Staggered anti-laser photovoltaic inverter and design method

Abstract

The invention discloses an interlaced anti-laser photovoltaic inverter and a design method, and relates to the technical field of inverter design. In the first aspect, by tracking the maximum power point of the power supply, it is ensured that the power supply works in the optimal working state, the situation that the working performance of the interlaced anti-laser photovoltaic inverter is low due to the fact that the interlaced anti-laser photovoltaic inverter is affected by temperature and illumination intensity is avoided, and voltage and current are converted again through the inversion module; the solar energy conversion performance and the power grid output efficiency of the interlaced anti-laser photovoltaic inverter are improved, and the working performance of the interlaced anti-laser photovoltaic inverter is improved. And on the other hand, the optimal interlaced anti-laser photovoltaic inverter is determined through the optimal winding mode and the optimal air gap division number in combination with a preset air gap avoidance method. By designing the winding method of the flyback transformer, dividing the air gap and avoiding the air gap, the winding loss of the flyback transformer is reduced, and the working performance of the staggered anti-laser photovoltaic inverter is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of inverter design, and in particular relates to an interleaved inverter and a design method thereof. Background Art

[0002] With the increasing demand for electricity by residents, the power system is constantly developing and growing, and more and more new energy sources are being used in the power system. Photovoltaic power generation system is a power generation system that uses the photovoltaic effect of photovoltaic cells to directly convert solar radiation energy into electrical energy. Photovoltaic power generation system mainly includes solar cells (i.e. power source), photovoltaic inverter and power grid. In photovoltaic power generation system, photovoltaic inverter is a device that converts direct current (DC) power into alternating current (AC) power, and is the core component of photovoltaic power generation system.

[0003] However, in the current photovoltaic power generation system, photovoltaic inverters usually convert solar energy based on a fixed working power. However, due to the variability and instability of solar energy, for example, the daily solar sunshine intensity and sunshine duration are constantly fluctuating, and photovoltaic inverters working with a fixed working power are obviously unable to adapt to the characteristics of solar energy, resulting in poor working performance of photovoltaic inverters. In addition, the winding loss of existing photovoltaic inverters is gradually increasing with the passage of working time, which also leads to low working performance of photovoltaic inverters. Therefore, there is an urgent need for an interleaved photovoltaic inverter and a design method to solve the defects of the prior art. Summary of the invention

[0004] The present invention aims to provide an interleaved flyback volt-volt inverter and a design method to solve the above technical problems, and to perform flyback transformation on the current and voltage output by the power supply through the maximum power point of the power supply, thereby improving the working performance of the interleaved flyback volt-volt inverter.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides an interleaved anti-light volt-to-volt inverter, which is applicable to power supplies and power grids, including:

[0006] Flyback transformer module, inverter module and filter module;

[0007] The input end of the flyback transformer module is electrically connected to the output end of the power supply;

[0008] The output end of the flyback transformer module is electrically connected to the input end of the inverter module;

[0009] The output end of the inverter module is electrically connected to the input end of the filter module;

[0010] The output end of the filter module is electrically connected to the power grid;

[0011] The flyback transformer module is used to convert the DC voltage and DC current output by the power supply into a half-sine wave voltage and a half-sine wave current according to the maximum power point of the power supply;

[0012] The inverter module is used to convert the half-sine wave voltage and half-sine wave current output by the flyback transformer module into an alternating current voltage and an alternating current according to the current phase and the voltage phase of the power grid;

[0013] The filtering module is used to filter the AC voltage and AC current output by the inverter module and then output them to the power grid.

[0014] It can be understood that, compared with the prior art, the present invention converts the DC voltage and DC current output by the power supply into a half-sine wave voltage and a half-sine wave current according to the maximum power point of the power supply through the flyback transformer module, and the inverter module converts the half-sine wave voltage and the half-sine wave current output by the flyback transformer module into an AC voltage and an AC current according to the current phase and the voltage phase of the power grid. The AC voltage and the AC current output by the inverter module are filtered by the filter module and then output to the power grid, thereby realizing the conversion of the DC voltage and current of the power supply into a voltage and current matching the power grid. The present invention ensures that the power supply works in the best working state by tracking the maximum power point of the power supply, so that the flyback transformer module can obtain the maximum output electric energy, avoids the low working performance of the interlaced flyback volt-volt inverter due to the influence of temperature and light intensity, and converts the voltage and current again through the inverter module, thereby improving the conversion performance of the interlaced flyback volt-volt inverter for solar energy and the output efficiency to the power grid, and improving the working performance of the interlaced flyback volt-volt inverter.

[0015] As a preferred solution, the flyback transformer module includes: a first flyback transformer unit and a second flyback transformer unit;

[0016] The first flyback transformer unit and the second flyback transformer unit are both used to convert the DC voltage output by the power supply into a half-sine wave voltage and a half-sine wave current;

[0017] The phase difference between the half-sine wave voltage and the half-sine wave current output by the first flyback transformer unit and the half-sine wave voltage and the half-sine wave current output by the second flyback transformer unit is 180 degrees.

[0018] As a preferred solution, the first flyback transformer unit includes: a first flyback transformer, a first rectifier diode, a first capacitor, a first slave main switch tube, a first auxiliary switch tube, a first active clamp capacitor and a first auxiliary capacitor;

[0019] A first end of the first active clamping capacitor is electrically connected to a first end of the power supply;

[0020] The second end of the first active clamping capacitor is electrically connected to the first end of the first auxiliary switch tube;

[0021] The second end of the first auxiliary switch tube is electrically connected to the second end of the primary inductor of the first flyback transformer;

[0022] A first end of the primary inductor of the first flyback transformer is electrically connected to a first end of the power supply;

[0023] The first end of the first slave main switch is electrically connected to the second end of the primary inductor of the first flyback transformer;

[0024] The second end of the first slave main switch is electrically connected to the second end of the power supply;

[0025] The first end of the first auxiliary capacitor is electrically connected to the first end of the first slave main switch tube;

[0026] The second end of the first auxiliary capacitor is electrically connected to the second end of the first slave main switch tube;

[0027] A first end of the secondary inductor of the first flyback transformer is electrically connected to a first end of the first rectifier diode;

[0028] The first end of the first capacitor is electrically connected to the second end of the first rectifier diode;

[0029] The second end of the first capacitor is electrically connected to the second end of the secondary inductor of the first flyback transformer;

[0030] The second end of the secondary inductor of the first flyback transformer is electrically connected to the input end of the inverter module;

[0031] The second end of the first rectifier diode is electrically connected to the input end of the inverter module.

