A power control system and power control method for preventing backflow and overdraw

Abstract

The present disclosure provides a power control system and method for preventing reverse flow and over demand, wherein the power control system comprises a power regulating unit, a power grid and a power supply unit. The power regulating unit is connected to the power grid and configured to obtain a first grid-side power of the power grid and determine whether there is reverse flow or over demand based on the first grid-side power. The power regulating unit is also connected to the power supply unit and further configured to obtain a second grid-side power of the power grid and an output power of the power supply unit in the case of reverse flow or over demand, and adjust the output power based on the second grid-side power. The transmission delay of the second grid-side power is less than that of the first grid-side power. In this way, in the case of detecting over demand or reverse flow, the power regulating unit can quickly adjust the output power of the power supply unit to match the actual demand of the load and maintain the stable operation of the power grid.

Description

Technical Field

[0001] This disclosure relates to the field of power control, and more particularly to a power control system and a power control method. Background Technology

[0002] Under normal inverter operation, the load will continuously increase and decrease. The inverter needs to be manually adjusted to match the required power output to the load. If the operator fails to do so in a timely manner, the inverter's output power may exceed the load's needs, resulting in excess energy flowing into the grid and causing unpredictable damage to the grid. Conversely, the inverter's output power may also fall short of the load's requirements, in which case it will draw power from the grid to compensate, causing significant economic losses to the customer. Both scenarios result in substantial, even incalculable, losses, as well as wasted human resources and effort.

[0003] Currently, the anti-backflow / anti-over-demand strategies for energy storage scenarios on the market take approximately 10-16 seconds to complete, which fails to meet the latest anti-backflow standards. While anti-over-demand strategies lack specific metrics, they can still complete within the required timeframe, similar to anti-backflow strategies. Summary of the Invention

[0004] In view of this, embodiments of the present disclosure provide a power control system and power control method for preventing backflow and over-demand, so as to improve the processing speed of the anti-backflow / anti-over-demand strategy.

[0005] The technical solution of this invention is implemented as follows:

[0006] This disclosure provides a power control system, including: a power regulation unit, a power grid, and a power supply unit; wherein, the power regulation unit is connected to the power grid and configured to acquire a first grid-side power of the power grid, and determine whether there is reverse current or over-demand based on the first grid-side power; the power regulation unit is connected to the power supply unit and is further configured to acquire a second grid-side power of the power grid and the output power of the power supply unit when reverse current or over-demand exists, and adjust the output power based on the second grid-side power; wherein, the transmission delay of the second grid-side power is less than that of the first grid-side power.

[0007] In the above scheme, the power adjustment unit is configured to acquire the redundant power of the power grid and determine the adjustment range of the output power based on the redundant power of the power grid and the second grid-side power.

[0008] In the above scheme, the power supply unit includes: multiple power supply units; wherein, the power adjustment unit is connected to the multiple power supply units, and is further configured to acquire the adjustment time and the operating parameters of the multiple power supply units, and set the power change curve of each power supply unit based on the adjustment time, the operating parameters and the adjustment range.

[0009] In the above scheme, the power control system includes: a first link and a second link; wherein, the power adjustment unit connects the power grid and the power supply unit through the first link and the second link; the transmission delay of the first link is less than that of the second link; the operating parameters, the output power and the second grid-side power are all transmitted through the first link; the first grid-side power is transmitted through the second link.

[0010] In the above scheme, the redundant power includes: excess power and reverse current power; the power adjustment unit is configured to adjust the adjustment range to the difference between the reverse current power and the second grid-side power when reverse current exists; or, when excess demand exists, adjust the adjustment range to the difference between the excess power and the second grid-side power.

[0011] In the above scheme, the adjustment time is less than 2 seconds.

[0012] In the above scheme, the operating parameters include one or more of the following: battery state of charge, battery temperature, and battery health; and / or, the operating parameters include one or more of the following: number of photovoltaic modules, number of channels at maximum power point, and illuminance.

