A DC coupled optical storage system and communication control method

Abstract

The disclosed embodiment relates to the field of photovoltaic storage power generation technology, and discloses a DC-coupled photovoltaic storage system and a communication control method, wherein the system includes: a coordination controller, a GOOSE network switch, an MMS network switch, an inverter module DC / AC, an optical fiber terminal box, an energy management system, a photovoltaic system, an energy storage system, and a dispatching system; the photovoltaic system and the energy storage system are connected to the DC side of the inverter module; the first end of the GOOSE network switch is connected to the energy storage system, the photovoltaic system, and the inverter module DC / AC, and the second end of the GOOSE network switch is connected to the first end of the coordination controller; the first end of the MMS network switch is connected to the first end of the inverter module DC / AC, the energy storage system, and the energy management system; the second end of the MMS network switch is connected to the first end of the optical fiber terminal box; and the second end of the energy management system is connected to the photovoltaic system. In an exemplary embodiment of the present disclosure, the coordination controller can flexibly adjust the output threshold of the photovoltaic storage system according to the real-time output of the inverter module.

Description

Technical Field

[0001] The disclosed embodiments relate to the technical field of photovoltaic power generation, and more particularly to a DC-coupled photovoltaic power generation system in a DC / DC coupled mode and a communication control method. Background Art

[0002] At present, the communication control method of DC-side coupled DC-coupled photovoltaic storage system with energy storage DC / DC is relatively simple, such as Figure 1 As shown, the communication control is collected and controlled by the battery management system (BMS), energy management system (EMU), and data acquisition device (EMS). Specifically, when transmitting upward: first, the BMS collects all battery information and transmits it to the EMU, and the EMU collects BMS information, energy storage DC / DC information, energy storage meter information and other information and uploads it to the EMS, and the EMS collects EMU information, inverter module (DC / AC) information, box transformer low-voltage side information, etc. for upward transmission; when controlling downward: first, the dispatcher sends the information to the EMS, and the EMS sends instructions to the EMU by comparing the power size, and the EMU controls the charging and discharging of the energy storage battery, and the EMS controls the inverter module to control the photovoltaic output at the same time. The existing technology has the following disadvantages: Long response time: When EMS directly collects the equipment information of each photovoltaic power generation unit in the station, the huge amount of data will put forward higher requirements on the hardware performance and software control capabilities of EMS. Since a set of control systems needs to control dozens or even hundreds of inverter modules DC / AC and energy storage DC / DC to run simultaneously, the overall closed-loop operation time from data collection (including protocol conversion), logical judgment, command issuance to on-site response will be as long as tens of seconds, and the advantage of rapid regulation of energy storage cannot be brought into play. Poor control accuracy: Since the information of photovoltaic and energy storage is collected separately, and then the inverter output and energy storage charging and discharging are controlled separately, the time for uploading and regulating the two parts of information is different. From the perspective of the overall output of the photovoltaic power generation unit, the coordination consistency of photovoltaic power generation and energy storage charging and discharging is poor, resulting in large fluctuations in the output of the photovoltaic power generation unit. Single control mode: The existing AGC / AVC system at the station control layer can only use the rated capacity of the box transformer of each photovoltaic power generation unit as the maximum control power of the power generation unit grid connection point, and the output threshold is fixed. The maximum output threshold of the daily grid connection point cannot be adjusted dynamically according to the actual weather, resulting in low energy storage utilization in cloudy weather and energy storage not working in rainy weather. At the same time, the output threshold issued by the existing AGC / AVC only considers photovoltaic output and does not consider the role of energy storage, making the utilization rate of energy storage even lower in actual operation.

[0003] In summary, the existing DC-coupled solar-storage system uses the energy storage BMS to collect battery information and upload it to the EMU, which uploads the information to the EMS, which uploads the information to the dispatcher; the dispatcher sends the information to the EMS, which sends instructions step by step to control the battery charging and discharging. This control method has slow response, many links, and is prone to failure. When problems occur during the operation of the solar-storage system, it is impossible to quickly find the problematic link for maintenance, nor can it intuitively adjust the control systems at all levels. Summary of the invention

[0004] The embodiments of the present disclosure provide a DC-coupled photovoltaic storage system and a communication control method to solve or alleviate one or more of the above technical problems in the prior art.