[0032] As a preferred solution, the second flyback transformer unit includes: a second flyback transformer, a second rectifier diode, a second capacitor, a second slave main switch tube, a second auxiliary switch tube, a second active clamping capacitor and a second auxiliary capacitor;

[0033] A first end of the second active clamping capacitor is electrically connected to a first end of the power supply;

[0034] The second end of the second active clamping capacitor is electrically connected to the first end of the second auxiliary switch tube;

[0035] The second end of the second auxiliary switch tube is electrically connected to the second end of the primary inductor of the second flyback transformer;

[0036] A first end of the primary inductor of the second flyback transformer is electrically connected to a first end of the power supply;

[0037] The first end of the second slave main switch is electrically connected to the second end of the primary inductor of the second flyback transformer;

[0038] The second end of the second slave main switch is electrically connected to the second end of the power supply;

[0039] The first end of the second auxiliary capacitor is electrically connected to the first end of the second slave main switch tube;

[0040] The second end of the second auxiliary capacitor is electrically connected to the second end of the second slave main switch tube;

[0041] A first end of the secondary inductor of the second flyback transformer is electrically connected to a first end of the second rectifier diode;

[0042] The first end of the second capacitor is electrically connected to the second end of the second rectifier diode;

[0043] The second end of the second capacitor is electrically connected to the second end of the secondary inductor of the second flyback transformer;

[0044] The second end of the secondary inductor of the second flyback transformer is electrically connected to the input end of the inverter module;

[0045] The second end of the second rectifier diode is electrically connected to the input end of the inverter module.

[0046] As a preferred embodiment, the winding method of the first flyback transformer and the second flyback transformer is alternating winding; the air gap of the first flyback transformer and the second flyback transformer is composed of a plurality of identical sub-air gaps; the windings and air gaps of the first flyback transformer and the second flyback transformer are not in contact with each other.

[0047] As a preferred solution, the inverter module includes: a first switch tube, a second switch tube, a third switch tube and a fourth switch tube;

[0048] The first end of the first switch tube is electrically connected to the second end of the first rectifier diode;

[0049] The first end of the first switch tube is electrically connected to the second end of the second rectifier diode;

[0050] The first end of the second switch tube is electrically connected to the second end of the secondary inductor of the first flyback transformer;

[0051] The first end of the second switch tube is electrically connected to the second end of the secondary inductor of the second flyback transformer;

[0052] The first end of the third switch tube is electrically connected to the first end of the second switch tube;

[0053] The first end of the fourth switch tube is electrically connected to the first end of the first switch tube;

[0054] The second end of the first switch tube is electrically connected to the input end of the filter module;

[0055] The second end of the second switch tube is electrically connected to the input end of the filter module;

[0056] The second end of the third switch tube is electrically connected to the input end of the filter module;

[0057] The second end of the fourth switch tube is electrically connected to the input end of the filter module.

[0058] As a preferred solution, the filtering module includes: a filtering capacitor and a filtering inductor;

[0059] The first end of the filter inductor is electrically connected to the second end of the first switch tube, the second end of the second switch tube, the second end of the third switch tube and the second end of the fourth switch tube respectively;

[0060] The second end of the filter inductor is electrically connected to the power grid;

[0061] The first end of the filter capacitor is electrically connected to the first end of the filter inductor;

[0062] The second end of the filter capacitor is electrically connected to the second end of the first switch tube;

[0063] The second end of the filter capacitor is electrically connected to the second end of the second switch tube;

[0064] The second end of the filter capacitor is electrically connected to the power grid.

[0065] As a preferred solution, the interleaved anti-laser volt-to-volt inverter further includes: a detection module, a processor module and a drive module;

[0066] The input end of the detection module is electrically connected to the flyback transformer module, the inverter module, the power supply and the power grid;

[0067] The output end of the detection module is electrically connected to the input end of the processor module;

[0068] The output end of the processor module is electrically connected to the input end of the driving module;

[0069] The output end of the driving module is electrically connected to the flyback transformer module and the inverter module;

[0070] The detection module is used to detect the current and voltage information of the power supply and the power grid;

[0071] The processor module is used to obtain the maximum power point of the power supply according to the current and voltage information of the power supply, output the transformer drive instruction of the flyback transformer module, and obtain the current phase and grid phase of the grid according to the current and voltage information of the grid, and output the inverter drive instruction of the inverter module;

[0072] The driving module is used to complete the regulation of the flyback transformer module according to the transformer driving instruction, and to complete the regulation of the inverter module according to the inverter driving instruction.

[0073] Accordingly, an embodiment of the present invention provides a design method of an interleaved anti-light volt-to-volt inverter, which is applicable to the interleaved anti-light volt-to-volt inverter as described above, comprising:

[0074] Obtaining several winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining the optimal winding mode;

[0075] Based on the winding mode to be selected, dividing the air gaps of the first flyback transformer and the second flyback transformer to determine the optimal number of air gap divisions;

[0076] Based on the optimal winding method and the optimal number of air gap divisions, combined with a preset air gap avoidance method, the optimal interleaved anti-laser volt-volt inverter is determined, and the design of the interleaved anti-laser volt-volt inverter is completed.

[0077] As a preferred solution, the step of obtaining several winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining the optimal winding mode includes:

[0078] Acquire several winding modes to be selected, and construct winding loss simulation models of the first flyback transformer and the second flyback transformer;

[0079] The peak switching cycle primary current and secondary current of the first flyback transformer and the second flyback transformer are used as current excitations to simulate the winding loss simulation model to obtain the winding loss of each winding method to be selected;

[0080] Screen the candidate winding method with the largest winding loss reduction value and determine the optimal winding method.

[0081] It can be understood that, compared with the prior art, the present invention determines the optimal winding method by constructing a winding loss simulation model of the first flyback transformer and the second flyback transformer, determines the optimal number of air gap divisions by dividing the air gaps of the first flyback transformer and the second flyback transformer, and determines the optimal interleaved flyback volt-volt inverter based on the optimal winding method and the optimal number of air gap divisions, combined with a preset air gap avoidance method, and completes the design of the interleaved flyback volt-volt inverter. The present invention reduces the winding loss of the flyback transformer and improves the working performance of the interleaved flyback volt-volt inverter by designing the winding method of the flyback transformer, dividing the air gap, and avoiding the air gap. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 : A schematic diagram of the structure of an interleaved anti-light volt inverter provided by an embodiment of the present invention;

[0083] Figure 2 : A schematic diagram of the core structure connection of a staggered anti-laser volt-to-volt inverter provided by an embodiment of the present invention;

[0084] Figure 3 :A flow chart of maximum power point tracking based on the perturbation and observation method provided in an embodiment of the present invention;

[0085] Figure 4 : A flow chart of the steps of a design method of an interleaved anti-light volt inverter provided by an embodiment of the present invention;

[0086] Figure 5 : A schematic diagram of a stacking winding method provided in an embodiment of the present invention;

[0087] Figure 6 : A window magnetic field distribution diagram of a stacked winding method provided in an embodiment of the present invention;

