Control method of inverter hybrid parallel system and related equipment thereof

Abstract

The invention relates to the technical field of inverter control, and discloses a control method of an inverter hybrid parallel system and related equipment thereof, and the method comprises the steps: obtaining a target operation mode of the inverter hybrid parallel system based on an energy management system, a grid-connected inverter and an energy storage inverter in the inverter hybrid parallel system are arranged on an AC bus in parallel; the energy management system generates a grid-connected inverter output power given value and an energy storage inverter output power given value according to the acquired target operation mode, the power required by the load, the power of the grid-connected electric meter and the operation power of each device; and sending the output power given values of the inverters to the corresponding inverters through the energy management system, so that the grid-connected inverter and the energy storage inverter adjust the actual output power values of the grid-connected inverter and the energy storage inverter according to the corresponding output power given values. According to the method, the system-level operation mode control of the inverter hybrid parallel system is realized, and the inverter output power control effect is improved.

Description

Technical Field

[0001] The present application relates to the field of inverter control technology, and in particular to a control method for an inverter hybrid parallel system and related equipment. Background Art

[0002] With the advancement of photovoltaic inverter technology and the reduction of costs, household photovoltaic energy storage systems have gradually become one of the important ways to promote the green transformation of energy structure. However, with the iteration of technology and the increase in electricity consumption, the original inverters and energy storage batteries can no longer meet the current needs. Users usually use multiple machines in parallel to expand capacity and power.

[0003] Regarding the method of connecting multiple machines in parallel: First, due to the lack of communication between inverters when multiple machines are connected in parallel, it is impossible to control the system-level operating mode (such as different energy output priorities, grid-connected power limits, etc.), and the output power control effect of the inverter is poor, which affects the implementation of the multi-machine parallel system. Furthermore, when energy storage inverters and grid-connected inverters are connected in parallel, how to control the operating mode of the entire system to achieve the preset operating effect, improve user experience, increase user enthusiasm for purchasing additional photovoltaic systems, and promote the development of the photovoltaic industry is an urgent problem to be solved. For the above-mentioned problems in related technologies, no effective solution has been proposed so far. Summary of the invention

[0004] A control method for a hybrid parallel inverter system and related equipment provided in an embodiment of the present invention at least solve the problem in the related art that the hybrid parallel inverter system is difficult to achieve system-level operating mode control, the output power control effect of the inverter is poor, which affects the user experience and limits the promotion and application of the hybrid parallel system.

[0005] In order to solve the above problem, one aspect of an embodiment of the present invention provides a control method for a hybrid parallel inverter system, including: Acquiring a target operation mode of the hybrid parallel inverter system based on the energy management system; wherein the hybrid parallel inverter system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on an AC bus; Based on the target operation mode, the energy management system obtains the power required by the load, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system, and generates the grid-connected inverter output power given value and the energy storage inverter output power given value according to the target operation mode, the power required by the load, the grid-connected meter power and the operating power of each device; The grid-connected inverter output power set value is sent to the grid-connected inverter through the energy management system, and the energy storage inverter output power set value is sent to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set value.

[0006] In some of the embodiments, before the step of sending the grid-connected inverter output power set value to the grid-connected inverter through the energy management system, the method further includes: The grid-connected power threshold is obtained through the energy management system, and after the grid-connected inverter output power given value is generated, it is determined whether the grid-connected inverter output power given value is greater than the grid-connected power threshold; if so, the grid-connected power threshold is used as the updated grid-connected inverter output power given value.

[0007] In some embodiments, the steps of adjusting the actual output power values ​​of the grid-connected inverter and the energy storage inverter according to the corresponding output power given values ​​include: If the given value of the energy storage inverter output power is less than the actual value of the energy storage inverter output power, and / or the given value of the grid-connected inverter output power is less than the actual value of the grid-connected inverter output power, the inverter controls the corresponding photovoltaic modules to reduce the output power of the photovoltaic modules, so as to adjust the actual value of the inverter output power to the corresponding given value of the output power; If the given output power value of the energy storage inverter is greater than the actual output power value of the energy storage inverter, the energy storage inverter is used to control the corresponding photovoltaic modules to increase the output power of the photovoltaic modules and / or control the discharge of the energy storage battery; if the given output power value of the grid-connected inverter is greater than the actual output power value of the grid-connected inverter, the grid-connected inverter is used to control the corresponding photovoltaic modules to increase the output power of the photovoltaic modules and / or reduce the grid-connected power; so as to adjust the actual output power value of the corresponding inverter to the value closest to the corresponding output power given value.

[0008] In some of the embodiments, when the target operating mode is the self-generation and self-use mode, the energy transmission priority of the inverter hybrid parallel system is load, energy storage battery and power grid in sequence; when the target operating mode is the grid-connected priority mode, the energy transmission priority of the inverter hybrid parallel system is load, grid and energy storage battery in sequence; wherein, based on the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes: the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charge and discharge power of the energy storage battery, and the maximum charge and discharge power of the energy storage battery.

[0009] In some of the embodiments, when the target operation mode is a self-generation and self-use mode or a grid-connected priority mode, the method further includes: Obtaining the grid-connected power threshold, generating the output power intermediate given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively according to the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, as well as the power required by the load, the grid-connected electric meter power, the grid-connected power threshold and the operating power of each device, and sending the corresponding output power intermediate given values ​​to the corresponding grid-connected inverter and the energy storage inverter respectively, so that the grid-connected inverter and the energy storage inverter adjust the corresponding output power actual values ​​according to the output power intermediate given values; At the next set time, the load power required, grid-connected meter power, grid-connected power threshold and operating power of each device at the set time are obtained again, and the output power given values ​​corresponding to the grid-connected inverter and energy storage inverter are generated respectively in combination with the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode.

[0010] In some of the embodiments, when the target operating mode is the energy storage priority mode, the energy transmission priority of the inverter hybrid parallel system is load and grid, in sequence, and in the energy storage priority mode, the energy storage battery corresponding to the energy storage inverter does not perform a discharge operation; based on the energy output priority indicated by the energy storage priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charging power of the energy storage battery, and the maximum charging power of the energy storage battery.

