Charging power control method of charging pile, controller and optical storage and charging system

Abstract

The invention discloses a charging power control method of a charging pile, a controller and an optical storage and charging system, and relates to the technical field of charging control, the optical storage and charging system comprises an intelligent distribution box, an inverter and a plurality of loads, the plurality of loads comprise charging piles, the DC side of the inverter is connected with a DC power supply, and the DC power supply is connected with the controller. An alternating-current side grid-connected port of the inverter is connected with a power grid through a first circuit breaker in the intelligent distribution box and a home-entry master switch outside the intelligent distribution box in sequence, and an alternating-current side load port of the inverter is connected with all or part of loads through a second circuit breaker in the intelligent distribution box. The method comprises the steps that the operation condition of the optical storage and charging system is obtained, the operation condition represents the states of an inverter and a second circuit breaker and the electrical load change of the optical storage and charging system, and the power limit value of a charging pile is determined according to the operation condition and the access position of the charging pile in the optical storage and charging system; therefore, the power control instruction is sent to the charging pile according to the power limit value, and flexible control over the charging power is achieved.

Description

Technical Field

[0001] This application relates to the field of charging control technology, and in particular to a charging power control method, controller and photovoltaic energy storage charging system for a charging pile. Background Technology

[0002] With the energy transition and the development of renewable energy technologies, new energy vehicles are becoming increasingly popular, and the number of home charging stations for charging new energy vehicles is also increasing.

[0003] Home charging stations, as high-power special loads in the home, directly affect the safety of the entire household circuit. If the charging station charges at a fixed maximum power, it can easily cause the power distribution system to overload and trip during normal household electricity use. Summary of the Invention

[0004] In view of the above problems, this application provides a charging power control method, controller, and photovoltaic-storage-charging system for charging piles, solving the problem that charging at a fixed maximum power easily leads to overload tripping of the power distribution system. The specific solution is as follows: The first aspect of this application provides a charging power control method for a charging pile, including: The system obtains the operating status of a photovoltaic-storage-charging system, which includes a smart distribution box, an inverter, and multiple loads, including charging piles. The DC side of the inverter is connected to a DC power supply, and the AC side grid connection port of the inverter is connected to the power grid sequentially through a first circuit breaker in the smart distribution box and a main switch outside the smart distribution box. The AC side load port of the inverter is connected to all or part of the loads through a second circuit breaker in the smart distribution box. The operating status indicates the state of the inverter and the second circuit breaker, as well as the changes in the power load of the photovoltaic-storage-charging system. Based on the operating conditions and the access location of the charging pile in the photovoltaic energy storage and charging system, the power limit of the charging pile is determined. A power control command is sent to the charging pile according to the power limit.

[0005] In one possible implementation, determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic energy storage and charging system includes: When the inverter is online and no high-power equipment is started in the operating condition, the current of the power extraction circuit where the charging pile is located is obtained according to the access location of the charging pile in the photovoltaic energy storage charging system. The high-power equipment includes: electrical equipment with a starting instantaneous power greater than a first threshold and energy storage battery with a starting charging instantaneous power greater than a second threshold. Obtain the status of the charging pile; The power limit is determined based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, as well as the status of the charging pile.

[0006] In one possible implementation, obtaining the current of the power extraction circuit where the charging pile is located, based on the access location of the charging pile in the photovoltaic energy storage and charging system, includes: When the charging pile is connected to the second circuit breaker, the vector sum of the load current and the photovoltaic storage current in the phase sequence where the charging pile is located is determined as the current of the power extraction circuit where the charging pile is located. When the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, the current of the power supply circuit where the charging pile is located is determined based on the total active power of the household, the phase sequence voltage of the charging pile, and the power factor.

[0007] In one possible implementation, determining the power limit based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, and the state of the charging pile, includes: When the charging pile is not activated, if the current in the power supply circuit of the charging pile is less than the difference between the current threshold of the power supply circuit and the first margin current, then after the charging pile is activated, the product of the remaining available safe current in the power supply circuit of the charging pile and the phase sequence voltage of the charging pile is determined as the power limit; wherein, the remaining available safe current in the power supply circuit of the charging pile is the difference between the current threshold of the power supply circuit of the charging pile, the current in the power supply circuit of the charging pile, and the second margin current. If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold of the power supply circuit where the charging pile is located and the first margin current, then the minimum charging power of the charging pile is determined as the power limit after the charging pile is started.

[0008] In one possible implementation, determining the power limit based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, and the state of the charging pile, includes: When the charging pile is in a charging state, if the current of the power supply circuit where the charging pile is located is less than the difference between the current threshold and the second margin current of the power supply circuit where the charging pile is located for N consecutive sampling times, then the sum of the remaining available safe current of the power supply circuit where the charging pile is located and the current of the charging pile is determined, and the product of the sum and the phase sequence voltage of the charging pile is determined as the power limit, where N is an integer greater than 1; If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold and the second margin current in the power supply circuit where the charging pile is located, and the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is greater than or equal to 0, then the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is determined, and the product of the sum and the phase sequence voltage where the charging pile is located is determined as the power limit. If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold and the second margin current in the power supply circuit where the charging pile is located, and the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is less than 0, then the minimum charging power of the charging pile is determined as the power limit.

