High-boost converter based on coupled inductor and charging pile

Abstract

The present application relates to a high-boost converter based on a coupled inductor, which overcomes the disadvantages of traditional Boost converters that it is difficult to achieve a high voltage conversion ratio and high conversion efficiency. A coupled inductor is added to the converter circuit. By adjusting the turns ratio between the primary winding and each secondary winding of the first coupled inductor, a high voltage conversion ratio and high voltage output are obtained; the boost function is realized by adjusting the duty cycle of the switching tube, avoiding the switching tube working under extreme duty cycle conditions; the voltage stress that the switching tube needs to bear is relatively low, reducing the performance requirements for components such as the switching tube, and it can be better applied to the power system of new energy charging piles.

Description

Technical Field

[0001] The present application relates to the technical field of converters, and particularly to a high-boost converter and a charging pile based on a coupled inductor. Background Art

[0002] New energy vehicles have the advantages of high energy efficiency, low gas pollution, low noise, and low operating costs. In recent years, they have been developing better and better. As the link between new energy vehicles and the power grid, charging piles can promote the transformation of the energy structure to clean energy. The power electronic converter of the charging pile plays an important role in electric energy conversion and is the key to the charging pile.

[0003] The traditional Boost converter has a simple structure and is easy to implement. Its voltage gain under extreme duty cycle conditions can be infinite, and theoretically it can be applied to occasions where the voltage level needs to be increased. However, the voltage stress across the switching tube is the output voltage. When operating under a high duty cycle condition, the switching tube needs to withstand a high voltage stress, which poses a challenge to the voltage withstand performance of the switching tube. In addition, the current of the diode is pulsating, which will cause a large output voltage ripple. Therefore, in the actual application process, the traditional Boost converter cannot achieve high voltage output and cannot meet the high voltage conversion requirements of new energy charging piles. Summary of the Invention

[0004] Based on this, the present application provides a high-boost converter and a charging pile based on a coupled inductor. Under the condition of obtaining a high voltage conversion ratio and high electric energy conversion efficiency, it can avoid the switching tube from operating under extreme duty cycle conditions, reduce the performance requirements for components such as the switching tube, and can be better applied to new energy charging piles.

[0005] An embodiment of the present application provides a high-boost converter based on a coupled inductor, including a converter circuit. The converter circuit includes: an input power supply V in , a switching tube S1, a first inductor L, a first diode D1, a second diode D2, a coupled inductor T1, a first capacitor C1, a second capacitor C2, and a third capacitor C3. Among them, the coupled inductor T1 includes an exciting inductor L m , a primary winding N1, a first secondary winding N2, and a second secondary winding N3; the first end of the input power supply V in is connected to the first end of the first inductor L; the second end of the first inductor L is connected to the second end of the first capacitor C1, the first end of the exciting inductor L m of the coupled inductor T1, the first end of the primary winding N1 of the coupled inductor T1, and the anode of the first diode D1; the exciting inductor L mThe second end of the is connected to the second end of the primary winding N1 of the coupled inductor T1, the first end of the second secondary winding N3 of the coupled inductor T1, and the first end of the switching transistor S1; the cathode of the first diode D1 is connected to the second end of the first secondary winding N2 of the coupled inductor T1; the second end of the second secondary winding N3 of the coupled inductor T1 is connected to the second end of the second capacitor C2; the first end of the second capacitor C2 is connected to the first end of the first secondary winding N2 of the coupled inductor T1 and the anode of the second diode D2; the cathode of the second diode D2 is connected to the first end of the third capacitor C3 and forms a first load terminal; the input power supply V in The second end of the is connected to the first end of the first capacitor C1, the second end of the switching transistor S1, and the second end of the third capacitor C3 and forms a second load terminal; the first load terminal and the second load terminal are used to connect to a DC load R; the third end of the switching transistor S1 is used to be connected to the output end of the control module, and the switching transistor S1 receives and is turned on in a timely manner according to the switching control signal output by the control module to drive the converter circuit to work to achieve high step-up.