[0011] In some embodiments, the inverter hybrid parallel system includes an energy storage inverter system composed of multiple energy storage inverters and a grid-connected inverter system composed of multiple grid-connected inverters, and the method further includes: Based on the energy management system, the grid-connected inverter output power set value is sent to the grid-connected inverter system, so that the grid-connected inverter system adjusts the output power actual value of each grid-connected inverter according to the grid-connected inverter output power set value; based on the energy management system, the energy storage inverter output power set value is sent to the energy storage inverter system, so that the energy storage inverter system adjusts the output power actual value of each energy storage inverter according to the energy storage inverter output power set value.

[0012] In order to solve the above problem, one aspect of an embodiment of the present invention provides a control device for a hybrid parallel inverter system, which is arranged in an energy management system, and includes: A target operation mode acquisition module is used to acquire a target operation mode of the hybrid parallel inverter system; wherein the hybrid parallel inverter system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; The output power given value generation module is used to obtain the load required power, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system based on the target operation mode, and generate the grid-connected inverter output power given value and the energy storage inverter output power given value according to the target operation mode, the load required power, the grid-connected meter power and the operating power of each device; The adjustment module is used to send the grid-connected inverter output power set value to the grid-connected inverter, and send the energy storage inverter output power set value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set value.

[0013] In some of the embodiments, the device also includes a grid-connected power limiting module, which is used to obtain a grid-connected power threshold and, after generating a grid-connected inverter output power given value, determine whether the grid-connected inverter output power given value is greater than the grid-connected power threshold; if so, the grid-connected power threshold is used as the updated grid-connected inverter output power given value.

[0014] In order to solve the above problems, one aspect of an embodiment of the present invention provides a photovoltaic inverter system, which includes an energy management system and an inverter hybrid parallel system; wherein: The inverter hybrid parallel system includes at least one grid-connected inverter and at least one energy storage inverter, both of which are used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; The energy management system is communicatively connected with each device in the hybrid parallel inverter system, and is used to obtain the target operating mode of the hybrid parallel inverter system, the power required by the load, the grid-connected meter power and the operating power of each device in the hybrid parallel inverter system, and generate a grid-connected inverter output power given value and an energy storage inverter output power given value according to the target operating mode, the power required by the load, the grid-connected meter power and the operating power of each device; and send the grid-connected inverter output power given value to the grid-connected inverter, and send the energy storage inverter output power given value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power given values.

[0015] The beneficial effects of the embodiments of the present invention are as follows: the target operation mode of the hybrid parallel inverter system is obtained by adopting an energy management system; wherein the hybrid parallel inverter system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; based on the target operation mode, the energy management system respectively obtains the power required by the load, the grid-connected meter power and the operating power of each device in the hybrid parallel inverter system, and generates the grid-connected inverter output according to the target operation mode, the power required by the load, the grid-connected meter power and the operating power of each device. Output power given value, energy storage inverter output power given value; send the grid-connected inverter output power given value to the grid-connected inverter through the energy management system, send the energy storage inverter output power given value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power given value. This overcomes the problem in the related technology that the inverter hybrid parallel system including the energy storage inverter and the grid-connected inverter is difficult to achieve system-level operation mode control, the inverter output power control effect is poor, the user experience is poor, and the user's enthusiasm for purchasing additional photovoltaic systems is limited, which limits the development of the photovoltaic industry. By communicating with each device in the inverter hybrid parallel system through the added energy management system, the output power of the energy storage inverter and the grid-connected inverter is given and controlled through the energy management system, the operation effect corresponding to the system-level operation mode is achieved, the user experience is improved, and the technical effect of the promotion and application of the inverter hybrid parallel system is expanded.

[0016] The details of one or more embodiments of the invention are set forth in the following drawings and description so that other features, objects, and advantages of the invention are more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other embodiments can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a flow chart of a control method of a hybrid parallel inverter system according to an embodiment of the present invention.

[0019] Figure 2 This is a connection diagram of various devices, power loads, and power grids in an energy management system and inverter hybrid parallel system according to another embodiment of the present invention.

[0020] Figure 3It is a schematic diagram of power control curves of various devices in a scenario where the grid-connected power is not limited in a self-generation and self-use mode of an embodiment of the present invention.

[0021] Figure 4 It is a schematic diagram of power control curves of various devices in the first grid-connected power threshold scenario in the self-generation and self-use mode of an embodiment of the present invention.

[0022] Figure 5 It is a schematic diagram of power control curves of various devices in the second grid-connected power threshold scenario in the self-generation and self-use mode of an embodiment of the present invention.

[0023] Figure 6 It is a schematic diagram of the framework of a control device for a hybrid parallel inverter system according to an embodiment of the present invention.

[0024] Figure 7 It is a schematic structural diagram of the electronic device of the present invention. DETAILED DESCRIPTION

[0025] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0026] In order to solve the above problems, an embodiment of the present invention provides a control method for a hybrid parallel inverter system, such as Figure 1 As shown, the control method of the inverter hybrid parallel system mainly includes: Step S101, obtaining a target operating mode of the inverter hybrid parallel system based on the energy management system; wherein the inverter hybrid parallel system includes at least one grid-connected inverter and at least one energy storage inverter, both the grid-connected inverter and the energy storage inverter are used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus.

[0027] In the inverter hybrid parallel system provided by the embodiment of the present invention, the energy storage inverter and the grid-connected inverter are multi-machine hybrid parallel. Figure 2As shown, the energy storage inverter is connected to the photovoltaic module, energy storage battery and AC bus. The photovoltaic module provides DC input to the energy storage inverter, which is converted by the energy storage inverter into AC output to the AC bus. The energy storage inverter can also use the electric energy of the energy storage battery as input and convert it into AC output to the AC bus. The photovoltaic module can also directly charge the battery through the energy storage machine DC bus. The energy storage inverter can also take the electric energy on the AC bus to charge the energy storage battery. The grid-connected inverter connects the photovoltaic module and the AC bus. The photovoltaic module provides DC input to the grid-connected inverter, which is converted by the grid-connected inverter into AC output to the AC bus. The grid-connected power of the AC bus is defined as the positive direction (that is, the power value indicated by the grid-connected meter is positive), and the power taken from the grid is defined as the negative direction (that is, the power value indicated by the grid-connected meter is negative).