[0013] This disclosure also provides a power control method, comprising: acquiring a first grid-side power of the power grid, and determining whether there is reverse current or over-demand based on the first grid-side power; if there is reverse current or over-demand, acquiring a second grid-side power of the power grid and the output power of the power supply unit, and adjusting the output power based on the second grid-side power; wherein the transmission delay of the second grid-side power is less than that of the first grid-side power.

[0014] In the above scheme, adjusting the output power based on the second grid-side power includes: obtaining the redundant power of the power grid, and determining the adjustment range of the output power based on the redundant power of the power grid and the second grid-side power.

[0015] In the above scheme, the power supply unit includes: multiple power supply units; the power control method further includes: acquiring the adjustment time and the operating parameters of the multiple power supply units, and setting the power change curve of each power supply unit based on the adjustment time, the operating parameters and the adjustment range.

[0016] This disclosure provides a power control system, including a power regulation unit, a power grid, and a power supply unit. The power regulation unit, connected to the power grid, is configured to acquire a first grid-side power of the power grid and determine whether reverse current or over-demand exists based on the first grid-side power. The power regulation unit, connected to the power supply unit, is further configured to acquire a second grid-side power of the power grid and the output power of the power supply unit when reverse current or over-demand exists, and adjust the output power based on the second grid-side power. The transmission delay of the second grid-side power is less than that of the first grid-side power. Thus, during normal operation of the power control system, the larger delay of the first grid-side power avoids generating a large amount of repetitive or similar data in a short period. Therefore, the power regulation unit's acquisition and processing of the first grid-side power does not cause excessive resource consumption, preventing crashes or performance degradation due to overload.

[0017] Meanwhile, the power regulation unit uses a second grid-side power source with a shorter delay to adjust the output power of the power supply unit, which can significantly improve the response speed of the power regulation unit's adjustment process. Therefore, in the event of over-demand or reverse current detection, the power regulation unit can quickly adjust the output power of the power supply unit to match the actual load demand and maintain the stable operation of the power grid.

[0018] In addition, the second grid-side power and output power with smaller delays can accurately reflect the real-time status of the power supply unit and the grid, avoiding multiple adjustments by the power regulation unit, thereby reducing the adjustment time for over-demand and reverse current. Attached Figure Description

[0019] Figure 1 A schematic diagram of the power control system provided in the embodiments of this disclosure. Figure 1 ;

[0020] Figure 2 A schematic diagram of the power control system provided in the embodiments of this disclosure. Figure 2 ;

[0021] Figure 3 A schematic diagram of the power control system provided in the embodiments of this disclosure. Figure 3 ;

[0022] Figure 4 A schematic diagram of the power control system provided in the embodiments of this disclosure. Figure 4 ;

[0023] Figure 5 A schematic diagram of the power control system provided in the embodiments of this disclosure. Figure 5 ;

[0024] Figure 6 Flowchart of the power control method provided in the embodiments of this disclosure Figure 1 ;

[0025] Figure 7 Flowchart of the power control method provided in the embodiments of this disclosure Figure 2 ;

[0026] Figure 8 Flowchart of the power control method provided in the embodiments of this disclosure Figure 3 ;

[0027] Figure 9 Flowchart of the power control method provided in the embodiments of this disclosure Figure 4 ;

[0028] Figure 10 A schematic diagram of the power variation curve provided in the embodiments of this disclosure. Figure 1 ;

[0029] Figure 11 A schematic diagram of the power variation curve provided in the embodiments of this disclosure. Figure 2 . Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of this disclosure are further described in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limitations on this disclosure. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0031] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0032] If the application documents contain similar descriptions such as "first / second", the following explanation shall be added: In the following description, the terms "first / second / third" are used only to distinguish similar objects and do not represent a specific order of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing embodiments of this disclosure only and is not intended to be limiting of this disclosure.

[0034] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0035] Figure 1 This is a schematic diagram of an optional power control system 100 for preventing backflow and over-demand provided in an embodiment of this disclosure, with reference to... Figure 1 The power control system 100 includes a power regulation unit 20, a power grid 10, and a power supply unit 30. The power supply unit 30 may include one or more photovoltaic devices and energy storage devices.

