A charging station power allocation system, method, controller and charging station

Abstract

The present application relates to a charging station power allocation system, method, controller and charging station, and relates to the technical field of charging stations. The charging station power allocation system includes a sampling module and an allocation module. Among them, the sampling module is used to sample the first voltage value of the primary side of the transformer and the second voltage value of the secondary side of the transformer in the charging station. The allocation module is connected to the secondary side of the transformer and the sampling module, and is used to adjust the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value. The sampling module samples the first voltage value of the primary side of the transformer and the second voltage value of the secondary side of the transformer in the charging station, and the allocation module can analyze the power supply capacity of the current power grid through the first voltage value and the second voltage value. In this way, it is possible to achieve the effect of more accurately adjusting the power flow direction of the secondary side of the transformer according to the real-time power supply capacity of the power grid.

Description

Technical Field

[0001] The present application relates to the technical field of charging stations, and in particular to a charging station power allocation system, method, controller and charging station. Background Art

[0002] Charging stations are energy conversion devices that draw energy from the power grid to control the charging and discharging of electric vehicles. With the rapid development of the electric vehicle industry and the increasing number of electric vehicles, charging stations, as a key supporting facility, are also being built on a large scale. However, during the expansion of charging stations, the power supply system may be insufficient to meet the high-power charging demand, which can easily lead to overload of the power grid.

[0003] Currently, to avoid overloading the power grid, it is usually necessary to rationally allocate the power of the charging station. For example, by presetting the standard voltage of the charging station and monitoring the current voltage in real time, the power flow of the charging station can be adjusted by starting the energy storage inverter when the current voltage drops, thereby compensating for the dropped voltage. This can meet the charging needs of the charging station without overloading the power grid.

[0004] However, in the process of identifying the voltage drop depth and slope, there may be blind spots in the identification of different voltage drop speeds, and it is impossible to accurately identify frequently changing voltage drops, resulting in the inability to accurately allocate the power of the charging station. Summary of the Invention

[0005] The embodiments of the present application provide a charging station power allocation system for accurately allocating the power of the charging station to at least partially solve the above-mentioned technical problems.

[0006] To achieve the above objectives, according to a first aspect of the present application, a charging station power allocation system is provided, comprising:

[0007] a sampling module, configured to sample a first voltage value of a primary side of a transformer in a charging station and a second voltage value of a secondary side of the transformer;

[0008] The adjustment module is connected to the secondary side of the transformer and the sampling module, and is used to adjust the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value.

[0009] Optionally, the deployment module includes an energy storage reversing submodule and a control submodule;

[0010] The control submodule is connected to the sampling module and is configured to generate a commutation control signal according to the first voltage value and the second voltage value;

[0011] The energy storage commutation submodule is connected to the control submodule and the secondary side of the transformer, and is used to adjust the power flow direction of the secondary side of the transformer according to the commutation control signal.

[0012] Optionally, the energy storage and reversing submodule includes an AC / DC power converter and an energy storage battery;

[0013] The AC-DC power converter includes a first side connected to the secondary side of the transformer, a second side connected to the energy storage battery, and a control end connected to the control submodule, and is used to adjust the conduction direction according to the commutation control signal;

[0014] The energy storage battery is connected to the AC-DC power converter and is used for charging or discharging according to the conduction direction of the AC-DC power converter.

[0015] Optionally, the energy storage and commutation submodule further includes a DC power converter;

[0016] The DC power converter includes a first side connected to the energy storage battery and the AC-DC power converter and a second side connected to the charging load, and is used to convert power provided by the energy storage battery or the AC-DC power converter to supply power to the charging load.

[0017] Optionally, the sampling module further includes a current sampler connected in series to the secondary side of the transformer, for sampling the operating current signal of the secondary side of the transformer.

[0018] Optionally, the control submodule is used to obtain a voltage deviation value between the primary and secondary sides of the transformer based on the first voltage value and the second voltage value, and generate the commutation control signal based on the voltage deviation value and the operating current signal.