[0005] According to one aspect of the present disclosure, there is provided a DC-coupled photovoltaic storage system, comprising: a coordination controller, a GOOSE network switch, an MMS network switch, an inverter module DC / AC, an optical fiber terminal box, an energy management system, a photovoltaic system, an energy storage system, and a dispatching system;

[0006] The photovoltaic system and the energy storage system are connected to the DC side of the inverter module;

[0007] The first end of the GOOSE network switch is connected to the energy storage system, the photovoltaic system and the inverter module DC / AC, and the second end of the GOOSE network switch is connected to the first end of the coordination controller;

[0008] The first end of the MMS network switch is connected to the first end of the inverter module DC / AC, the energy storage system and the energy management system; the second end of the MMS network switch is connected to the first end of the optical fiber terminal box;

[0009] The second end of the energy management system is connected to the photovoltaic system;

[0010] The second end of the optical fiber terminal box is connected to the dispatching system.

[0011] In a possible implementation, the photovoltaic system includes a photovoltaic DC / DC and a photovoltaic module, and the photovoltaic DC / DC is connected to the photovoltaic module;

[0012] The energy storage system includes an energy storage DC / DC, an energy storage battery and a BMS unit. The energy storage battery is connected to the BMS unit, and the BMS unit is connected to the energy storage DC / DC.

[0013] In a possible implementation, the first end of the GOOSE network switch is connected to the energy storage DC / DC of the energy storage system, the photovoltaic DC / DC of the photovoltaic system, and the inverter module DC / AC through an RJ45 network port, and the protocol is IEC 61850-GOOSE;

[0014] The second end of the GOOSE network switch is connected to the coordination controller via an RJ45 network port, and the protocol is IEC61850-GOOSE.

[0015] In a possible implementation, the first end of the MMS network switch is connected to the inverter module DC / AC, the BMS unit and the energy management system through an RJ45 network port, and the protocol is IEC61850-MMS;

[0016] The second end of the MMS network switch is connected to the optical fiber terminal box through an optical port, and the protocol is IEC61850-MMS.

[0017] In a possible implementation, the second end of the energy management system is also connected to an energy storage watt-hour meter and a non-electricity signal device;

[0018] The second end of the energy management system is connected to the energy storage watt-hour meter, the non-electricity signal device and the photovoltaic DC / DC of the photovoltaic system through the RS485 serial port;

[0019] The first end of the energy management system is connected to the first end of the MMS network switch through a network port.

[0020] In a possible implementation, the second end of the coordination controller is connected to the optical fiber distribution frame through an optical port, and the protocol is IEC 61850.

[0021] In a possible implementation, the GOOS network switch collects information of energy storage DC / DC, photovoltaic DC / DC and inverter module DC / AC, and uploads it to the coordination controller;

[0022] The MMS network switch collects information of the BMS unit and information of the energy management system, and uploads it to the dispatching system;

[0023] The BMS unit collects energy storage battery information;

[0024] The energy management system collects information of electric meter and non-electric signal equipment;

[0025] The coordination controller is connected to the transformer via a cable and is used to collect current information on the low-voltage side of the box-type transformer from the transformer via the cable.

[0026] In a possible implementation, the coordination controller includes a calculation module, a control module, an input module and an output module.

[0027] According to one aspect of the present disclosure, a communication control method for a DC-coupled photovoltaic storage system is provided, based on the above-mentioned DC-coupled photovoltaic storage system, comprising:

[0028] The coordination controller receives the dispatch instruction P1 from the dispatch system;

[0029] Compare the dispatch instruction P1 with 1.1 times the rated power of the box-type transformer and calculate the minimum value of the two, which is recorded as P max ;

[0030] Collect photovoltaic DC / DC power P;

[0031] The coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons;

[0032] When P = P max When , the energy storage system stops charging or discharging;

[0033] When P>P max When the coordinated controller controls the energy storage DC / DC to start charging;

[0034] When P <P max When , the coordinated controller controls the energy storage DC / DC to start discharging;

[0035] After the energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value;

[0036] The low-voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections so that P 箱 =P max .