[0088] Figure 7 : A schematic diagram of a sandwich winding method provided in an embodiment of the present invention;

[0089] Figure 8 : A window magnetic field distribution diagram of a sandwich winding method provided in an embodiment of the present invention;

[0090] Fig. 9 : A schematic diagram of an inter leave winding method provided in an embodiment of the present invention;

[0091] Fig.10 : A window magnetic field distribution diagram of an Inter leave winding method provided in an embodiment of the present invention;

[0092] Fig.11 : A distribution diagram of current density and winding thickness change of a stack winding method provided in an embodiment of the present invention;

[0093] Fig.12 : A distribution diagram of current density and winding thickness change of a sandwich winding method provided in an embodiment of the present invention;

[0094] Fig.13 : A distribution diagram of current density and winding thickness change of an inter-leave winding method provided in an embodiment of the present invention;

[0095] Fig.14 : A schematic diagram of a sandwich-wound flyback transformer model provided in an embodiment of the present invention;

[0096] Fig.15 : A schematic diagram of winding loss simulation results of a sandwich winding method provided in an embodiment of the present invention;

[0097] Fig.16 : A schematic diagram of a flyback transformer model with an inter-leave winding method provided in an embodiment of the present invention;

[0098] Fig.17 : A schematic diagram of winding loss simulation results of an inter-leave winding method provided in an embodiment of the present invention;

[0099] Fig.18 : A schematic diagram of the influence of an existing single air gap diffusion flux on winding loss provided by an embodiment of the present invention;

[0100] Fig.19 : A schematic diagram of the effect of a distributed air gap diffusion flux on winding loss provided by an embodiment of the present invention;

[0101] Fig. 20 : A schematic diagram of a winding loss simulation model of a sandwich winding method combined with a magnetic core air gap provided in an embodiment of the present invention;

[0102] Fig.21 : A schematic diagram of winding loss simulation results of a sandwich winding method combined with a magnetic core air gap provided in an embodiment of the present invention;

[0103] Fig. 22 : A schematic diagram of a winding loss simulation model of an inter-leave winding method combined with a magnetic core air gap provided in an embodiment of the present invention;

[0104] Fig.23 : A schematic diagram of the simulation results of winding losses of an inter-leave winding method combined with a magnetic core air gap provided in an embodiment of the present invention;

[0105] Fig.24 : A schematic diagram of a winding air gap avoidance provided by an embodiment of the present invention;

[0106] Fig.25 : A schematic diagram of a simulation model of a sandwich-wound transformer with divided air gaps and winding-avoided air gaps provided in an embodiment of the present invention;

[0107] Fig.26 : A schematic diagram of winding loss simulation results of a sandwich-wound transformer with divided air gaps and windings avoiding air gaps provided in an embodiment of the present invention;

[0108] Fig. 27 : A schematic diagram of a simulation model of an inter-leave winding transformer with air gaps combined with windings avoiding air gaps provided in an embodiment of the present invention;

[0109] Fig.28 : A schematic diagram of the simulation results of winding losses of an inter-leave winding transformer with divided air gaps and winding avoidance air gaps provided in an embodiment of the present invention;

[0110] Among them, 101: flyback transformer module; 102: inverter module; 103: filter module; 104: power supply; 105: power grid; 106: detection module; 107: processor module; 108: drive module; T r1 : The first flyback transformer; D a1 : The first rectifier diode; C s1 : The first capacitor; S m1 : The first slave main switch tube; S r1 : The first auxiliary switch tube; C clamp1 : The first active clamping capacitor; C m1 : The first auxiliary capacitor; D r1 : The first anti-parallel diode; T r2 : The second flyback transformer; D a2 : The second rectifier diode; C s2 : The second capacitor; S m2 : Second slave main switch tube; S r2 : The second auxiliary switch tube; C clamp2 : Second active clamp capacitor: C m2 : The second auxiliary capacitor; D r2 : second anti-parallel diode; first switch tube: S1; second switch tube: S2; third switch tube: S3; fourth switch tube: S4; C0: filter capacitor; L0: filter inductor. DETAILED DESCRIPTION

[0111] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0112] Embodiment 1

[0113] Please refer to Figure 1 , is a structural diagram of an interleaved flyback volt-volt inverter provided in an embodiment of the present invention, which is used to connect a power source 104 and a power grid 105, and includes: a flyback transformer module 101, an inverter module 102 and a filter module 103;

[0114] The flyback transformer module 101 is used to convert the DC voltage and DC current output by the power supply into a sinusoidal half-wave voltage and a sinusoidal half-wave current according to the maximum power point of the power supply; the inverter module 102 is used to convert the sinusoidal half-wave voltage and sinusoidal half-wave current output by the flyback transformer module into an AC voltage and an AC current according to the current phase and voltage phase of the power grid; the filter module 103 is used to filter the AC voltage and AC current output by the inverter module and output them to the power grid; the input end of the flyback transformer module 101 is electrically connected to the output end of the power supply 104; the output end of the flyback transformer module 101 is electrically connected to the input end of the inverter module 102; the output end of the inverter module 102 is electrically connected to the input end of the filter module 103; the output end of the filter module 103 is electrically connected to the power grid 105.

[0115] In this embodiment, the interleaved anti-laser volt-to-volt inverter further includes: a detection module 106, a processor module 107 and a drive module 108;

[0116] The input end of the detection module 106 is electrically connected to the flyback transformer module 101, the inverter module 102, the power supply 104 and the power grid 105; the output end of the detection module 106 is electrically connected to the input end of the processor module 107; the output end of the processor module 107 is electrically connected to the input end of the drive module 108; the output end of the drive module 108 is electrically connected to the flyback transformer module 101 and the inverter module 102; the detection module 106 is used to detect the electrical The processor module 107 is used to obtain the maximum power point of the power supply 104 according to the current and voltage information of the power supply 104, output the transformer drive instruction of the flyback transformer module 101, and obtain the current phase and grid phase of the grid 105 according to the current and voltage information of the grid 105, and output the inverter drive instruction of the inverter module 102; the drive module 108 is used to complete the regulation of the flyback transformer module 101 according to the transformer drive instruction, and complete the regulation of the inverter module 102 according to the inverter drive instruction.

[0117] Please refer to Figure 2 , is a schematic diagram of the core structure connection of an interleaved anti-laser volt-to-volt inverter provided in an embodiment of the present invention.

[0118] In this embodiment, the flyback transformer module includes: a first flyback transformer unit and a second flyback transformer unit;

[0119] The first flyback transformer unit and the second flyback transformer unit are both used to convert the DC voltage output by the power supply into a sinusoidal half-wave voltage and a sinusoidal half-wave current; the sinusoidal half-wave voltage and the sinusoidal half-wave current output by the first flyback transformer unit are 180 degrees out of phase with the sinusoidal half-wave voltage and the sinusoidal half-wave current output by the second flyback transformer unit.

