A voltage spike absorption circuit for an energy storage inverter rectifier and its control method

Abstract

This invention discloses a voltage spike absorption circuit and its control method for an energy storage inverter rectifier, comprising: a PWM control circuit, a resonant transformer circuit, and a spike absorption circuit; the PWM control circuit is used to control the stability of the voltage output from the input terminal by turning the switching transistor on and off; the resonant transformer circuit is used to regulate the voltage during the voltage transfer from the input terminal to the load; the spike absorption circuit is used to suppress voltage spikes and oscillations generated when the voltage is input to the load. This circuit design is simple, uses fewer components, simplifies the circuit while improving mass production feasibility, has strong spike absorption capability, reduces product heat generation while shrinking the heat sink size, and increases power density by more than 5%.

Description

Technical Field

[0001] This invention relates to the field of energy storage power technology, and in particular to a voltage spike absorption circuit for an energy storage inverter rectifier and its control method. Background Technology

[0002] Currently, resonant boost PWM DC / DC converters for energy storage are widely used in energy storage products. They typically utilize the resonance between the resonant inductor, resonant capacitor, and the parasitic capacitance of the switching transistor to enable the boost switching MOSFET to turn on at zero voltage, achieving software switching. They feature low losses, a simplified structure, and flexible control, making them one of the excellent topologies for energy storage resonant boost DC / DC converters. However, due to the secondary-side rectifier diodes in traditional energy storage resonant boost ZVS PWM DC / DC converters, significant oscillations and voltage spikes occur during operation. This increases energy loss and heat generation, while also generating substantial EMI interference.

[0003] Therefore, there is an urgent need for a voltage spike absorption circuit for energy storage inverter rectifiers that can suppress voltage spikes and oscillations in the secondary rectifier diodes. Summary of the Invention

[0004] This invention provides a voltage spike absorption circuit and control method for an energy storage inverter rectifier, addressing the problems existing in current technologies. Currently, energy storage resonant boost PWM DC / DC converters are widely used in energy storage products. They typically utilize the resonance between the resonant inductor, resonant capacitor, and the parasitic capacitance of the switching transistor to enable the boost switching MOSFET to turn on at zero voltage, achieving software switching. This topology is characterized by low loss, simplified structure, and flexible control, making it one of the excellent topologies for energy storage resonant boost DC / DC converters. However, the secondary rectifier diodes of traditional energy storage resonant boost ZVS PWM DC / DC converters generate significant oscillations and voltage spikes during operation, increasing energy loss and heat generation, and causing substantial EMI interference.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A voltage spike absorption circuit for an energy storage inverter rectifier includes: a PWM control circuit, a resonant transformer circuit, and a spike absorption circuit;

[0007] The PWM control circuit is used to control the stability of the voltage output from the input terminal by turning the switching transistor on and off.

[0008] The resonant transformer circuit is used to regulate the voltage during the voltage transfer process from the input terminal to the load.

[0009] The spike absorption circuit is used to suppress voltage spikes and oscillations generated when voltage is input to the load.

[0010] The PWM control circuit includes: a first switch V1, a second switch V2, a third switch V3, and a fourth switch V4.

[0011] The first switch V1, the second switch V2, the third switch V3, and the fourth switch V4 are connected in sequence. By controlling the opening and closing of the first switch V1, the second switch V2, the third switch V3, and the fourth switch V4, the input line of the PWM signal is controlled to ensure voltage stability.

[0012] The resonant transformer circuit includes: an inductor circuit T1;

[0013] The inductor circuit T1 connects the PWM control circuit and the spike absorption circuit. When the voltage is transferred from the PWM control circuit to the spike absorption circuit, the voltage is boosted through the inductor circuit T1.

[0014] The peak absorption circuit includes: a first RCD peak absorption circuit, a second RCD peak absorption circuit, a third RCD peak absorption circuit, and a fourth RCD peak absorption circuit.

[0015] The first RCD peak absorption circuit, the second RCD peak absorption circuit, the third RCD peak absorption circuit, and the fourth RCD peak absorption circuit are connected in sequence by a circuit; by controlling the absorption and release of energy by the RCD, the peak voltage and oscillation generated in the circuit are suppressed.

