A Modular High-Power Charging Pile Control System, Method, Device and Medium

Abstract

The present invention relates to the technical field of charging control, and in particular to a modular high-power charging pile control system, method, device and medium. The control system includes: a plurality of control modules, and each control module includes: a mean low-pass filtering unit, a Butterworth filtering unit, a PI control unit, and a modulation unit. In the present invention, a mean low-pass filter and a Butterworth filter are connected in series. The series combination of the two forms wide-band noise suppression through complementary frequency domain characteristics. By connecting the mean low-pass filter in series, the anti-interference ability of the control system is improved, and at the same time, the dynamic performance of the control system is improved. Further, sliding mode control is used to perform voltage equalization control on the input side of the power unit, so as to achieve the goal of power balance of the output power of the power unit. Thereby, the problem that the influence of interference brought by the sampling signal on the control system in the prior art easily leads to ineffective balance control between internal modules of a modular high-power DC-DC charging pile is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of charging control, and particularly to a modular high-power charging pile control system, method, device and medium. Background Art

[0002] DC charging means that an electric vehicle directly obtains corresponding direct current from a DC charging system to charge a power battery. This charging mode can achieve rapid charging of the power battery. To improve usage safety and extend the equipment life, a strategy for balanced control between power units needs to be introduced. Traditional charging piles use hardware filtering or simple low-pass filtering to process sampling signals, and the delay introduced by them affects the system performance. For example, some solutions only use a filter amplification circuit to process sampling signals and do not perform additional processing in the control system. Or voltage sampling uses a hardware second-order RC low-pass filter (cutoff frequency 2 kHz) to filter out switching noise. The filtering link generates a -90° phase shift at 6 kHz (corresponding to the 6th harmonic), resulting in the inaccuracy of the harmonic compensation algorithm. The THD of the grid current rises from the designed <5% to 8.2%, which cannot meet the requirements of GB / T 18487.1-2015.

[0003] Therefore, there is an urgent need to design a control system for a modular high-power DC-DC charging pile to solve the problem that the interference brought by sampling signals affects the control system, resulting in ineffective balanced control between internal modules of the modular high-power DC-DC charging pile. Summary of the Invention

[0004] The present invention provides a modular high-power charging pile control system, method, device and medium, which are used to solve the problem that in the prior art, the interference brought by sampling signals affects the control system, easily resulting in ineffective balanced control between internal modules of the modular high-power DC-DC charging pile.

[0005] In view of this, in the first aspect of the present invention, a modular high-power charging pile control system is provided, and the system includes:

[0006] A plurality of control modules, each control module includes: a mean low-pass filtering unit, a Butterworth filtering unit, a PI control unit, and a modulation unit;

[0007] The mean low-pass filtering unit is used to weaken the high-frequency band energy of the voltage signal collected by the hardware circuit, and reduce the random noise variance of the voltage signal by smoothing the time-domain signal, and then input it to the Butterworth filtering unit;

[0008] The Butterworth filtering unit is used to filter out the high-frequency components of the voltage signal, and suppress the interference signal of the voltage signal by frequency-domain truncation, and then input it to the PI control unit;

[0009] The PI control unit is used to perform equal-voltage control on the voltage signal by using sliding mode control, and after modulation by the modulation unit, input it to the power unit of the charging pile.

[0010] Optionally, the performing equal-voltage control on the voltage signal by using sliding mode control includes: performing equal-voltage control on the voltage signal by using a sliding mode control model:

[0011] Wherein, the expression of the sliding mode control model is:

[0012] ;

[0013] In the formula, is the phase-shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, is the output voltage reference value, that is, the voltage signal output by the Butterworth filtering unit, is the output voltage, , , , are defined state variables, is the sliding mode control function, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

[0014] Optionally, the construction process of the sliding mode control model includes:

[0015] Establish the average switching equation of the power circuit of the charging pile in a switching period and add small-signal disturbances to construct a charging control model;

[0016] Analyze the working characteristics of the control system through the charging control model, and construct a sliding mode control model based on the working characteristics of the control system.

[0017] Optionally, the constructing a sliding mode control model based on the working characteristics of the control system includes:

[0018] Set the output voltage deviation parameter of the power unit for charging the charging pile;

[0019] Establish a state variable equation according to the output voltage deviation parameter, and design an equivalent control equation of the sliding mode switching hyperplane according to the state variable equation;

[0020] Substitute the state variable equation into the equivalent control equation to construct a sliding mode control model.