[0019] According to a second aspect of the present application, a charging station power allocation method is provided, which is applied to the above-mentioned charging station power allocation system, including:

[0020] Acquire, by the sampling module, a first voltage value of a primary side of a transformer in the charging station and a second voltage value of a secondary side of the transformer;

[0021] The power flow direction of the secondary side of the transformer is adjusted according to the first voltage value and the second voltage value by the adjustment module.

[0022] Optionally, the adjustment module includes an AC / DC power converter, and adjusting the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value by the adjustment module includes:

[0023] Obtaining a voltage deviation value between the primary side and the secondary side of the transformer according to the first voltage value and the second voltage value;

[0024] The conduction direction of the AC-DC power converter is adjusted according to the voltage deviation value, so as to adjust the power flow direction of the secondary side of the transformer.

[0025] Optionally, adjusting the conduction direction of the AC-DC power converter according to the voltage deviation value includes:

[0026] Sampling the current on the secondary side of the transformer to obtain an operating current signal;

[0027] A commutation control signal is generated according to the voltage deviation value and the operating current signal, so that the AC-DC power converter adjusts the conduction direction according to the commutation control signal.

[0028] Optionally, the commutation control signal includes a first adjustment signal and a second adjustment signal; the adjustment module includes an energy storage battery; and generating the commutation control signal according to the voltage deviation value and the operating current signal includes:

[0029] When the voltage deviation value is greater than or equal to zero, obtaining a charging demand current of the energy storage battery, and generating a first adjustment signal according to the charging demand current and the operating current signal to control the AC-DC power converter to conduct in a first direction;

[0030] When the voltage deviation value is less than zero, obtaining the discharge demand current of the energy storage battery, generating a commutation adjustment value according to the voltage deviation value, and generating a second adjustment signal according to the commutation adjustment value, the discharge demand current, and the operating current signal to control the AC-DC power converter to conduct in a second direction;

[0031] The first direction is a direction from a first side to a second side of the AC-DC power converter, and the second direction is a direction from the second side to the first side of the AC-DC power converter.

[0032] Optionally, generating a commutation adjustment value according to the voltage deviation value includes:

[0033] Performing proportional-integral processing on the voltage deviation value to obtain a demand adjustment amount;

[0034] determining a limiting range according to the discharge demand current;

[0035] The demand adjustment amount is limited according to the limiting range to obtain the switching adjustment amount.

[0036] Optionally, generating a second adjustment signal according to the commutation adjustment amount, the discharge demand current, and the operating current signal includes:

[0037] generating a demand control signal according to the commutation adjustment amount and the discharge demand current, and performing phase-locking processing on the demand control signal so that the phase of the demand control signal is consistent with the phase of the primary voltage of the transformer;

[0038] Calculating a current difference according to the demand control signal and the operating current signal;

[0039] Proportional integration processing is performed on the current difference to obtain the second adjustment signal.

[0040] Optionally, the method further includes:

[0041] The remaining power of the energy storage battery is obtained, and if the remaining power is lower than a preset value, an alarm message is output.

[0042] According to a third aspect of the present application, a controller is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0043] According to a fourth aspect of the present application, a charging station includes the above-mentioned charging station power allocation system.

[0044] To sum up, in the charging station power allocation system of the embodiment of the present application, the sampling module samples the first voltage value of the primary side of the transformer and the second voltage value of the secondary side of the transformer in the charging station. The allocation module can analyze the current power supply capacity of the power grid through the first voltage value and the second voltage value, and can achieve the effect of more accurately adjusting the power flow direction of the secondary side of the transformer according to the real-time power supply capacity of the power grid.