[0016] The first RCD peak absorption circuit includes diode D2, resistor R1, capacitor C1, diode D4, and capacitor CD4; the second RCD peak absorption circuit includes diode D3, resistor R2, capacitor C2, diode D1, and capacitor CD1; the third RCD peak absorption circuit includes diode D7, resistor R3, capacitor C3, diode D6, and capacitor CD6; and the fourth RCD peak absorption circuit includes diode D8, resistor R4, capacitor C4, diode D5, and capacitor CD5.

[0017] In this circuit, diode D2, capacitor C1, and diode D4 are connected in sequence, resistor R1 is connected in parallel with capacitor C1, and capacitor CD4 is connected in parallel with diode D4, forming the first RCD spike absorption circuit.

[0018] One method for controlling a voltage spike absorption circuit in an energy storage inverter rectifier includes:

[0019] S101: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the first RCD spike absorption circuit and the fourth RCD spike absorption circuit are turned on.

[0020] S102: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the second RCD spike absorption circuit and the third RCD spike absorption circuit are turned on.

[0021] S103: When the resonant voltage is boosted, the spike energy generated by the spike absorption circuit is absorbed, and the spike voltage and oscillation generated by the circuit are suppressed.

[0022] Step S101 includes:

[0023] When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the control diodes D4 and D5 are turned on, and the capacitors CD1 and CD6 connected inside the diodes D1 and D6 are filled with charge, and energy is transferred from the input terminal to the load.

[0024] Diodes D1 and D6 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D1 charges capacitor C2 through diode D3, thus suppressing the reverse voltage spike. Resistor R2 releases the energy from capacitor C2 in each cycle.

[0025] Step S102 includes:

[0026] When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the control diodes D1 and D6 are turned on, and the capacitors CD4 and CD5 connected inside the diodes D4 and D5 are filled with charge, and energy is transferred from the input terminal to the load.

[0027] Diodes D4 and D5 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D4 charges capacitor C1 through diode D2, thus suppressing the reverse voltage spike. Resistor R1 releases the energy from capacitor C1 in each cycle.

[0028] Step S103 includes:

[0029] When the voltage is boosted through the resonant transformer circuit, resistors R1, R2, R3, and R4 generate voltage spikes and oscillations. Based on the spike absorption circuit, diode D in RCD conducts to charge capacitor C, and resistor R is responsible for releasing the energy accumulated in capacitor C in each cycle, absorbing spike energy, and suppressing the voltage spikes and oscillations generated by the circuit.

[0030] This includes:

[0031] When the voltage is boosted through the resonant transformer circuit, the over-temperature protection module is activated. When the temperature of the circuit exceeds 120°C, a high potential is output and the circuit stops working. When the temperature of the circuit is below 100°C, a low potential is output and the circuit resumes normal operation.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] A voltage spike absorption circuit for an energy storage inverter rectifier includes: a PWM control circuit, a resonant transformer circuit, and a spike absorption circuit. The PWM control circuit controls the stability of the voltage output from the input terminal by turning the switching transistor on and off. The resonant transformer circuit regulates the voltage during the voltage transfer from the input terminal to the load. The spike absorption circuit suppresses voltage spikes and oscillations generated when the voltage is input to the load. This circuit design is simple, uses fewer components, simplifies the circuit, improves mass production feasibility, has strong spike absorption capability, reduces product heat generation, reduces heat sink size, and increases power density by more than 5%.

[0034] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0035] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0036] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0037] Figure 1 This is a voltage spike absorption circuit diagram of an energy storage resonant boost rectifier diode in an embodiment of the present invention;

[0038] Figure 2 This is a diagram of the first RCD peak absorption circuit in an embodiment of the present invention;

[0039] Figure 3 This is a voltage spike absorption circuit diagram of an energy storage resonant boost rectifier diode in an embodiment of the present invention.