[0036] In this embodiment of the disclosure, reference is made to Figure 1 The power regulation unit 20 is connected to the power grid 10. The power regulation unit 20 is configured to acquire the first grid-side power of the power grid 10 and determine whether reverse current or over-demand exists based on the first grid-side power. For example, the power grid 10 can be equipped with measuring devices such as grid-side meters, and the power regulation unit 20 can be connected to these measuring devices to acquire parameters such as voltage and current of the power grid in real time, and calculate the grid-side power of the power grid.

[0037] It should be noted that the reference Figure 1 "Backflow" refers to the unexpected return of electrical energy from the power generation system to the power grid. For example, when the power output of power supply unit 30, such as photovoltaic equipment or energy storage equipment, exceeds the power output of load 40, the excess electrical energy will be fed into the grid, causing "backflow." "Excess demand" refers to the load's electricity demand exceeding the grid's supply capacity or the agreed-upon power consumption. For example, when the power output of power supply unit 30, such as photovoltaic equipment or energy storage equipment, is less than the power output of load 40, load 40 will draw electricity from the grid, causing "excess demand." In other words, both "backflow" and "excess demand" can affect the stable operation of the power grid 10.

[0038] In this embodiment of the disclosure, reference is made to Figure 1 The power regulation unit 20 can determine whether there is reverse current or over-demand based on the power on the first grid side. For example, if the power on the first grid side is positive (i.e., the power output by the power supply unit 30 is greater than the power of the load), then the power control system 100 has a reverse current phenomenon. If the power on the first grid side is negative (i.e., the power output by the power supply unit 30 is less than the power of the load), then the power control system 100 has an over-demand phenomenon.

[0039] In this embodiment of the disclosure, reference is made to Figure 1The power regulation unit 20 is connected to the power supply unit 30. The power regulation unit 20 is also configured to acquire the second grid-side power of the power grid 10 and the output power of the power supply unit 30 in the event of reverse current or over-demand. The power regulation unit 20 is further configured to adjust the output power of the power supply unit 30 based on the second grid-side power. For example, in the event of reverse current in the power control system 100, reverse current can be prevented by reducing the output power of the power supply unit 30, and the reduction in the output power of the power supply unit 30 can be equal to the second grid-side power. In the event of over-demand in the power control system 100, over-demand can be prevented by increasing the output power of the power supply unit 30, and the increase in the output power of the power supply unit 30 can be equal to the second grid-side power.

[0040] In this embodiment of the disclosure, reference is made to Figure 1 The adjustment process of reverse current and excess demand in the power control system 100 requires a rapid response; otherwise, it will affect the normal operation of the power grid 10 and cause losses. Timely data acquisition is crucial in adjustment processes requiring rapid response. If data acquisition is not timely, it may not accurately reflect the actual state of the system, and the adjustment strategy will need to be repeatedly adjusted, making the adjustment process lengthy and inefficient. For example, if there is a delay in the acquisition of power from the second grid side of the power grid 10, it will cause a deviation in the adjustment range of the output power of the power supply unit 30. The power supply unit 30 will adjust the output power according to the deviation, resulting in excess demand or reverse current still existing in the power control system 100. Consequently, the power adjustment unit 20 needs to perform multiple repeated adjustments to eliminate the excess demand or reverse current in the power control system 100. In other words, data delay affects the adjustment process of reverse current and excess demand, prolonging the adjustment time.

[0041] In this embodiment of the disclosure, reference is made to Figure 1 The transmission delay of the second grid-side power is less than that of the first grid-side power. For example, the power regulation unit 20 can establish dual channels with the power grid 10 and the power supply unit 30 respectively. Sensitive data such as the second grid-side power are transmitted through the channel with the shorter delay, while data such as the first grid-side power are transmitted through the channel with the longer delay.

[0042] It is understood that the embodiments of this disclosure can determine whether the power control system 100 has over-demand or reverse current based on the first grid-side power. Furthermore, the output power of the power supply unit is adjusted using the second grid-side power, which has a smaller delay. Thus, during normal operation of the power control system 100, the first grid-side power has a larger delay and a lower transmission frequency, avoiding the generation of a large amount of repetitive or similar data in a short period. Therefore, the power adjustment unit 20 can collect and process the first grid-side power without causing excessive resource consumption, preventing the power adjustment unit 20 from crashing or experiencing performance degradation due to overload.