[0045] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0047] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0048] Figure 1is a schematic diagram of a charging station power allocation system provided in an exemplary embodiment of the present disclosure;

[0049] Figure 2 is a schematic diagram of an application scenario of a charging station power allocation system provided in an exemplary embodiment of the present disclosure;

[0050] Figure 3 is a circuit connection diagram of a charging station power allocation system provided in an exemplary embodiment of the present disclosure;

[0051] Figure 4 is a schematic diagram of the secondary side power flow of a transformer provided in an exemplary embodiment of the present disclosure;

[0052] Figure 5 is a flow chart of a charging station power allocation method provided in an exemplary embodiment of the present disclosure;

[0053] Figure 6 2 is a schematic diagram of a control scenario of a charging station power allocation method provided in an exemplary embodiment of the present disclosure.

[0054] Explanation of the accompanying drawings: 1. Sampling module; 2. Adjustment module; 21. Energy storage commutation submodule; 211. AC / DC power converter; 212. Energy storage battery; 213. DC power converter; 22. Control submodule. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0056] According to the first aspect of this application, referring to Figures 1 to 4 The present disclosure provides a charging station power allocation system, comprising a sampling module 1 and an allocation module 2. Sampling module 1 is configured to sample a first voltage value on the primary side of a transformer in the charging station and a second voltage value on the secondary side of the transformer. Allocation module 2 is connected to the secondary side of the transformer and sampling module 1 and is configured to adjust the power flow on the secondary side of the transformer based on the first and second voltage values.

[0057] When the grid's supply capacity is insufficient, the grid's equivalent impedance (including line impedance and transformer impedance) is relatively large, resulting in a significant voltage drop when current flows through it. To maintain the stability of the transformer's secondary voltage, the grid raises the transformer's primary voltage by adjusting the transformer's connectors, for example, to compensate for the losses caused by the voltage drop. Therefore, when the grid's supply capacity is insufficient and the transformer's primary voltage needs to be increased to meet load demand, the transformer's primary voltage will be greater than its secondary voltage. When the grid's supply capacity is sufficient, the grid's equivalent impedance is relatively low, and current does not cause a significant voltage drop. The grid not only does not need to increase the transformer's primary voltage to compensate for losses, but can also optimize power transmission efficiency by reducing the primary voltage. Therefore, when the grid's supply capacity is sufficient and there is no need to increase or reduce the transformer's primary voltage, the transformer's primary voltage will be less than or equal to its secondary voltage.

[0058] Therefore, when the first voltage value is greater than the second voltage value, it indicates that the power grid's power supply capacity is weak. When the first voltage value is less than or equal to the second voltage value, it indicates that the power grid's power supply capacity is strong. In this way, by comparing the first and second voltage values, the power grid's power supply capacity can be reflected, allowing for more accurate adjustment of the power flow on the secondary side of the transformer.

[0059] Combine Figure 2 For example, the primary side of the transformer in a charging station is connected to the grid, and the secondary side of the transformer is connected to the dispatch module 2 to provide energy to the charging load. For example, in a 4S dealership, to meet customer charging needs, multiple charging stations are typically required to charge multiple charging loads, such as vehicles. Each charging station converts energy using transformer T1. The primary side of each transformer T1 is connected to the grid, and its secondary side is regulated by the power dispatch system of the respective substation to supply power to the charging load, thus distributing grid power.

[0060] In the above embodiment, the sampling module 1 samples the first voltage value of the primary side and the second voltage value of the secondary side of the transformer in the charging station, and the allocation module 2 can analyze the power supply capacity of the current power grid through the first voltage value and the second voltage value, and can achieve the effect of more accurately adjusting the power flow direction of the secondary side of the transformer according to the real-time power supply capacity of the power grid.

[0061] Reference Figure 3 In some embodiments, the allocation module 2 includes an energy storage commutation submodule 21 and a control submodule 22. The control submodule 22 is connected to the sampling module 1 and is configured to generate a commutation control signal based on the first voltage value and the second voltage value. The energy storage commutation submodule 21 is connected to the control submodule 22 and the secondary side of the transformer and is configured to adjust the power flow on the secondary side of the transformer based on the commutation control signal.