[0037] According to one aspect of the present disclosure, a communication control method for a DC-coupled photovoltaic storage system is provided, based on the above-mentioned DC-coupled photovoltaic storage system, comprising:

[0038] The coordinated controller collects the power P at the inverter module DC / AC 逆 Compare with 1.1 times the rated power of the box-type transformer, and take the smaller value as P max ;

[0039] Collect photovoltaic DC / DC power P;

[0040] The coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons;

[0041] When P = P max When the energy storage system stops charging or discharging;

[0042] When P>P max When the coordinated controller controls the energy storage DC / DC to start charging;

[0043] When P <P maxWhen , the coordinated controller controls the energy storage DC / DC to start discharging;

[0044] After the energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value;

[0045] The low voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections so that P 箱 =P max .

[0046] The exemplary embodiments of the present disclosure have the following beneficial effects: the exemplary embodiments of the present disclosure add a coordination controller, a GOOSE network switch and an MMS network switch to the traditional DC-side coupled photovoltaic storage control system, rebuild the communication control system, and the coordination controller directly controls the photovoltaic DC / DC, the inverter module DC / AC, and the energy storage DC / DC, with fast response and high precision, and the coordination controller can flexibly adjust the output threshold of the photovoltaic storage system according to the real-time output of the inverter module.

[0047] The details of one or more embodiments of the present application are presented in the following drawings and descriptions. Other features and advantages of the present application will become apparent from the accompanying drawings. It should be understood that the above general description and the detailed descriptions below are only exemplary and explanatory and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0049] Figure 1 It is a control block diagram of a DC-side coupled DC-coupled photovoltaic storage system including energy storage DC / DC in the prior art;

[0050] Figure 2 is a primary system diagram of a DC / DC coupled photovoltaic storage system including energy storage according to this exemplary embodiment;

[0051] Figure 3 is a communication block diagram of a DC / DC coupled photovoltaic storage system including energy storage according to this exemplary embodiment;

[0052] Figure 4 is a control diagram of a DC / DC coupled photovoltaic storage system with energy storage according to the exemplary embodiment;

[0053] Figure 5is a schematic diagram of a coordination controller module of this exemplary embodiment;

[0054] Figure 6 is one of the flow charts of the communication control method of the DC-coupled photovoltaic storage system of this exemplary embodiment;

[0055] Figure 7 This is the second flow chart of the communication control method of the DC-coupled photovoltaic storage system of this exemplary embodiment. DETAILED DESCRIPTION

[0056] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0057] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware units or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0058] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the steps. For example, some steps may be decomposed, while some steps may be combined or partially combined, so the actual execution order may change according to the actual situation.

[0059] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example.

[0060] In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or sub-modules is not necessarily limited to those steps or sub-modules explicitly listed, but may include other steps or sub-modules not explicitly listed or inherent to these processes, methods, products, or apparatuses.

[0061] Figure 2 is a primary system diagram of a DC / DC coupled photovoltaic storage system including energy storage according to this exemplary embodiment, such as Figure 2 As shown, an exemplary embodiment of the present disclosure provides a DC-coupled photovoltaic storage system, including: a coordination controller, a GOOSE network switch, an MMS network switch, an inverter module DC / AC, an optical fiber terminal box, an energy management system (EMU), a photovoltaic system, an energy storage system, and a dispatching system;

[0062] The photovoltaic system and the energy storage system are connected to the DC side of the inverter module;

[0063] The first end of the GOOSE network switch is connected to the energy storage system, the photovoltaic system and the inverter module DC / AC, and the second end of the GOOSE network switch is connected to the first end of the coordination controller;

[0064] The first end of the MMS network switch is connected to the first end of the inverter module DC / AC, the energy storage system and the energy management system (EMU); the second end of the MMS network switch is connected to the first end of the optical fiber terminal box;

[0065] The second end of the energy management system (EMU) is connected to the photovoltaic system;

[0066] The second end of the optical fiber terminal box is connected to the dispatching system.