[0040] Figure 4 This is a flowchart of a voltage spike absorption circuit control method for an energy storage resonant boost rectifier diode in an embodiment of the present invention. Detailed Implementation

[0041] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0042] This invention provides a voltage spike absorption circuit for an energy storage inverter rectifier. Please refer to [link / reference]. Figures 1 to 4 This includes: PWM control circuit, resonant transformer circuit, and spike absorption circuit;

[0043] The PWM control circuit is used to control the stability of the voltage output from the input terminal by turning the switching transistor on and off.

[0044] The resonant transformer circuit is used to regulate the voltage during the voltage transfer process from the input terminal to the load.

[0045] The spike absorption circuit is used to suppress voltage spikes and oscillations generated when voltage is input to the load.

[0046] The working principle of the above technical solution is as follows: the PWM control circuit controls the stability of the voltage output from the input terminal by turning the switching transistor on and off; the resonant transformer circuit regulates the voltage during the voltage transfer from the input terminal to the load; and the spike absorption circuit suppresses voltage spikes and oscillations generated when the voltage is input to the load. This circuit design is simple, uses fewer components, simplifies the circuit while improving mass production feasibility, has strong spike absorption capability, reduces product heat generation, shrinks the heat sink size, and increases power density by more than 5%.

[0047] The beneficial effects of the above technical solution are as follows: the PWM control circuit is used to control the stability of the voltage output from the input terminal by turning the switching transistor on and off; the resonant transformer circuit is used to regulate the voltage during the voltage transfer from the input terminal to the load; and the spike absorption circuit is used to suppress voltage spikes and oscillations generated when the voltage is input to the load. This circuit design is simple, uses fewer components, simplifies the circuit while improving mass production feasibility, has strong spike absorption capability, reduces product heat generation, reduces heat sink size, and increases power density by more than 5%.

[0048] In another embodiment, the PWM control circuit includes: a first switch V1, a second switch V2, a third switch V3, and a fourth switch V4;

[0049] The first switch V1, the second switch V2, the third switch V3, and the fourth switch V4 are connected in sequence. By controlling the opening and closing of the first switch V1, the second switch V2, the third switch V3, and the fourth switch V4, the input line of the PWM signal is controlled to ensure voltage stability.

[0050] The working principle of the above technical solution is as follows: the first switch V1, the second switch V2, the third switch V3 and the fourth switch V4 are connected in sequence; by controlling the opening and closing of the first switch V1, the second switch V2, the third switch V3 and the fourth switch V4, the input line of the PWM signal is controlled to ensure the stability of the voltage.

[0051] The beneficial effects of the above technical solution are as follows: The first switch V1, the second switch V2, the third switch V3, and the fourth switch V4 are connected in sequence; by controlling the on and off states of the first switch V1, the second switch V2, the third switch V3, and the fourth switch V4, the input circuit of the PWM signal is controlled, ensuring voltage stability. This solves the EMI interference problem present in traditional energy storage inverter power supply circuits, while simultaneously improving the product's conversion efficiency, further reducing heat generation, and making the product more competitive in the market.

[0052] In another embodiment, the resonant transformer circuit includes: an inductor circuit T1;

[0053] The inductor circuit T1 connects the PWM control circuit and the spike absorption circuit. When the voltage is transferred from the PWM control circuit to the spike absorption circuit, the voltage is boosted through the inductor circuit T1.

[0054] The working principle of the above technical solution is as follows: the inductor circuit T1 is connected to the PWM control circuit and the spike absorption circuit. When the voltage is transferred from the PWM control circuit to the spike absorption circuit, the voltage is boosted through the inductor circuit T1.

[0055] The beneficial effects of the above technical solution are as follows: Inductor circuit T1 connects the PWM control circuit and the spike absorption circuit. During the voltage transfer from the PWM control circuit to the spike absorption circuit, the voltage is boosted through inductor circuit T1. This improves the product's conversion efficiency while further reducing the product's heat generation.

[0056] In another embodiment, the spike absorption circuit includes: a first RCD spike absorption circuit, a second RCD spike absorption circuit, a third RCD spike absorption circuit, and a fourth RCD spike absorption circuit.