[0021] The second aspect of the present invention provides a modular high-power charging pile control method, which includes:

[0022] Weaken the high-frequency band energy of the voltage signal collected by the hardware circuit, and reduce the random noise variance of the voltage signal by smoothing the time-domain signal to obtain a first voltage signal;

[0023] Filter out the high-frequency components of the first voltage signal, and suppress the interference signal of the first voltage signal through frequency-domain truncation to obtain a second voltage signal;

[0024] Use sliding mode control to perform voltage equalization control on the second voltage signal, and input it to the power unit of the charging pile after signal modulation.

[0025] Optionally, the using sliding mode control to perform voltage equalization control on the second voltage signal includes: using a sliding mode control model to perform voltage equalization control on the second voltage signal:

[0026] Among them, the expression of the sliding mode control model is:

[0027] ;

[0028] In the formula, is the phase shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, is the output voltage reference value, that is, the voltage signal output by the Butterworth filter unit, is the output voltage, , , , are the defined state variables, is the sliding mode control function, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

[0029] Optionally, the construction process of the sliding mode control model includes:

[0030] Establish an average switching equation of the power circuit of the charging pile in a switching period and add small-signal disturbances to construct a charging control model;

[0031] Analyze the working characteristics of the control system through the charging control model, and construct a sliding mode control model based on the working characteristics of the control system.

[0032] Optionally, constructing a sliding mode control model based on the working characteristics of the control system includes:

[0033] Set the output voltage deviation parameter of the power unit for charging the charging pile;

[0034] Establish a state variable equation according to the output voltage deviation parameter, and design an equivalent control equation of the sliding mode switching hyperplane according to the state variable equation;

[0035] Substitute the state variable equation into the equivalent control equation to construct a sliding mode control model.

[0036] The third aspect of the present invention provides a modular high-power charging pile control device, which includes a processor and a memory:

[0037] The memory is used to store program code and transmit the program code to the processor;

[0038] The processor is used to execute the steps of the modular high-power charging pile control method as described in the second aspect above according to the instructions in the program code.

[0039] The fourth aspect of the present invention provides a computer-readable storage medium, which is used to store program code, and the program code is used to execute the modular high-power charging pile control method as described in the second aspect above.

[0040] It can be seen from the above technical solutions that the present invention has the following advantages:

[0041] The embodiment of the present invention provides a modular high-power charging pile control system. In the control module, on the one hand, a mean low-pass filter and a Butterworth filter are connected in series. The series combination of the two forms wide-band noise suppression through complementary frequency domain characteristics. The mean filter weakens the energy in the high-frequency band, and the Butterworth further filters out the residual high-frequency components. It can effectively suppress carrier harmonics and sensor quantization noise. The mean filter reduces the random noise variance by smoothing the time-domain signal, while the Butterworth suppresses deterministic interference through frequency-domain truncation, improving the robustness of the system to wide-spectrum interference. On the other hand, the sliding mode control is used to perform voltage equalization control on the voltage signal, and after being modulated by the modulation unit, it is input to the power unit of the charging pile, thereby achieving the goal of power unit output power balance, and thus solving the problem that the interference brought by the sampling signal affects the control system, which easily makes it impossible to effectively perform equalization control between the internal modules of the modular high-power DC-DC charging pile. This modular high-power charging pile control system of the present invention not only improves the suppression ability of wide-spectrum interference by combining the advantages of the mean low-pass filter and the Butterworth filter, but also realizes the voltage equalization control of the power unit through the sliding mode control strategy, further enhancing the stability and reliability of the system. In practical applications, the system can significantly improve the charging efficiency and safety of the charging pile, providing strong technical support for the rapid charging of electric vehicles and other devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0043] Figure 1 FIG. is a schematic structural diagram of a modular high-power charging pile control system provided by the embodiments of the present invention;

[0044] Figure 2 FIG. is a control block diagram of a PI control unit provided by the embodiments of the present invention;

[0045] Figure 3 FIG. is a schematic flow diagram of a modular high-power charging pile control process provided by the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] In order to make the object, features, and advantages of the present invention more obvious and understandable, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0047] Please refer to Figure 1 , a modular high-power charging pile control system provided in the embodiments of the present invention includes: a plurality of control modules, and each control module includes: a mean low-pass filtering unit, a Butterworth filtering unit, a PI control unit, and a modulation unit;

[0048] The mean low-pass filtering unit is used to weaken the high-frequency band energy of the voltage signal collected by the hardware circuit, and reduce the random noise variance of the voltage signal by smoothing the time-domain signal, and then input it to the Butterworth filtering unit;

[0049] The Butterworth filtering unit is used to filter out the high-frequency components of the voltage signal, and suppress the interference signal of the voltage signal by frequency-domain truncation, and then input it to the PI control unit;

[0050] The PI control unit is used to perform equal voltage control on the voltage signal by using sliding mode control, and input it to the power unit of the charging pile after being modulated by the modulation unit.