[0062] In the above embodiment, the control submodule 22 is connected to the sampling module 1, and can obtain the first voltage value of the primary side and the second voltage value of the secondary side of the transformer, and generate a commutation control signal for quantifying the power supply capacity of the power grid based on the first voltage value and the second voltage value, so that the energy storage commutation submodule 21 can make corresponding adjustments to the power flow direction of the secondary side of the transformer after receiving the commutation control signal issued by the control submodule 22.

[0063] In some embodiments, the energy storage and commutation submodule 21 includes an AC / DC power converter 211 and an energy storage battery 212. The AC / DC power converter 211 includes a first side connected to the secondary side of the transformer, a second side connected to the energy storage battery 212, and a control terminal connected to the control submodule 22, configured to adjust the conduction direction based on a commutation control signal. The energy storage battery 212 is connected to the AC / DC power converter 211 and configured to charge or discharge based on the conduction direction of the AC / DC power converter 211.

[0064] As an example, the AC-DC power converter 211 is a bidirectional energy conversion device that can realize bidirectional conversion between AC and DC. The secondary side of the transformer is also connected to other loads. Continuing with the example of a vehicle 4S store, other loads can be office electricity or warehouse electricity, etc. Figure 4 In (a), when the first voltage value is less than or equal to the second voltage value, the grid's power supply capacity is strong. At this time, the transformer's secondary side not only supplies AC power to other loads but also transmits the AC power to AC-DC power converter 211. AC-DC power converter 211 operates in rectification mode, converting the AC power on the transformer's secondary side into DC power to power the charging loads and charging energy storage battery 212, thereby storing excess power on the transformer's secondary side. At this time, the transformer's secondary side power flows from the transformer's secondary side to the other loads and AC-DC power converter 211, and then is transmitted through AC-DC power converter 211 to energy storage battery 212 and the charging loads.

[0065] Combine Figure 4 In (b), when the first voltage value is greater than the second voltage value, the grid's power supply capacity is weak. AC / DC converter 211 is in inverter mode, converting the DC power discharged from energy storage battery 212 to power the charging load. Simultaneously, AC / DC converter 211 inverts the DC power output from energy storage battery 212 into AC power, which is then fed to the secondary side of the transformer to power other loads. At this point, the power on the transformer's secondary side flows from energy storage battery 212 to the charging load. Meanwhile, the output of energy storage battery 212 is transmitted through AC / DC converter 211 to the transformer's secondary side, thereby powering other loads connected to the transformer's secondary side.

[0066] In this way, when the power supply capacity of the grid is relatively strong, the secondary side of the transformer provides energy to the charging load and other loads and charges the energy storage battery 212, while when the power supply capacity of the grid is relatively weak, the energy storage battery 212 provides energy to the charging load and other loads.

[0067] Reference Figure 3 In some embodiments, the energy storage and reversing submodule 21 further includes a DC power converter 213. The DC power converter 213 includes a first side connected to the energy storage battery 212 and the AC / DC power converter 211, and a second side connected to the charging load. The DC power converter 213 is configured to convert power provided by the energy storage battery 212 or the AC / DC power converter 211 to supply power to the charging load.

[0068] In the above embodiment, when the first voltage value is less than or equal to the second voltage value, the DC power converter 213 converts the power provided by the AC / DC power converter 211 to supply power to the charging load. When the first voltage value is greater than the second voltage value, the DC power converter 213 converts the power from the energy storage battery 212 to supply power to the charging load. The DC power converter 213 ensures the stability of the power supply to the charging load, allowing the charging load to be charged at a stable voltage.

