupled inductors, and the duty cycle, and is independent of the load size and power imbalance. No additional closed-loop control or compensation circuit is required. It can maintain stable output voltage under load changes and two-phase power imbalance conditions, enhancing the system's adaptability to load disturbances.

[0023] This converter uses only two sets of two-winding coupled inductors, replacing the traditional multi-winding coupled inductor scheme. Because the secondary windings of the two coupled inductors are shared in series, voltage imbalances caused by parasitic parameters are shared by the two output capacitors, thus eliminating voltage differences caused by parasitic parameters. Therefore, no additional complex design methods are required. Furthermore, the fewer windings and simpler winding process effectively avoid output imbalance problems caused by inconsistent parasitic parameters in multiple windings. The parasitic parameter effects of the coupled inductors are shared by the circuit, ensuring parameter consistency without special winding processes, reducing design and manufacturing difficulty.

[0024] The converter's two-phase branches can withstand unbalanced power operation, and the neutral point currents can partially cancel each other out, reducing losses and further optimizing efficiency. Simultaneously, the input and output neutral points share a common ground, eliminating EMI and EMC issues. This common grounding also allows for short-circuiting of the photovoltaic panel's parasitic capacitance when connected to a grid-connected inverter, eliminating leakage current from the photovoltaic panel. Furthermore, rapid isolation via switching transistors in case of power supply anomalies enhances system safety and adapts to complex application scenarios such as dual DC bus power supply. Attached Figure Description

[0025] Figure 1 This is a circuit diagram of a bipolar self-balancing interleaved coupled inductor high-gain converter in one embodiment of this application.

[0026] Figure 2 This is a timing waveform diagram of the drive signals of two main switching transistors in one embodiment of this application, and a current waveform diagram of the primary windings in two sets of coupled inductors.

[0027] Figure 3 This is a schematic diagram of the current flow of a bipolar self-balancing interleaved coupled inductor high-gain converter in the first mode, according to one embodiment of this application.

[0028] Figure 4 This is a schematic diagram of the current flow of a bipolar self-balancing interleaved coupled inductor high-gain converter in the second mode in one embodiment of this application.

[0029] Figure 5 This is a schematic diagram of the current flow in the third mode of a bipolar self-balancing interleaved coupled inductor high-gain converter in one embodiment of this application.

[0030] Figure 6 This is a schematic diagram of the current flow of a bipolar self-balancing interleaved coupled inductor high-gain converter in the fourth mode in one embodiment of this application.

[0031] Figure 7 This is a schematic diagram of the current flow of a bipolar self-balancing interleaved coupled inductor high-gain converter in the fifth mode in one embodiment of this application.

[0032] Figure 8 This is a schematic diagram of the current flow of a bipolar self-balancing interleaved coupled inductor high-gain converter in the sixth mode in one embodiment of this application.

[0033] Figure 9 This is a schematic diagram of the current flow in the seventh mode of a bipolar self-balancing interleaved coupled inductor high-gain converter in one embodiment of this application. Detailed Implementation

[0034] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0035] This application discloses a bipolar self-balancing interleaved-coupled inductor high-gain converter for DC microgrids. This bipolar self-balancing interleaved-coupled inductor high-gain converter combines an interleaved-coupled inductor structure with a voltage multiplier network and a switched capacitor network. (Please refer to...) Figure 1 The circuit diagram shown represents the bipolar self-balancing interleaved coupled inductor high-gain converter: DC input source V in The positive terminal is simultaneously connected to the primary winding of the first set of coupled inductors. L The same-name terminal of 1 and the primary winding of the second set of coupled inductors L The same terminal of 2, DC input source V in The negative terminal is grounded.