[0006] In an optional embodiment, the control module is further included, and the control module includes an A / D conversion unit, a neural network controller, and a PWM unit that are connected in sequence; the A / D conversion unit is used to collect the output voltage signals of the first load terminal and the second load terminal, the first current signal flowing through the first inductor L, and the second current signal flowing through the exciting inductor L m The second current signal is converted into a digital sampling signal and transmitted to the neural network controller; the neural network controller receives the digital sampling signal, performs a weighted summation operation on the digital sampling signal through a trained neural network model to obtain a switching duty ratio for controlling the operation of the converter circuit, and inputs it into the PWM unit; the PWM unit receives and generates a switching control signal according to the switching duty ratio and transmits it to the switching transistor S1 of the converter circuit to drive it to be turned on in a timely manner to drive the converter circuit to work to achieve high step-up.

[0007] In an optional embodiment, the training method of the neural network model is: establishing a converter discrete model according to the topological structure of the converter circuit; obtaining the output voltage state quantity of the converter circuit at the previous moment, the first current state quantity flowing through the first inductor L, and the second current state quantity flowing through the exciting inductor L m The second current signal is input into the converter discrete model; the converter discrete model, based on the output voltage state quantity, the first current state quantity, and the second current state quantity at the previous moment, combines the corresponding objective function constraint conditions to solve and obtain the control laws corresponding to different operating points, and inputs them into the initial neural network model for training to obtain the neural network model.

[0008] In an alternative embodiment, the control laws corresponding to different operating points are obtained by solving the matrix equation of the discrete model of the converter.

[0009] The matrix equation is: where a is the current time, a - 1 is the previous time, i L (a) is the inductor current flowing through the first inductor L at time a, i Lm (a) is the magnetizing inductor current flowing through the exciting inductor L m at time a, V o (a) is the output voltage of the converter circuit at time a, i L (a - 1) is the first current state variable of the current flowing through the first inductor L at the previous time, i Lm (a - 1) is the second current state variable of the current flowing through the exciting inductor L at the previous time m at time a, V o (a - 1) is the output voltage state variable of the converter circuit at the previous time, a ij is the matrix coefficient a 11 to a 33 , a ij where i = 1, 2, 3 in a ij and j = 1, 2, 3 in a ij are determined by the circuit parameters and control strategy of the converter circuit, b i is the matrix coefficient used to reflect the influence of input variables on the system state, and D(a - 1) is the disturbance variable at the previous time, which is determined by the external disturbance of the converter circuit.

[0010] In an alternative embodiment, the method for obtaining the switching duty ratio is as follows: through the hidden layer of the neural network model, using the corresponding activation function, perform a weighted summation operation on the digital sampling signal to obtain the hidden layer output value h n ,

[0011] where w mn is the weight between the m - th neuron of the input layer and the n - th neuron of the hidden layer, M is the number of neurons in the input layer, b n is the bias value of the n - th neuron of the hidden layer, δ n is the activation function, and N is the number of neurons in the hidden layer;

[0012] Through the output layer of the neural network model, using the corresponding activation function, perform a weighted summation operation on the hidden layer output value h n to obtain the switching duty ratio D o , and the calculation method is: Among them, w n is the weight between the nth neuron of the hidden layer and the neuron of the output layer, b is the bias value of the output layer, and δ o is the activation function.

[0013] In an optional embodiment, the turn ratio of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is A; the turn ratio of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is B.

[0014] In an optional embodiment, the voltage gain of the converter circuit is: Among them, M1 is the voltage gain of the converter circuit, D S is the duty cycle of the switching transistor S1, n1 is the turn ratio A of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1, and m1 is the turn ratio B of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1.

[0015] In an optional embodiment, the input power supply V in is a new energy power supply.

[0016] Another embodiment of the present application provides a charging pile, including the high-boost converter based on a coupled inductor described in the above embodiment.

[0017] The high-boost converter based on a coupled inductor of the present application overcomes the disadvantages of the traditional Boost converter that it is difficult to achieve a high voltage conversion ratio and high conversion efficiency. A coupled inductor is added to the converter circuit. By adjusting the turn ratio between the primary winding and each secondary winding of the first coupled inductor, a high voltage conversion ratio and high voltage output are obtained, avoiding the switching transistor from working under extreme duty cycle conditions, and can be better applied to the power system of new energy charging piles.