[0028] The operation mode of the hybrid inverter parallel system indicates the energy output priority of the hybrid parallel system, that is, the energy obtained from the photovoltaic modules by the hybrid inverter system via the energy storage inverter and the grid-connected inverter is given priority to the load, the energy storage battery, and the power grid. It can be understood that according to the specific setting form of the operation mode, when the load has the highest energy output priority, if the energy provided by the photovoltaic modules is insufficient, the system can also obtain energy from the energy storage battery and the power grid to meet the power demand of the load.

[0029] The energy management system (EMS) provided in the embodiment of the present invention may be independently provided from the hybrid parallel inverter system, or may be integrated within the hybrid parallel inverter system.

[0030] Through the above settings, the energy management system is used as the central controller to first obtain the target operating mode of the inverter hybrid parallel system, provide guidance for subsequent power allocation and the data required to be obtained, and help ensure that the hybrid parallel system can operate according to the preset operating mode, thereby achieving the preset operating effect; by obtaining the target operating mode, the energy management system can also optimize the energy flow of the hybrid parallel system and improve the energy output efficiency of the hybrid parallel system. For example, when there is sufficient sunlight, photovoltaic power is used first, and when there is insufficient sunlight, it switches to energy storage batteries or grid power supply, so as to maximize the utilization of energy. In addition, users can also configure and monitor the operating status of the hybrid parallel system through the energy management system to further meet the power demand of user loads and improve user experience.

[0031] According to a specific implementation of an embodiment of the present invention, the above method further includes: introducing a machine learning algorithm to automatically select the optimal operation mode according to historical data and real-time environmental conditions. For example, by analyzing local weather forecast data, user load historical power consumption data to predict photovoltaic power generation, load power consumption prediction and other data, the target operation mode is dynamically adjusted to achieve intelligent energy management.

[0032] Step S102, based on the target operating mode, the energy management system obtains the power required by the load, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system, and generates a grid-connected inverter output power set value and an energy storage inverter output power set value according to the target operating mode, the power required by the load, the grid-connected meter power and the operating power of each device.

[0033] Through the above settings, according to the target operation mode, load demand and real-time operation power data of each device in the hybrid parallel system, the energy management system can dynamically adjust the output power of the grid-connected inverter and the energy storage inverter, while ensuring the power demand of the user's load, maximize the use of photovoltaic power, reduce dependence on the power grid, improve energy efficiency, and achieve accurate distribution and control of the inverter output power. Accurate power distribution helps to balance the energy flow of the system, reduce voltage fluctuations and frequency deviations, and improve the stability and reliability of the system. And by allocating power according to the power required by the load, the system can better respond to the user's power demand, provide a stable power supply, and improve the user experience.

[0034] According to a specific implementation of an embodiment of the present invention, during peak load power consumption periods, the energy storage inverter can also release the electric energy stored in the energy storage battery to reduce the burden on the power grid; during low load periods, the grid-connected inverter can transmit excess electric energy to the power grid to achieve peak shaving and valley filling and reduce electricity costs.

[0035] According to an embodiment of the present invention, the above method also includes: setting a fault detection and fault-tolerant control mechanism, performing fault detection on the energy storage inverter, the grid-connected inverter, and the photovoltaic module based on the energy management system, and when a certain inverter or photovoltaic module fails, the energy management system automatically adjusts the output power of other inverters (by setting the corresponding output power set value and sending the control signal corresponding to the value to the corresponding inverter) to ensure the continuous operation of the hybrid parallel system.

[0036] In some of the embodiments, before the step of sending the grid-connected inverter output power set value to the grid-connected inverter through the energy management system, the above method also includes: obtaining a grid-connected power threshold through the energy management system, and after generating the grid-connected inverter output power set value, determining whether the grid-connected inverter output power set value is greater than the grid-connected power threshold; if so, using the grid-connected power threshold as the updated grid-connected inverter output power set value.

[0037] Due to the requirements of the power grid, there are often certain restrictions on the grid-connected power of household energy storage systems. Therefore, while achieving the target operating mode, the grid-connected power limit (i.e. the above-mentioned grid-connected power threshold, which is determined according to the actual situation in each place) needs to be taken into consideration. The setting of the grid-connected power threshold can not only meet the requirements of the power grid, but also dynamically adjust the grid-connected power threshold in combination with the real-time grid status, weather conditions and load power demand. Furthermore, according to an embodiment of the present invention, a multi-level grid-connected power threshold can also be designed (a multi-level grid-connected power threshold refers to setting different thresholds according to different time periods or different working conditions).

[0038] Based on the above settings, after generating the given value of the grid-connected inverter output power, it is determined whether it is greater than the grid-connected power threshold, and when necessary, it is adjusted to the grid-connected power threshold, so that the grid-connected power of the hybrid parallel system does not exceed the limit specified by the power grid, which helps to avoid power outages or other problems caused by over-limit and ensure the safe operation of the hybrid parallel system. It can also reduce voltage fluctuations and frequency deviations, and improve the stability and reliability of the hybrid parallel system. At the same time, based on the above-mentioned grid-connected power limit, the energy storage inverter can release the energy in the energy storage battery to meet the load power demand, thereby maximizing the use of photovoltaic power, reducing dependence on the power grid, and improving the efficiency of green energy utilization.

[0039] In some of the embodiments, when the target operating mode is the self-generation and self-use mode, the energy transmission priority of the inverter hybrid parallel system is load, energy storage battery and power grid in sequence; when the target operating mode is the grid-connected priority mode, the energy transmission priority of the inverter hybrid parallel system is load, grid and energy storage battery in sequence; wherein, based on the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes: the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charge and discharge power of the energy storage battery, and the maximum charge and discharge power of the energy storage battery.

[0040] Among them, the inverter hybrid parallel system provided in the embodiment of the present invention is a household energy storage system, which needs to give priority to meeting the power demand of the user's load, so the highest priority of energy output in its operating mode is to supply power to the load. The difference between the self-generation and self-use mode and the grid-connected priority mode mainly lies in whether to supply power to the grid or to the energy storage battery first at the second priority. Therefore, based on the different operating modes, the specific objects of the operating power data of each device in the inverter hybrid parallel system obtained by the energy management system are slightly different.