[0069] In some embodiments, the sampling module 1 further includes a current sampler connected in series to the secondary side of the transformer for sampling the operating current signal of the secondary side of the transformer. The control submodule 22 is configured to obtain a voltage deviation between the primary and secondary sides of the transformer based on the first voltage value and the second voltage value, and to generate a commutation control signal based on the voltage deviation and the operating current signal.

[0070] As an example, the current sampler may be a current transformer, which may convert a large current on the secondary side of a transformer into a small current signal in proportion for measurement.

[0071] Reference Figure 5 According to the second aspect of the present application, a charging station power allocation method is provided, which is applied to the above-mentioned charging station power allocation system, including steps S100 to S200, which are described in detail below.

[0072] Step S100: obtaining a first voltage value of a primary side of a transformer and a second voltage value of a secondary side of the transformer in a charging station through a sampling module 1.

[0073] Step S200: adjusting the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value by the adjustment module 2.

[0074] In the above embodiment, the sampling module 1 samples the first voltage value of the primary side and the second voltage value of the secondary side of the transformer in the charging station, and the allocation module 2 can analyze the power supply capacity of the current power grid through the first voltage value and the second voltage value, and can achieve the effect of more accurately adjusting the power flow direction of the secondary side of the transformer according to the real-time power supply capacity of the power grid.

[0075] In some embodiments, the adjustment module 2 includes an AC / DC power converter 211 , and step S200 may include steps S210 to S220 , which are described in detail below.

[0076] Step S210: Obtain a voltage deviation value between the primary side and the secondary side of the transformer according to the first voltage value and the second voltage value.

[0077] As an example, the voltage deviation value can be the difference between the second voltage value and the first voltage value. When the voltage deviation value is greater than or equal to zero, the first voltage value is less than or equal to the second voltage value, indicating that the power supply capacity of the power grid is relatively strong. When the voltage deviation value is less than zero, the first voltage value is greater than the second voltage value, indicating that the power supply capacity of the power grid is relatively weak.

[0078] Step S220 : adjusting the conduction direction of the AC-DC power converter 211 according to the voltage deviation value, so as to adjust the power flow direction of the secondary side of the transformer.

[0079] As an example, the AC / DC power converter 211 can achieve bidirectional conversion between AC and DC, and its conduction direction determines the direction of power transmission. By controlling its conduction direction through the voltage deviation value, the flow direction of the secondary side power of the transformer can be flexibly controlled.

[0080] As an example, step S220 may include steps S221 and S222, which are described in detail below.

[0081] Step S221: sampling the current on the secondary side of the transformer to obtain an operating current signal.

[0082] As an example, the current of the secondary side of the transformer during actual operation is measured in real time by a current sampler to obtain an operating current signal, which reflects the operating state of the secondary side of the transformer.

[0083] Step S222 : generating a commutation control signal according to the voltage deviation value and the operating current signal, so that the AC-DC power converter 211 adjusts the conduction direction according to the commutation control signal.

[0084] As an example, the AC-DC power converter 211 may be a full-bridge rectifier circuit, which includes several power switching devices. The commutation control signal may be a pulse-width modulation (PWM) signal. The commutation control signal may be multiple, with each commutation control signal used to control a power switching device in the AC-DC power converter 211. In the AC-DC power converter 211, by adjusting the duty cycle of the commutation control signal, the on-time and off-time of the power switching devices in the AC-DC power converter 211 can be changed, thereby controlling the energization time of the primary side of the transformer within the AC-DC power converter 211. For example, when the duty cycle of the commutation control signal increases, the on-time of the power switching devices in the AC-DC power converter 211 is prolonged, increasing the energy stored in the primary side of the transformer within the AC-DC power converter 211 and the energy transferred to its secondary side, thereby increasing the output voltage of the AC-DC power converter 211. Conversely, when the duty cycle decreases, the output voltage of the AC-DC power converter 211 decreases. In addition, by adjusting the phase of the commutation control signal, the conduction timing of each power switch device in the AC-DC power converter 211 is controlled so that the power switch devices in the AC-DC power converter 211 are turned on or off in different combinations, thereby realizing the control of the conduction direction of the AC-DC power converter 211.