[0018] Furthermore, the strategy of using a neural network fitting model to predict the control law is adopted to improve the dynamic performance of the converter and reduce the disturbances caused by changes in the input voltage and load. Description of the Drawings

[0019] Figure 1 is a schematic structural diagram of a high-boost converter based on a coupled inductor in an embodiment of the present application.

[0020] Figure 2 is a schematic control diagram of a high-boost converter based on a coupled inductor in an embodiment of the present application.

[0021] Figure 3In an embodiment of the present application, it is a training schematic diagram of a neural network model.

[0022] Figure 4 In an embodiment of the present application, it is a first-mode schematic diagram of the equivalent circuit of a converter circuit.

[0023] Figure 5 In an embodiment of the present application, it is a second-mode schematic diagram of the equivalent circuit of a converter circuit.

[0024] Figure 6 In an embodiment of the present application, it is a third-mode schematic diagram of the equivalent circuit of a transformed circuit.

[0025] Figure 7 In an embodiment of the present application, it is a working waveform diagram of the main devices of a converter circuit. Detailed implementation manners

[0026] To make the above objects, features, and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0027] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. Unless otherwise defined, the technical terms or scientific terms used in the present application should have the ordinary meaning understood by those of ordinary skill in the art to which the present application belongs. The "first", "second", and similar terms used in the specification and claims of the present application do not indicate any order, quantity, or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not indicate a quantity limitation, but indicate the existence of at least one. "Multiple" or "several" means at least two. Unless otherwise specified, terms such as "front part", "rear part", "lower part", and / or "upper part" are only for convenience of description and are not limited to one position or a spatial orientation. The terms "including" or "comprising" and similar terms mean that the elements or items appearing before "including" or "comprising" cover the elements or items listed after "including" or "comprising" and their equivalents, and do not exclude other elements or items. The terms "connected" or "coupled" and similar terms are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect.

[0028] As used in the specification of this application and the appended claims, the singular forms "a", "the", and "said" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0029] A high-boost converter based on a coupled inductor provided by an embodiment of this application can be applied to a charging pile in a new energy power system, and the new energy power system may include a solar power generation system, a wind power generation system, or a photovoltaic power generation system.

[0030] As Figure 1 and Figure 2 shown, the high-boost converter based on a coupled inductor includes a converter circuit 11 and a control module 12; the converter circuit 11 includes: an input power supply V in , a switching tube S1, a first inductor L, a first diode D1, a second diode D2, a coupled inductor T1, a first capacitor C1, a second capacitor C2, and a third capacitor C3, where the coupled inductor T1 includes an exciting inductor L m , a primary winding N1, a first secondary winding N2, and a second secondary winding N3.

[0031] In the topology design of the converter circuit, the first end of the input power supply V in is connected to the first end of the first inductor L; the second end of the first inductor L is connected to the second end of the first capacitor C1, the first end of the exciting inductor L m of the coupled inductor T1, the first end of the primary winding N1 of the coupled inductor T1, and the anode of the first diode D1; the second end of the exciting inductor L m of the coupled inductor T1 is connected to the second end of the primary winding N1 of the coupled inductor T1, the first end of the second secondary winding N3 of the coupled inductor T1, and the first end of the switching tube S1; the cathode of the first diode D1 is connected to the second end of the first secondary winding N2 of the coupled inductor T1; the second end of the second secondary winding N3 of the coupled inductor T1 is connected to the second end of the second capacitor C2; the first end of the second capacitor C2 is connected to the first end of the first secondary winding N2 of the coupled inductor T1 and the anode of the second diode D2; the cathode of the second diode D2 is connected to the first end of the third capacitor C3 and forms a first load terminal; the second end of the input power supply V in is connected to the first end of the first capacitor C1, the second end of the switching tube S1, and the second end of the third capacitor C3 and forms a second load terminal.

[0032] The first load terminal and the second load terminal are used to connect a DC load R.

[0033] The third terminal of the switching transistor S1 is used to connect to the output terminal of the control module 12. The switching transistor S1 receives and conducts timely according to the switching control signal output by the control module 12, enabling the converter circuit 11 to operate in different modes, obtaining a high voltage gain, and obtaining a high voltage output.