[0009] In one possible implementation, when the charging pile is connected to the second circuit breaker, if the current specification of the main inlet switch is less than or equal to the reference value of the maximum inlet current, the current threshold of the power supply circuit where the charging pile is located is the current specification of the main inlet switch; if the current specification of the main inlet switch is greater than the reference value of the maximum inlet current, the current threshold of the power supply circuit where the charging pile is located is the reference value of the maximum inlet current. When the charging pile is connected to the second circuit breaker and the second circuit breaker is offline, or when the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, the current threshold of the power supply circuit where the charging pile is located is the current specification of the main switch.

[0010] In one possible implementation, determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic energy storage and charging system includes: When the charging pile is connected to the second circuit breaker and the operating condition indicates that the second circuit breaker is online and the inverter is offline, the difference between the maximum inlet current reference value and the load current of the phase sequence where the charging pile is located is calculated, and the product of the difference and the current of the charging pile and the voltage of the phase sequence where the charging pile is located is determined as the power limit value.

[0011] In one possible implementation, determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic energy storage and charging system includes: When the charging pile is connected to the second circuit breaker and the operating condition indicates that the second circuit breaker is offline, the inverter is offline or faulty, the minimum charging power of the charging pile is determined as the power limit. or, When the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, and the operating condition indicates that the inverter is offline or faulty, the minimum charging power of the charging pile is determined as the power limit.

[0012] In one possible implementation, determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic energy storage and charging system includes: When the operating condition indicates that a high-power device is started, the minimum charging power of the charging pile is determined as the power limit within a preset time after the high-power device starts. After the preset time period, the process returns to the step of determining the power limit of the charging pile based on the operating conditions and the access location of the charging pile in the photovoltaic energy storage and charging system.

[0013] The second aspect of this application provides a controller for executing the charging power control method of a charging pile according to the first aspect or any implementation thereof.

[0014] A third aspect of this application provides a photovoltaic energy storage and charging system, including: a controller, an intelligent distribution box, an inverter, and multiple loads; The inverter's DC side is connected to a DC power supply, which includes at least one of a photovoltaic module and an energy storage battery. The inverter's AC side grid connection port is connected to the power grid sequentially through the first circuit breaker in the smart distribution box and the main switch outside the smart distribution box; The AC side load port of the inverter is connected to all or part of the load through the second circuit breaker in the intelligent distribution box. Multiple loads include charging stations; The controller is communicatively connected to the intelligent distribution box, the inverter, and the charging pile, and is used to execute the charging power control method of the charging pile according to the first aspect or any implementation thereof.

[0015] In one possible implementation, the charging pile is connected to the second circuit breaker, or the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box.

[0016] By employing the above technical solutions, the charging power control method, controller, and photovoltaic-energy storage-charging system provided in this application acquire the operating conditions of the photovoltaic-energy storage-charging system, which indicate the status of the inverter and the second circuit breaker, as well as the changes in the power load of the photovoltaic-energy storage-charging system. Based on the status of the inverter and the second circuit breaker, the changes in the power load of the photovoltaic-energy storage-charging system, and the connection location of the charging pile in the photovoltaic-energy storage-charging system, the power limit of the charging pile is adjusted in real time. This solves the problem that charging at a fixed maximum power can easily lead to overload tripping of the power distribution system, thus achieving optimized application of charging and power consumption in the photovoltaic-energy storage-charging system. Attached Figure Description

[0017] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0018] Figure 1 A schematic flowchart of a charging power control method for a charging pile provided in an embodiment of this application; Figure 2 A schematic diagram of an optical storage and charging system provided in an embodiment of this application; Figure 3 This is a schematic diagram of another optical storage and charging system provided in an embodiment of this application; Figure 4 A flowchart illustrating a method for determining the power limit of a charging pile, provided in an embodiment of this application; Figure 5 A flowchart illustrating another method for determining the power limit of a charging pile, provided in an embodiment of this application; Figure 6 This is a schematic diagram of a controller provided in an embodiment of this application. Detailed Implementation

[0019] The embodiments of this application are described below with reference to the accompanying drawings. The terminology used in the implementation section of this application is for explaining specific embodiments only and is not intended to limit the scope of this application.

[0020] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0021] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0022] This application provides a charging power control method for a charging pile. The charging power control method of this application embodiment will be described in detail below with reference to the accompanying drawings.

[0023] Reference Figure 1 , Figure 1 This is a flowchart illustrating a charging power control method for a charging pile provided in an embodiment of this application, as shown below. Figure 1 As shown in the embodiment of this application, a charging power control method for a charging pile may include steps 101 to 103, which are described in detail below.