[0036] The primary winding of the first group of coupled inductors L 1. The non-same-name terminal is connected to the main switch transistor. S The drain of 1, the primary winding of the second set of coupled inductors L 2. The non-same-name terminal is connected to the main switch transistor. S 2's drain, main switch transistor S 1's source and main switch transistor S The sources of transistor 2 are commonly grounded. Main switch transistor. S 1 and main switch transistor S 2 respectively includes a body diode and a main switching transistor S The gate of transistor 1 is connected to the first drive signal, and the main switch transistor is... S The gate of 2 is connected to the second drive signal. The phase difference between the first drive signal and the second drive signal causes the main switch transistor to... S 1 and main switch transistor S 2. Interleaved work.

[0037] The first group of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L The non-identical terminals of the 4-pin coupling inductor are connected in series. The first group of coupled inductor secondary windings... L 3. Second group of coupled inductor secondary winding L The terminals of 4 are connected to a voltage multiplier network with an embedded switched capacitor network. This voltage multiplier network comprises multiple stages of voltage multiplier structures connected in series. The first stage of the voltage multiplier structure contains an embedded switched capacitor network and is connected between the primary and secondary windings of the two sets of coupled inductors. The last stage of the voltage multiplier structure is connected to the load. R .

[0038] The converter in this application employs a hybrid approach of voltage multiplier network and switched capacitor network on the output side to increase the output voltage. High-gain output and power expansion are achieved through the interleaved energy storage of two sets of coupled inductors and the voltage multiplication effect. By utilizing the turns ratio boosting characteristics of the interleaved coupled inductors and the voltage superposition effect of the multi-stage diode-capacitor voltage multiplier network, a high boost ratio can be obtained under conditions of low duty cycle and small coupled inductor turns ratio. This avoids the problems of increased leakage inductance, high core loss, and excessive device stress caused by traditional topologies that rely on extremely high duty cycles or ultra-large turns ratios. It significantly improves the boost capability over a wide input voltage range, making it suitable for scenarios where low-voltage new energy sources such as photovoltaics and energy storage supply power to high-voltage DC buses.

[0039] like Figure 1 As shown, the first-stage voltage multiplier structure with an embedded switched capacitor network includes diodes. D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 Auxiliary switching transistor S 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Each auxiliary diode contains a body diode.

[0040] diode D 1 Anode and diode D The cathodes of 2 are all connected to the primary winding of the first set of coupled inductors. L The non-identical terminal of 1, diode D 1 Cathode connected capacitor C The positive terminal of capacitor 1 is used to connect to the subsequent voltage multiplier structure. C 1. Negative terminal, capacitor C 21 Positive electrode, auxiliary switching transistor S The sources of 5 are all connected to the primary winding of the second set of coupled inductors. L The non-same-name terminals of 2 and the secondary winding of the first set of coupled inductors L The same terminal as 3. Capacitor. C 21 The negative terminals are respectively connected to the auxiliary switching transistors. S 3's drain and auxiliary switching transistor S 4 drain, auxiliary switching transistor S 4's source is connected to the auxiliary switch. S The drain of diode 5 and the positive terminal of capacitor C22. D The anodes of 2 are connected to capacitors respectively. C 22 negative electrode, auxiliary switching transistor S The source of 3 is used to connect to the subsequent voltage multiplier structure.

[0041] In this first-stage voltage multiplier structure with an embedded switched capacitor network, the diode D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 This forms the first stage of the voltage multiplier structure. Diode D 2. Capacitor C 21 ,capacitance C 22 Composition of main switching transistor S Clamping circuit of 1. Auxiliary switching transistor. S 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Capacitors C 21 ,capacitance C 22 Construct a switched capacitor network and use it as the main switch transistor S The clamping circuit of transistor 2. That is, the main switching transistor in this converter. S 1. A clamping circuit consisting of a single capacitor and a single diode is used, while the main switching transistor... S 2. A clamping circuit composed of a switched capacitor network, with two main switching transistors. S 1 and S The clamping circuits of 2 are no longer the same, which makes the operation of the converter no longer asymmetrical.