[0043] Meanwhile, the power regulation unit 20 uses the second grid-side power with a smaller delay to regulate the output power of the power supply unit 30, which can significantly improve the response speed of the regulation process of the power regulation unit 20. Thus, in the event of over-demand or reverse current detection, the power regulation unit 20 can quickly adjust the output power of the power supply unit 30 to match the actual needs of the load 40 and maintain the stable operation of the power grid 10.

[0044] In addition, the second grid-side power and output power with smaller delay can accurately reflect the real-time status of the power supply unit 30 and the power grid 10, avoiding multiple adjustments by the power regulation unit 20, thereby reducing the adjustment time for over-demand and reverse current.

[0045] Figure 2 This is a schematic diagram of another optional power control system 100 provided in this embodiment. It should be noted that the power regulation unit 20 may include a controller 210, which may be a processor such as a central processing unit (CPU). The controller 210 can monitor the first grid-side power and the second grid-side power of the power grid 10 through the grid-side meter 11. The power supply unit 30 may include one or more of an energy storage cabinet and photovoltaic solar panels. The photovoltaic inverter 301 is used to control the output power of the photovoltaic solar panels. The power conversion system (PCS) 302 is used to control the output power of the energy storage cabinet. The controller 210 can also monitor and regulate the output power of the power supply unit 30 through the photovoltaic inverter 301 or the power conversion system 302 in the power supply unit 30.

[0046] In some embodiments of this disclosure, reference is made to Figure 2 The power regulation unit 20 is configured to acquire the redundant power of the power grid 10 and determine the adjustment range of the output power based on the redundant power of the power grid 10 and the second grid-side power.

[0047] It should be noted that the output power of photovoltaic solar panels is affected by various factors such as light intensity and temperature. If the adjustment range is too large, the photovoltaic solar panels may not be able to adapt to these changes in time, resulting in unstable output. The energy storage cabinet generates heat during charging and discharging. If the power adjustment range of the energy storage cabinet is too large, the cabinet may not be able to dissipate heat in time, leading to overheating or even damage. This could potentially cause safety accidents such as battery short circuits and fires.

[0048] In this embodiment of the disclosure, reference is made to Figure 2During the actual operation of the power grid 10, a small degree of reverse current or excess demand is allowed. Therefore, the power regulation unit 20 determines the adjustment range of the output power based on the redundant power of the power grid 10 and the second grid-side power. For example, in the presence of reverse current, the controller 201 can adjust the adjustment range of the output power of the power supply unit 30 to the difference between the reverse current power and the second grid-side power. In this way, the embodiments of this disclosure can reduce the adjustment range of the output power of the power supply unit 30 while ensuring that reverse current and excess demand affecting the normal operation of the power grid 10 can be handled in a timely manner, thereby avoiding damage to the power supply unit 30.

[0049] In some embodiments of this disclosure, reference is made to Figure 1 Redundant power includes excess power and reverse current power. The power regulation unit 20 is configured to adjust the regulation range to the difference between the reverse current power and the power on the second grid side when reverse current is present. For example, when reverse current is present, the power regulation unit 20 adjusts the output power of the power supply unit 30 according to the following formula (1).

[0050] P_final = P_current - (P_network side - P_allowed backflow) Formula (1)

[0051] It should be noted that in formula (1), Pgrid side can be the power of the second grid side, Pcurrent is the output power of the power supply unit 30 before adjustment, and Pfinal is the output power of the power supply unit 30 after adjustment, that is, the target power of the power supply unit 30. Pallowed reverse flow is the reverse flow power. "Pgrid side - Pallowed reverse flow" is the adjustment range of the output power of the power supply unit 30.

[0052] In this embodiment of the disclosure, reference is made to Figure 1 In the event of excess demand, the power regulation unit 20 can adjust the regulation range to the difference between the excess power and the power on the second grid side. For example, the power regulation unit 20 adjusts the output power of the power supply unit 30 according to the following formula (2).