[0085] In this way, the conduction direction of the AC-DC power converter 211 can be determined by the voltage deviation value, thereby determining the phase of the commutation control signal. The operating current signal, as the feedback quantity of the AC-DC power converter 211, can determine the signal amplitude required to be output by the AC-DC power converter 211, thereby determining the duty cycle of the commutation control signal. Therefore, based on the voltage deviation value and the operating current signal, a commutation control signal can be obtained to adjust the conduction direction and output voltage amplitude of the AC-DC power converter 211.

[0086] In some embodiments, the commutation control signal includes a first adjustment signal and a second adjustment signal, and the adjustment module 2 includes an energy storage battery 212. Step S222 may include steps S2221 and S2222, which are described in detail below.

[0087] Step S2221: When the voltage deviation value is greater than or equal to zero, the charging demand current of the energy storage battery 212 is obtained, and a first adjustment signal is generated according to the charging demand current and the operating current signal to control the AC-DC power converter 211 to conduct in a first direction.

[0088] For example, when the voltage deviation value is greater than or equal to zero, it indicates that the power grid's power supply capacity is relatively strong, and the grid is providing energy to charge the energy storage battery 212. Therefore, at this time, the charging demand current of the energy storage battery 212 is obtained. The charging demand current serves as the ideal output value that the AC-DC power converter 211 is expected to achieve, and the operating current signal serves as the actual measured value. By performing a proportional integral operation on the charging demand current and the operating current signal, a first adjustment signal can be obtained. The first adjustment signal is used to control the AC-DC power converter 211 to conduct in a first direction from the first side to the second side of the AC-DC power converter 211, thereby charging the energy storage battery 212.

[0089] Step S2222: When the voltage deviation value is less than zero, the discharge demand current of the energy storage battery 212 is obtained, a commutation adjustment value is generated according to the voltage deviation value, and a second adjustment signal is generated according to the commutation adjustment value, the discharge demand current and the operating current signal to control the AC-DC power converter 211 to conduct in the second direction.

[0090] As an example, when the voltage deviation value is less than zero, it indicates that the power supply capacity of the grid is relatively weak and the grid cannot provide enough energy. The energy storage battery 212 needs to provide part of the energy, so the discharge demand current of the energy storage battery 212 needs to be obtained.

[0091] The first direction is from the first side to the second side of the AC-DC power converter 211, and the second direction is from the second side to the first side of the AC-DC power converter 211. The charging demand current and the discharging demand current can be obtained by the charge and discharge curve of the energy storage battery 212. The charge and discharge curves of different types of energy storage batteries 212 may be different. Figure 6 , Ia represents the discharge demand current, Ib represents the charging demand current; U1 represents the first voltage value, U2 represents the second voltage value, and I1 represents the operating current signal.

[0092] In some embodiments, generating a commutation adjustment value according to a voltage deviation value may include steps S201 to S203 , which are described in detail below.

[0093] Step S201: performing proportional integral processing on the voltage deviation value to obtain a demand adjustment amount.

[0094] For example, proportional-integral processing is a commonly used control algorithm that can be executed using a PI (Proportional-Integral) controller. The PI controller performs a proportional operation on the voltage deviation to amplify or reduce the voltage deviation, while also performing an integral operation to accumulate the change in the voltage deviation over time. This results in a demand adjustment, reflecting the required adjustment based on the current voltage deviation. The demand adjustment and the voltage deviation have the same sign. When the voltage deviation is greater than or equal to zero, the demand adjustment is also greater than or equal to zero; when the voltage deviation is less than zero, the demand adjustment is also less than zero.

[0095] Step S202: determining a limit range according to the required discharge current.

[0096] Step S203: limiting the demand adjustment amount according to the limiting range to obtain the switching adjustment amount.