[0067] This exemplary embodiment adds a coordination controller, a GOOSE network switch and an MMS network switch to the traditional DC-side coupled photovoltaic storage control system, and rebuilds the communication control system. The coordination controller directly controls the photovoltaic DC / DC, the inverter module DC / AC, and the energy storage DC / DC, with fast response and high precision. In addition, the coordination controller can flexibly adjust the output threshold of the photovoltaic storage system according to the real-time output of the inverter module.

[0068] like Figure 2As shown, this exemplary embodiment includes a DC-coupled photovoltaic storage system with energy storage DC / DC. Both the photovoltaic and energy storage systems are connected to the DC / AC side of the inverter module. The photovoltaic DC / DC, that is, the MPPT type junction box, controls the photovoltaic system after receiving instructions from the coordination controller, and the energy storage DC / DC controls the charging and discharging of the energy storage system after receiving instructions from the coordination controller. The DC-coupled photovoltaic storage system including the energy storage DC / DC is more friendly to the voltage range of the energy storage system, while the voltage range of the DC-coupled photovoltaic storage system without the energy storage DC / DC must match the voltage of the inverter module, which is technically difficult.

[0069] Specifically, the photovoltaic system includes a photovoltaic DC / DC and a photovoltaic module, and the photovoltaic DC / DC is connected to the photovoltaic module;

[0070] The energy storage system includes an energy storage DC / DC, an energy storage battery and a BMS unit. The energy storage battery is connected to the BMS unit, and the BMS unit is connected to the energy storage DC / DC.

[0071] Specifically, the first end of the GOOSE network switch is connected to the energy storage DC / DC of the energy storage system, the photovoltaic DC / DC of the photovoltaic system, and the inverter module DC / AC through the RJ45 network port, and the protocol is IEC 61850-GOOSE;

[0072] The second end of the GOOSE network switch is connected to the coordination controller via an RJ45 network port, and the protocol is IEC61850-GOOSE.

[0073] Specifically, the first end of the MMS network switch is connected to the inverter module DC / AC, the BMS unit and the energy management system (EMU) through the RJ45 network port, and the protocol is IEC61850-MMS;

[0074] The second end of the MMS network switch is connected to the optical fiber terminal box through an optical port, and the protocol is IEC61850-MMS.

[0075] Specifically, the second end of the energy management system (EMU) is also connected to the energy storage watt-hour meter and the non-electrical quantity signal device;

[0076] The second end of the energy management system (EMU) is connected to the energy storage watt-hour meter, the non-electric quantity signal device and the photovoltaic DC / DC of the photovoltaic system through the RS485 serial port;

[0077] The first end of the energy management system (EMU) is connected to the first end of the MMS network switch through a network port.

[0078] Specifically, the second end of the coordination controller is connected to the optical fiber distribution frame through an optical port, and the protocol is IEC61850.

[0079] Specifically, the GOOS network switch collects information of energy storage DC / DC, photovoltaic DC / DC and inverter module DC / AC, and uploads it to the coordination controller;

[0080] The MMS network switch collects information of the BMS unit and information of the energy management system (EMU), and uploads it to the dispatching system;

[0081] The BMS unit collects energy storage battery information;

[0082] The energy management system (EMU) collects information of watt-hour meters and non-electricity signal devices;

[0083] The coordination controller is connected to the transformer via a cable and is used to collect current information on the low-voltage side of the box-type transformer from the transformer via the cable.

[0084] Figure 3 is a communication block diagram of a DC / DC coupled photovoltaic storage system including energy storage according to this exemplary embodiment. Figure 3 As shown, the GOOSE network switch is connected to the energy storage DC / DC, photovoltaic DC / DC, and inverter module DC / AC through the network port (RJ45) downward, and the protocol is IEC 61850-GOOSE; it is connected to the coordination controller through the network port upward, and the protocol is IEC 61850-GOOSE.