[0053] Pfinal = Pcurrent - (Pnetwork-side - Pallowed over-demand) (Formula 2)

[0054] It should be noted that in formula (2), Pgrid-side refers to the power on the second grid side, Pcurrent is the output power of the power supply unit 30 before adjustment, and Pfinal is the output power of the power supply unit 30 after adjustment, that is, the target power of the power supply unit 30. Pallowable reverse flow is the excess power. "Pgrid-side - Pallowable excess power" is the adjustment range of the output power of the power supply unit 30.

[0055] Figure 3 This is an optional structural diagram of an optional power control system 100 provided in this embodiment of the disclosure. It should be noted that... Figure 3The controller 210, photovoltaic inverter 301 and energy storage rheostat 302 shown can be understood with reference to Figure 2. Figure 3 The controller 210 shown establishes a first link 51 and a second link 52 with the grid-side meter, the photovoltaic inverter 301, and the energy storage transformer 302, respectively. That is, the power regulation unit is connected to the grid and the power supply unit via a first link 51 and a second link 52. More links can be established between the power regulation unit and the grid and the power supply unit; this is not limited here.

[0056] In some embodiments of this disclosure, combined with Figure 2 and Figure 3 The power control system 100 includes a first link 51 and a second link 52. The power regulation unit 20 can connect the power grid 10 and the power supply unit 30 through the first link 51 and the second link 52. The transmission delay of the first link 51 is less than that of the second link 52.

[0057] It should be noted that, in combination Figure 2 and Figure 3 When the power regulation unit 20 collects data, it usually uses protocols such as Modbus for communication. However, due to the message length limitation of the Modbus protocol, the power regulation unit 20 can only query a limited number of registers each time. Some data may not be collected and transmitted in time, which will cause a delay in the collected data.

[0058] In this embodiment of the disclosure, combined with Figure 2 and Figure 3 The power regulation unit 20 can communicate with the power grid 10 and the power supply unit 30 via the TCP / IP protocol. The power regulation unit 20 can establish a first link 51 and a second link 52 with the power grid 10 and the power supply unit 30 respectively by creating multiple sockets. Furthermore, the power regulation unit 20 can communicate with the power grid 10 and the power supply unit 30 through the first link 51 and the second link 52.

[0059] In this embodiment of the disclosure, combined with Figure 2 and Figure 3 Operating parameters, output power, and second grid-side power are all transmitted via the first link 51. The first grid-side power is transmitted via the second link 52. This results in a larger delay for the first grid-side power and a reduced transmission frequency. The power regulation unit 20's acquisition and processing of the first grid-side power does not cause excessive resource consumption, preventing it from crashing or experiencing performance degradation due to overload. The smaller delay of the second grid-side power and output power accurately reflects the real-time status of the power supply unit 30 and the power grid 10, avoiding multiple adjustments by the power regulation unit 20, thereby reducing the adjustment time for over-demand and reverse current.

[0060] It should be noted that the power regulation unit 20 can switch communication protocols to improve the data acquisition speed during the over-demand or reverse flow strategy adjustment process. For example, the power regulation unit 20 can communicate with the measuring device of the power grid 10 through the IEC104 communication protocol, thereby improving the power transmission speed of the second grid side.

[0061] In some embodiments of this disclosure, reference is made to Figure 1 The power supply unit 30 includes multiple power supply units. Among them, the power adjustment unit 20 is connected to the multiple power supply units and is also configured to acquire the adjustment time and the operating parameters of the multiple power supply units, and set the power change curve of each power supply unit based on the adjustment time, operating parameters and adjustment range.

[0062] Figure 4 and Figure 5 This is an optional schematic diagram of the power control system 100 provided in this embodiment of the disclosure. It should be noted that... Figure 4 and Figure 5 The grid-side meter 11 and load 40 can be understood with reference to the above embodiments, and will not be repeated here. Figure 5 In the inverters 1 to n, each can correspond to an electronic power supply unit. Figure 4 Each of the energy storage cabinets 1 to n in the power supply unit 30 can correspond to a power supply unit. Multiple power supply units in the power supply unit 30 can also be combinations of energy storage cabinets and photovoltaic solar panels. The photovoltaic power meter 331 is used to collect the output power of inverters 1 to n. The main control cabinet 320 is used to monitor and control the charging and discharging process of energy storage cabinets 1 to n. Figure 1 The power regulation unit 20 can be installed in the main control cabinet 320.