[0097] As an example, the limiting range can be expressed as [-2×Ia, 0]. When the demand adjustment value is less than -2×Ia, the commutation adjustment value is -2×Ia. When the demand adjustment value is greater than or equal to -2×Ia and less than 0, the demand adjustment value is used as the commutation adjustment value. When the demand adjustment value is greater than 0, the commutation adjustment value is 0. If the voltage deviation value is greater than zero, the commutation adjustment value is not output, and the first adjustment signal is directly generated based on the charging demand current and the operating current signal.

[0098] In the above embodiment, the commutation adjustment amount is obtained by limiting the demand adjustment amount, thereby preventing the output of the AC-DC power converter 211 from exceeding the rated voltage of the energy storage battery 212 and causing damage to the energy storage battery 212.

[0099] In some embodiments, generating the second adjustment signal according to the commutation adjustment amount, the discharge demand current, and the operating current signal may include steps S204 to S206, which are described in detail below.

[0100] Step S204: generating a demand control signal according to the commutation adjustment amount and the discharge demand current, and performing phase-locking processing on the demand control signal so that the phase of the demand control signal is consistent with the phase of the primary voltage of the transformer.

[0101] Step S205: Calculate the current difference according to the demand control signal and the operating current signal.

[0102] Step S206: performing proportional integration processing on the current difference to obtain a second adjustment signal.

[0103] In some embodiments, the charging station power allocation method further includes obtaining the remaining power of the energy storage battery 212 , and outputting an alarm message if the remaining power is lower than a preset value.

[0104] This disclosure exemplarily describes the working process of the charging station power allocation method:

[0105] First, a commutation control signal with a different duty cycle and phase is generated based on the voltage deviation value and the operating current signal. The commutation control signal can directly control the conduction direction and output amplitude of the AC-DC power converter 211, eliminating the need for additional switch control and the issue of switch control delay. Then, by controlling the conduction direction and output amplitude of the AC-DC power converter 211, the secondary power flow direction of the transformer is adjusted. Furthermore, the voltage deviation value is obtained by comparing the first voltage value with the second voltage value, which is relatively simple and can achieve zero-time switching. It is not affected by the speed of the transformer voltage drop and there is no recognition blind spot, thereby achieving more accurate and rapid adjustment of the secondary power of the transformer.

[0106] According to a third aspect of the present application, a controller is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0107] According to a fourth aspect of the present application, a charging station includes the above-mentioned charging station power allocation system.

[0108] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0109] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0110] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0111] The above are merely preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A charging station power allocation system, characterized in that: include: a sampling module, configured to sample a first voltage value of a primary side of a transformer in a charging station and a second voltage value of a secondary side of the transformer; The adjustment module is connected to the secondary side of the transformer and the sampling module, and is used to adjust the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value.

2. The charging station power allocation system according to claim 1, characterized in that: The deployment module includes an energy storage reversing submodule and a control submodule; The control submodule is connected to the sampling module and is configured to generate a commutation control signal according to the first voltage value and the second voltage value; The energy storage commutation submodule is connected to the control submodule and the secondary side of the transformer, and is used to adjust the power flow direction of the secondary side of the transformer according to the commutation control signal.

3. The charging station power allocation system according to claim 2, characterized in that: The energy storage commutation submodule includes an AC / DC power converter and an energy storage battery; The AC-DC power converter includes a first side connected to the secondary side of the transformer, a second side connected to the energy storage battery, and a control end connected to the control submodule, and is used to adjust the conduction direction according to the commutation control signal; The energy storage battery is connected to the AC-DC power converter and is used for charging or discharging according to the conduction direction of the AC-DC power converter.

4. The charging station power allocation system according to claim 3, characterized in that: The energy storage commutation submodule also includes a DC power converter; The DC power converter includes a first side connected to the energy storage battery and the AC-DC power converter and a second side connected to a charging load, and is used to convert power provided by the energy storage battery or the AC-DC power converter to supply power to the charging load.