[0034] In this embodiment, the high-boost converter based on the coupled inductor overcomes the disadvantages of the traditional Boost converter that it is difficult to achieve a high voltage conversion ratio and high conversion efficiency. A coupled inductor is added to the converter circuit. By adjusting the turn ratio between the primary winding and each secondary winding of the first coupled inductor, a high voltage conversion ratio and a high voltage output are obtained, avoiding the switching transistor from working under extreme duty cycle conditions, reducing the performance requirements for components such as the switching transistor, and being able to be better applied to the power system of new energy charging piles.

[0035] In this embodiment, the input power supply V in can be a power generation power supply or a storage power supply (chargeable and dischargeable power supply) in a new energy power system.

[0036] In an optional embodiment, as Figure 2 shown, the control module 12 controls the switching transistor S1 of the converter circuit 11 to conduct timely to achieve high-boost, realizes the selection of different turn ratios of the coupled inductor in the converter circuit 11, and the converter circuit switches working modes when the switching transistor S1 switches, obtaining a high voltage conversion ratio and a high voltage output.

[0037] The control module 12 includes an A / D conversion unit 121, a neural network controller 122, and a PWM unit 123 connected in sequence.

[0038] The A / D conversion unit has a voltage sampling terminal, a first current sampling terminal, and a second current sampling terminal. The voltage sampling terminal is used to collect the output voltage signals of the first load terminal and the second load terminal. The first current sampling terminal is used to collect the first current signal flowing through the first inductor L. The second current sampling terminal is used to collect the second current signal flowing through the exciting inductor L m . The A / D conversion unit converts the output voltage signal, the first current signal, and the second current signal into digital sampling signals and transmits them to the neural network controller.

[0039] The input terminal of the neural network controller is connected to the output terminal of the A / D conversion unit to receive the digital sampling signals. The output terminal of the neural network controller is connected to the PWM unit. The neural network controller receives the digital sampling signals, performs a weighted summation operation on the digital sampling signals through a trained neural network model, obtains the switching duty cycle for controlling the operation of the converter circuit, and inputs it to the PWM unit.

[0040] The PWM unit receives and generates a switching control signal according to the switching duty ratio, and transmits it to the third terminal of the switching transistor S1 of the converter circuit to drive it to conduct timely, thereby driving the converter circuit to work in different modes to achieve high step-up.

[0041] Optionally, as Figure 3 shown, the training method of the neural network model is: establishing a converter discrete model according to the topological structure of the converter circuit; obtaining the output voltage state quantity of the converter circuit at the previous moment, the first current state quantity flowing through the first inductor L, and the second current state quantity flowing through the exciting inductor L m , and inputting them into the converter discrete model; the converter discrete model is based on the output voltage state quantity, the first current state quantity, and the second current state quantity at the previous moment, combined with the corresponding objective function constraint conditions, to solve and obtain the control laws corresponding to different operating points, and input them into the initial neural network model for training to obtain the neural network model.

[0042] Optionally, the control laws corresponding to different operating points are obtained by solving the matrix equation of the converter discrete model. The matrix equation is: The objective function constraint conditions are:

[0043] In the matrix equation, a is the current moment, a - 1 is the previous moment, i L (a) is the inductor current flowing through the first inductor L at moment a, i Lm (a) is the magnetizing inductor current flowing through the exciting inductor L m at moment a, V o (a) is the output voltage of the converter circuit at moment a.

[0044] is the state quantity at the previous moment, including the first current state quantity o L (a - 1) flowing through the first inductor L at the previous moment, the second current state quantity i m flowing through the exciting inductor L Lm , and the output voltage state quantity V o (a - 1) of the converter circuit.

[0045] is the coefficient matrix, that is, a ij is the matrix coefficient a 11 to a 33 , a ij where j = 1, 2, 3 in a ij where j = 1, 2, 3 in a ijDetermined by the circuit parameters (such as inductance, capacitance, resistance, etc.) of the converter circuit and the control strategy. a ij The coefficient reflects the mutual relationship between the system state variables. For example, a 11 、a 12 and a 13 describe the relationship between the inductor current i L (a) at the current moment and the inductor current i L (a - 1) at the previous moment, the magnetizing inductor current i Lm (a - 1), and the output voltage V o (a - 1).