[0063] It should also be noted that since the reverse / over-demand adjustment process is carried out in real time based on the current system output power, load power, and grid-side power, further strategies are needed in the allocation method to reduce system losses. For example, when the state of charge (SOC) value and battery health value of any energy storage unit are low, and the battery temperature is high, the output efficiency of that energy storage unit is low. Dispatching its high-power generation will result in a large amount of waste and will accelerate battery damage.

[0064] In this embodiment of the disclosure, combined with Figure 1 and Figure 4The power regulation unit 20 can set the power change curve for each power supply unit based on the regulation time, operating parameters, and regulation amplitude. For example, when the power supply unit is an energy storage cabinet, the operating parameters include one or more of the following: battery state of charge (SOC), battery temperature, and battery state of health (SOH). The power regulation unit 20 can allocate different regulation amplitudes according to the operating parameters of each energy storage cabinet. Taking battery temperature as an example for the allocation of regulation amplitudes, the specific allocation ratios can be understood by referring to Table 1 below:

[0065] Battery temperature Allocation ratio Tmax > T battery > T average 30％ Tmin < T_battery ≤ T_avg 90％ T_battery = T_max 20％ T_battery = T_min 100％

[0066] Table 1

[0067] It should be noted that the power regulation unit 20 can allocate power ratios by setting the average temperature (Taverage), maximum temperature (Tmax), and minimum temperature (Tmin). The allocation ratio is the ratio of the regulation range of each energy storage unit to the total regulation range. Battery state of charge (SOC) and battery health (SOH) can be understood with reference to battery temperature, and will not be elaborated upon here.

[0068] In this embodiment of the disclosure, combined with Figure 1 and Figure 5 When the power supply unit is a photovoltaic solar panel, the operating parameters include one or more of the following: the number of photovoltaic modules, the number of channels at the maximum power point, and the illuminance. The number of photovoltaic modules, the number of channels at the maximum power point, and the illuminance can be understood by referring to the battery state of charge (SOC), battery temperature, and battery health (SOH) of the energy storage cabinet, respectively, and will not be elaborated here.

[0069] In some embodiments of this disclosure, the adjustment time is less than 2 seconds.

[0070] In this embodiment of the disclosure, reference is made to Figure 1 When the power generated by the power supply unit 30 exceeds the local load demand and there is a possibility of reverse current flowing into the power grid 10, if the reverse current regulation time is less than 2 seconds, it helps to maintain the voltage and frequency stability of the power grid 10 and avoid fluctuations in the power grid 10 caused by the reverse current. This protects the equipment in the power grid 10 from damage and extends its service life.

[0071] Figure 6 This is an optional flowchart illustrating the power control method provided in this embodiment of the disclosure, which will be combined with... Figure 6 The steps shown are explained. Figure 6 The method shown in the figure can be used by Figure 1 The power control system 100 shown is used to achieve this.

[0072] S101. Obtain the first grid-side power of the power grid, and determine whether there is reverse flow or over-demand based on the first grid-side power.

[0073] S102. In the event of reverse flow or over-demand, obtain the second grid-side power of the power grid and the output power of the power supply unit, and adjust the output power based on the second grid-side power; wherein the transmission delay of the second grid-side power is less than that of the first grid-side power.

[0074] In this embodiment of the disclosure, reference is made to Figure 1 The power regulation unit 20 can determine whether there is reverse current or over-demand based on the first grid-side power.

[0075] The process for identifying and handling backflow can be referenced. Figure 7 To understand each step:

[0076] S1101, Begin.

[0077] S1102, Detect grid-side power.

[0078] S1103, The power on the detection grid side exceeds the allowable value for reverse current.

[0079] S1104. Implement anti-backflow strategy.