[0085] The MMS network switch is connected to the inverter module DC / AC, BMS, and EMU through the network port (RJ45) downward, and the protocol is IEC61850-MMS; it is connected to the fiber optic terminal box through the optical port upward, and the protocol is IEC61850-MMS.

[0086] The energy management system (EMU) is connected to the photovoltaic DC / DC, energy storage meter, non-electricity signal, etc. through the RS485 serial port; it is connected to the MMS network through the network port.

[0087] The coordination controller is connected to the GOOSE network and the current information on the low-voltage side of the box-type transformer downward, and is connected to the optical fiber distribution frame through the optical port upward. The protocol is IEC 61850.

[0088] BMS monitors the energy storage battery information and uploads it to the energy storage DC / DC and MMS network through the network port.

[0089] The GOOSE network collects information about energy storage DC / DC, photovoltaic DC / DC, and inverter module DC / AC, and uploads it to the coordination controller; the MMS network collects information about BMS and EMU and uploads it to the upper-level dispatcher; the coordination controller uses one cable to directly collect current information on the low-voltage side of the box transformer from the transformer; the BMS collects battery information, and the EMU collects information such as the electricity meter.

[0090] Figure 4 is a control diagram of a DC / DC coupled photovoltaic storage system including energy storage according to this exemplary embodiment, such as Figure 4 As shown, about the control system:

[0091] (1) The coordination controller is connected to the station control layer A, B, and C systems, receives control instructions from each system, and realizes steady-state (AGC / AVC control) and transient (primary frequency control) operation. The communication interfaces are independent of each other, and the communication protocol adopts IEC61850. It directly collects photovoltaic DC / DC, energy storage DC / DC, and inverter module DC / AC, and the communication protocol adopts IEC 61850.

[0092] (3) The coordinated controller directly collects the analog values ​​of voltage and current on the low-voltage side of the boost transformer, as shown by the yellow line in the figure.

[0093] (4) Coordinate the controller to access the action signal (dry contact) of the box-type transformer measurement and control device (including protection function).

[0094] (5) The coordinated controller output controls the inverter module DC / AC and energy storage DC / DC to reduce power urgently in the event of a transformer failure. It can also control the opening and closing of the low-voltage side circuit breaker of the box transformer and the circuit breaker of the energy storage device.

[0095] (6) The coordination controller collects the internal information of the photovoltaic and energy storage power generation units in real time. It can accept various system control instructions from the station control layer, coordinate photovoltaic power generation and energy storage charging and discharging according to the remote control instructions, and realize photovoltaic and energy storage combined power generation (steady-state operation), peak load regulation (steady-state operation), primary frequency regulation (transient operation) and other functions; it can also compare the collected photovoltaic output value with the rated capacity of the box transformer, automatically and dynamically set the output control power threshold for the day on site, and use this threshold as an instruction to realize photovoltaic and energy storage combined power generation (steady-state operation).

[0096] Figure 5 is a schematic diagram of a coordination controller module of this exemplary embodiment, such as Figure 5 As shown, the coordination controller is a controller including an operation module, a control module, an input module and an output module.

[0097] Figure 6 is one of the flow charts of the communication control method of the DC-coupled photovoltaic storage system of this exemplary embodiment. Figure 6 As shown, an exemplary embodiment of the present disclosure provides a communication control method for a DC-coupled photovoltaic storage system, based on the above DC-coupled photovoltaic storage system, including:

[0098] S1 coordination controller receives the dispatch instruction P1 of the dispatch system;

[0099] S2 compares the dispatch instruction P1 with 1.1 times the rated power of the box-type transformer and calculates the minimum value of the two, which is recorded as P max(Here is to ensure P max Not exceeding 1.1 times the rated power of the box-type transformer);

[0100] S3 collects photovoltaic DC / DC power P;

[0101] The S4 coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons;

[0102] S5 When P = P max When the energy storage system is neither charged nor discharged;

[0103] S6When P>P max When the coordinated controller controls the energy storage DC / DC to start charging;

[0104] S71 when P <P max When , the coordinated controller controls the energy storage DC / DC to start discharging;

[0105] After the S8 energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value;

[0106] S9 converts the low voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections again to make P 箱 =P max .