[0057] The first RCD peak absorption circuit, the second RCD peak absorption circuit, the third RCD peak absorption circuit, and the fourth RCD peak absorption circuit are connected in sequence by a circuit; by controlling the absorption and release of energy by the RCD, the peak voltage and oscillation generated in the circuit are suppressed.

[0058] The working principle of the above technical solution is as follows: the first RCD peak absorption circuit, the second RCD peak absorption circuit, the third RCD peak absorption circuit, and the fourth RCD peak absorption circuit are connected sequentially through a circuit; by controlling the absorption and release of energy by the RCD, the peak voltage and oscillation generated in the circuit are suppressed. The addition of the RCD peak absorption circuit greatly helps to suppress voltage spikes and oscillations in the secondary-side rectifier diode, improving the product's conversion efficiency while further reducing the product's heat generation.

[0059] The beneficial effects of the above technical solution are as follows: the first RCD peak absorption circuit, the second RCD peak absorption circuit, the third RCD peak absorption circuit, and the fourth RCD peak absorption circuit are connected sequentially through circuitry; by controlling the absorption and release of energy by the RCD, the peak voltage and oscillation generated in the circuit are suppressed. The addition of the RCD peak absorption circuit significantly reduces voltage spikes and oscillations in the secondary-side rectifier diode, improving product conversion efficiency while further reducing product heat generation.

[0060] In another embodiment, the first RCD peak absorption circuit includes diode D2, resistor R1, capacitor C1, diode D4, and capacitor CD4; the second RCD peak absorption circuit includes diode D3, resistor R2, capacitor C2, diode D1, and capacitor CD1; the third RCD peak absorption circuit includes diode D7, resistor R3, capacitor C3, diode D6, and capacitor CD6; and the fourth RCD peak absorption circuit includes diode D8, resistor R4, capacitor C4, diode D5, and capacitor CD5.

[0061] In this circuit, diode D2, capacitor C1, and diode D4 are connected in sequence, resistor R1 is connected in parallel with capacitor C1, and capacitor CD4 is connected in parallel with diode D4, forming the first RCD peak absorption circuit.

[0062] Diode D3, capacitor C2, and diode D1 are connected in sequence. Resistor R2 is connected in parallel with capacitor C2, and capacitor CD1 is connected in parallel with diode D1, forming the second RCD peak absorption circuit.

[0063] Diode D7, capacitor C3, and diode D6 are connected in sequence. Resistor R3 is connected in parallel with capacitor C3, and capacitor CD6 is connected in parallel with diode D6, forming the third RCD peak absorption circuit.

[0064] Diode D8, capacitor C4, and diode D5 are connected in sequence. Resistor R4 is connected in parallel with capacitor C4, and capacitor CD5 is connected in parallel with diode D5, forming the fourth RCD peak absorption circuit.

[0065] The working principle of the above technical solution is as follows: Diode D2, capacitor C1, and diode D4 are connected in sequence, resistor R1 is connected in parallel with capacitor C1, and capacitor CD4 is connected in parallel with diode D4, forming the first RCD peak absorption circuit; Diode D3, capacitor C2, and diode D1 are connected in sequence, resistor R2 is connected in parallel with capacitor C2, and capacitor CD1 is connected in parallel with diode D1, forming the second RCD peak absorption circuit; Diode D7, capacitor C3, and diode D6 are connected in sequence, resistor R3 is connected in parallel with capacitor C3, and capacitor CD6 is connected in parallel with diode D6, forming the third RCD peak absorption circuit; Diode D8, capacitor C4, and diode D5 are connected in sequence, resistor R4 is connected in parallel with capacitor C4, and capacitor CD5 is connected in parallel with diode D5, forming the fourth RCD peak absorption circuit. The addition of the RCD peak absorption circuit greatly helps suppress voltage spikes and oscillations in the secondary rectifier diodes, improving product conversion efficiency while further reducing heat generation.