[0120] In this embodiment, if Figure 2 As shown, the first flyback transformer unit includes: a first flyback transformer T r1 , the first rectifier diode D a1 , the first capacitor C s1 , the first slave main switch tube S m1 , the first auxiliary switch tube S r1 , the first active clamp capacitor C clamp1 and the first auxiliary capacitor C m1 ;

[0121] The first active clamping capacitor C clamp1 The first end of the active clamping capacitor C is electrically connected to the first end of the power supply 104; clamp1 The second end of the auxiliary switch tube S r1 The first end of the auxiliary switch tube S is electrically connected; r1The second end of the first flyback transformer T r1 The second end of the primary inductor is electrically connected to the first flyback transformer T r1 The first end of the primary inductor is electrically connected to the first end of the power supply 104; the first slave main switch tube S m1 The first end of the first flyback transformer T r1 The second end of the primary inductor is electrically connected to the first slave main switch tube S m1 The second end of the first auxiliary capacitor C is electrically connected to the second end of the power supply 104; m1 The first end of the first slave main switch tube S m1 The first end of the auxiliary capacitor C m1 The second end of the first slave main switch tube S m1 The second end of the first flyback transformer T r1 The first end of the secondary inductor and the first rectifier diode D a1 The first end of the capacitor C s1 The first end of the first rectifier diode D a1 The second end of the first capacitor C s1 The second end of the first flyback transformer T r1 The second end of the secondary inductor is electrically connected to the first flyback transformer T r1 The second end of the secondary inductor is electrically connected to the input end of the inverter module 102; the first rectifier diode D a1 The second end of is electrically connected to the input end of the inverter module 102.

[0122] In this embodiment, the first auxiliary switch tube S r1 The first anti-parallel diode D r1 The first end of the active clamp capacitor C clamp1 The second end of the first auxiliary switch tube S is electrically connected; r1 The first anti-parallel diode D r1 The second end of the first flyback transformer T r1 The second end of the primary inductor is electrically connected.

[0123] In this embodiment, if Figure 2 As shown, the second flyback transformer unit includes: a second flyback transformer T r2 , the second rectifier diode D a2 , the second capacitor C s2 , the second slave main switch tube S m2 , the second auxiliary switch tube S r2 , the second active clamp capacitor C clamp2 and the second auxiliary capacitor Cm2 ;

[0124] The second active clamping capacitor C clamp2 The first end of the second active clamping capacitor C is electrically connected to the first end of the power supply 104; clamp2 The second end of the auxiliary switch tube S r2 The first end of the second auxiliary switch tube S r2 The second end of the second flyback transformer T r2 The second end of the primary inductor is electrically connected to the second flyback transformer T r2 The first end of the primary inductor is electrically connected to the first end of the power supply 104; the second slave main switch tube S m2 The first end of the second flyback transformer T r2 The second end of the primary inductor is electrically connected to the second slave main switch tube S m2 The second end of the second auxiliary capacitor C is electrically connected to the second end of the power supply 104; m2 The first end of the second slave main switch tube S m2 The first end of the second auxiliary capacitor C m2 The second end of the second slave main switch tube S m2 The second end of the flyback transformer T r2 The first end of the secondary inductor and the second rectifier diode D a2 The first end of the second capacitor C s2 The first end of the second rectifier diode D a2 The second end of the second capacitor C s2 The second end of the second flyback transformer T r2 The second end of the secondary inductor is electrically connected to the second flyback transformer T r2 The second end of the secondary inductor is electrically connected to the input end of the inverter module 102; the second rectifier diode D a2 The second end of is electrically connected to the input end of the inverter module 102.

[0125] In this embodiment, the second auxiliary switch tube S r2 The second anti-parallel diode D r2 The first end of the second active clamp capacitor C clamp2 The second end of the auxiliary switch tube S is electrically connected; r2 The second anti-parallel diode D r2 The second end of the second flyback transformer T r2 The second end of the primary inductor is electrically connected.

[0126] In this embodiment, the working phase of the first flyback transformer and the second flyback transformer is set to 180 degrees, thereby realizing interleaved flyback. By taking turns to conduct the two intermittent mode flyback transformers, the interleaved flyback can effectively reduce the current peak and achieve higher output power at a lower peak current amplitude, thereby greatly reducing the input and output ripple, optimizing the feedback response, and improving the working performance of the interleaved flyback PV inverter.

[0127] In this embodiment, the first flyback transformer T r1 and the second flyback transformer T r2 The winding method of the first flyback transformer T is an alternating winding method; r1 and the second flyback transformer T r2 The air gap is composed of a number of identical sub-air gaps; the first flyback transformer T r1 and the second flyback transformer T r2 There is a mismatch between the winding and the air gap.

[0128] In this embodiment, the winding is performed by an alternating winding method, and the air gap of the first flyback transformer and the second flyback transformer is set to a number of identical sub-air gaps, and the winding and the air gap are not fitted together, thereby reducing the winding loss of the first flyback transformer and the second flyback transformer and improving the working performance of the interleaved flyback PV inverter.

[0129] As a preferred solution, the inverter module 102 includes: a first switch tube S1, a second switch tube S2, a third switch tube S3 and a fourth switch tube S4;

[0130] The first end of the first switch tube S1 is connected to the first rectifier diode D a1 The first end of the first switch tube S1 is electrically connected to the second rectifier diode D a2 The first end of the second switch tube S2 is electrically connected to the first flyback transformer T r1 The second end of the secondary inductor is electrically connected to the first end of the second switch tube S2 and the second flyback transformer T r2 The second end of the secondary inductor is electrically connected to the second end of the secondary inductor; the first end of the third switch tube S3 is electrically connected to the first end of the second switch tube S2; the first end of the fourth switch tube S4 is electrically connected to the first end of the first switch tube S1; the second end of the first switch tube S1 is electrically connected to the input end of the filter module 103; the second end of the second switch tube S2 is electrically connected to the input end of the filter module 103; the second end of the third switch tube S3 is electrically connected to the input end of the filter module 103; the second end of the fourth switch tube S4 is electrically connected to the input end of the filter module 103.

[0131] In this embodiment, the filtering module 103 includes: a filtering capacitor C0 and a filtering inductor L0;

[0132] The first end of the filter inductor L0 is electrically connected to the second end of the first switch tube S1, the second end of the second switch tube S2, the second end of the third switch tube S3 and the second end of the fourth switch tube S4 respectively; the second end of the filter inductor L0 is electrically connected to the power grid 105; the first end of the filter capacitor C0 is electrically connected to the first end of the filter inductor L0; the second end of the filter capacitor C0 is electrically connected to the second end of the first switch tube S1; the second end of the filter capacitor C0 is electrically connected to the second end of the second switch tube S2; the second end of the filter capacitor C0 is electrically connected to the power grid 105.