[0080] In this embodiment of the disclosure, combined with Figure 1 and Figure 7 The power control unit 20 can detect the grid-side power of the power grid 10 (e.g., the first grid-side power). If it detects that the grid-side power of the power grid 10 exceeds the allowable reverse current range (i.e., the grid-side power is greater than the power value corresponding to the anti-reverse current control line), it immediately executes the anti-reverse current strategy. The execution process of the anti-reverse current strategy is described in [reference needed]. Figure 10 To understand the power change curve of the "countercurrent" section, we need to look at the curve. The power change curve is set based on the power of the second grid side.

[0081] The process for judging and handling excess demand can be referenced. Figure 8 To understand each step:

[0082] S2101, Begin.

[0083] S2102, Detect grid-side power.

[0084] S2103, The power on the detection network side exceeds the allowable value.

[0085] S2104. Implement the strategy to prevent over-demand.

[0086] In this embodiment of the disclosure, combined with Figure 1 and Figure 8The power control unit 20 can detect the grid-side power of the power grid 10 (e.g., the first grid-side power). If it finds that the grid-side power of the power grid 10 exceeds the reverse current allowable range (i.e., the grid-side power is less than the power value corresponding to the over-demand control line), it immediately executes the over-demand prevention strategy. The execution process of the over-demand prevention strategy is described in [reference needed]. Figure 10 We need to understand the power change curve in the "excess demand" section. The power change curve is set based on the power on the second grid side.

[0087] The callback judgment and handling process can be found in [reference]. Figure 9 To understand each step:

[0088] S3101, Begin.

[0089] S3102, Detect grid-side power.

[0090] S3103, The grid-side power was detected to be neither reversed nor exceeded.

[0091] S3104, Execute the callback strategy.

[0092] In this embodiment of the disclosure, combined with Figure 1 and Figure 9 The power control unit 20 can detect the grid-side power of the power grid 10 (e.g., the first grid-side power). If it finds that the grid-side power of the power grid 10 is neither reverse-current nor exceeds demand (i.e., the grid-side power is between the power values ​​corresponding to the anti-over-demand control line and the anti-reverse-current control line), it immediately executes the callback strategy. The execution process of the callback strategy is described in [reference needed]. Figure 10 We need to understand the power change curve in the "excess demand" section. The power change curve is set based on the power on the second grid side.

[0093] In this embodiment of the disclosure, reference is made to Figure 1 In energy storage scenarios (i.e., the power supply unit only includes the energy storage cabinet), the power regulation unit 20 can be configured according to... Figure 10 The scheme shown adjusts the output power of the energy storage cabinet. In a photovoltaic-energy storage scenario (i.e., the power supply unit only includes photovoltaic solar panels and an energy storage cabinet), since the energy storage anti-reverse current operation is faster than the photovoltaic anti-reverse current operation, the power regulation unit 20 can adjust the output power according to... Figure 11 The proposed solution prioritizes adjusting settings such as the energy storage cabinet. In photovoltaic application scenarios (i.e., the power supply unit consists only of photovoltaic solar panels), after maintaining a stable state for a period of time without reverse current or over-demand, the control method of the power control unit 20 can be referenced. Figure 10 This will be understood in more detail here.

[0094] In some embodiments of this disclosure, it can also be implemented via S201. Figure 6 Section S102 will be explained in conjunction with each step.

[0095] S201. Obtain the redundant power of the power grid, and determine the adjustment range of the output power based on the redundant power of the power grid and the power on the second grid side.

[0096] In this embodiment of the disclosure, reference is made to Figure 1 The power regulation unit 20 can determine the adjustment range of the output power based on the redundant power of the power grid and the second grid-side power. For example, in the presence of reverse current, the power regulation unit 20 can adjust the adjustment range of the output power of the power supply unit 30 to the difference between the excess power and the second grid-side power. In this way, the embodiments of this disclosure can reduce the adjustment range of the output power of the power supply unit 30 while avoiding the impact of reverse current and excess power on the normal operation of the power grid 10, thereby avoiding damage to the power supply unit 30.

[0097] In some embodiments of this disclosure, it can also be implemented via S301. Figure 6 Section S102 will be explained in conjunction with each step.