[0066] The beneficial effects of the above technical solution are as follows: Diode D2, capacitor C1, and diode D4 are connected in sequence, resistor R1 is connected in parallel with capacitor C1, and capacitor CD4 is connected in parallel with diode D4, forming the first RCD peak absorption circuit; Diode D3, capacitor C2, and diode D1 are connected in sequence, resistor R2 is connected in parallel with capacitor C2, and capacitor CD1 is connected in parallel with diode D1, forming the second RCD peak absorption circuit; Diode D7, capacitor C3, and diode D6 are connected in sequence, resistor R3 is connected in parallel with capacitor C3, and capacitor CD6 is connected in parallel with diode D6, forming the third RCD peak absorption circuit; Diode D8, capacitor C4, and diode D5 are connected in sequence, resistor R4 is connected in parallel with capacitor C4, and capacitor CD5 is connected in parallel with diode D5, forming the fourth RCD peak absorption circuit. The addition of the RCD peak absorption circuit significantly reduces voltage spikes and oscillations in the secondary-side rectifier diodes, improving product conversion efficiency while further reducing heat generation.

[0067] In another embodiment, a method for controlling a voltage spike absorption circuit in an energy storage inverter rectifier includes:

[0068] S101: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the first RCD spike absorption circuit and the fourth RCD spike absorption circuit are turned on.

[0069] S102: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the second RCD spike absorption circuit and the third RCD spike absorption circuit are turned on.

[0070] S103: When the resonant voltage is boosted, the spike energy generated by the spike absorption circuit is absorbed, and the spike voltage and oscillation generated by the circuit are suppressed.

[0071] The working principle of the above technical solution is as follows: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the first RCD peak absorption circuit and the fourth RCD peak absorption circuit are turned on; when the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the second RCD peak absorption circuit and the third RCD peak absorption circuit are turned on; during resonant boost, the peak energy generated by the peak absorption circuit is absorbed, suppressing the peak voltage and oscillation generated by the circuit. This solves the EMI interference problem of traditional energy storage inverter power supply circuits, while improving the conversion efficiency of the product, further reducing heat generation, and making the product more competitive in the market.

[0072] The beneficial effects of the above technical solution are as follows: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the first RCD peak absorption circuit and the fourth RCD peak absorption circuit are controlled to turn on; when the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the second RCD peak absorption circuit and the third RCD peak absorption circuit are controlled to turn on; during resonant boost, based on the peak absorption circuit, the peak energy generated by the absorption circuit is absorbed, suppressing the peak voltage and oscillation generated by the circuit. This solves the EMI interference problem of traditional energy storage inverter power supply circuits, while improving the conversion efficiency of the product, further reducing heat generation, and making the product more competitive in the market.

[0073] In another embodiment, step S101 includes:

[0074] When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the control diodes D4 and D5 are turned on, and the capacitors CD1 and CD6 connected inside the diodes D1 and D6 are filled with charge, and energy is transferred from the input terminal to the load.

[0075] Diodes D1 and D6 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D1 charges capacitor C2 through diode D3, thus suppressing the reverse voltage spike. Resistor R2 releases the energy from capacitor C2 in each cycle.

[0076] The working principle of the above technical solution is as follows: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the control diodes D4 and D5 are turned on. The capacitors CD1 and CD6 connected inside the diodes D1 and D6 are filled with charge, and energy is transferred from the input terminal to the load. The diodes D1 and D6 reverse the energy transferred in the load and turn off, generating a large reverse voltage spike. The voltage spike across the diode D1 charges the capacitor C2 through the diode D3. By charging the capacitor C2, the reverse voltage spike is suppressed. The resistor R2 releases the energy of the capacitor C2 in each cycle.

[0077] The beneficial effects of the above technical solution are as follows: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the control diodes D4 and D5 are turned on. The capacitors CD1 and CD6 connected inside diodes D1 and D6 are fully charged, and energy is transferred from the input terminal to the load. Diodes D1 and D6 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D1 charges capacitor C2 through diode D3, thus suppressing the reverse voltage spike. Resistor R2 releases the energy of capacitor C2 in each cycle. The RCD absorption circuit design is simple, uses fewer components, and improves mass production while simplifying the circuit. EMI interference is significantly reduced, and the product power density is higher. While reducing the product heat generation, the heat sink size is also reduced, increasing the power density by more than 5%.