[0024] 101: Obtain the operating status of the photovoltaic storage and charging system.

[0025] The photovoltaic-storage-charging system includes: a smart distribution box, an inverter, and multiple loads, including charging piles, as well as important loads such as lighting equipment and refrigerators, and conventional loads such as air conditioners, washing machines, and water heaters.

[0026] The DC side of the inverter is connected to a DC power supply. The AC side grid connection port of the inverter is connected to the power grid in sequence through the first circuit breaker in the smart distribution box and the main switch outside the smart distribution box. The AC side load port of the inverter is connected to all or part of the load through the second circuit breaker in the smart distribution box.

[0027] Charging piles can be connected to different locations within the photovoltaic-storage-charging system.

[0028] Please see Figure 2 The schematic diagram of the photovoltaic energy storage and charging system shown indicates that the charging pile can be used as a second circuit breaker in the intelligent power distribution box to connect the load.

[0029] Please see Figure 3 The schematic diagram of the photovoltaic energy storage and charging system shown indicates that the charging pile can also be connected to the outside of the smart distribution box and is located on the power circuit between the outgoing end of the main switch and the incoming end of the smart distribution box.

[0030] The above two charging pile access locations are merely examples, and the embodiments of this application are not limited thereto.

[0031] The operating status of the photovoltaic-energy storage-charging system indicates the state of the inverter and the second circuit breaker, as well as the changes in the system's electrical load. The controller in the system communicates with the inverter and the second circuit breaker to obtain their states. The inverter's state includes: online, offline, and fault; the second circuit breaker's state includes: online, offline, and not configured. The controller communicates with the battery management system (EMS) to monitor whether the energy storage battery has started charging, and collects the circuit breaker current of high-power electrical equipment to monitor whether high-power electrical equipment has started, thus obtaining the changes in the system's electrical load.

[0032] 102: Determine the power limit of the charging pile based on the operating conditions of the photovoltaic-storage-charging system and the connection location of the charging pile in the system.

[0033] The operating conditions of the photovoltaic-storage system represent the status of the inverter and the second circuit breaker, as well as the changes in the power load of the photovoltaic-storage-charging system. Therefore, the power limit of the charging pile is determined based on the operating conditions of the photovoltaic-storage-charging system, and the photovoltaic modules and energy storage batteries connected to the DC side of the charging pile inverter are effectively linked to obtain the optimal charging power of the charging pile from the perspective of the overall energy storage system based on the changes in power load.

[0034] The location of the charging pile within the photovoltaic-energy storage-charging system affects the power supply circuit it's connected to, and consequently, the current threshold of that circuit. When the charging pile is connected to a second circuit breaker, its power supply circuit is a dedicated branch circuit of the smart distribution box. When the charging pile is connected to the power supply circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, its power supply circuit is the main circuit of the main switch, carrying the total current for both the charging pile and all other loads.

[0035] 103: Send power control commands to the charging pile according to the power limit.

[0036] Charging stations have power adjustment functions, but the charging power of a charging station is limited by the on-board charger. Some models have on-board chargers with preset power adjustment functions, such as some on-board chargers with power adjustment functions of 1.38-7kW; some models have on-board chargers with multi-level power adjustment functions, such as some on-board chargers with three levels of power adjustment functions of 2.2kW, 3.5kW, and 7kW.

[0037] In one possible implementation, for application scenarios where the on-board charger has a power adjustment function within a preset range, a power control command carrying a power limit value is sent to the charging pile, so that the charging pile charges at the power limit value.

[0038] In another possible implementation, for application scenarios where the on-board charger has multi-level power adjustment function, or for the purpose of being compatible with all vehicle models, i.e., without distinguishing between on-board chargers of different vehicle models, the power limit is first converted into a power adjustment level, and then a power control command carrying the power adjustment level is sent to the charging pile, so that the charging pile charges at the power corresponding to the power adjustment level.

[0039] This embodiment provides a charging power control method for charging piles. It obtains the operating conditions of the photovoltaic-storage-charging system, which represent the status of the inverter and the second circuit breaker, as well as the changes in the power load of the photovoltaic-storage-charging system. Based on the status of the inverter and the second circuit breaker, the changes in the power load of the photovoltaic-storage-charging system, and the connection position of the charging pile in the photovoltaic-storage-charging system, the power limit of the charging pile is adjusted in real time. This solves the problem that charging at a fixed maximum power can easily lead to overload tripping of the power distribution system, and realizes the optimized application of charging and power consumption in the photovoltaic-storage-charging system.

[0040] For the sake of simplicity, the following definition defines connecting the charging pile to the second circuit breaker as the first position of the charging pile connection, and connecting the charging pile to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box as the second position of the charging pile connection.