[0098] S103. Obtain the adjustment time and operating parameters of multiple power supply units, and set the power change curve of each power supply unit based on the adjustment time, operating parameters and adjustment range.

[0099] In this embodiment of the disclosure, reference is made to Figure 1 The power regulation unit 20 can adjust the power variation curve of each power supply unit according to operating parameters, adjustment range, and adjustment time. In this way, the adjustment range of each power supply unit can be matched to changes in operating parameters, thereby reducing system fluctuations and instability. This prevents the entire system from collapsing due to the failure or abnormality of a single unit.

[0100] The sequence numbers of the embodiments disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The methods disclosed in the several method embodiments provided in this disclosure can be arbitrarily combined to obtain new method embodiments without conflict. The features disclosed in the several product embodiments provided in this disclosure can be arbitrarily combined to obtain new product embodiments without conflict. The features disclosed in the several method or device embodiments provided in this disclosure can be arbitrarily combined to obtain new method embodiments or device embodiments without conflict.

[0101] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A power control system for preventing backflow and over-demand, characterized in that, include: Power regulation unit, power grid, power supply unit, first link and second link; among which, The power regulation unit is connected to the power grid and is configured to acquire a first grid-side power of the power grid and determine whether there is reverse current or over-demand based on the first grid-side power. The power regulation unit, connected to the power supply unit, is further configured to acquire the second grid-side power of the power grid and the output power of the power supply unit in the event of reverse current or over-demand, and to adjust the output power based on the second grid-side power; wherein the transmission delay of the second grid-side power is less than that of the first grid-side power. The power supply unit includes: multiple power supply units; The power regulation unit is connected to multiple power supply units and is also configured to acquire operating parameters of the multiple power supply units; the power regulation unit is connected to the power grid and the power supply unit through the first link and the second link; the transmission delay of the first link is less than that of the second link; the operating parameters, the output power and the second grid-side power are all transmitted through the first link; the first grid-side power is transmitted through the second link.

2. The power control system according to claim 1, characterized in that, The power regulation unit is configured to acquire the redundant power of the power grid and determine the adjustment range of the output power based on the redundant power of the power grid and the second grid-side power.

3. The power control system according to claim 2, characterized in that, The power regulation unit is further configured to acquire the regulation time and, based on the regulation time, the operating parameters, and the regulation amplitude, set a power change curve for each of the power supply units.

4. The power control system according to claim 2, characterized in that, The redundant power includes: excess power and reverse power; The power adjustment unit is configured to adjust the adjustment range to the difference between the reverse current power and the second grid-side power when reverse current exists; or, when there is excess demand, adjust the adjustment range to the difference between the excess demand power and the second grid-side power.

5. The power control system according to claim 3, characterized in that, The adjustment time is less than 2 seconds.

6. The power control system according to claim 3, characterized in that, The operating parameters include one or more of the following: battery state of charge, battery temperature, and battery health; and / or, the operating parameters include one or more of the following: number of photovoltaic modules, number of channels at maximum power point, and illuminance.

7. A power control method for preventing backflow and over-demand, characterized in that, include: Obtain the first grid-side power of the power grid, and determine whether there is reverse flow or over-demand based on the first grid-side power; In the event of reverse flow or over-demand, the second grid-side power of the power grid and the output power of the power supply unit are obtained, and the output power is adjusted based on the second grid-side power; wherein the transmission delay of the second grid-side power is less than that of the first grid-side power; The operating parameters of the multiple power supply units included in the power supply unit are obtained; wherein, the operating parameters of the multiple power supply units, the output power and the second network-side power are all transmitted through a first link; the first network-side power is transmitted through a second link, and the transmission delay of the first link is less than that of the second link.

8. The power control method according to claim 7, characterized in that, Adjusting the output power based on the second grid-side power includes: Obtain the redundant power of the power grid, and determine the adjustment range of the output power based on the redundant power of the power grid and the second grid-side power.

9. The power control method according to claim 8, characterized in that, The power control method further includes: The adjustment time is obtained, and based on the adjustment time, the operating parameters, and the adjustment range, the power change curve of each of the power supply units is set.

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