[0133] In an optional embodiment, since the working modes of the first flyback transformer and the first flyback transformer in the interleaved flyback PV inverter of this embodiment are the same and the phase difference is 180 degrees, only the working principle of the first flyback transformer will be analyzed below, and the working principle of the second flyback transformer is the same as that of the first flyback transformer.

[0134] Specifically, the first stage is from time t0 to time t1. At time t0, the first slave master switch S m1 The DC voltage V of the power supply 104 is turned on. DC Added to the first flyback transformer T r1 The primary current rises linearly on the primary inductor and the energy is stored in the primary inductor. r1 The direction of the induced electromotive force of the secondary winding is negative at the top and positive at the bottom, so the first rectifier diode D a1 Cut-off, the first capacitor C s1 Discharge provides load current;

[0135] The second stage is from t1 to t2. At t1, the first slave main switch S m1 Disconnect, the first flyback transformer T r1 The primary inductance and the first slave main switch tube S m1 The parasitic capacitance of the first flyback transformer T r1 The voltage of the primary inductor rises to V DC +V Clamp , the primary inductance and primary current reach their peak values, after which the first auxiliary switch tube S r1 The first anti-parallel diode D r1 The first flyback transformer T r1 The voltage across the primary side is clamped at -V Clamp , the first slave main switch tube S m1 The drain and source voltages are clamped at V DC +VClamp , thus reducing the switch voltage stress.

[0136] The third stage is at time t2. Since the first slave main switch S m1 and the first auxiliary switch tube S r1 The trigger signals of are complementary, so at time t2 the first rectifier diode D a1 At t2 to t3, the first flyback transformer T r1 The energy of the primary inductor is transferred to the secondary side according to the ampere-turn balance, and then the first auxiliary switch tube S r1 The first active clamp capacitor C clamp1 With the first flyback transformer T r1 The primary leakage inductance resonates, and part of the energy stored in the leakage inductance is transferred to the first active clamping capacitor C clamp1 , part of it is transferred to the secondary output, so that the energy of the leakage inductance can be absorbed and utilized, improving the efficiency of the inverter.

[0137] The fourth stage is from t3 to t4, when the first flyback transformer T r1 The secondary inductor current decreases linearly, and the current and voltage are transmitted to the inverter module 102 and the filter module 103, and then transmitted to the power grid 105.

[0138] It should be noted that in the switching cycle with a small output current, the secondary current is intermittent, so after the current switching cycle ends, the primary current in the next switching cycle starts to rise from 0. In the switching cycle with a large output current, the secondary current is continuous. According to the ampere-turn balance principle, the residual energy on the secondary side is transferred back to the primary side at the end of the switching cycle. The primary current in the next switching cycle starts to rise from a certain value, and the subsequent process is the same as stages one to four. It is worth noting that in the discontinuous mode of the secondary current, when the secondary current is 0, the anti-parallel diode is turned off and the active clamping capacitor is discharged. This does not happen in the continuous mode.

[0139] This interleaved flyback photovoltaic inverter generates a sinusoidal voltage through a flyback transformer and filters out high-order harmonics. The inverter module then inverts the sinusoidal half-wave into a voltage and current in phase with the grid. At the same time, the filter module reduces the impact of differential-mode interference and common-mode interference. The interleaved flyback conversion method can reduce the ripple current passing through the large-capacity input capacitor and extend the service life of the capacitor. In addition, it can also reduce the ripple of the output current, reduce the output current THD, and improve the power quality. Compared with photovoltaic inverters using a single flyback transformer, the interleaved flyback method also improves the inverter power level.

[0140] It should be noted that the maximum power point tracking (MPPT) and the voltage-current output characteristics of solar cells (power sources) will be affected by various factors such as temperature and light intensity. The photovoltaic inverter must ensure that the solar cell operates at the maximum power point to obtain the maximum output electrical energy, which requires the use of maximum power point tracking. In addition, the pulsation of the output voltage of the solar cell must be small enough so that the pulsation of the output current will not be too large when it operates near the maximum power point. The output voltage and output current range of the solar cell are relatively wide. The maximum power point can be determined by changing the resistive load on the battery from 0 (short circuit connection) to the maximum (open circuit state), that is, under this light intensity, the inverter can obtain the maximum power from the battery. There are generally two algorithms for tracking MPP, namely: perturbation observation method and incremental conductance method.

[0141] In an alternative embodiment, please refer to Figure 3 , is a flowchart of a maximum power point tracking based on a perturbation observation method provided by an embodiment of the present invention, such as Figure 3 As shown, setting the MPPT reference represents a disturbance to the solar cell voltage, while MPPTref+ and MPPTref- represent subsequent disturbances in the same or opposite direction, respectively. The set MPPT reference determines the peak value of the sinusoidal current generated by the flyback transformer.

[0142] The present invention converts the DC voltage and DC current output by the power supply into a half-sine wave voltage and a half-sine wave current according to the maximum power point of the power supply through the flyback transformer module, and converts the half-sine wave voltage and the half-sine wave current output by the flyback transformer module into an AC voltage and an AC current according to the current phase and the voltage phase of the power grid. The AC voltage and the AC current output by the inverter module are filtered by the filter module and then output to the power grid, thereby realizing the conversion of the DC voltage and current of the power supply into a voltage and current matching the power grid. The present invention ensures that the power supply works in the best working state by tracking the maximum power point of the power supply, so that the flyback transformer module can obtain the maximum output electric energy, avoids the low working performance of the interlaced flyback volt-volt inverter caused by the influence of temperature and light intensity, and converts the voltage and current again through the inverter module, thereby improving the conversion performance of the interlaced flyback volt-volt inverter for solar energy and the output efficiency to the power grid, and improving the working performance of the interlaced flyback volt-volt inverter.

[0143] Embodiment 2

[0144] Please refer to Figure 4 , which is a step flow chart of a design method of an interleaved anti-light volt-to-volt inverter provided in an embodiment of the present invention, is applicable to an interleaved anti-light volt-to-volt inverter as described in the above embodiment, including: step S201 to step S203.

[0145] Step S201: obtaining several winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining the optimal winding mode.

[0146] Step S202: based on the winding mode to be selected, dividing the air gaps of the first flyback transformer and the second flyback transformer to determine the optimal number of air gap divisions.

[0147] Step S203: Based on the optimal winding mode and the optimal number of air gap divisions, combined with a preset air gap avoidance method, an optimal interleaved anti-laser volt-volt inverter is determined to complete the design of the interleaved anti-laser volt-volt inverter.

[0148] In this embodiment, the step of obtaining several winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining the optimal winding mode includes:

[0149] Obtain several winding methods to be selected, and construct winding loss simulation models of the first flyback transformer and the second flyback transformer; use the peak switching cycle primary current and secondary current of the first flyback transformer and the second flyback transformer as current excitation, simulate the winding loss simulation model, and obtain the winding loss of each winding method to be selected; select the winding method with the largest winding loss reduction value to determine the optimal winding method.