[0041] In one possible implementation, the operating conditions of the photovoltaic-storage-charging system include: normal operating conditions and special operating conditions. The special operating conditions include: high-power equipment startup operating conditions, inverter offline operating conditions, etc. Therefore, step 103 in the above embodiments includes multiple implementation methods. The following describes the charging pile power limiting strategy corresponding to each operating condition, that is, the implementation method of step 103 in the above embodiments under each operating condition.

[0042] Normal operating conditions: Normal operating condition refers to the condition where the inverter is online and no high-power devices are started. High-power devices include: electrical appliances whose instantaneous starting power exceeds a first threshold (such as air conditioners), and energy storage batteries whose instantaneous starting charging power exceeds a second threshold. The first and second thresholds are set according to the actual application scenario, and this application embodiment does not impose specific limitations. The charging pile power limiting strategy corresponding to normal operating condition includes the following steps 201-203: 201: Based on the access location of the charging pile in the photovoltaic energy storage and charging system, obtain the current of the power extraction circuit where the charging pile is located.

[0043] When the charging pile is connected to the first position, the load current of the phase sequence where the charging pile is located ( ) and photo-storage current ( The vector sum of ) is determined as the current (IX charging) in the power supply circuit where the charging pile is located.

[0044] When the inverter's active power is ≥0, the photovoltaic storage current flows from the inverter to the power extraction circuit where the charging pile is located: ; When the inverter's active power is less than 0, the photovoltaic storage current flows from the power extraction circuit where the charging pile is located to the inverter: ; in: ; If the load includes both regular and critical loads, then , This is the normal load current. For important load current; As the reference phase for vector synthesis, , These are the power factor and inverse cosine phase angle of the corresponding load.

[0045] The above , The active power of the inverter is collected by the second circuit breaker and provided to the controller. It is supplied to the controller by the inverter.

[0046] When the charging pile is connected to the second location, based on the total active power entering the household ( ), the phase sequence voltage (U) and power factor (cos) of the charging pile Determine the current (IY charging) of the power supply circuit where the charging pile is located.

[0047] Specifically, IY charge = P 总 / (3U×cos ); Where: P 总 =P 负载 +P 充电桩 +P 光储 P 负载 P 充电桩 P 光储 The power supply to the controller is provided by the smart distribution box, charging pile, and inverter, respectively. If the second circuit breaker in the smart distribution box is offline, the default P will be used. 负载 Calculate P 总 ; cos It can be set to 0.9.

[0048] 202: Get the status of the charging station.

[0049] The controller communicates with the charging station to obtain the status of the charging station.

[0050] The charging station's status includes: not started and charging.

[0051] 203: Determine the power limit of the charging pile based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, as well as the status of the charging pile.

[0052] I-threshold is the current specification of the main inlet switch, which is the upper limit of hardware safety for the main inlet circuit. It is determined by the rated current of the main inlet switch. If the current in the main inlet circuit exceeds I-threshold, it will trigger the trip protection.

[0053] IX charging threshold is the current threshold of the power supply circuit where the charging pile is located, which is the upper limit of software control set for the charging pile.

[0054] The maximum current reference value for the incoming line is set according to the industry's general circuit design standards, such as 63A.

[0055] When the charging pile is connected to the first position, if the current specification (I threshold) of the main power switch is less than or equal to the maximum current reference value of the main power supply, it indicates that the maximum carrying capacity of the main power supply circuit is weak. In this case, the threshold value (IX charging threshold) of the power supply circuit where the charging pile is located needs to be aligned with the current specification of the main power supply. That is, the current threshold value (IX charging threshold) of the power supply circuit where the charging pile is located is set to the current specification of the main power supply. This ensures that the upper limit of software control does not exceed the hardware baseline and avoids triggering tripping in advance through power adjustment. If the current specification (I threshold) of the main power supply is greater than the maximum current reference value of the main power supply, it indicates that the maximum carrying capacity of the main power supply circuit is strong. Therefore, the current threshold value of the power supply circuit where the charging pile is located can be set to the maximum current reference value of the main power supply, in accordance with the industry's general circuit design standards. This will not waste the carrying capacity of the main power supply circuit and will also avoid local overload of branch circuits.

[0056] The second circuit breaker is a load status sensing node in the intelligent distribution box, capable of monitoring the real-time current of the corresponding circuit. When the charging pile is connected to the first position, the controller can obtain the accurate current of the circuit where the charging pile is located through the second circuit breaker when the second circuit breaker is online. However, when the second circuit breaker is offline, the controller cannot obtain the accurate current of the circuit where the charging pile is located through the second circuit breaker. In order to avoid the power limit calculation deviation caused by data loss and the resulting circuit overload, the current of the power supply circuit where the charging pile is located is determined based on the total active power entering the house, the phase sequence voltage of the charging pile, and the power factor. The current threshold of the power supply circuit where the charging pile is located is the current specification (I threshold) of the main switch entering the house.