[0042] In addition to the first-stage voltage multiplier structure, the voltage multiplier network also includes a second-stage voltage multiplier structure and a third-stage voltage multiplier structure, such as... Figure 1 As shown, the second-stage voltage multiplier structure includes diodes. D 3. Diode D 4. Capacitor C 3. Capacitor C 4. The third-stage voltage multiplier structure includes diodes. D 5. Diode D 6. Output capacitor C 5. Output capacitor C 6.

[0043] In the second-stage voltage multiplier structure, the diode D The anode of 3 is connected to the diode in the first-stage voltage multiplier structure. D 1. Cathode, diode D 3 Cathode connected capacitor C The diode in the positive electrode and the third stage voltage multiplier structure of 3 D 5's anode. Capacitor. C 3. The negative terminal is connected to the capacitor. C 4's positive terminal and the second set of coupled inductor secondary windingsL The same terminal as 4. Capacitor. C The negative terminal of 4 is connected to the diode. D The diode in the anode and third-stage voltage multiplier structure of 4 D 6 cathode; diode D The cathode of the 4-stage diode is connected to the first-stage voltage multiplier structure. D 2 is the anode.

[0044] In the third-stage voltage multiplier structure, the diode D 5 Cathode connected to output capacitor C 5's positive electrode and load R The positive terminal. Output capacitor. C The negative terminal of 5 is connected to the output capacitor. C The positive terminals of 6 are grounded together, and the output capacitor... C The negative terminal of 6 is connected to the diode. D 6 Anode and load R The negative electrode.

[0045] The converter in this application uses two sets of coupled inductors, and the secondary windings of the two sets of coupled inductors are connected by two output capacitors. C 5 and output capacitor C 6. Sharing: While the parasitic parameters of the windings do not need to be kept consistent, the influence of these parameters is shared by the two output capacitors. This results in the parasitic parameters having the same effect on the output capacitors, which can cancel each other out, preventing output voltage imbalance and suppressing the influence of parasitic parameters from other components. Therefore, the two sets of coupled inductors used in this application can be wound directly using conventional methods, ensuring parameter consistency without special winding processes, thus reducing design and manufacturing complexity.

[0046] Figure 1 One switching cycle of the bipolar self-balancing interleaved coupled inductor high-gain converter shown includes t 0 o'clock to t Please refer to the time period of time 4. Figure 2 The first drive signal, the second drive signal, and the primary winding of the first set of coupled inductors are shown. L 1 current i L1 The second set of coupled inductor primary windings L 2 current i L2 The timing waveform diagram within one switching cycle: exist t 0 o'clock to t In a single moment, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the off state under the second drive signal.

[0047] exist t 1 hour to t Between 2 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second driving signal.

[0048] exist t 2 o'clock to t Between 3 moments, the main switch transistor S 1. Main switch transistor is in the off state under the first drive signal. S 2 is in the on state under the second driving signal.

[0049] exist t 3 o'clock to t Between 4 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second driving signal.

[0050] To eliminate the influence of parasitic parameters on bipolar voltage, the constraint of equal duty cycles in both phases needs to be eliminated. In this application, the duty cycle D1 of the first drive signal and the duty cycle D2 of the second drive signal can be equal or unequal. When the duty cycle D1 of the first drive signal and the duty cycle D2 of the second drive signal are unequal, the difference between duty cycles D1 and D2 is due to the output capacitance caused by the parasitic parameters of the coupling inductor. C 5 and output capacitor C The voltage difference between 6 is determined by feedback.

[0051] Furthermore, the phase difference between the first and second drive signals is related to the ripple magnitude. That is, an interleaved parallel structure is used on the input side to reduce input ripple, but the minimum point of the input current ripple is no longer when the phase shift is 180°. The first and second drive signals are... t 1 hour to t The phases that alternate between two time points are no longer fixed at 180°, but rather Phase shift angle The minimum current ripple is determined by the mutual compensation of the ripples of the two-phase input currents. The phase shift angle can be adjusted based on parasitic parameters and voltage detection results by detecting the magnitude of the input current ripple. The size is adjusted to achieve optimal input ripple.