[0150] In this embodiment, based on the optimal winding mode and the optimal number of air gap divisions, combined with a preset air gap avoidance method, an optimal interleaved anti-laser volt-volt inverter is determined, and the design of the interleaved anti-laser volt-volt inverter is completed, specifically including:

[0151] The core air gaps of the first flyback transformer and the second flyback transformer are divided according to the optimal air gap division number; after filling the skeletons of the core air gap positions of the first flyback transformer and the second flyback transformer with non-magnetic material, the cores of the first flyback transformer and the second flyback transformer are wound according to the optimal winding method, the optimal interleaved flyback laser volt-to-volt inverter is determined, and the design of the interleaved flyback laser volt-to-volt inverter is completed.

[0152] In an optional embodiment, the winding methods to be selected include: stacked winding, sandwich winding, and inter leave winding (i.e., alternating winding). When the number of turns and wire diameter of the magnetic core and winding are the same, the winding method has a considerable impact on the winding loss.

[0153] Please refer to Figure 5 , is a schematic diagram of a stacking winding method provided in an embodiment of the present invention, Figure 6 , which is a window magnetic field distribution diagram of a stacked winding method provided in an embodiment of the present invention; Figure 7, is a schematic diagram of a sandwich winding method provided in an embodiment of the present invention, Figure 8 , is a window magnetic field distribution diagram of a sandwich winding method provided in an embodiment of the present invention; Fig. 9 , is a schematic diagram of an Inter leave winding method provided in an embodiment of the present invention, Fig.10 , is a window magnetic field distribution diagram of an Inter leave winding method provided by an embodiment of the present invention. Figures 5 to 10 As shown, the window magnetic field distribution of different winding methods is not the same, among which the maximum magnetic field strength of the inter-leave winding method is 1 / 2 of the sandwich winding method and 1 / 4 of the stacked winding method.

[0154] Please refer to Fig.11 , which is a distribution diagram of current density and winding thickness change of a stack winding method provided in an embodiment of the present invention; Fig.12 , which is a distribution diagram of current density and winding thickness change of a sandwich winding method provided in an embodiment of the present invention; Fig.13 , is a distribution diagram of the current density and winding thickness change of an Inter leave winding method provided by an embodiment of the present invention. Figures 11 to 13 As shown, the current density of the Inter leave winding method is the most uniform among the three winding methods.

[0155] Based on the formula It can be concluded that the Inter leave winding method can reduce winding losses.

[0156] In an optional embodiment, the Ansoft models of sandwich winding and inter leave winding are established respectively, and the peak switching cycle primary current and secondary current of the flyback transformer in the photovoltaic inverter are used as current excitation for simulation. Fig.14 , is a schematic diagram of a sandwich-wound flyback transformer model provided in an embodiment of the present invention, Fig.15 , is a schematic diagram of winding loss simulation results of a sandwich winding method provided in an embodiment of the present invention, Fig.16 , is a schematic diagram of an inter-leave flyback transformer model provided in an embodiment of the present invention, Fig.17 , is a schematic diagram of winding loss simulation results of an inter-leave winding method provided in an embodiment of the present invention.

[0157] like Fig.15 As shown in Figure 2, the winding loss of the sandwich-wound transformer is 3.94W; Fig.16 As shown in the figure, the winding loss of the transformer with inter-leave winding method is 3.42 W. From the simulation results, the winding loss of the transformer can be reduced to 86.64% of the original value by using the inter-leave winding method.

[0158] It should be noted that in a core made of high permeability material without air gaps, the windings are evenly distributed, so the magnetic potential difference between points along the magnetic path is not large, resulting in a small diffuse flux. Similarly, in a core made of magnetic powder core material, the air gap is evenly distributed throughout the core, and the diffuse flux is minimal at this time.

[0159] Please refer to Fig.18 , which is a schematic diagram of the influence of an existing single air gap diffuse magnetic flux on winding loss provided by an embodiment of the present invention. In the flyback transformer designed in the prior art, in order to reduce the inductance and prevent the core from saturating, an air gap is opened in the middle column of the core. This method makes the transformer less susceptible to EMI interference from external components. However, at this time, the magnetic voltage drop of the entire coil is added to the air gap, and most of the magnetic field energy is stored in the air gap. There is a serious diffuse magnetic flux at the edge of the air gap and the magnetic path nearby. This part of the diffuse magnetic flux cuts the winding wire at high frequency, generating induced eddy current in it, and the resulting eddy current loss is very large.

[0160] In an alternative embodiment, please refer to Fig.19 , is a schematic diagram of the influence of a distributed air gap diffusion flux on winding loss provided by an embodiment of the present invention. Fig.19 As shown in FIG. 1 , this embodiment adopts a method of replacing a single large air gap with multiple uniformly distributed small air gaps. When the overall air gap length remains unchanged, the inductance of the transformer does not change. Because the smaller the air gap, the shorter the diffusion distance of the edge magnetic flux in the winding window. Then, the diffusion magnetic flux of each small air gap will be much lower than before, and the eddy current loss of the winding caused will also be reduced accordingly.

[0161] In an alternative embodiment, please refer to Fig. 20 , is a schematic diagram of a winding loss simulation model of a sandwich winding method combined with a magnetic core divided air gap provided in an embodiment of the present invention, Fig.21 , which is a schematic diagram of winding loss simulation results of a sandwich winding method combined with a magnetic core divided air gap provided in an embodiment of the present invention; Fig. 22 , is a schematic diagram of a winding loss simulation model of an inter-leave winding method combined with a magnetic core divided air gap provided in an embodiment of the present invention, Fig.23 , which is a schematic diagram of the winding loss simulation results of an Interleave winding method combined with a magnetic core air gap provided in an embodiment of the present invention.

[0162] like Figure 20 to Figure 23As shown, the more divided air gaps there are, the more complex and difficult the manufacturing process is, and the less obvious the reduction in winding loss is. In this embodiment, the original air gap of the transformer is divided into two equal parts, while the total length remains unchanged. The winding loss simulation result of the sandwich winding method combined with the divided air gap of the magnetic core is 3.16W; the winding loss simulation result of the inter leave winding method combined with the divided air gap of the magnetic core is 2.61W.

[0163] It should be noted that another way to reduce the influence of diffuse flux on winding loss is to adopt air gap avoidance. Under high-frequency working conditions, if the transformer winding is arranged near the air gap, the eddy current loss caused by diffuse flux will increase significantly. The greater the distance between the winding and the air gap, the smaller the loss. When the distance between the winding and the magnetic core is about 3 times the length of the air gap, the winding loss caused by diffuse flux will be sharply reduced, which is less than 10% of the loss when the same winding is arranged near the air gap. Therefore, when designing the winding structure, it is appropriate to make the coil avoid the air gap with a certain space distance. This arrangement will inevitably reduce the filling factor of the conductor window, or increase the length of the winding, and the DC resistance will increase accordingly, but it can greatly promote the reduction of the AC loss of the winding. Selecting the magnetic lines of force of the static diffuse flux located at three times the length of the air gap as the perimeter of the avoidance area can quickly and conveniently confirm the winding avoidance area.