[0057] When the charging pile is connected to the second location, the current of the power supply circuit where the charging pile is located is determined based on the total active power entering the house, the phase sequence voltage where the charging pile is located, and the power factor. The current threshold of the power supply circuit where the charging pile is located is the specification of the total circuit breaker current entering the house (I threshold).

[0058] When the charging station is connected to the first location, please refer to Figure 4 The method for determining the power limit of a charging pile includes the following steps 401-411.

[0059] 401: Is the charging station currently charging? If the charging station is not started, execute 402: Get the current IX of the power supply circuit where the charging station is located; 403: Is IX charging < IX charging threshold - first margin current? The first margin current represents the margin reserved for the current surge when the charging pile starts charging. It is set according to the actual application scenario. For example, it can be set to 10A to offset the current surge on the power supply circuit where the charging pile is located when it starts charging.

[0060] If IXcharge < IXthreshold - first margin current, it means that the residual current in the power supply circuit where the charging pile is located is sufficient before the charging pile is started, and the impact margin for the charging pile to start is reserved.

[0061] If IX_charge ≥ IX_charge threshold - first margin current, it means that the residual current in the power supply circuit where the charging pile is located is insufficient before the charging pile starts, and cannot offset the current surge when the charging pile starts.

[0062] Therefore, if IX_charge < IX_charge threshold - first margin current, execute 404: power limit of charging pile = (IX_charge threshold - IX_charge - second margin current) × U; allocate the remaining current of the power supply circuit where the charging pile is located to the charging pile to maximize charging power and improve charging efficiency.

[0063] If IX_charge ≥ IX_charge threshold - first margin current, execute 405: power limit of charging pile = minimum charging power of charging pile; start charging pile directly with minimum power to avoid circuit overload tripping.

[0064] If the charging station is in charging mode, execute 406: Is IX charging ≥ IX charging threshold - second margin current; The second margin current represents the current redundancy margin for the steady-state operation of the charging pile. It is set according to the actual application scenario. For example, it can be set to 4A, which is equivalent to leaving "elastic space" for the power supply circuit where the charging pile is located, so as to offset the impact of small current fluctuations in the power supply circuit where the charging pile is located on the calculation of the power limit of the charging pile.

[0065] If IX charge < IX charge threshold - second margin current, execute 407: whether IX charge < IX charge threshold - second margin current for N consecutive sampling times; N is an integer greater than 1. For example, N can be set to 2. By judging whether IX charging < IX charging threshold - second margin current for N consecutive sampling times, the influence of current fluctuation on current judgment is filtered.

[0066] If for N consecutive sampling times IX_charge < IX_charge threshold - second margin current, it means that the residual current in the power supply circuit where the charging pile is located is sufficient under the condition of filtering current fluctuations. Execute 408: Power limit of charging pile = (I_charge + IX_charge threshold - IX_charge - second margin current) × U; Distribute the residual current in the power supply circuit where the charging pile is located to the charging pile to maximize charging power and improve charging efficiency.

[0067] If IX_charge ≥ IX_charge threshold - second margin current, it indicates that the residual current in the power supply circuit where the charging pile is located is insufficient. It is necessary to execute 409: Is I_charge + IX_charge threshold - IX_charge - second margin current ≥ 0? to further determine whether the current of the charging pile is too large.

[0068] If Icharge + IXcharge threshold - IXcharge - second margin current ≥ 0, it means that the current in the power supply circuit where the charging pile is located is close to the threshold, and the current of the charging pile can cover the margin gap. By executing 410: Power limit of charging pile = (Icharge + IXcharge threshold - IXcharge - second margin current) × U; the power limit of the charging pile is corrected according to the current of the charging pile to ensure that the current in the power supply circuit where the charging pile is located does not exceed the threshold.

[0069] If Icharge + IXcharge threshold - IXcharge - second margin current < 0, it means that the current in the power supply circuit where the charging pile is located is approaching the threshold, and the current of the charging pile cannot make up for the margin gap. By executing 411: the power limit of the charging pile = the minimum charging power of the charging pile, the charging pile charges at the minimum power to avoid circuit overload tripping.

[0070] If the charging pile is connected to the first position and the second circuit breaker is offline, or if the charging pile is connected to the second position, please refer to [the relevant documentation]. Figure 5 The method for determining the power limit of a charging pile includes the following steps 501-511.