[0046] Are input variables, determined by external inputs (such as input voltage, control signal, etc.). b i The matrix coefficients reflect the influence of the input variables on the system state. For example, b1, b2, and b3 describe the influence of the control signal D(a - 1) on the inductor current i L (a), the magnetizing inductor current i Lm (a), and the output voltage V o (a). D(a - 1) is the disturbance variable at the previous moment, determined by the external interference of the converter circuit.

[0047] The discrete model of the converter can solve the state variables [i L (a - 1), i Lm (a - 1), V o (a - 1)] and the control variable D(a - 1) at the known previous moment, and obtain the state variables [i L (a), i Lm (a), V o (a)] at the current moment, and obtain the control laws corresponding to different operating points.

[0048] This matrix equation describes the dynamic behavior of the converter in discrete time. By iterative solution, the response characteristics of the system under different control strategies, such as stability, convergence, etc., can be analyzed. According to this model, a suitable controller can be designed to meet the objective function constraint conditions. Optionally, a controller can be designed to ensure that the inductor current i L (a), the magnetizing inductor current i Lm (a), and the output voltage V o (a) are within the specified range, thereby realizing system optimization, meeting specific performance indicators, and ensuring that the system operates within a safe and effective range.

[0049] Optionally, the method for obtaining the switching duty cycle is: through the hidden layer of the neural network model, using the corresponding activation function, perform a weighted summation operation on the digital sampling signal to obtain the hidden layer output value h n : where w mn is the weight between the m-th neuron in the input layer and the n-th neuron in the hidden layer, M is the number of neurons in the input layer, b n is the bias value of the n-th neuron in the hidden layer, δ n is the activation function, N is the number of neurons in the hidden layer; through the output layer of the neural network model, using the corresponding activation function, the output value h n of the hidden layer is subjected to a weighted summation operation to obtain the switching duty cycle D o : where w n is the weight between the n-th neuron in the hidden layer and the neuron in the output layer, b is the bias value of the output layer, δ o is the activation function.

[0050] In the converter circuit, the turn ratio of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is A; the turn ratio of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is B; the specific values of A and B are not limited in this embodiment. Since the turn ratios of the respective secondary windings and the primary winding of the coupled inductor T1 are different, different voltage gains can be obtained after selecting the corresponding topology of the converter by turning on and off the corresponding switching transistors, thereby enabling a high voltage conversion ratio.

[0051] When the converter is in a steady state, let the working period of the switching transistor be T S , and the duty cycle of the switching transistor S1 be D S ; the voltage gain of the converter circuit 11 is: where M1 is the voltage gain of the converter circuit 11, D S is the duty cycle of the switching transistor S1, n1 is the turn ratio A of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1, and m1 is the turn ratio B of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1.

[0052] During the operation of the converter, the converter can switch between multiple operating modes, specifically including the following three operating modes: Mode 1 (t0 - t1), Mode 2 (t1 - t2), and Mode 3 (t2 - t3).

[0053] The following will be described Figures 3 to 7 separately from each operating mode.

[0054] Mode 1 (t0 - t1): As Figure 4As shown, switch tube S1 conducts, first diode D1 conducts, and second diode D2 turns off; the input power supply V in supplies energy to the first inductor L and the magnetizing inductor L of coupled inductor T1 m ; first capacitor C1 discharges and supplies energy to the magnetizing inductor L of coupled inductor T1 through switch tube S1 m ; the current flowing through the first inductor L and the magnetizing inductor L of coupled inductor T1 m increases; second capacitor C2 is charged through the first secondary winding N2 and the second secondary winding N3 of coupled inductor T1, and second capacitor C2 stores energy; third capacitor C3 supplies energy to the DC load R; when switch tube S1 turns off, this mode ends.

[0055] Mode 1 ends and enters Mode 2 (t1 - t2): As Figure 5 shown, first diode D1 conducts, switch tube S1 turns off, second diode D2 turns off, first capacitor C1 continues to discharge, and second capacitor C2 continues to charge; third capacitor C3 supplies energy to the DC load R; the duration of this mode is short, and when first diode D1 turns off, this mode ends.