[0164] In an alternative embodiment, please refer to Fig.24 , which is a schematic diagram of a winding air gap avoidance provided in an embodiment of the present invention; in this embodiment, by filling the frame at the air gap position of the magnetic core with non-magnetic material and then winding the coil, or making the transformer frame into a convex middle column part, not only a certain distance is made from the air gap, but also the coil can be wound in a normal manner.

[0165] In an alternative embodiment, please refer to Fig.25 , which is a schematic diagram of a simulation model of a sandwich-wound transformer with divided air gaps and winding-avoiding air gaps provided in an embodiment of the present invention; Fig.26 , which is a schematic diagram of winding loss simulation results of a sandwich-wound transformer with divided air gaps combined with windings avoiding air gaps provided by an embodiment of the present invention; Fig. 27 , which is a schematic diagram of a simulation model of an inter-leave winding transformer with divided air gaps and winding-avoiding air gaps provided in an embodiment of the present invention; Fig.28 , which is a schematic diagram of the winding loss simulation results of an inter-leave winding transformer with divided air gaps combined with winding avoidance air gaps provided in an embodiment of the present invention.

[0166] like Figure 25 to Figure 28As shown, the winding loss simulation result of the sandwich winding core air gap plus winding air gap avoidance transformer is 2.57W, and the winding loss simulation result of the inter leave winding plus core air gap and winding air gap avoidance transformer is 2.03W.

[0167] Based on the simulation results of the above optional embodiments, please refer to Table 1, which is a summary table of simulation results of transformer winding losses with different winding methods and different magnetic core air gap treatments provided by the embodiments of the present invention. From the simulation results of losses, Inter leave winding, distributed air gaps, and winding air gap avoidance can all play a good role in reducing winding losses. At the same time, the loss reduction effect of using Inter leave winding plus magnetic core distributed air gaps and air gap avoidance is the best. At this time, the winding loss is only 2.03W, which is 51.52% of the original transformer. Therefore, it can be used to improve the working efficiency of photovoltaic inverters.

[0168] Table 1

[0169]

[0170] In an optional embodiment, based on the optimal winding mode and the optimal number of air gap divisions, combined with a preset air gap avoidance method, an optimal interleaved anti-laser volt-volt inverter is determined, and the design of the interleaved anti-laser volt-volt inverter is completed, specifically including:

[0171] Winding Inter leave structure flyback transformer: The 8 turns of the primary side of the flyback transformer are divided into two parts of 4 turns + 4 turns, and the 64 turns of the secondary side are divided into three parts of 21 turns + 21 turns + 22 turns. The windings are arranged in the order of secondary side - primary side - secondary side - primary side - secondary side. The primary layer and the secondary layer are shielded with 3 layers of insulating tape.

[0172] Change the size of the air gap in the core column to increase the inductance of the primary side of the transformer to 31uH. Perform winding air gap avoidance treatment, that is, fill the skeleton at the position of the core air gap with non-magnetic materials, such as insulating tape, and then wind the coil, or make the middle column of the transformer skeleton convex.

[0173] This embodiment determines the optimal winding method by constructing a winding loss simulation model of the first flyback transformer and the second flyback transformer, and determines the optimal number of air gap divisions by dividing the air gaps of the first flyback transformer and the second flyback transformer. Based on the optimal winding method and the optimal number of air gap divisions, combined with a preset air gap avoidance method, the optimal interleaved flyback volt-volt inverter is determined to complete the design of the interleaved flyback volt-volt inverter. This embodiment reduces the winding loss of the flyback transformer and improves the working performance of the interleaved flyback volt-volt inverter by designing the winding method of the flyback transformer, dividing the air gap, and avoiding the air gap.

[0174] In summary, in the first aspect, the embodiment of the present invention converts the DC voltage and DC current output by the power supply into a half-sine wave voltage and a half-sine wave current according to the maximum power point of the power supply through the flyback transformer module, and converts the half-sine wave voltage and the half-sine wave current output by the flyback transformer module into an AC voltage and an AC current according to the current phase and the voltage phase of the power grid. The AC voltage and the AC current output by the inverter module are filtered by the filter module and then output to the power grid, thereby realizing the conversion of the DC voltage and current of the power supply into a voltage and current matching the power grid. The embodiment of the present invention ensures that the power supply works in the best working state by tracking the maximum power point of the power supply, so that the flyback transformer module can obtain the maximum output electric energy, avoids the low working performance of the interlaced flyback volt-volt inverter caused by the influence of temperature and light intensity, and converts the voltage and current again through the inverter module, thereby improving the conversion performance of the interlaced flyback volt-volt inverter for solar energy and the output efficiency to the power grid, and improving the working performance of the interlaced flyback volt-volt inverter. On the other hand, the embodiment of the present invention determines the optimal winding method by constructing a winding loss simulation model of the first flyback transformer and the second flyback transformer, determines the optimal number of air gap divisions by dividing the air gaps of the first flyback transformer and the second flyback transformer, and determines the optimal interleaved flyback volt-volt inverter based on the optimal winding method and the optimal number of air gap divisions in combination with a preset air gap avoidance method, thereby completing the design of the interleaved flyback volt-volt inverter. This embodiment reduces the winding loss of the flyback transformer and improves the working performance of the interleaved flyback volt-volt inverter by designing the winding method of the flyback transformer, dividing the air gap, and avoiding the air gap.

[0175] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. An interleaved anti-light volt inverter, characterized in that: Used to connect the power supply and the power grid, including: flyback transformer module, inverter module and filter module; The flyback transformer module is used to convert the DC voltage and DC current output by the power supply into a half-sine wave voltage and a half-sine wave current according to the maximum power point of the power supply; The inverter module is used to convert the half-sine wave voltage and half-sine wave current output by the flyback transformer module into an alternating current voltage and an alternating current according to the current phase and the voltage phase of the power grid; The filtering module is used to filter the AC voltage and AC current output by the inverter module and then output them to the power grid.

2. The interleaved anti-light volt inverter according to claim 1, characterized in that: The flyback transformer module comprises: a first flyback transformer unit and a second flyback transformer unit; The first flyback transformer unit and the second flyback transformer unit are both used to convert the DC voltage output by the power supply into a half-sine wave voltage and a half-sine wave current; The phase difference between the half-sine wave voltage and the half-sine wave current output by the first flyback transformer unit and the half-sine wave voltage and the half-sine wave current output by the second flyback transformer unit is 180 degrees.