[0051] It should be noted that the modular high-power charging pile control system provided by the embodiments of the present invention is a control circuit for a modular high-power DC-DC (DC-DC is the abbreviation of "Direct Current-Direct Current", that is, direct current-direct current) charging pile, which controls the voltage balance between the power units of the charging pile and improves the filtering effect of the sampling signal.

[0052] As Figure 1 shown, each control module in the modular high-power charging pile control system of the present invention consists of a mean low-pass filter, a Butterworth filter, a PI control, and a modulation link. The voltage signal collected by the hardware circuit first passes through the mean low-pass filter and the Butterworth filter and then enters the PI control link. The output signal of the PI control link is transmitted to each power unit through signal modulation.

[0053] It can be understood that a mean low-pass filter and a Butterworth filter are connected in series in the control module. The two are connected in series and complement each other through frequency domain characteristics to form wide-band noise suppression. The mean filter weakens the energy in the high-frequency band, and the Butterworth further filters out the remaining high-frequency components. It can effectively suppress carrier harmonics and sensor quantization noise. The mean filter reduces the variance of random noise by smoothing the time-domain signal, while the Butterworth suppresses deterministic interference through frequency-domain truncation, improving the robustness of the system to wide-spectrum interference. In specific implementation, the controller uses FPGA parallel computing for mean filtering, and DSP realizes Butterworth recursion to achieve better performance through hardware acceleration.

[0054] Among them, the Butterworth filter is a commonly used low-pass filter. Its dynamic response speed is low and the high-frequency attenuation is slow. In order to improve the dynamic performance of the system, a mean low-pass filter is connected in series. The transfer function of the mean low-pass filter can be expressed as:

[0055] ;

[0056] Writing it in difference form gives:

[0057] ;

[0058] The transfer function of the Butterworth filter can be expressed in the following form:

[0059] ;

[0060] Writing it in difference form gives:

[0061] ;

[0062] It should be noted that the modulation strategy of the modulation unit in this embodiment can be PWM technology. This technology can not only effectively control the power output of the charging pile, but also optimize the power conversion efficiency and reduce harmonic distortion. The PWM modulation unit precisely adjusts the input voltage signal according to the preset algorithm and parameters to ensure the stable operation of the charging pile under various working conditions. At the same time, the application of the sliding mode control algorithm further improves the robustness and response speed of the system, enabling the charging pile to quickly adjust the voltage and maintain the stability of the output voltage in the face of power grid fluctuations or load changes, thus ensuring the charging efficiency and safety.

[0063] It should be noted that the present invention uses sliding mode control to perform voltage equalization control on the input side of the power unit, thereby achieving the goal of balancing the output power of the power unit. Specifically, the input voltage equalization control can balance the power output by establishing a small-signal model of the control system and analyzing it, and the sliding mode control is selected to achieve the voltage equalization control of the power unit. Among them, the sliding mode control is a non-linear control strategy. It designs a sliding surface in the state space so that the system state can still move stably along the sliding surface when affected by external disturbances or parameter changes. In the present invention, the sliding mode control is used to achieve the voltage equalization control of the power unit. By designing a suitable sliding surface and control law, the input voltage of the power unit can be kept stable, thereby achieving the goal of balancing the power output. This method has the advantages of strong robustness and fast response speed, and is suitable for the complex working environment of high-power charging piles.

[0064] In one embodiment, the PI control unit is used to: perform voltage equalization control on the voltage signal by using a sliding mode control model:

[0065] Among them, the expression of the sliding mode control model is:

[0066] ;

[0067] In the formula, is the phase shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

[0068] The construction process of the sliding mode control formula includes:

[0069] Establish the average switching equation of the power circuit of the charging pile in a switching period and add small-signal disturbances to construct a charging control model;

[0070] Analyze the working characteristics of the control system through the charging control model, and construct a sliding mode control model based on the working characteristics of the control system.