[0107] Figure 7 This is the second flow chart of the communication control method of the DC-coupled photovoltaic storage system of this exemplary embodiment. Figure 7 As shown, an exemplary embodiment of the present disclosure provides a communication control method for a DC-coupled photovoltaic storage system, based on the above DC-coupled photovoltaic storage system, including:

[0108] S10 The coordination controller does not accept the dispatch instruction. The coordination controller collects the power P at the inverter module DC / AC. 逆 Compare with 1.1 times the rated power of the box-type transformer, and take the smaller value as P max ;

[0109] S20 collects photovoltaic DC / DC power P;

[0110] The S30 coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons;

[0111] S40 When P=P max When , the energy storage system stops charging or discharging;

[0112] S50When P>P max When the coordinated controller controls the energy storage DC / DC to start charging;

[0113] S60 when P <P max When , the coordinated controller controls the energy storage DC / DC to start discharging;

[0114] After the S70 energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value;

[0115] S80 changes the low voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections so that P 箱 =P max .

[0116] In this exemplary embodiment, the control module requires that the coordination controller can directly control the inverter module or its data collector, photovoltaic DC / DC, energy storage DC / DC, etc., can control multiple energy storage DC / DCs to operate in parallel, and evenly distribute the power of multiple energy storage DC / DCs according to the SOC value of each battery pack, and balance the SOC value of each battery pack. Each communication interface is independent, and can accept and quickly execute various types of superior scheduling. According to the real-time collection of photovoltaic output, the dynamic photovoltaic power generation unit output control threshold can be automatically set on-site according to different weather conditions to avoid the problem of low energy storage utilization in cloudy weather and the inability to put the energy storage into operation in cloudy weather.

[0117] The input and output modules are required to have various interface types such as multiple network ports, optical ports, serial ports, etc., and the protocols must support unified protocols such as IEC 61850, IEC604, Modbus, etc.

[0118] It is worth noting that the coordination controller is a coordination controller that can be equipped with a protocol conversion device. In the control communication, the GOOSE network and the MMS network may not be constructed, and all devices are directly connected to the coordination controller.

[0119] In summary, this embodiment can better control the charging and discharging of energy storage batteries, making the photovoltaic storage system respond faster, the control mode simpler, and fewer links. During the debugging process of the photovoltaic storage system, it is also possible to more intuitively debug data at all levels and find problems in the operation process.

[0120] The above are only preferred implementations of the present disclosure, and the protection scope of the present disclosure is not limited to the above embodiments. All technical solutions under the concept of the present disclosure belong to the protection scope of the present disclosure. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present disclosure should be regarded as the protection scope of the present disclosure.

Claims

1. A DC-coupled photovoltaic storage system, characterized in that: include: Coordination controller, GOOSE network switch, MMS network switch, inverter module DC / AC, fiber optic terminal box, energy management system, photovoltaic system, energy storage system and dispatching system; The photovoltaic system and the energy storage system are connected to the DC side of the inverter module; The first end of the GOOSE network switch is connected to the energy storage system, the photovoltaic system and the inverter module DC / AC, and the second end of the GOOSE network switch is connected to the first end of the coordination controller; The first end of the MMS network switch is connected to the first end of the inverter module DC / AC, the energy storage system and the energy management system; the second end of the MMS network switch is connected to the first end of the optical fiber terminal box; The second end of the energy management system is connected to the photovoltaic system; The second end of the optical fiber terminal box is connected to the dispatching system.