[0052] Based on the above control logic, one switching cycle of this bipolar self-balancing interleaved coupled inductor high-gain converter includes seven modes performed sequentially, which are described below: (I) First mode: Main switch transistor S 1. Main switch transistor remains on under the first drive signal. S2 is turned off under the second drive signal. The data is stored in the primary winding of the second set of coupled inductors. L Energy in 2 is transferred to the capacitor. C 21 and capacitor C 22 Above, capacitor C 21 and capacitor C 22 Parallel charging; main switching transistor S The voltage stress of 2 is clamped by the capacitor parallel network. C 4. Discharge to capacitor C 21 and capacitor C 22 The capacitor parallel network and the output capacitor C 6. Charging. The first set of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L 4 via diode D 3. Freewheeling capacitor C 3. Charging, such as Figure 3 As shown.

[0053] When the main switch transistor S 2. When the circuit is just turned off, the primary winding of the second set of coupled inductors L The leakage current of 2 passes through the auxiliary switching transistor. S The body diode of transistor 4 is running, therefore the main switching transistor... S The voltage stress of 2 is twice that of the capacitance. C 21 It is the main switch transistor. S It has twice the voltage stress of 1, which is different from existing converters.

[0054] (II) Second mode: Main switch transistor S 1 is in the ON position under the first drive signal, and the main switch transistor is ON. S 2 is in the conducting state under the second driving signal. Since the inductor current cannot change suddenly, the diode... D If 6 is still conducting, then the capacitor will... C 4. Second group of coupled inductor secondary winding L 4. The first set of coupled inductor secondary windings L 3. Main switch transistor S 2. Output capacitor C 6. Diode D The circuit consisting of 6 elements still contains current, such as... Figure 4 As shown.

[0055] (III) Third mode: main switch transistor S 1. Turn off under the first drive signal, main switch transistor S2. The diode continues to be in the conducting state under the second driving signal. D 1. Diode D 6 is turned on, and part of the energy is stored in the primary winding of the first set of coupled inductors. L Energy in 1 is transferred to the capacitor. C 1 and through diode D 1. Main switch transistor S The voltage stress of 1 is clamped to the capacitor. C voltage of 1 V C1 With the main switch transistor S The voltage stresses of the two are not equal. The first set of coupled inductor secondary windings... L 3. Second group of coupled inductor secondary winding L 4 and capacitor C 4. Connected in series to provide output capacitor C 6. Charging, thereby increasing voltage gain, such as Figure 5 As shown.

[0056] (IV) Fourth mode: Main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The diode remains on under the second drive signal. D 4. Conducting, capacitor C 21 and capacitor C 22 Series discharge, to the capacitor C 4. Charging, with capacitor C The charging path for 3 is asymmetrical. DC input source. V in The first group of coupled inductor primary windings L 1. Capacitor C 1. Capacitor C 3. Series connection to the output capacitor C 5. Charging, such as Figure 6 As shown.

[0057] (V) Fifth mode, main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The first set of coupled inductor primary windings remains on under the second drive signal. L 1. Energy release complete, main switch transistor S 1. Achieving zero-current conduction to improve converter efficiency. Diode. D 1. When turned off, since the inductor current cannot change abruptly, the DC input source... V in The second set of coupled inductor primary windings L 2. The first set of coupled inductor secondary windings L 3. Second group of coupled inductor secondary windingL 4. Capacitor C 3. Diode D 5. Output capacitor C The circuit consisting of 5 components still has current flowing through it, supplying the output capacitor. C 5. Charging, such as Figure 7 As shown.

[0058] (VI) Sixth Mode: Main Switch S 1. Turns on under the first drive signal, main switch transistor S 2. Continues to be on under the second drive signal. DC input source V in For the primary winding of the first set of coupled inductors L 1. Second group of coupled inductor primary winding L 2. Energy storage, first set of coupled inductor secondary winding L 3. Second group of coupled inductor secondary winding L The current in diode 4 gradually decreases. When the current decreases to zero, the diode... D 4. Diode D 5. Zero-current turn-off, this mode ends, as shown below. Figure 8 As shown.