[0078] In another embodiment, step S102 includes:

[0079] When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the control diodes D1 and D6 are turned on, and the capacitors CD4 and CD5 connected inside the diodes D4 and D5 are filled with charge, and energy is transferred from the input terminal to the load.

[0080] Diodes D4 and D5 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D4 charges capacitor C1 through diode D2, thus suppressing the reverse voltage spike. Resistor R1 releases the energy from capacitor C1 in each cycle.

[0081] The working principle of the above technical solution is as follows: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the control diodes D1 and D6 are turned on. The capacitors CD4 and CD5 connected inside the diodes D4 and D5 are filled with charge, and energy is transferred from the input terminal to the load. The diodes D4 and D5 reverse cut off the energy transferred in the load, and a large reverse voltage spike is generated when they are turned off. The voltage spike across the diode D4 charges the capacitor C1 through the diode D2. By charging the capacitor C1, the reverse voltage spike is suppressed. The resistor R1 releases the energy of the capacitor C1 in each cycle.

[0082] During the conduction of the second switch V2 and the fourth switch V4, the voltage does not immediately drop to zero, but has a rise time. At the same time, the current does not immediately rise to the load current, but also has a rise time. During this period, the voltage and current overlap, resulting in conduction losses. When the first switch V1 and the third switch V3 are turned off, the voltage of the first switch V1 and the third switch V3 does not immediately rise to the power supply voltage, but has a rise time. At the same time, the current of the switches does not immediately drop to zero, but also has a fall time. During this period, the voltage and current also overlap, resulting in turn-off losses. The resulting turn-on losses and turn-off losses are collectively referred to as switching losses.

[0083] Under certain conditions, the switching loss of the switching transistor in each cycle is constant, and the formula for the switching loss of its PWM control circuit is:

[0084]

[0085] in, This indicates the switching losses of the PWM control circuit. , , , These represent the switching frequencies of the second switch V2, the fourth switch V4, the first switch V1, and the third switch V3, respectively. This indicates the maximum value of conduction overlap. This indicates the maximum value of the off-interval overlap. , , , This is expressed as the voltage value corresponding to the switching transistor. , , , This indicates the current value corresponding to the switching transistor.

[0086] By acquiring the switching losses of the PWM control circuit, the circuit can be adjusted according to the current switching loss, which can greatly reduce or even eliminate losses and switching noise.

[0087] The beneficial effects of the above technical solution are as follows: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the control diodes D1 and D6 are turned on. The capacitors CD4 and CD5 connected inside diodes D4 and D5 are fully charged, and energy is transferred from the input terminal to the load. Diodes D4 and D5 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike during turn-off. The voltage spike across diode D4 charges capacitor C1 through diode D2, suppressing the reverse voltage spike by charging capacitor C1. Resistor R1 releases the energy of capacitor C1 in each cycle. This ensures that the current in the diodes drops to zero before the disconnect signal arrives during operation, ensuring that the switching devices disconnect under zero current conditions, thereby greatly reducing the disconnection loss of the switching devices and also greatly reducing the voltage spikes that may occur when disconnecting inductive loads.

[0088] In another embodiment, step S103 includes:

[0089] When the voltage is boosted through the resonant transformer circuit, resistors R1, R2, R3, and R4 generate voltage spikes and oscillations. Based on the spike absorption circuit, diode D in RCD conducts to charge capacitor C, and resistor R is responsible for releasing the energy accumulated in capacitor C in each cycle, absorbing spike energy, and suppressing the voltage spikes and oscillations generated by the circuit.

[0090] The working principle of the above technical solution is as follows: When the voltage is boosted through the resonant transformer circuit, resistors R1, R2, R3, and R4 generate peak voltages and oscillations. Based on the peak absorption circuit, diode D in RCD conducts to charge capacitor C, and resistor R is responsible for releasing the energy accumulated by capacitor C in each cycle, absorbing peak energy, and suppressing the peak voltages and oscillations generated by the circuit.