[0071] Among them, constructing a sliding mode control model based on the working characteristics of the control system includes:

[0072] Set the output voltage deviation parameter of the power unit for charging the charging pile;

[0073] Establish a state variable equation according to the output voltage deviation parameter, and design an equivalent control equation for the sliding mode switching hyperplane according to the state variable equation;

[0074] Substitute the state variable equation into the equivalent control equation to construct a sliding mode control model.

[0075] It should be noted that the principle explanation of the construction process of the sliding mode control formula is as follows:

[0076] The power imbalance of the modular high-power charging pile is mainly caused by the following factors: parameter deviations of inductors and transformers, parameter asymmetry caused by differences in the characteristics of switching devices, phase shift angle errors, load mutations, or input voltage disturbances. Assume that there are J power units, the inductor current is i Lj , the input-side support capacitor voltage U inj , the output-side filter capacitor voltage is U oj , the phase shift amount is D j . Combining the working principle of the circuit, establish the DC / DC system control model as follows:

[0077] ;

[0078] In the formula, is the inductor current, is the output-side filter capacitor voltage, input-side support capacitor voltage, is the inductor, is the output-side filter capacitor, is the input-side support capacitor, j is the power module serial number, and the symbols with j subscripts all represent the electrical parameters of the power module, is the input-side resistance, is the output-side resistance, isolation transformer voltage, is the switching period. is the phase shift amount , is the phase difference between the driving pulses of the two full-bridge switching tubes.

[0079] ;

[0080] ;

[0081] ;

[0082] In a cycle, the inductor currents can cancel each other out, and the corresponding average value is equal to zero, so it can be eliminated. Then, the average switching equation of the power circuit in a switching cycle can be obtained, and the switching equation can be represented by a matrix as follows:

[0083] ;

[0084] Adding small-signal perturbations to the stable operating point, in order to obtain the charging control model, linearization processing is required. The model expression after processing is as follows:

[0085] ;

[0086] ;

[0087] Among them, D j , U inj , U oj are used to represent the steady-state quantities of the system, , , , , s is the switching frequency, s is the complex variable in the Laplace transform, is the isolation transformer voltage. So there is the following relationship:

[0088] ;

[0089] The transmission power of the j-th module can be calculated, and the formula is as follows:

[0090] ;

[0091] In the formula, is the transmission power of the power unit.

[0092] If the charging pile consists of m power units with equal power for each power unit to ensure the normal operation of each power unit, then:

[0093] ;

[0094] In the formula, is the total output power.

[0095] For the output current sharing control of the charging pile, if the working efficiencies of each power unit are the same, then their input powers are also the same, and the input-side current relationship can be expressed as:

[0096] ;

[0097] Among them, represents the current of the input voltage-dividing capacitor, represents the input current of the power unit, the actual input current.

[0098] When the power unit is disturbed, assuming that its input voltage will increase accordingly, then the actual input current will decrease as the input voltage increases until the input current of the power unit is greater than the actual input current. At this time, the input capacitor is charged. The increase in the input voltage will bring about a positive feedback phenomenon, further promoting the above changes, and the system will not be able to work in an equilibrium state. Thus, it can be obtained that when the system is disturbed and deviates from the balance, it can be restored to a stable state through input voltage equalization control, while it is very difficult to ensure output current sharing control. Therefore, the power balance of each power unit of the system should be designed with the aim of input voltage equalization.

[0099] The power transmission of the charging pile is realized by high-frequency switching power devices. Its voltage equalization control needs to quickly respond to load changes and input disturbances. Using sliding mode control can obtain better dynamic response. Assume that the output voltage deviation is x1, the differential of the voltage deviation is x2, the integral of the voltage deviation is x3, and the second integral of the voltage deviation is x4. Establish the state variable equation:

[0100] ;

[0101] In the formula, is the output voltage reference value, is the output voltage.

[0102] Design the sliding mode switching hyperplane equation as:

[0103] ;

[0104] Equivalent control equation:

[0105] ;

[0106] Substitute the state variable equation into the equivalent control equation to get:

[0107] ;

[0108] Among them:

[0109] ;

[0110] In the formula, n is the turns ratio of the isolation transformer, L is the inductor, C o is the output capacitor, f s is the switching frequency, is the input voltage, is the output voltage reference value, and i o is the output current. Combining the above formulas, it can be generalized to the equivalent control quantities of any number of power modules. For example, the equivalent equation of the j-th power module is as follows:

[0111] ;

[0112] where L j is the inductor of the j-th power module, and C 2j is the output capacitor of the j-th power module.