[0056] Mode 2 ends and enters Mode 3 (t2 - t3): As Figure 6 shown, second diode D2 conducts, switch tube S1 turns off, first diode D1 turns off, and the current flowing through the first secondary winding N2 of coupled inductor T1 is 0; the input power supply V in , first inductor L supply energy to first capacitor C1, and first capacitor C1 charges and stores energy; second capacitor C2 supplies energy to third capacitor C3 and DC load R through the second secondary winding N3 of coupled inductor T1, and third capacitor C3 charges and stores energy; when switch tube S1 conducts, Mode 3 ends and then enters Mode 1 of the next working cycle.

[0057] Based on the above embodiments, switch tube S1 is an N-channel MOSFET. During switch control, a switch duty ratio is delivered to the controlled end of the MOSFET. The switch duty ratio is a PWM pulse modulation signal with a preset duty ratio. Adjusting the duty ratio of the switch duty ratio can adjust the voltage gain of the topology. When the voltage between the gate and source of each MOSFET satisfies the conduction condition of the MOSFET, the MOSFET conducts; otherwise, the MOSFET turns off. Therefore, a corresponding PWM pulse modulation signal can be output to trigger the switch tube to conduct or turn off timely, thereby realizing the regulation of the voltage gain and obtaining a high voltage gain, that is, obtaining a high voltage conversion ratio.

[0058] The high-boost converter based on coupled inductance described in the above embodiments overcomes the disadvantages of traditional Boost converters, which are difficult to achieve high voltage conversion ratios and high conversion efficiencies. A coupled inductance is added to the converter circuit. By adjusting the turns ratio between the primary winding and each secondary winding of the first coupled inductance, a high voltage conversion ratio and high voltage output are obtained, avoiding the operation of the switching tube under extreme duty cycle conditions. The voltage stress that the switching tube needs to bear is relatively low, reducing the performance requirements for components such as the switching tube, and it can be better applied to the power system of new energy charging piles.

[0059] Furthermore, the technical solution of this embodiment combines the strategy of predicting the control law of the neural network fitting model, trains the neural network model, and determines the switching duty cycle through the trained neural network model combined with the sampling parameters, improving the dynamic performance of the converter circuit and reducing the disturbances caused by changes in the input voltage and load.

[0060] Another embodiment of the present application provides a charging pile, including the high-boost converter based on coupled inductance described in the above embodiments. The technical features and technical solutions not disclosed in this embodiment can refer to the content described in the above embodiments.

[0061] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0062] The above-described embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A high-boost converter based on a coupled inductor, characterized in that, It includes a converter circuit; The converter circuit includes: an input power supply V in , a switching transistor S1, a first inductor L, a first diode D1, a second diode D2, a coupled inductor T1, a first capacitor C1, a second capacitor C2, and a third capacitor C3. Among them, the coupled inductor T1 includes an exciting inductor L m , a primary winding N1, a first secondary winding N2, and a second secondary winding N3; The input power supply V in has its first terminal connected to the first terminal of the first inductor L; the second terminal of the first inductor L is connected to the second terminal of the first capacitor C1, the first terminal of the exciting inductor L m of the coupled inductor T1, the first terminal of the primary winding N1 of the coupled inductor T1, and the anode of the first diode D1; the second terminal of the exciting inductor L m of the coupled inductor T1 is connected to the second terminal of the primary winding N1 of the coupled inductor T1, the first terminal of the second secondary winding N3 of the coupled inductor T1, and the first terminal of the switching transistor S1; the cathode of the first diode D1 is connected to the second terminal of the first secondary winding N2 of the coupled inductor T1; the second terminal of the second secondary winding N3 of the coupled inductor T1 is connected to the second terminal of the second capacitor C2; the first terminal of the second capacitor C2 is connected to the first terminal of the first secondary winding N2 of the coupled inductor T1 and the anode of the second diode D2; the cathode of the second diode D2 is connected to the first terminal of the third capacitor C3 and forms a first load terminal; the second terminal of the input power supply V in is connected to the first terminal of the first capacitor C1, the second terminal of the switching transistor S1, and the second terminal of the third capacitor C3 and forms a second load terminal; The first load terminal and the second load terminal are used to connect to a DC load R; The third terminal of the switching transistor S1 is used to connect to the output terminal of the control module. The switching transistor S1 receives and conducts timely according to the switching control signal output by the control module, driving the converter circuit to work to achieve high voltage boost.