[0041] By setting different operating modes and configuring different energy transmission priorities, the energy management system can reasonably allocate and utilize energy according to the target operating mode (spontaneous generation and self-use mode or grid-connected priority mode), thereby achieving a hybrid parallel system that balances energy flow, reduces voltage fluctuations and frequency deviations, and provides a more stable power supply. This improves the stability and reliability of the hybrid parallel system, enhances user experience, and helps maximize the use of photovoltaic power, reduce dependence on the power grid, and improve energy efficiency.

[0042] Specifically, according to a specific implementation of an embodiment of the present invention, in the self-generation and self-use mode, the hybrid parallel system gives priority to meeting the needs of local loads, and the excess power is stored in the energy storage battery before being transmitted to the power grid. This helps users save electricity bills and improve the self-sufficiency of the system. At the same time, in the grid-connected priority mode, the hybrid parallel system gives priority to meeting the needs of local loads, and then directly transmits the excess power to the power grid, and finally considers the energy storage battery. This helps users obtain more electricity sales revenue from the power grid company.

[0043] In some of the embodiments, when the target operating mode is the self-generation and self-use mode or the grid-connected priority mode, the method further includes: obtaining a grid-connected power threshold, generating output power intermediate given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively according to the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, as well as the load required power, the grid-connected meter power, the grid-connected power threshold and the operating power of each device, and sending the corresponding output power intermediate given values ​​to the corresponding grid-connected inverter and the energy storage inverter respectively, so that the grid-connected inverter and the energy storage inverter adjust the corresponding output power actual values ​​according to the output power intermediate given values; waiting for the next set time, obtaining the load required power, the grid-connected meter power, the grid-connected power threshold and the operating power of each device at the set time again, and generating the output power given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively in combination with the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode.

[0044] Taking into account the volatility of load power consumption, photovoltaic power generation and the limitation of grid-connected power threshold, the output power set value can be generated step by step, that is, by re-obtaining the load power required, grid-connected meter power, grid-connected power threshold and the operating power of each device at each set time, and generating a new output power set value based on these data. The energy management system realizes dynamic adjustment of the output power of the grid-connected inverter and the energy storage inverter, improves the real-time response capability of the hybrid parallel system, and improves the flexibility and adaptability of the hybrid parallel system, thereby achieving better control effect and preset operation effect.

[0045] According to a specific implementation of an embodiment of the present invention, in order to demonstrate the control effect of the embodiment of the present invention combined with grid-connected power limitation, as shown in FIG. Figure 3 , Figure 4 and Figure 5 Case simulation implementation examples of three scenarios are shown respectively: Scenario (1) Self-generation and self-use mode (no grid-connected power restriction); Scenario (2) Self-generation and self-use mode (grid-connected power restriction = 6000 W); Scenario (3) Self-generation and self-use mode (grid-connected power restriction = 0 W). At the same time, in this simulation implementation example, the rated output power of the energy storage inverter is set to 10kW, the energy storage battery capacity is set to 10 kW•h, the initial SOC of the energy storage battery is set to 100%, the maximum charging power of the energy storage battery is set to 5kW, and the maximum discharge power of the energy storage battery is set to 5 kW. The rated power of the grid-connected inverter is 10 kW. The power required by the load is a typical household power. The photovoltaic power generation is a typical sunny photovoltaic power generation power. Figure 3 , Figure 4 and Figure 5 It can be seen from the power control curve that the grid-connected power limitation strategy executed by the grid-connected power threshold can achieve the control effect of the system-level operation mode of the inverter hybrid parallel system, and at the same time implement the control of the grid-connected power limitation, which is helpful to improve the energy utilization efficiency.

[0046] In some of the embodiments, when the target operating mode is the energy storage priority mode, the energy transmission priority of the inverter hybrid parallel system is load and grid, in sequence, and in the energy storage priority mode, the energy storage battery corresponding to the energy storage inverter does not perform a discharge operation; based on the energy output priority indicated by the energy storage priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charging power of the energy storage battery, and the maximum charging power of the energy storage battery.

[0047] Adopting the energy storage priority mode helps protect the energy storage battery and avoid shortening the battery life due to over-discharge. In this mode, the energy storage battery discharge operation does not need to be considered, so the current discharge power and maximum discharge power of the energy storage battery do not need to be obtained; it is only necessary to generate the corresponding output power given value while meeting the load power demand and grid-connected power limit.

[0048] Step S103, sending the grid-connected inverter output power set value to the grid-connected inverter through the energy management system, and sending the energy storage inverter output power set value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set values.

[0049] The output power setpoints of the grid-connected inverter and the energy storage inverter are sent to the corresponding inverters through the energy management system, ensuring that each inverter can adjust its actual output power according to the precise power command, which improves the output power control accuracy of the inverter and enables the hybrid parallel system to more accurately meet the requirements of the target operation mode. Through precise power control, the system can balance the energy flow, reduce voltage fluctuations and frequency deviations, and improve the stability and reliability of the system.

[0050] In some of the embodiments, the step of adjusting the respective actual output power values ​​of the grid-connected inverter and the energy storage inverter according to the corresponding output power given value includes: if the output power given value of the energy storage inverter is less than the actual output power value of the energy storage inverter, and / or the output power given value of the grid-connected inverter is less than the actual output power value of the grid-connected inverter, then controlling the corresponding photovoltaic assembly by the inverter to reduce the output power of the photovoltaic assembly, so as to adjust the actual output power value of the inverter to the corresponding output power given value; if the output power given value of the energy storage inverter is greater than the actual output power value of the energy storage inverter, then controlling the corresponding photovoltaic assembly by the energy storage inverter to increase the output power of the photovoltaic assembly and / or control the discharge of the energy storage battery; if the output power given value of the grid-connected inverter is greater than the actual output power value of the grid-connected inverter, then controlling the corresponding photovoltaic assembly by the grid-connected inverter to increase the output power of the photovoltaic assembly and / or reduce the grid-connected power; so as to adjust the actual output power value of the corresponding inverter to a value closest to the corresponding output power given value.

[0051] By comparing the output power set value with the actual value in real time, the hybrid parallel system can accurately adjust the energy flow between photovoltaic panels, energy storage batteries and the power grid, so that the power output of the hybrid parallel system is highly consistent with the target operating mode, thereby improving the control accuracy of the hybrid parallel system.