3. The interleaved anti-light volt inverter according to claim 2, characterized in that: The first flyback transformer unit includes: a first flyback transformer, a first rectifier diode, a first capacitor, a first slave main switch tube, a first auxiliary switch tube, a first active clamp capacitor and a first auxiliary capacitor; A first end of the first active clamping capacitor is electrically connected to a first end of the power supply; The second end of the first active clamping capacitor is electrically connected to the first end of the first auxiliary switch tube; The second end of the first auxiliary switch tube is electrically connected to the second end of the primary inductor of the first flyback transformer; A first end of the primary inductor of the first flyback transformer is electrically connected to a first end of the power supply; The first end of the first slave main switch is electrically connected to the second end of the primary inductor of the first flyback transformer; The second end of the first slave main switch is electrically connected to the second end of the power supply; The first end of the first auxiliary capacitor is electrically connected to the first end of the first slave main switch tube; The second end of the first auxiliary capacitor is electrically connected to the second end of the first slave main switch tube; A first end of the secondary inductor of the first flyback transformer is electrically connected to a first end of the first rectifier diode; The first end of the first capacitor is electrically connected to the second end of the first rectifier diode; The second end of the first capacitor is electrically connected to the second end of the secondary inductor of the first flyback transformer; The second end of the secondary inductor of the first flyback transformer is electrically connected to the input end of the inverter module; The second end of the first rectifier diode is electrically connected to the input end of the inverter module.

4. The interleaved anti-light volt-to-volt inverter according to claim 3, characterized in that: The second flyback transformer unit includes: a second flyback transformer, a second rectifier diode, a second capacitor, a second slave main switch tube, a second auxiliary switch tube, a second active clamping capacitor and a second auxiliary capacitor; A first end of the second active clamping capacitor is electrically connected to a first end of the power supply; The second end of the second active clamping capacitor is electrically connected to the first end of the second auxiliary switch tube; The second end of the second auxiliary switch tube is electrically connected to the second end of the primary inductor of the second flyback transformer; A first end of the primary inductor of the second flyback transformer is electrically connected to a first end of the power supply; The first end of the second slave main switch is electrically connected to the second end of the primary inductor of the second flyback transformer; The second end of the second slave main switch is electrically connected to the second end of the power supply; The first end of the second auxiliary capacitor is electrically connected to the first end of the second slave main switch tube; The second end of the second auxiliary capacitor is electrically connected to the second end of the second slave main switch tube; A first end of the secondary inductor of the second flyback transformer is electrically connected to a first end of the second rectifier diode; The first end of the second capacitor is electrically connected to the second end of the second rectifier diode; The second end of the second capacitor is electrically connected to the second end of the secondary inductor of the second flyback transformer; The second end of the secondary inductor of the second flyback transformer is electrically connected to the input end of the inverter module; The second end of the second rectifier diode is electrically connected to the input end of the inverter module.

5. The interleaved anti-light volt-to-volt inverter according to claim 4, characterized in that: The winding method of the first flyback transformer and the second flyback transformer is an alternating winding method; The air gaps of the first flyback transformer and the second flyback transformer are composed of a plurality of identical sub-air gaps; The windings of the first flyback transformer and the second flyback transformer are not in contact with the air gap.

6. The interleaved anti-light volt-to-volt inverter according to claim 4, characterized in that: The inverter module includes: a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; The first end of the first switch tube is electrically connected to the second end of the first rectifier diode; The first end of the first switch tube is electrically connected to the second end of the second rectifier diode; The first end of the second switch tube is electrically connected to the second end of the secondary inductor of the first flyback transformer; The first end of the second switch tube is electrically connected to the second end of the secondary inductor of the second flyback transformer; The first end of the third switch tube is electrically connected to the first end of the second switch tube; The first end of the fourth switch tube is electrically connected to the first end of the first switch tube; The second end of the first switch tube is electrically connected to the input end of the filter module; The second end of the second switch tube is electrically connected to the input end of the filter module; The second end of the third switch tube is electrically connected to the input end of the filter module; The second end of the fourth switch tube is electrically connected to the input end of the filter module.

7. The interleaved anti-light volt-to-volt inverter according to claim 6, characterized in that: The filtering module includes: a filtering capacitor and a filtering inductor; The first end of the filter inductor is electrically connected to the second end of the first switch tube, the second end of the second switch tube, the second end of the third switch tube and the second end of the fourth switch tube respectively; The second end of the filter inductor is electrically connected to the power grid; The first end of the filter capacitor is electrically connected to the first end of the filter inductor; The second end of the filter capacitor is electrically connected to the second end of the first switch tube; The second end of the filter capacitor is electrically connected to the second end of the second switch tube; The second end of the filter capacitor is electrically connected to the power grid.

8. The interleaved anti-light volt-to-volt inverter according to claim 6, characterized in that: Also includes: Detection module, processor module and driver module; The input end of the detection module is electrically connected to the flyback transformer module, the inverter module, the power supply and the power grid; The output end of the detection module is electrically connected to the input end of the processor module; The output end of the processor module is electrically connected to the input end of the driving module; The output end of the driving module is electrically connected to the flyback transformer module and the inverter module; The detection module is used to detect the current and voltage information of the power supply and the power grid; The processor module is used to obtain the maximum power point of the power supply according to the current and voltage information of the power supply, output the transformer drive instruction of the flyback transformer module, and obtain the current phase and grid phase of the grid according to the current and voltage information of the grid, and output the inverter drive instruction of the inverter module; The driving module is used to complete the regulation of the flyback transformer module according to the transformer driving instruction, and to complete the regulation of the inverter module according to the inverter driving instruction.

9. A design method for an interleaved reverse volt-to-volt inverter, characterized in that: An interleaved photovoltaic inverter according to any one of claims 1 to 8, comprising: Obtaining several winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining the optimal winding mode; Based on the winding mode to be selected, dividing the air gaps of the first flyback transformer and the second flyback transformer to determine the optimal number of air gap divisions; Based on the optimal winding method and the optimal number of air gap divisions, combined with a preset air gap avoidance method, the optimal interleaved anti-laser volt-volt inverter is determined, and the design of the interleaved anti-laser volt-volt inverter is completed.

10. The design method of the interleaved photovoltaic inverter according to claim 9, characterized in that: The step of obtaining a plurality of winding modes to be selected, constructing winding loss simulation models of the first flyback transformer and the second flyback transformer, and determining an optimal winding mode includes: Acquire several winding modes to be selected, and construct winding loss simulation models of the first flyback transformer and the second flyback transformer; The peak switching cycle primary current and secondary current of the first flyback transformer and the second flyback transformer are used as current excitations to simulate the winding loss simulation model to obtain the winding loss of each winding method to be selected; Screen the candidate winding method with the largest winding loss reduction value and determine the optimal winding method.

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