2. The high step-up converter based on a coupled inductor according to claim 1, wherein It also includes the control module, which includes an A / D conversion unit, a neural network controller, and a PWM unit connected in sequence; The A / D conversion unit is used to collect the output voltage signals of the first load terminal and the second load terminal, the first current signal flowing through the first inductor L, and the second current signal flowing through the excitation inductor L m , convert them into digital sampling signals, and transmit them to the neural network controller; The neural network controller receives the digital sampling signal, performs a weighted summation operation on the digital sampling signal through a trained neural network model, obtains the switching duty ratio for controlling the operation of the converter circuit, and inputs it to the PWM unit; The PWM unit receives and generates a switching control signal according to the switching duty ratio, and transmits it to the switching transistor S1 of the converter circuit to drive the converter circuit to work to achieve high voltage boost.

3. The high step-up converter based on a coupled inductor according to claim 2, wherein The training method of the neural network model is: Establish a converter discrete model according to the topological structure of the converter circuit; Obtain the output voltage state quantity of the converter circuit at the previous moment, the first current state quantity flowing through the first inductor L, and the second current state quantity flowing through the exciting inductor L m , and input them into the discrete model of the converter; Based on the output voltage state quantity, the first current state quantity, and the second current state quantity at the previous moment by the converter discrete model, combined with the corresponding objective function constraint conditions, solve to obtain the control laws corresponding to different operating points, and input them into the initial neural network model for training to obtain the neural network model.

4. The high step-up converter based on coupled inductors according to claim 3, characterized in that, The control laws corresponding to different operating points are obtained by solving the matrix equation of the converter discrete model. The matrix equation is: Among them, a is the current moment, a - 1 is the previous moment, and i L i(a) is the inductor current flowing through the first inductor L at moment a, and i Lm i(a) is the magnetizing inductor current flowing through the exciting inductor L m at moment a, V o V(a) is the output voltage of the converter circuit at moment a, and i L i(a - 1) is the first current state variable of the first inductor L flowing through at the previous moment, and i Lm i(a - 1) is the second current state variable of the exciting inductor L flowing through at the previous moment m at moment a, V o V(a - 1) is the output voltage state variable of the converter circuit at the previous moment, a ij is the matrix coefficient a 11 to a 33 , q ij where i = 1, 2, 3, a ij and j = 1, 2, 3, a ij are determined by the circuit parameters and control strategy of the converter circuit, b i is the matrix coefficient used to reflect the influence of input variables on the system state, and D(a - 1) is the disturbance variable at the previous moment, which is determined by the external interference of the converter circuit.

5. The high step-up converter based on coupled inductors according to claim 2, wherein The obtaining method of the switching duty ratio is: Through the hidden layer of the neural network model, using the corresponding activation function, perform a weighted summation operation on the digital sampling signal to obtain the hidden layer output value h n : where, w mn is the weight between the m-th neuron in the input layer and the n-th neuron in the hidden layer, M is the number of neurons in the input layer, b n is the bias value of the n-th neuron in the hidden layer, δ n is the activation function, and N is the number of neurons in the hidden layer; Through the output layer of the neural network model, using the corresponding activation function, perform a weighted summation operation on the output value h of the hidden layer n to obtain the switching duty cycle D o : where, w n is the weight between the n-th neuron in the hidden layer and the neuron in the output layer, b is the bias value of the output layer, and δ o is the activation function.

6. The high step-up converter based on coupled inductors according to claim 1, wherein, The turns ratio of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is A; The turns ratio of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1 is B.

7. The high step-up converter based on a coupled inductor according to claim 6, wherein The voltage gain of the converter circuit is: where M1 is the voltage gain of the converter circuit, D S is the duty cycle of the switching transistor S1, n1 is the turns ratio A of the first secondary winding N2 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1, and m1 is the turns ratio B of the second secondary winding N3 of the coupled inductor T1 to the primary winding N1 of the coupled inductor T1.

8. The high step-up converter based on coupled inductors according to claim 1, wherein The input power supply V in is a new energy power supply.

9. A charging pile, characterized in that, It includes a high voltage boost converter based on a coupled inductor according to any one of claims 1 to 8.

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