[0052] Specifically, when the given value of the energy storage inverter output power is less than the actual value: by reducing the output power of the photovoltaic module, the energy entering the energy storage inverter can be reduced, so that the actual value of its output power is reduced to the given value. This helps prevent the energy storage battery from overcharging, prolongs the battery life, and improves the reliability and stability of the system.

[0053] When the grid-connected inverter output power given value is less than the actual value: By reducing the output power of the PV modules, the energy entering the grid-connected inverter can be reduced, so that the actual output power value is reduced to the given value. This helps to ensure that the grid-connected power does not exceed the limit specified by the power grid, avoid over-limit problems, and improve the safety of the system.

[0054] When the given value of the energy storage inverter output power is greater than the actual value: By increasing the output power of the photovoltaic module, the energy entering the energy storage inverter can be increased, so that the actual value of its output power increases to the given value. If the output power of the photovoltaic module is not enough to reach the given value, the energy can be supplemented by controlling the discharge of the energy storage battery to meet the given value. This helps to ensure that the output power of the energy storage inverter reaches the given value, meet the energy needs of the system, and improve the response speed and flexibility of the system.

[0055] When the grid-connected inverter output power set value is greater than the actual value: By increasing the output power of the PV module, the energy entering the grid-connected inverter can be increased, so that its actual output power value increases to the set value. If the output power of the PV module is not enough to reach the set value, the energy flow of the system can be balanced by reducing the grid-connected power to meet the set value. This helps to ensure that the output power of the grid-connected inverter reaches the set value, meets the energy demand of the system, and maintains the stability of the system.

[0056] It should be noted that since the total energy output of the inverter hybrid parallel system is affected by the photovoltaic power generation state, the energy storage battery state and the power grid state, the above-mentioned adjustment of the actual output power value of the inverter to the given output power value is not achievable under all working conditions. In this state, it is only necessary to adjust the actual output power value of the inverter to the value closest to the given output power value. At this time, the operating effect preset by the target operating mode can be achieved to the greatest extent.

[0057] In some of the embodiments, the inverter hybrid parallel system includes an energy storage inverter system composed of multiple energy storage inverters and a grid-connected inverter system composed of multiple grid-connected inverters. The above method also includes: based on the energy management system, sending the grid-connected inverter output power set value to the grid-connected inverter system, so that the grid-connected inverter system adjusts the output power actual value of each grid-connected inverter according to the grid-connected inverter output power set value; based on the energy management system, sending the energy storage inverter output power set value to the energy storage inverter system, so that the energy storage inverter system adjusts the output power actual value of each energy storage inverter according to the energy storage inverter output power set value.

[0058] The above steps provide another control strategy for the hybrid parallel inverter system, that is, introducing the concepts of main system and subsystem, constructing an energy storage inverter system based on multiple energy storage inverters in the hybrid parallel inverter system, and constructing a grid-connected inverter system based on multiple grid-connected inverters in the hybrid parallel inverter system. Among them, both subsystems (energy storage inverter system and grid-connected inverter system) establish communication with the energy management system to adjust the actual output power value of the inverter in each system in response to the output power given value sent by the energy management system. This ensures the overall coordination and consistency of the system and avoids the control inconsistency problem caused by lack of communication when multiple machines are connected in parallel.

[0059] At the same time, the energy storage inverter system or the grid-connected inverter system can make more reasonable energy distribution for all energy storage inverters or all grid-connected inverters in the system according to the given value of the output power of the energy storage inverter or the given value of the output power of the grid-connected inverter. This helps to maximize the use of photovoltaic power, reduce dependence on the grid, and improve energy utilization efficiency. Through the centralized control of the energy management system, the energy flow of the system can be balanced, voltage fluctuations and frequency deviations can be reduced, and the stability and reliability of the system can be improved. This helps to provide a more stable power supply and improve user experience. The subsystem (energy storage inverter system, grid-connected inverter system) can ensure that the grid-connected power of the main system (inverter hybrid parallel system) does not exceed the limit specified by the grid (such as the grid-connected power threshold) according to the grid-connected meter power and the target operation mode, avoiding power outages or other problems caused by over-limit. This helps to ensure that the inverter hybrid parallel system achieves efficient, stable and reliable operation and meets the needs of various application scenarios.

[0060] The control method of the hybrid inverter parallel system provided in the embodiment of the present invention obtains the target operation mode of the hybrid inverter parallel system by adopting an energy management system; wherein the hybrid inverter parallel system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; based on the target operation mode, the energy management system respectively obtains the power required by the load, the grid-connected meter power and the operating power of each device in the hybrid inverter parallel system, and obtains the target operation mode, the power required by the load, the grid-connected meter power and the operating power of each device according to the target operation mode. The grid-connected inverter output power given value and the energy storage inverter output power given value are generated by the energy management system; the grid-connected inverter output power given value is sent to the grid-connected inverter through the energy management system, and the energy storage inverter output power given value is sent to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power given value. The technical means overcomes the problem that the inverter hybrid parallel system including the energy storage inverter and the grid-connected inverter in the related technology is difficult to achieve system-level operation mode control, the inverter output power control effect is poor, the user experience is poor, and the user's enthusiasm for purchasing additional photovoltaic systems is limited, which limits the development of the photovoltaic industry. By communicating with each device in the inverter hybrid parallel system through the added energy management system, the output power of the energy storage inverter and the grid-connected inverter is given and controlled through the energy management system, the operation effect corresponding to the system-level operation mode is achieved, the user experience is improved, and the technical effect of promoting the application of the inverter hybrid parallel system is expanded.

[0061] Based on the control method of the hybrid inverter parallel system provided by the embodiment of the present invention, the embodiment of the present invention also provides a control device of the hybrid inverter parallel system, which is applied to an energy management system. The energy management system can be set independently of the hybrid inverter parallel system or integrated inside the hybrid inverter parallel system. Figure 6 As shown, the control device 600 of the inverter hybrid parallel system includes: The target operation mode acquisition module 601 is used to acquire the target operation mode of the hybrid parallel inverter system; wherein the hybrid parallel inverter system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus.