[0059] (VII) Seventh Mode: Main Switch Transistor S 1. Turns on under the first drive signal, main switch transistor S 2. Under the second drive signal, the diodes remain in the conducting state, and all diodes are in the reverse bias state, such as... Figure 9 As shown, during this period, the primary winding of the first set of coupled inductors L 1. Second group of coupled inductor primary winding L 2. From DC input source V in Linear charging.

[0060] As described above regarding the operation of each mode, the converter in this application effectively suppresses the voltage stress on the main switch, diodes, and capacitors through the voltage division effect of clamping circuits with different coupled inductor voltages and voltage multiplier networks, thus avoiding overvoltage problems in multi-stage voltage multiplier structures. Simultaneously, during converter operation, multiple diodes achieve zero-current turn-off (ZCS), and the main switch... S Both the diode and the 1 are in a soft-switching state, which significantly reduces switching losses and conduction losses, and improves the overall conversion efficiency.

[0061] By applying the volt-second balance principle of inductors during the switching cycle, we can obtain:

[0062] in, It is the main switching transistor SWhen 1 is turned on, the primary winding of the first set of coupled inductors L 1 voltage, It is the main switching transistor S 1. When turned off, the primary winding of the first set of coupled inductors L 1. Voltage. The main switching transistor during a switching cycle S 1. Conduction time, The main switching transistor during a switching cycle S 1. The time of shutdown.

[0063] From the above formula, the capacitance can be obtained. C voltage of 1 for:

[0064] Similarly, the capacitance can be obtained C 21 voltage and capacitors C 22 voltage for:

[0065] Based on the working process of the converter in each of the above modes, the capacitance can be obtained. C 3 voltage ,capacitance C 4 voltage Output capacitor C 5 voltage Output capacitor C 6 voltage The expression is:

[0066]

[0067]

[0068]

[0069] in, It is the main switching transistor S When 2 is turned on, the primary winding of the second set of coupled inductors L 2 voltage, It is the main switching transistor S When 1 is turned off, the primary winding of the second set of coupled inductors L 2. Voltage. It is the primary winding of the first set of coupled inductors L 1 and secondary winding L 3. Coupling turns ratio, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L The coupling coefficient is 3. It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L 4. Coupling turns ratio It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L The coupling coefficient is 4.

[0070] After rearranging the above formula, the output capacitance can be obtained. C 5 voltage Output capacitor C 6 voltage The expression is:

[0071]

[0072] Therefore even That is, the leakage inductance of the coupled inductors is different, and the duty cycle of the first drive signal is adjusted. D Duty cycle of 1 and the second drive signal D Two equal phases can also make the output capacitor C 5 voltage and output capacitor C 6 voltage Equal, which means that this bipolar self-balancing interleaved coupled inductor high-gain converter achieves voltage equalization and is consistent with the load. R Irrelevant.

[0073] because , Substitute voltage and voltage The voltage gain of this bipolar self-balancing interleaved coupled inductor high-gain converter can be obtained from the expression. M for:

[0074] When adjusting D 1= D 2= D At that time, voltage gain M for:

[0075] From voltage gain M The expression shows that the voltage gain of this bipolar self-balancing interleaved coupled inductor high-gain converter M Not only with duty cycle D 1 and D2. Related to, and also to, the turns ratio of the two sets of coupled inductors. N 1. N 2 and coupling coefficient K 1. K 2. Related. To obtain a larger voltage gain... M This can be achieved by adjusting the coupling coefficient. A higher output voltage is not required without a large duty cycle or a large turns ratio. The device voltage stress is not high and the conduction loss is low.

[0076] The above are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations that can be directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.