[0071] 501: Is the charging station currently charging? If the charging station is not started, execute 502: Get the current IY of the power supply circuit where the charging station is located; 503: Is IY charging < I threshold - first margin current? If IYcharge < Ithreshold - first margin current, execute 504: Power limit of charging pile = (Ithreshold - IYcharge - second margin current) × U; If IY_charge ≥ I_threshold - first margin current, execute 505: power limit of charging pile = minimum charging power of charging pile; If the charging station is in charging mode, execute 506: Is IY charging ≥ I threshold - second margin current; If IYcharge < Ithreshold - second margin current, execute 507: whether IYcharge < Ithreshold - second margin current for N consecutive sampling times; If IY_charge < I_threshold - second margin current for N consecutive sampling times, execute 508: Power limit of charging pile = (I_charge + I_threshold - IY_charge - second margin current) × U; If IYcharge ≥ Ith threshold - second margin current, execute 509: Is Icharge + Ith threshold - IYcharge - second margin current ≥ 0? If Icharge + Ithreshold - IY charge - second margin current ≥ 0, execute 510: power limit of charging pile = (Icharge + Ithreshold - IY charge - second margin current) × U; If Icharge + Ithreshold - IY charge - second margin current < 0, execute 511: power limit of charging pile = minimum charging power of charging pile.

[0072] Steps 501-511 are similar to the power limiting principle of steps 401-411 above, the difference being that the current in the power supply circuit where the charging pile is located is different, and the current threshold of the power supply circuit where the charging pile is located is different.

[0073] Special working condition 1: With the second circuit breaker online and the inverter offline, and the charging pile connected to the first position, the inverter being offline prevents it from providing the photovoltaic storage current to the controller. This results in the loss of key parameters for calculating the current in the power supply circuit where the charging pile is located. To avoid circuit overload problems caused by incorrect power limit calculations, the maximum inlet current benchmark value is calculated. -I charge, obtain the remaining available current in the power supply circuit where the charging pile is located, and thus determine the power limit of the charging pile to ensure circuit safety. The specific power limit of the charging pile = (maximum inlet current base value - ... -I charge)×U.

[0074] Special operating condition 2: When a charging pile is connected to the first location, the determination of the charging pile's power limit depends on the real-time data feedback from the inverter and the second circuit breaker. In the event that the second circuit breaker is offline, the inverter is offline, or there is a fault, the controller cannot obtain the real-time data feedback from the inverter and the second circuit breaker. In order to avoid circuit overload problems caused by incorrect power limit calculation, the power limit of the charging pile is set to the minimum charging power of the charging pile to ensure circuit safety.

[0075] When the charging pile is connected to the second location, the controller obtains the magnitude and direction of the photovoltaic and energy storage power provided by the inverter (discharging to offset the total load, charging to increase the total load). This is the key basis for calculating the current IY of the power supply circuit where the charging pile is located, and directly determines the upper limit of the power that the charging pile can be allocated. If the inverter is offline or malfunctioning, the controller cannot obtain the above data. To avoid circuit overload problems caused by incorrect power limit calculations, the power limit of the charging pile is set to the minimum charging power of the charging pile to ensure circuit safety.

[0076] Special operating condition 3: When a high-power device is started in the operation mode of the photovoltaic-storage-charging system, such as a high-power electrical appliance like an air conditioner or a high-power energy storage battery starting to charge, priority is given to ensuring the power demand of the high-power electrical appliance or the energy storage demand of the high-power energy storage battery within a preset time (e.g., 10 minutes) after the high-power device starts. This results in a significant reduction in the remaining available safe current in the power supply circuit where the charging pile is located. If the charging pile is still operating at a high charging power at this time, there is a risk of tripping. Therefore, the minimum charging power of the charging pile is determined as the power limit to avoid overloading of the power supply circuit where the charging pile is located.

[0077] In this mode, the inverter operates in a forced battery charging state, and the high-power energy storage battery starts charging. The inverter can operate in either storm mode or backup power mode.

[0078] In response to weather warning signals or manual commands triggered by the inverter, the controller forces the inverter to draw power from the grid at maximum power to fast charge the energy storage battery. The goal is to charge the battery to 100% SOC (State of Charge) before a disaster strikes, ensuring that critical loads (refrigerators, lighting, emergency power supplies, etc.) can be powered by the energy storage battery after a power outage. In this case, the energy storage battery charging takes priority over charging piles and ordinary loads, which is a special operating condition of "energy reserve priority".

[0079] When the controller detects that the SOC of the energy storage battery is lower than a preset threshold (such as 30%), or meets the preset "peak-valley electricity price off-peak charging", the controller controls the inverter to force power to draw power from the grid to charge the energy storage battery, ensuring that the energy storage battery always maintains sufficient reserve power to cope with sudden power outages. This is also a special operating condition of "energy reserve priority".

[0080] After a preset startup time for high-power equipment, its operating power may decrease. For example, a variable frequency air conditioner has a high initial power consumption upon startup, which decreases after a period of time. To avoid excessive power limiting of the charging pile and to effectively utilize the remaining available safe current in the power supply circuit where the charging pile is located, the power limit for the charging pile is determined after the preset startup time based on the operating conditions of the photovoltaic-energy storage-charging system and the connection location of the charging pile within the system. For details, please refer to the above-mentioned normal operating condition, special operating condition 1, and special operating condition 2.