[0062] Through the above settings, the energy management system is used as the central controller to first obtain the target operating mode of the inverter hybrid parallel system, provide guidance for subsequent power allocation and the data required to be obtained, and help ensure that the hybrid parallel system can operate according to the preset operating mode, thereby achieving the preset operating effect; by obtaining the target operating mode, the energy management system can also optimize the energy flow of the hybrid parallel system and improve the energy output efficiency of the hybrid parallel system. For example, when there is sufficient sunlight, photovoltaic power is used first, and when there is insufficient sunlight, it switches to energy storage batteries or grid power supply, so as to maximize the utilization of energy. In addition, users can also configure and monitor the operating status of the hybrid parallel system through the energy management system to further meet the power demand of user loads and improve user experience.

[0063] The output power set value generation module 602 is used to obtain the load required power, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system based on the target operating mode, and generate the grid-connected inverter output power set value and the energy storage inverter output power set value according to the target operating mode, the load required power, the grid-connected meter power and the operating power of each device.

[0064] Through the above settings, according to the target operation mode, load demand and real-time operation power data of each device in the hybrid parallel system, the energy management system can dynamically adjust the output power of the grid-connected inverter and the energy storage inverter, while ensuring the power demand of the user's load, maximize the use of photovoltaic power, reduce dependence on the power grid, improve energy efficiency, and achieve accurate distribution and control of the inverter output power. Accurate power distribution helps to balance the energy flow of the system, reduce voltage fluctuations and frequency deviations, and improve the stability and reliability of the system. And by allocating power according to the power required by the load, the system can better respond to the user's power demand, provide a stable power supply, and improve the user experience.

[0065] In some of the embodiments, the control device 600 of the above-mentioned inverter hybrid parallel system also includes a grid-connected power limiting module, which is used to obtain a grid-connected power threshold, and after generating a grid-connected inverter output power given value, determine whether the grid-connected inverter output power given value is greater than the grid-connected power threshold; if so, the grid-connected power threshold is used as the updated grid-connected inverter output power given value.

[0066] Based on the above settings, after generating the grid-connected inverter output power given value, it is determined whether it is greater than the grid-connected power threshold, and when necessary, it is adjusted to the grid-connected power threshold, so that the grid-connected power of the hybrid parallel system does not exceed the limit specified by the power grid, which helps to avoid power outages or other problems caused by over-limit and ensure the safe operation of the hybrid parallel system. It can also reduce voltage fluctuations and frequency deviations, and improve the stability and reliability of the hybrid parallel system.

[0067] In some of the embodiments, when the target operating mode is the self-generation and self-use mode, the energy transmission priority of the inverter hybrid parallel system is load, energy storage battery and power grid in sequence; when the target operating mode is the grid-connected priority mode, the energy transmission priority of the inverter hybrid parallel system is load, grid and energy storage battery in sequence; wherein, based on the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes: the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charge and discharge power of the energy storage battery, and the maximum charge and discharge power of the energy storage battery.

[0068] By setting different operating modes and configuring different energy transmission priorities, the energy management system can reasonably allocate and utilize energy according to the target operating mode (spontaneous generation and self-use mode or grid-connected priority mode), thereby achieving a hybrid parallel system that balances energy flow, reduces voltage fluctuations and frequency deviations, and provides a more stable power supply. This improves the stability and reliability of the hybrid parallel system, enhances user experience, and helps maximize the use of photovoltaic power, reduce dependence on the power grid, and improve energy efficiency.

[0069] In some of the embodiments, when the target operating mode is the self-generation and self-use mode or the grid-connected priority mode, the method further includes: obtaining a grid-connected power threshold, generating output power intermediate given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively according to the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, as well as the load required power, the grid-connected meter power, the grid-connected power threshold and the operating power of each device, and sending the corresponding output power intermediate given values ​​to the corresponding grid-connected inverter and the energy storage inverter respectively, so that the grid-connected inverter and the energy storage inverter adjust the corresponding output power actual values ​​according to the output power intermediate given values; waiting for the next set time, obtaining the load required power, the grid-connected meter power, the grid-connected power threshold and the operating power of each device at the set time again, and generating the output power given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively in combination with the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode.

[0070] By re-obtaining the load power required, grid-connected meter power, grid-connected power threshold and operating power of each device at each set moment, and generating new output power setpoints based on these data, the energy management system can dynamically adjust the output power of the grid-connected inverter and energy storage inverter, improve the real-time response capability of the hybrid parallel system, and improve the flexibility and adaptability of the hybrid parallel system, thereby achieving better control effects and preset operating effects.

[0071] In some of the embodiments, when the target operating mode is the energy storage priority mode, the energy transmission priority of the inverter hybrid parallel system is load and grid, in sequence, and in the energy storage priority mode, the energy storage battery corresponding to the energy storage inverter does not perform a discharge operation; based on the energy output priority indicated by the energy storage priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charging power of the energy storage battery, and the maximum charging power of the energy storage battery.

[0072] In the energy storage priority mode, there is no need to consider the discharge operation of the energy storage battery, so the current discharge power and maximum discharge power of the energy storage battery do not need to be obtained; it is only necessary to generate the corresponding output power given value while meeting the load power demand and the grid power limit.

[0073] The adjustment module 603 is used to send the grid-connected inverter output power set value to the grid-connected inverter, and send the energy storage inverter output power set value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set values.

[0074] The output power setpoints of the grid-connected inverter and the energy storage inverter are sent to the corresponding inverters through the energy management system, ensuring that each inverter can adjust its actual output power according to precise power instructions. This improves the output power control accuracy of the inverter and enables the hybrid parallel system to more accurately meet the requirements of the target operating mode.

[0075] In some of the embodiments, the adjustment module 603 is further used for: if the output power given value of the energy storage inverter is less than the actual output power value of the energy storage inverter, and / or the output power given value of the grid-connected inverter is less than the actual output power value of the grid-connected inverter, then the inverter is used to control the corresponding photovoltaic assembly to reduce the output power of the photovoltaic assembly, so as to adjust the actual output power value of the inverter to the corresponding output power given value; if the output power given value of the energy storage inverter is greater than the actual output power value of the energy storage inverter, then the energy storage inverter is used to control the corresponding photovoltaic assembly to increase the output power of the photovoltaic assembly and / or control the discharge of the energy storage battery; if the output power given value of the grid-connected inverter is greater than the actual output power value of the grid-connected inverter, then the grid-connected inverter is used to control the corresponding photovoltaic assembly to increase the output power of the photovoltaic assembly and / or reduce the grid-connected power; so as to adjust the actual output power value of the corresponding inverter to a value closest to the corresponding output power given value.