[0091] Minor differences in device parameters and variations in operating device temperature cause conduction losses in various circuits, including those of switching devices and diodes, switching losses of switching devices, reverse recovery losses of freewheeling diodes, absorption circuit losses, and the inherent losses of DC capacitors. These losses can lead to deviations in capacitor voltage within the circuit. Therefore, it is necessary to perform balanced control of the capacitors and voltages in the circuit to ensure that both vary within a reasonable range.

[0092] The capacitor voltages in the circuit are sorted, and then the current is used to determine whether the capacitors are charging or discharging. If they are discharging, the circuits with higher capacitor voltages are switched on first; if they are charging, the circuits with lower capacitor voltages are switched on first. A multi-level modulation strategy is used to determine the number of circuits to be switched on, and the final switching trigger pulse is generated based on the priority and number of switched circuits. Under this circuit switching selection mechanism, during discharge, the capacitors in circuits with higher voltages participate in discharging for a longer time, resulting in a greater decrease in capacitor voltage; during charging, the capacitors in circuits with lower voltages participate in charging for a longer time, resulting in a greater increase in capacitor voltage. This process repeats until the capacitor voltages in the circuit are eventually balanced.

[0093] The beneficial effects of the above technical solution are as follows: When the voltage is boosted through the resonant transformer circuit, resistors R1, R2, R3, and R4 generate voltage spikes and oscillations. Based on the spike absorption circuit, diode D in the RCD conducts to charge capacitor C, and resistor R is responsible for releasing the energy accumulated in capacitor C in each cycle, absorbing the spike energy, and suppressing the voltage spikes and oscillations generated by the circuit. The RCD absorption circuit design is simple, uses fewer components, and improves mass production while simplifying the circuit. EMI interference is significantly reduced, the product power density is higher, and the heatsink size is reduced while lowering the product heatsink size, thus increasing the power density by more than 5%.

[0094] In another embodiment, when the voltage is boosted through the resonant transformer circuit, the over-temperature protection module is activated. When the temperature of the circuit exceeds 120°C, a high potential is output and the circuit stops working. When the temperature of the circuit is below 100°C, a low potential is output and the circuit resumes normal operation.

[0095] The working principle of the above technical solution is as follows: When the circuit temperature is below 100℃ (not overheated), the output is low, and T1 is cut off; when the circuit temperature exceeds 120℃ (overheated), the output is high, and T1 is turned on. When the circuit temperature is above 120℃, the potential at the positive input terminal of the circuit is greater than the potential at the negative input terminal, and the output is high. When the circuit fault is cleared or the heat is released, for stability considerations, the output is high when the circuit temperature is below 100℃, so that the circuit can operate normally.

[0096] The beneficial effects of the above technical solution are as follows: When the voltage is boosted through the resonant transformer circuit, the over-temperature protection module is activated. When the circuit temperature exceeds 120℃, a high potential is output and the circuit stops working. When the circuit temperature is below 100℃, a low potential is output and the circuit resumes normal operation. This avoids circuit losses caused by excessively high temperatures during circuit operation.