[0113] When the sliding mode system based on equivalent control is in the S = 0, S’ = 0 mode, no switching occurs. At this time, the phase shift control quantity D = D eq ; When the phase shift control quantity D changes, S is forced to follow the reference sliding mode surface. Considering the discrete processing in practical applications and the switching frequency f s cannot be infinitely large, we get:

[0114] ;

[0115] where is the phase shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

[0116] The control block diagram can be obtained as shown in Figure 2 , where u o is the output voltage, and u ref is the output voltage command value.

[0117] An embodiment of the present invention provides a modular high-power charging pile control system. In the control module, on the one hand, a mean low-pass filter and a Butterworth filter are connected in series. The series combination of the two forms wide-band noise suppression through complementary frequency-domain characteristics. The mean filter weakens the energy in the high-frequency band, and the Butterworth further filters out the residual high-frequency components. It can effectively suppress carrier harmonics and sensor quantization noise. The mean filter reduces the random noise variance by smoothing the time-domain signal, while the Butterworth suppresses deterministic interference through frequency-domain truncation, improving the robustness of the system to wide-spectrum interference. On the other hand, sliding mode control is used to perform voltage equalization control on the voltage signal, and after being modulated by the modulation unit, it is input to the power unit of the charging pile, thereby achieving the goal of power output balance of the power unit, and solving the problem in the prior art that the interference brought by the sampling signal affects the control system, which easily makes it impossible to perform effective equalization control between the internal modules of the modular high-power DC-DC charging pile. This modular high-power charging pile control system of the present invention combines the advantages of the mean low-pass filter and the Butterworth filter, not only improving the suppression ability of wide-spectrum interference, but also realizing the voltage equalization control of the power unit through the sliding mode control strategy, further enhancing the stability and reliability of the system. In practical applications, this system can significantly improve the charging efficiency and safety of the charging pile, providing strong technical support for the fast charging of electric vehicles and other equipment.

[0118] The above is a modular high-power charging pile control system provided in the embodiment of the present invention. The following is a modular high-power charging pile control method provided in the embodiment of the present invention.

[0119] Please refer to Figure 3 , a modular high-power charging pile control method provided in the embodiment of the present invention includes:

[0120] Step 101: Weaken the energy in the high-frequency band of the voltage signal collected by the hardware circuit, and reduce the random noise variance of the voltage signal by smoothing the time-domain signal to obtain a first voltage signal.

[0121] Step 102: Filter out the high-frequency components of the first voltage signal, and suppress the interference signal of the first voltage signal through frequency-domain truncation to obtain a second voltage signal.

[0122] Step 103: Use sliding mode control to perform voltage equalization control on the second voltage signal, and input it to the power unit of the charging pile after signal modulation.

[0123] An embodiment of the present invention provides a modular high-power charging pile control method. First, the energy in the high-frequency band of the voltage signal collected by the hardware circuit is weakened, and the residual high-frequency components are further filtered out, which can effectively suppress carrier harmonics and sensor quantization noise. At the same time, the random noise variance of the voltage signal is reduced, and deterministic interference is suppressed by frequency-domain truncation, improving the robustness of the system to wide-spectrum interference. On the other hand, sliding mode control is used to perform voltage equalization control on the voltage signal and then input it to the power unit of the charging pile after modulation, so as to achieve the goal of power output balance of the power unit, thus solving the problem in the prior art that the interference brought by the sampling signal affects the control system, which easily makes it impossible to perform effective equalization control between the internal modules of the modular high-power DC-DC charging pile.

[0124] Further, an embodiment of the present invention also provides a modular high-power charging pile control device, which includes a processor and a memory:

[0125] The memory is used to store program codes and transmit the program codes to the processor;

[0126] The processor is used to execute the steps of the modular high-power charging pile control method as described in the above method embodiment according to the instructions in the program codes.

[0127] Further, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store program codes, and the program codes are used to execute the modular high-power charging pile control method as described in the above method embodiment.

[0128] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the above-described method can refer to the corresponding process in the foregoing system embodiment, and will not be elaborated herein.