[0081] The preset duration for different types of high-power devices can be the same or different. In one possible implementation, the preset duration for high-power devices is set based on the historical operating power data of the high-power devices.

[0082] This application provides a charging power control method for a charging pile, which effectively links the charging pile with photovoltaic, energy storage, and load. Combining normal and special operating conditions, it determines the power limit of the charging pile from a global perspective, so that the energy of the photovoltaic-energy storage-charging system can be fully utilized. Under the premise of ensuring circuit safety, it maximizes the satisfaction of charging demand and achieves an effective balance between charging efficiency and power safety of the charging pile.

[0083] This application also provides a controller for executing any of the charging power control methods for charging piles provided in this application. The controller can be a standalone controller or integrated into a smart distribution box.

[0084] In one possible implementation, see Figure 6 This figure is a schematic diagram of a controller provided in an embodiment of this application.

[0085] The controller may include a memory 601 and a processor 602. The processor 602 can communicate with the smart distribution box, inverter, and charging pile, and can obtain the status of the second circuit breaker in the smart distribution box, the status of the inverter, and the status of the charging pile, and send power control commands to the charging pile. Figure 6 As shown, the memory can be random access memory (RAM), flash memory, read-only memory (ROM), EPROM, non-volatile read-only memory (Electronic Programmable ROM), registers, hard disks, removable disks, etc.

[0086] The memory 601 can store computer instructions. When the computer instructions stored in the memory 601 are executed by the processor 602, the processor 602 can be used to execute the charging power control method of the charging pile. The memory 602 can also store data, such as threshold information involved in the above embodiments.

[0087] This application also provides a computer program product including computer-readable instructions, which, when executed on a controller, cause the controller to implement any of the charging power control methods for charging piles provided in this application.

[0088] This application also provides a computer-readable storage medium carrying one or more computer programs. When the one or more computer programs are executed by a controller, the controller can implement any of the charging power control methods for charging piles provided in this application.

[0089] This application embodiment also provides a photovoltaic energy storage and charging system, including: a controller, a smart distribution box, an inverter, and multiple loads; The inverter's DC side is connected to a DC power supply, which includes at least one of a photovoltaic module and an energy storage battery. The inverter's AC side grid connection port is connected to the power grid sequentially through the first circuit breaker in the smart distribution box and the main switch outside the smart distribution box; The AC side load port of the inverter is connected to all or part of the load through the second circuit breaker in the intelligent distribution box. Multiple loads include charging stations; The controller is communicatively connected to the intelligent distribution box, the inverter, and the charging pile, and is used to execute any of the charging power control methods for charging piles provided in the embodiments of this application.

[0090] In one possible implementation, such as Figure 2 As shown, the charging pile is connected to the second circuit breaker, or as... Figure 3 As shown, the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box.

[0091] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the device embodiment drawings provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0092] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0093] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0094] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A method for controlling the charging power of a charging pile, characterized in that, include: The system obtains the operating status of a photovoltaic-storage-charging system, which includes a smart distribution box, an inverter, and multiple loads, including charging piles. The DC side of the inverter is connected to a DC power supply, and the AC side grid connection port of the inverter is connected to the power grid sequentially through a first circuit breaker in the smart distribution box and a main switch outside the smart distribution box. The AC side load port of the inverter is connected to all or part of the loads through a second circuit breaker in the smart distribution box. The operating status indicates the state of the inverter and the second circuit breaker, as well as the changes in the power load of the photovoltaic-storage-charging system. Based on the operating conditions and the access location of the charging pile in the photovoltaic energy storage and charging system, the power limit of the charging pile is determined. A power control command is sent to the charging pile according to the power limit.

2. The charging power control method for a charging pile according to claim 1, characterized in that, Determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic-storage-charging system includes: When the inverter is online and no high-power equipment is started in the operating condition, the current of the power extraction circuit where the charging pile is located is obtained according to the access location of the charging pile in the photovoltaic energy storage charging system. The high-power equipment includes: electrical equipment with a starting instantaneous power greater than a first threshold and energy storage battery with a starting charging instantaneous power greater than a second threshold. Obtain the status of the charging pile; The power limit is determined based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, as well as the status of the charging pile.

3. The charging power control method for a charging pile according to claim 2, characterized in that, The step of obtaining the current of the power extraction circuit where the charging pile is located based on the connection location of the charging pile in the photovoltaic energy storage and charging system includes: When the charging pile is connected to the second circuit breaker, the vector sum of the load current and the photovoltaic storage current in the phase sequence where the charging pile is located is determined as the current of the power extraction circuit where the charging pile is located. When the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, the current of the power supply circuit where the charging pile is located is determined based on the total active power of the household, the phase sequence voltage of the charging pile, and the power factor.