2. The DC-coupled photovoltaic storage system according to claim 1, characterized in that: The photovoltaic system includes a photovoltaic DC / DC and a photovoltaic module, and the photovoltaic DC / DC is connected to the photovoltaic module; The energy storage system includes an energy storage DC / DC, an energy storage battery and a BMS unit. The energy storage battery is connected to the BMS unit, and the BMS unit is connected to the energy storage DC / DC.

3. The DC-coupled photovoltaic storage system according to claim 2, characterized in that: The first end of the GOOSE network switch is connected to the energy storage DC / DC of the energy storage system, the photovoltaic DC / DC of the photovoltaic system, and the inverter module DC / AC through the RJ45 network port, and the protocol is IEC 61850-GOOSE; The second end of the GOOSE network switch is connected to the coordination controller via an RJ45 network port, and the protocol is IEC 61850-GOOSE.

4. The DC-coupled photovoltaic storage system according to claim 3, characterized in that: The first end of the MMS network switch is connected to the inverter module DC / AC, the BMS unit and the energy management system through the RJ45 network port, and the protocol is IEC61850-MMS; The second end of the MMS network switch is connected to the optical fiber terminal box through an optical port, and the protocol is IEC61850-MMS.

5. The DC-coupled photovoltaic storage system according to claim 4, characterized in that: The second end of the energy management system is also connected to the energy storage watt-hour meter and the non-electricity signal device; The second end of the energy management system is connected to the energy storage watt-hour meter, the non-electricity signal device and the photovoltaic DC / DC of the photovoltaic system through the RS485 serial port; The first end of the energy management system is connected to the first end of the MMS network switch through a network port.

6. The DC-coupled photovoltaic storage system according to claim 5, characterized in that: The second end of the coordination controller is connected to the optical fiber distribution frame through an optical port, and the protocol is IEC 61850.

7. The DC-coupled photovoltaic storage system according to claim 6, characterized in that: The GOOS network switch collects information of energy storage DC / DC, photovoltaic DC / DC and inverter module DC / AC, and uploads it to the coordination controller; The MMS network switch collects information of the BMS unit and the energy management system, and uploads it to the dispatching system; The BMS unit collects energy storage battery information; The energy management system collects information of electric meter and non-electric signal equipment; The coordination controller is connected to the transformer via a cable and is used to collect current information on the low-voltage side of the box-type transformer from the transformer via the cable.

8. The DC-coupled photovoltaic storage system according to claim 7, characterized in that: The coordination controller includes a calculation module, a control module, an input module and an output module.

9. A communication control method for a DC-coupled photovoltaic storage system, characterized in that: The DC-coupled photovoltaic storage system according to any one of claims 1 to 8 comprises: The coordination controller receives the dispatch instruction P1 from the dispatch system; Compare the dispatch instruction P1 with 1.1 times the rated power of the box-type transformer and calculate the minimum value of the two, which is recorded as P max ; Collect photovoltaic DC / DC power P; The coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons; When P = P max When the energy storage system stops charging or discharging; When P>P max When the coordinated controller controls the energy storage DC / DC to start charging; When P <P max When , the coordinated controller controls the energy storage DC / DC to start discharging; After the energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value; The low voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections so that P 箱 =P max .

10. A communication control method for a DC-coupled photovoltaic storage system, characterized in that: The DC-coupled photovoltaic storage system according to any one of claims 1 to 8 comprises: The coordinated controller collects the power P at the inverter module DC / AC 逆 Compare with 1.1 times the rated power of the box-type transformer, and take the smaller value as P max ; Collect photovoltaic DC / DC power P; The coordinated controller converts the photovoltaic DC / DC power P and P max Make comparisons; When P = P max When the energy storage system stops charging or discharging; When P>P max When the coordinated controller controls the energy storage DC / DC to start charging; When P <P max When , the coordinated controller controls the energy storage DC / DC to start discharging; After the energy storage system is activated, the coordinated controller collects the low-voltage side power P of the transformer 箱 As feedback value; The low voltage side power P 箱 With P max After comparison, the coordinated controller is used to make corrections so that P 箱 =P max .

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