[0129] In several embodiments provided by the present invention, it should be understood that the disclosed system and method can be implemented in other ways. For example, the system embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some interfaces, and the indirect coupling or communication connection of devices or units can be in electrical, mechanical or other forms.

[0130] The unit described as a separation component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0131] In addition, each functional unit in various embodiments of the present invention can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0132] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs and other various media that can store program codes.

[0133] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of various embodiments of the present invention.

Claims

1. A modular high-power charging pile control system, characterized in that: include: Several control modules, each of which includes: a mean low-pass filter unit, a Butterworth filter unit, a PI control unit and a modulation unit; The mean low-pass filter unit is used to weaken the high-frequency band energy of the voltage signal collected by the hardware circuit, and reduce the random noise variance of the voltage signal by smoothing the time domain signal before inputting it into the Butterworth filter unit; The Butterworth filter unit is used to filter out high-frequency components of the voltage signal, and suppress interference signals of the voltage signal by frequency domain truncation before inputting them into the PI control unit; The PI control unit is used to perform voltage balancing control on the voltage signal by using sliding mode control, and input the voltage signal to the power unit of the charging pile after being modulated by the modulation unit; The step of performing voltage balancing control on the voltage signal by using sliding mode control includes: performing voltage balancing control on the voltage signal by using a sliding mode control model: Wherein, the expression of the sliding mode control model is: ； In the formula, is the phase shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, is the output voltage reference value, that is, the voltage signal output by the Butterworth filter unit. is the output voltage, , , , is the state variable defined, is the synovial control function, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

2. The modular high-power charging pile control system according to claim 1 is characterized in that: The construction process of the sliding mode control model includes: Establish an average switching equation of the power circuit of the charging pile in a switching cycle and add small signal disturbances to build a charging control model; The operating characteristics of the control system are analyzed through the charging control model, and a sliding mode control model is constructed based on the operating characteristics of the control system.

3. The modular high-power charging pile control system according to claim 2 is characterized in that: The sliding mode control model is constructed based on the working characteristics of the control system, including: Set the output voltage deviation parameter of the power unit charged by the charging pile; Establishing a state variable equation according to the output voltage deviation parameter, and designing an equivalent control equation of a sliding membrane switching hyperplane according to the state variable equation; Substitute the state variable equation into the equivalent control equation to construct a sliding mode control model.

4. A modular high-power charging pile control method, characterized in that: include: Attenuating the high frequency band energy of the voltage signal collected by the hardware circuit, and reducing the random noise variance of the voltage signal by smoothing the time domain signal, to obtain a first voltage signal; filtering out high-frequency components of the first voltage signal, and suppressing interference signals of the first voltage signal by frequency domain truncation to obtain a second voltage signal; The second voltage signal is subjected to voltage balancing control by using sliding mode control, and is input into the power unit of the charging pile after signal modulation; The step of performing voltage balancing control on the second voltage signal by using sliding mode control includes: performing voltage balancing control on the second voltage signal by using a sliding mode control model: Wherein, the expression of the sliding mode control model is: ； In the formula, is the phase shift control quantity, is the equivalent control quantity, is the switching control quantity, is the switching control coefficient, is the output voltage reference value, that is, the voltage signal output by the Butterworth filter unit. is the output voltage, , , , is the state variable defined, is the synovial control function, represents the saturation function, is the gain coefficient, is the boundary layer of the sliding mode switching surface.

5. The modular high-power charging pile control method according to claim 4, characterized in that: The construction process of the sliding mode control model includes: Establish an average switching equation of the power circuit of the charging pile in a switching cycle and add small signal disturbances to build a charging control model; The operating characteristics of the control system are analyzed through the charging control model, and a sliding mode control model is constructed based on the operating characteristics of the control system.

6. The modular high-power charging pile control method according to claim 5, characterized in that: The sliding mode control model is constructed based on the working characteristics of the control system, including: Set the output voltage deviation parameter of the power unit charged by the charging pile; Establishing a state variable equation according to the output voltage deviation parameter, and designing an equivalent control equation of a sliding membrane switching hyperplane according to the state variable equation; Substitute the state variable equation into the equivalent control equation to construct a sliding mode control model.

7. A modular high-power charging pile control device, characterized in that: The device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the modular high-power charging pile control method described in any one of claims 4-6 according to the instructions in the program code.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program code, and the program code is used to execute the modular high-power charging pile control method described in any one of claims 4-6.

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