[0076] By comparing the output power set value with the actual value in real time, the hybrid parallel system can accurately adjust the energy flow between photovoltaic panels, energy storage batteries and the power grid, so that the power output of the hybrid parallel system is highly consistent with the target operating mode, thereby improving the control accuracy of the hybrid parallel system.

[0077] The control device of the hybrid inverter parallel system provided by the embodiment of the present invention obtains the target operating mode of the hybrid inverter parallel system through the target operating mode acquisition module; wherein the hybrid inverter parallel system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; the output power set value generation module obtains the load required power, the grid-connected meter power and the operating power of each device in the hybrid inverter parallel system based on the target operating mode, and generates the grid-connected inverter output power set value and the energy storage inverter output power set value according to the target operating mode, the load required power, the grid-connected meter power and the operating power of each device; the grid-connected inverter output power set value is sent to the grid-connected inverter through the adjustment module, and the energy storage inverter output power set value is sent to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set values. The invention overcomes the problem in the related art that the hybrid parallel inverter system including energy storage inverter and grid-connected inverter is difficult to realize system-level operation mode control, the output power control effect of the inverter is poor, the user experience is poor, and the enthusiasm of users to purchase additional photovoltaic systems is limited, which limits the development of the photovoltaic industry. By communicating with each device in the hybrid parallel inverter system through the added energy management system, the output power of the energy storage inverter and the grid-connected inverter can be given control through the energy management system, the operation effect corresponding to the system-level operation mode is realized, the user experience is improved, and the technical effect of promoting the application of the hybrid parallel inverter system is expanded.

[0078] An embodiment of the present invention also provides a photovoltaic inverter system, which includes an energy management system and an inverter hybrid parallel system; wherein the inverter hybrid parallel system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on the AC bus; the energy management system is communicated with each device in the inverter hybrid parallel system, and is used to obtain a target operating mode of the inverter hybrid parallel system, obtain the power required by the load, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system, and generate a grid-connected inverter output power given value and an energy storage inverter output power given value according to the target operating mode, the power required by the load, the grid-connected meter power and the operating power of each device; and the grid-connected inverter output power given value is sent to the grid-connected inverter, and the energy storage inverter output power given value is sent to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power given values.

[0079] An embodiment of the present invention further provides a non-transitory machine-readable medium storing a computer program, wherein the computer program, when executed by a processor of a computer, is used to cause the computer to execute the method of the embodiment of the present invention.

[0080] The embodiment of the present invention further provides a computer program product, including a computer program, wherein the computer program is used to make the computer perform the method of the embodiment of the present invention when executed by a processor of the computer. The computer program product should be understood as a software product that mainly implements the above method of the present application through a computer program.

[0081] An embodiment of the present invention further provides an electronic device, comprising: at least one processor; and a memory in communication with the at least one processor. The memory stores a computer program executable by the at least one processor, and when the computer program is executed by the at least one processor, the electronic device executes the method of the embodiment of the present invention.

[0082] refer to Figure 7, a block diagram of an electronic device that can be used as a server or client of an embodiment of the present invention will now be described, which is an example of a hardware device that can be applied to various aspects of the present invention. The electronic device is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0083] like Figure 7 As shown, the electronic device includes a computing unit 701, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 702 or a computer program loaded from a storage unit 708 to a random access memory (RAM) 703. In the RAM 703, various programs and data required for the operation of the electronic device can also be stored. The computing unit 701, the ROM 702, and the RAM 703 are connected to each other via a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0084] Multiple components in the electronic device are connected to the I / O interface 705, including: an input unit 706, an output unit 707, a storage unit 708, and a communication unit 709. The input unit 706 can be any type of device that can input information to the electronic device, and the input unit 706 can receive input digital or character information, and generate key signal input related to user settings and / or function control of the electronic device. The output unit 707 can be any type of device that can present information, and can include but is not limited to a display, a speaker, a video / audio output terminal, a vibrator, and / or a printer. The storage unit 708 can include but is not limited to a disk, an optical disk. The communication unit 709 allows the electronic device to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks, and can include but is not limited to a modem, a network card, an infrared communication device, and / or a wireless communication transceiver, such as a Bluetooth device, a WiFi device, a WiMax device, a cellular communication device, and / or the like.

[0085] The computing unit 701 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 701 include, but are not limited to, a CPU, a graphics processing unit (GPU), various special artificial intelligence (AI) computing units, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit 701 performs the various methods and processes described above. For example, in some embodiments, the method embodiments of the present invention may be implemented as a computer program, which is tangibly contained in a machine-readable medium, such as a storage unit 708. In some embodiments, part or all of the computer program may be loaded and / or installed on an electronic device via a ROM 702 and / or a communication unit 709. In some embodiments, the computing unit 701 may be configured to perform the above-described method in any other appropriate manner (e.g., by means of firmware).

[0086] The computer programs for implementing the methods of the embodiments of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer programs are executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer programs may be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0087] In the context of an embodiment of the present invention, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or apparatus. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable signal medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, or infrared systems, devices, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media may include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0088] It should be noted that the term "including" and its variations used in the embodiments of the present invention are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "multiple" mentioned in the embodiments of the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0089] The information (including but not limited to device information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the embodiments of the present invention are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of relevant countries and regions, and corresponding operation entrances are provided for users to choose to authorize or refuse.

[0090] The various steps described in the method implementation methods provided in the embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method implementation methods may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0091] The term "embodiment" in this specification refers to specific features, structures or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. The various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments refer to each other. In particular, for the device, equipment, and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts refer to the partial description of the method embodiment.

[0092] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of protection. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A control method for a hybrid parallel inverter system, characterized in that: include: Acquiring a target operation mode of the hybrid parallel inverter system based on the energy management system; wherein the hybrid parallel inverter system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on an AC bus; Based on the target operation mode, the energy management system obtains the power required by the load, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system, and generates a grid-connected inverter output power given value and an energy storage inverter output power given value according to the target operation mode, the power required by the load, the grid-connected meter power and the operating power of each device; The energy management system sends the grid-connected inverter output power set value to the grid-connected inverter, and sends the energy storage inverter output power set value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set values.