Claims

1. A bipolar self-balancing interleaved coupled inductor high-gain converter for DC microgrids, characterized in that, In the aforementioned bipolar self-balancing interleaved coupled inductor high-gain converter: DC input source V in The positive terminal is simultaneously connected to the primary winding of the first set of coupled inductors. L The same-name terminal of 1 and the primary winding of the second set of coupled inductors L The same terminal of 2, DC input source V in The negative terminal is grounded; The primary winding of the first group of coupled inductors L 1. The non-same-name terminal is connected to the main switch transistor. S The drain of 1, the primary winding of the second set of coupled inductors L 2. The non-same-name terminal is connected to the main switch transistor. S 2's drain, main switch transistor S 1's source and main switch transistor S The sources of transistor 2 are grounded together; the main switch transistor S The gate of transistor 1 is connected to the first drive signal, and the main switch transistor is... S The gate of 2 is connected to the second drive signal. The phase difference between the first drive signal and the second drive signal causes the main switch transistor to... S 1 and main switch transistor S 2. Interleaved work; The first group of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L The non-identical terminals of the 4-phase inductor are connected in series, and the first group of coupled inductor secondary windings... L 3. Second group of coupled inductor secondary winding L The terminals of 4 are respectively connected to a voltage multiplier network with an embedded switched capacitor network; the voltage multiplier network with the embedded switched capacitor network includes a multi-stage voltage multiplier structure connected in series, the first stage voltage multiplier structure has an embedded switched capacitor network, the first stage voltage multiplier structure with the embedded switched capacitor network is connected between the primary and secondary windings of the two sets of coupled inductors, and the last stage voltage multiplier structure is connected to the load. R .

2. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 1, characterized in that, The first-stage voltage multiplier structure, which incorporates a switched capacitor network, includes diodes. D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 Auxiliary switching transistor S 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Each auxiliary diode includes a body diode: diode D 1 Anode and diode D The cathodes of 2 are all connected to the primary winding of the first set of coupled inductors. L The non-identical terminal of 1, diode D 1 Cathode connected capacitor C The positive electrode of 1 and the structure used to connect to the subsequent voltage multiplier; capacitance C 1. Negative terminal, capacitor C 21 Positive electrode, auxiliary switching transistor S The sources of 5 are all connected to the primary winding of the second set of coupled inductors. L The non-same-name terminals of 2 and the secondary winding of the first set of coupled inductors L The same name end of 3; capacitance C 21 The negative terminals are respectively connected to the auxiliary switching transistors. S 3's drain and auxiliary switching transistor S 4 drain, auxiliary switching transistor S 4's source is connected to the auxiliary switch. S The drain of capacitor C5 and the positive terminal of capacitor C22; diode D The anodes of 2 are connected to capacitors respectively. C 22 negative electrode, auxiliary switching transistor S The source of 3 and the structure used to connect to the subsequent voltage multiplier; Among them, diode D 1. Diode D 2. Capacitor C 1. Capacitor C 21 ,capacitance C 22 This constitutes the first-stage voltage multiplier structure; diode D 2. Capacitor C 21 ,capacitance C 22 Composition of main switching transistor S Clamping circuit of 1; auxiliary switching transistor S 3. Auxiliary switching transistor S 4. Auxiliary switching transistor S 5. Capacitors C 21 ,capacitance C 22 Construct a switched capacitor network and use it as the main switch transistor S 2. Clamping circuit.

3. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 2, characterized in that, The voltage multiplier network further includes a second-stage voltage multiplier structure and a third-stage voltage multiplier structure; the second-stage voltage multiplier structure includes a diode. D 3. Diode D 4. Capacitor C 3. Capacitor C 4; The third-stage voltage multiplier structure includes diodes. D 5. Diode D 6. Output capacitor C 5. Output capacitor C 6; In the second-stage voltage multiplier structure, the diode D The anode of 3 is connected to the diode in the first-stage voltage multiplier structure. D 1. Cathode, diode D 3 Cathode connected capacitor C The diode in the positive electrode and the third stage voltage multiplier structure of 3 D 5's anode; capacitor C 3. The negative terminal is connected to the capacitor. C 4's positive terminal and the second set of coupled inductor secondary windings L 4's corresponding terminals; capacitor C The negative terminal of 4 is connected to the diode. D The diode in the anode and third-stage voltage multiplier structure of 4 D 6 cathode; diode D The cathode of the 4-stage diode is connected to the first-stage voltage multiplier structure. D 2's anode; In the third-stage voltage multiplier structure, the diode D 5 Cathode connected to output capacitor C 5's positive electrode and load R The positive terminal; the output capacitor C The negative terminal of 5 is connected to the output capacitor. C The positive terminals of 6 are grounded together, and the output capacitor... C The negative terminal of 6 is connected to the diode. D 6 Anode and load R The negative electrode.

4. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 3, characterized in that, Within one switching cycle of a bipolar self-balancing interleaved coupled inductor high-gain converter: exist t 0 o'clock to t In a single moment, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the off state under the second drive signal; exist t 1 hour to t Between 2 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second drive signal; exist t 2 o'clock to t Between 3 moments, the main switch transistor S 1. Main switch transistor is in the off state under the first drive signal. S 2 is in the on state under the second drive signal; exist t 3 o'clock to t Between 4 moments, the main switch transistor S 1. Main switch transistor is in the ON state under the first drive signal. S 2 is in the on state under the second drive signal; The duty cycle D1 of the first driving signal is equal to or unequal to the duty cycle D2 of the second driving signal, and the phase difference between the first driving signal and the second driving signal is related to the ripple magnitude.

5. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 4, characterized in that, The voltage gain of the bipolar self-balancing interleaved coupled inductor high-gain converter M for: in, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L 3. Coupling turns ratio, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L The coupling coefficient of 3; It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L 4. Coupling turns ratio It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L The coupling coefficient is 4. It is the duty cycle of the first drive signal. It is the duty cycle of the second drive signal.

6. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 4, characterized in that, Output capacitor C 5 voltage and output capacitor C 6 voltage The expression is: in, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L 3. Coupling turns ratio, It is the primary winding of the first set of coupled inductors L 1 and secondary winding L The coupling coefficient of 3; It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L 4. Coupling turns ratio It is the primary winding of the second set of coupled inductors. L 2 and secondary winding L The coupling coefficient is 4. It is the main switching transistor S When 1 is turned on, the primary winding of the first set of coupled inductors L 1 voltage, It is the main switching transistor S 1. When turned off, the primary winding of the first set of coupled inductors L 1 voltage and ; It is the main switching transistor S When 2 is turned on, the primary winding of the second set of coupled inductors L 2 voltage, It is the main switching transistor S When 1 is turned off, the primary winding of the second set of coupled inductors L 2 voltage; It is a capacitor C 1 voltage and ; It is a capacitor C 3 voltage and ; It is a capacitor C 4 voltage and ; It is a capacitor C 21 voltage, It is a capacitor C 22 The voltage, and ; When the duty cycle D1 of the first drive signal is equal to the duty cycle D2 of the second drive signal, the output capacitor... C 5 voltage and output capacitor C 6 voltage Equally, the bipolar self-balancing interleaved coupled inductor high-gain converter achieves voltage equalization.

7. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 4, characterized in that, One switching cycle of the bipolar self-balancing interleaved coupled inductor high-gain converter includes seven modes performed sequentially: First mode: Main switching transistor S 1. Main switch transistor remains on under the first drive signal. S 2 is turned off under the second drive signal and stored in the primary winding of the second set of coupled inductors. L Energy in 2 is transferred to the capacitor. C 21 and capacitor C 22 Above, capacitor C 21 and capacitor C 22 Parallel charging; main switching transistor S The voltage stress of 2 is clamped by the parallel network of capacitors; capacitors C 4. Discharge to capacitor C 21 and capacitor C 22 The capacitor parallel network and the output capacitor C 6. Charging; First group of coupled inductor secondary winding L 3. Second group of coupled inductor secondary winding L 4 via diode D 3. Freewheeling capacitor C 3. Charging; Second mode: Main switching transistor S 1 is in the ON position under the first drive signal, and the main switch transistor is ON. S 2 is in the conducting state under the second driving signal, diode D 6 remains conductive due to the capacitor. C 4. Second group of coupled inductor secondary winding L 4. The first set of coupled inductor secondary windings L 3. Main switch transistor S 2. Output capacitor C 6. Diode D The circuit consisting of 6 elements still contains current. Third mode: Main switching transistor S 1. Turn off under the first drive signal, main switch transistor S 2. The diode continues to be in the conducting state under the second driving signal. D 1. Diode D 6 is turned on, and part of the energy is stored in the primary winding of the first set of coupled inductors. L Energy in 1 is transferred to the capacitor. C 1 and through diode D 1. Main switch transistor S The voltage stress of 1 is clamped to the capacitor. C voltage of 1 V C1 With the main switch transistor S The voltage stresses of 2 are not equal; The first group of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L 4 and capacitor C 4. Connected in series to provide output capacitor C 6. Charging, thereby increasing voltage gain; Fourth mode: Main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The diode remains on under the second drive signal. D 4. Conducting, capacitor C 21 and capacitor C 22 Series discharge, to the capacitor C 4. Charging, with capacitor C The charging path of 3 is asymmetrical; DC input source V in The first group of coupled inductor primary windings L 1. Capacitor C 1. Capacitor C 3. Series connection to the output capacitor C 5. Charging; Fifth mode, main switch transistor S 1. Main switch transistor remains off under the first drive signal. S 2. The first set of coupled inductor primary windings remains on under the second drive signal. L 1. Energy release complete, main switch transistor S 1. Achieving zero-current conduction to improve converter efficiency; diodes D 1. Shutdown, from DC input source V in The second set of coupled inductor primary windings L 2. The first set of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L 4. Capacitor C 3. Diode D 5. Output capacitor C The circuit consisting of 5 components still has current flowing through it, supplying the output capacitor. C 5. Charging; Sixth mode: Main switch transistor S 1. Turns on under the first drive signal, main switch transistor S 2. Continues to be in the conducting state under the second drive signal; DC input source V in For the primary winding of the first set of coupled inductors L 1. Second group of coupled inductor primary winding L 2. Store energy; The first group of coupled inductor secondary windings L 3. Second group of coupled inductor secondary winding L The current in diode 4 gradually decreases. When the current decreases to zero, the diode... D 4. Diode D 5. Zero-current shutdown; Seventh mode: Main switch transistor S 1. Turns on under the first drive signal, main switch transistor S 2. Under the second drive signal, the diodes remain in the conducting state, and all diodes are in the reverse bias state. During this period, the primary winding of the first set of coupled inductors... L 1. Second group of coupled inductor primary winding L 2. From DC input source V in Linear charging.

8. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 6, characterized in that, When the bipolar self-balancing interleaved coupled inductor high-gain converter is in the first mode, when the main switch transistor... S 2. When the circuit is just turned off, the primary winding of the second set of coupled inductors L The leakage current of 2 passes through the auxiliary switching transistor. S The 4-pin body diode is running, and the main switching transistor is also running. S The voltage stress of 2 is twice that of the capacitance. C 21 It is the main switch transistor. S Twice the voltage stress of 1.

9. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 4, characterized in that, The first drive signal and the second drive signal are in t 1 hour to t The phases that alternate between two time points are: Phase shift angle The minimum current ripple is determined by the compensation of the ripples of the two-phase input currents.

10. The bipolar self-balancing interleaved coupled inductor high-gain converter according to claim 4, characterized in that, When the duty cycle D1 of the first drive signal is not equal to the duty cycle D2 of the second drive signal, the difference between the duty cycles D1 and D2 is caused by the output capacitance due to the parasitic parameters of the coupling inductor. C 5 and output capacitor C The voltage difference between 6 is determined by feedback.

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