[0097] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A voltage spike absorption circuit for an energy storage inverter rectifier, characterized in that, include: PWM control circuit, resonant transformer circuit, and spike absorption circuit; The PWM control circuit is used to control the stability of the voltage output from the input terminal by turning the switching transistors on and off; it includes: a first switching transistor V1, a second switching transistor V2, a third switching transistor V3, and a fourth switching transistor V4; the first switching transistor V1, the second switching transistor V2, the third switching transistor V3, and the fourth switching transistor V4 are connected in sequence; by controlling the turning on and off of the first switching transistor V1, the second switching transistor V2, the third switching transistor V3, and the fourth switching transistor V4, the input line of the PWM signal is controlled to ensure voltage stability; The resonant transformer circuit is used to regulate the voltage during the voltage transfer from the input terminal to the load; it includes: an inductor circuit T1; the inductor circuit T1 is connected to the PWM control circuit and the spike absorption circuit, and the voltage is boosted through the inductor circuit T1 during the voltage transfer from the PWM control circuit to the spike absorption circuit. The spike absorption circuit is used to suppress the generated spike voltage and oscillation when the voltage is input to the load; it includes: a first RCD spike absorption circuit, a second RCD spike absorption circuit, a third RCD spike absorption circuit, and a fourth RCD spike absorption circuit. The first RCD peak absorption circuit, the second RCD peak absorption circuit, the third RCD peak absorption circuit, and the fourth RCD peak absorption circuit are connected in sequence by a circuit; by controlling the absorption and release of energy by the RCD, the peak voltage and oscillation generated in the circuit are suppressed; RCD refers to resistor-capacitor-diode. The first RCD peak absorption circuit includes diode D2, resistor R1, capacitor C1, diode D4, and capacitor CD4; the second RCD peak absorption circuit includes diode D3, resistor R2, capacitor C2, diode D1, and capacitor CD1; the third RCD peak absorption circuit includes diode D7, resistor R3, capacitor C3, diode D6, and capacitor CD6; the fourth RCD peak absorption circuit includes diode D8, resistor R4, capacitor C4, diode D5, and capacitor CD5. In this circuit, diode D2, capacitor C1, and diode D4 are connected in sequence, resistor R1 is connected in parallel with capacitor C1, and capacitor CD4 is connected in parallel with diode D4, forming the first RCD spike absorption circuit.

2. A method for controlling voltage spike absorption circuits in an energy storage inverter rectifier, characterized in that, The voltage spike absorption circuit of the energy storage inverter rectifier as described in claim 1 includes: S101: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the first RCD spike absorption circuit and the fourth RCD spike absorption circuit are turned on. S102: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the second RCD spike absorption circuit and the third RCD spike absorption circuit are turned on. S103: When the resonant voltage is boosted, the spike energy generated by the spike absorption circuit is absorbed, and the spike voltage and oscillation generated by the circuit are suppressed.

3. The method for controlling voltage spike absorption circuit of an energy storage inverter rectifier according to claim 2, characterized in that, Step S101 includes: When the first switch V1 and the third switch V3 are turned on, and the second switch V2 and the fourth switch V4 are turned off, the control diodes D4 and D5 are turned on, and the capacitors CD1 and CD6 connected inside the diodes D1 and D6 are filled with charge, and energy is transferred from the input terminal to the load. Diodes D1 and D6 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D1 charges capacitor C2 through diode D3, thus suppressing the reverse voltage spike. Resistor R2 releases the energy from capacitor C2 in each cycle.

4. The method for controlling voltage spike absorption circuit of an energy storage inverter rectifier according to claim 2, characterized in that, Step S102 includes: When the second switch V2 and the fourth switch V4 are turned on, and the first switch V1 and the third switch V3 are turned off, the control diodes D1 and D6 are turned on, and the capacitors CD4 and CD5 connected inside the diodes D4 and D5 are filled with charge, and energy is transferred from the input terminal to the load. Diodes D4 and D5 reverse-cut off the energy transferred in the load, generating a large reverse voltage spike when turned off. The voltage spike across diode D4 charges capacitor C1 through diode D2, thus suppressing the reverse voltage spike. Resistor R1 releases the energy from capacitor C1 in each cycle.

5. The method for controlling voltage spike absorption circuit of an energy storage inverter rectifier according to claim 2, characterized in that, Step S103 includes: When the voltage is boosted through the resonant transformer circuit, resistors R1, R2, R3, and R4 generate voltage spikes and oscillations. Based on the conduction of the diodes in the corresponding RCD peak absorption circuit, the corresponding capacitors are charged. The resistors are responsible for releasing the energy accumulated by the corresponding capacitors in each cycle, absorbing the peak energy, and suppressing the voltage spikes and oscillations generated by the circuit.

6. The method for controlling voltage spike absorption circuit of an energy storage inverter rectifier according to claim 5, characterized in that, include: When the voltage is boosted through the resonant transformer circuit, the over-temperature protection module is activated. When the temperature of the circuit exceeds 120°C, a high potential is output and the circuit stops working. When the temperature of the circuit is below 100°C, a low potential is output and the circuit resumes normal operation.

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