2. The method according to claim 1, characterized in that Before the step of sending the grid-connected inverter output power set value to the grid-connected inverter through the energy management system, the method further includes: The grid-connected power threshold is obtained through the energy management system, and after the grid-connected inverter output power given value is generated, it is determined whether the grid-connected inverter output power given value is greater than the grid-connected power threshold; if so, the grid-connected power threshold is used as the updated grid-connected inverter output power given value.

3. The method according to claim 1, characterized in that The step of adjusting the respective actual output power values ​​of the grid-connected inverter and the energy storage inverter according to the corresponding output power given values ​​comprises: If the output power setting value of the energy storage inverter is less than the actual output power value of the energy storage inverter, and / or the output power setting value of the grid-connected inverter is less than the actual output power value of the grid-connected inverter, the inverter controls the corresponding photovoltaic module to reduce the output power of the photovoltaic module, so as to adjust the actual output power value of the inverter to the corresponding output power setting value; If the output power given value of the energy storage inverter is greater than the actual output power value of the energy storage inverter, the energy storage inverter is used to control the corresponding photovoltaic components to increase the output power of the photovoltaic components and / or control the discharge of the energy storage battery; if the output power given value of the grid-connected inverter is greater than the actual output power value of the grid-connected inverter, the grid-connected inverter is used to control the corresponding photovoltaic components to increase the output power of the photovoltaic components and / or reduce the grid-connected power; so as to adjust the actual output power value of the corresponding inverter to a value closest to the corresponding output power given value.

4. The method according to claim 1, characterized in that: When the target operation mode is the self-generation and self-use mode, the energy transmission priorities of the inverter hybrid parallel system are load, energy storage battery and power grid in sequence; when the target operation mode is the grid-connected priority mode, the energy transmission priorities of the inverter hybrid parallel system are load, power grid and energy storage battery in sequence; wherein, based on the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes: the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charge and discharge power of the energy storage battery and the maximum charge and discharge power of the energy storage battery.

5. The method according to claim 4, characterized in that When the target operation mode is the self-generation and self-use mode or the grid-connection priority mode, the method further includes: Obtaining a grid-connected power threshold, generating output power intermediate given values ​​corresponding to the grid-connected inverter and the energy storage inverter respectively according to the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode, the power required by the load, the grid-connected electric meter power, the grid-connected power threshold and the operating power of each device, and sending the corresponding output power intermediate given values ​​to the corresponding grid-connected inverter and energy storage inverter respectively, so that the grid-connected inverter and the energy storage inverter adjust the corresponding output power actual values ​​according to the output power intermediate given values; At the next set time, the load required power, grid-connected meter power, grid-connected power threshold and operating power of each device at the set time are obtained again, and the output power set values ​​corresponding to the grid-connected inverter and the energy storage inverter are generated respectively in combination with the energy output priority indicated by the self-generation and self-use mode or the grid-connected priority mode.

6. The method according to claim 4, characterized in that When the target operation mode is the energy storage priority mode, the energy transmission priority of the inverter hybrid parallel system is load and grid in sequence, and in the energy storage priority mode, the energy storage battery corresponding to the energy storage inverter does not perform a discharge operation; Based on the energy output priority indicated by the energy storage priority mode, the operating power of each device in the inverter hybrid parallel system obtained by the energy management system includes the output power of the energy storage inverter, the output power of the grid-connected inverter, the output power of the photovoltaic module, the maximum output power of the photovoltaic module, the SOC of the energy storage battery, the charging power of the energy storage battery and the maximum charging power of the energy storage battery.

7. The method according to claim 1, characterized in that The inverter hybrid parallel system includes an energy storage inverter system composed of a plurality of the energy storage inverters and a grid-connected inverter system composed of a plurality of the grid-connected inverters, and the method further includes: Based on the energy management system, the grid-connected inverter output power set value is sent to the grid-connected inverter system, so that the grid-connected inverter system adjusts the output power actual value of each of the grid-connected inverters according to the grid-connected inverter output power set value; based on the energy management system, the energy storage inverter output power set value is sent to the energy storage inverter system, so that the energy storage inverter system adjusts the output power actual value of each of the energy storage inverters according to the energy storage inverter output power set value.

8. A control device for a hybrid parallel inverter system, characterized in that: Set in an energy management system, the device includes: A target operation mode acquisition module, used to acquire a target operation mode of an inverter hybrid parallel system; wherein the inverter hybrid parallel system includes at least one grid-connected inverter and at least one energy storage inverter, the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on an AC bus; An output power set value generation module is used to obtain the load required power, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system based on the target operation mode, and generate a grid-connected inverter output power set value and an energy storage inverter output power set value according to the target operation mode, the load required power, the grid-connected meter power and the operating power of each device; An adjustment module is used to send the output power set value of the grid-connected inverter to the grid-connected inverter, and send the output power set value of the energy storage inverter to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power set values.

9. The device according to claim 8, characterized in that The device also includes a grid-connected power limiting module, which is used to obtain a grid-connected power threshold and, after generating the grid-connected inverter output power given value, determine whether the grid-connected inverter output power given value is greater than the grid-connected power threshold; if so, use the grid-connected power threshold as the updated grid-connected inverter output power given value.

10. A photovoltaic inverter system, characterized in that: The system includes an energy management system and an inverter hybrid parallel system; wherein, The inverter hybrid parallel system includes at least one grid-connected inverter and at least one energy storage inverter, wherein the grid-connected inverter and the energy storage inverter are both used to connect photovoltaic modules, and the grid-connected inverter and the energy storage inverter are arranged in parallel on an AC busbar; The energy management system is communicatively connected with each device in the inverter hybrid parallel system, and is used to obtain the target operating mode of the inverter hybrid parallel system, obtain the load required power, the grid-connected meter power and the operating power of each device in the inverter hybrid parallel system, and generate a grid-connected inverter output power given value and an energy storage inverter output power given value according to the target operating mode, the load required power, the grid-connected meter power and the operating power of each device; and send the grid-connected inverter output power given value to the grid-connected inverter, and send the energy storage inverter output power given value to the energy storage inverter, so that the grid-connected inverter and the energy storage inverter adjust their respective output power actual values ​​according to the corresponding output power given values.

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