5. The charging station power allocation system according to claim 2, characterized in that: The sampling module further includes a current sampler connected in series to the secondary side of the transformer, for sampling the operating current signal of the secondary side of the transformer.

6. The charging station power allocation system according to claim 5, characterized in that: The control submodule is used to obtain a voltage deviation value between the primary side of the transformer and the secondary side of the transformer according to the first voltage value and the second voltage value, and generate the commutation control signal according to the voltage deviation value and the operating current signal.

7. A charging station power allocation method, characterized in that: The charging station power allocation system according to any one of claims 1 to 6 comprises: Acquire, by the sampling module, a first voltage value of a primary side of a transformer in the charging station and a second voltage value of a secondary side of the transformer; The power flow direction of the secondary side of the transformer is adjusted according to the first voltage value and the second voltage value by the adjustment module.

8. The charging station power allocation method according to claim 7, characterized in that: The adjustment module includes an AC / DC power converter, and adjusting the power flow direction of the secondary side of the transformer according to the first voltage value and the second voltage value by the adjustment module includes: Obtaining a voltage deviation value between the primary side and the secondary side of the transformer according to the first voltage value and the second voltage value; The conduction direction of the AC-DC power converter is adjusted according to the voltage deviation value, so as to adjust the power flow direction of the secondary side of the transformer.

9. The charging station power allocation method according to claim 8, characterized in that: The step of adjusting the conduction direction of the AC-DC power converter according to the voltage deviation value includes: Sampling the current on the secondary side of the transformer to obtain an operating current signal; A commutation control signal is generated according to the voltage deviation value and the operating current signal, so that the AC-DC power converter adjusts the conduction direction according to the commutation control signal.

10. The charging station power allocation method according to claim 9, characterized in that: The commutation control signal includes a first adjustment signal and a second adjustment signal; the adjustment module includes an energy storage battery; and the generating of the commutation control signal according to the voltage deviation value and the operating current signal includes: When the voltage deviation value is greater than or equal to zero, obtaining a charging demand current of the energy storage battery, and generating a first adjustment signal according to the charging demand current and the operating current signal to control the AC-DC power converter to conduct in a first direction; When the voltage deviation value is less than zero, obtaining the discharge demand current of the energy storage battery, generating a commutation adjustment value according to the voltage deviation value, and generating a second adjustment signal according to the commutation adjustment value, the discharge demand current, and the operating current signal to control the AC-DC power converter to conduct in a second direction; The first direction is a direction from a first side to a second side of the AC-DC power converter, and the second direction is a direction from the second side to the first side of the AC-DC power converter.

11. The charging station power allocation method according to claim 10, characterized in that: Generating a commutation adjustment amount according to the voltage deviation value includes: Performing proportional-integral processing on the voltage deviation value to obtain a demand adjustment amount; determining a limiting range according to the discharge demand current; The demand adjustment amount is limited according to the limiting range to obtain the switching adjustment amount.

12. The charging station power allocation method according to claim 10, characterized in that: Generating a second adjustment signal according to the commutation adjustment amount, the discharge demand current, and the operating current signal includes: generating a demand control signal according to the commutation adjustment amount and the discharge demand current, and performing phase-locking processing on the demand control signal so that the phase of the demand control signal is consistent with the phase of the primary voltage of the transformer; Calculating a current difference according to the demand control signal and the operating current signal; Proportional integration processing is performed on the current difference to obtain the second adjustment signal.

13. The charging station power allocation method according to claim 10, characterized in that: The method further comprises: The remaining power of the energy storage battery is obtained, and if the remaining power is lower than a preset value, an alarm message is output.

14. A controller having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 7 to 13 are implemented.

15. A charging station, characterized in that: It includes the charging station power allocation system as described in any one of claims 1 to 6.

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