4. The charging power control method for a charging pile according to claim 2, characterized in that, The step of determining the power limit based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, and the status of the charging pile, includes: When the charging pile is not activated, if the current in the power supply circuit of the charging pile is less than the difference between the current threshold of the power supply circuit and the first margin current, then after the charging pile is activated, the product of the remaining available safe current in the power supply circuit of the charging pile and the phase sequence voltage of the charging pile is determined as the power limit; wherein, the remaining available safe current in the power supply circuit of the charging pile is the difference between the current threshold of the power supply circuit of the charging pile, the current in the power supply circuit of the charging pile, and the second margin current. If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold of the power supply circuit where the charging pile is located and the first margin current, then the minimum charging power of the charging pile is determined as the power limit after the charging pile is started.

5. The charging power control method for a charging pile according to claim 4, characterized in that, The step of determining the power limit based on the relationship between the current in the power supply circuit where the charging pile is located and the current threshold of the power supply circuit where the charging pile is located, and the status of the charging pile, includes: When the charging pile is in a charging state, if the current of the power supply circuit where the charging pile is located is less than the difference between the current threshold and the second margin current of the power supply circuit where the charging pile is located for N consecutive sampling times, then the sum of the remaining available safe current of the power supply circuit where the charging pile is located and the current of the charging pile is determined, and the product of the sum and the phase sequence voltage of the charging pile is determined as the power limit, where N is an integer greater than 1; If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold and the second margin current in the power supply circuit where the charging pile is located, and the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is greater than or equal to 0, then the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is determined, and the product of the sum and the phase sequence voltage where the charging pile is located is determined as the power limit. If the current in the power supply circuit where the charging pile is located is greater than or equal to the difference between the current threshold and the second margin current in the power supply circuit where the charging pile is located, and the sum of the remaining available safe current in the power supply circuit where the charging pile is located and the charging pile current is less than 0, then the minimum charging power of the charging pile is determined as the power limit.

6. The charging power control method for a charging pile according to claim 5, characterized in that, When the charging pile is connected to the second circuit breaker, if the current specification of the main inlet switch is less than or equal to the reference value of the maximum inlet current, the current threshold of the power supply circuit where the charging pile is located is the current specification of the main inlet switch; if the current specification of the main inlet switch is greater than the reference value of the maximum inlet current, the current threshold of the power supply circuit where the charging pile is located is the reference value of the maximum inlet current. When the charging pile is connected to the second circuit breaker and the second circuit breaker is offline, or when the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, the current of the power supply circuit where the charging pile is located is determined based on the total active power of the household, the phase sequence voltage of the charging pile, and the power factor. The current threshold of the power supply circuit where the charging pile is located is the current specification of the main switch.

7. The charging power control method for a charging pile according to claim 1, characterized in that, Determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic-storage-charging system includes: When the charging pile is connected to the second circuit breaker and the operating condition indicates that the second circuit breaker is online and the inverter is offline, the difference between the maximum inlet current reference value and the load current of the phase sequence where the charging pile is located is calculated, and the product of the difference and the current of the charging pile and the voltage of the phase sequence where the charging pile is located is determined as the power limit value.

8. The charging power control method for a charging pile according to claim 1, characterized in that, Determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic-storage-charging system includes: When the charging pile is connected to the second circuit breaker and the operating condition indicates that the second circuit breaker is offline, the inverter is offline or faulty, the minimum charging power of the charging pile is determined as the power limit. or, When the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box, and the operating condition indicates that the inverter is offline or faulty, the minimum charging power of the charging pile is determined as the power limit.

9. The charging power control method for a charging pile according to any one of claims 1-8, characterized in that, Determining the power limit of the charging pile based on the operating conditions and the connection location of the charging pile in the photovoltaic-storage-charging system includes: When the operating condition indicates that a high-power device is started, the minimum charging power of the charging pile is determined as the power limit within a preset time after the high-power device starts. After the preset time period, the process returns to the step of determining the power limit of the charging pile based on the operating conditions and the access location of the charging pile in the photovoltaic energy storage and charging system.

10. A controller, characterized in that, The charging power control method for executing the charging pile according to any one of claims 1-9.

11. A photovoltaic energy storage and charging system, characterized in that, include: Controller, smart distribution box, inverter, and multiple loads; The inverter's DC side is connected to a DC power supply, which includes at least one of a photovoltaic module and an energy storage battery. The inverter's AC side grid connection port is connected to the power grid sequentially through the first circuit breaker in the smart distribution box and the main switch outside the smart distribution box; The AC side load port of the inverter is connected to all or part of the load through the second circuit breaker in the intelligent distribution box. Multiple loads include charging stations; The controller is communicatively connected to the intelligent distribution box, the inverter, and the charging pile, and is used to execute the charging power control method of the charging pile according to any one of claims 1-9.

12. The photovoltaic energy storage and charging system according to claim 11, characterized in that, The charging pile is connected to the second circuit breaker, or the charging pile is connected to the power circuit between the outgoing terminal of the main switch and the incoming terminal of the smart distribution box.

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