Collecting device, control device and method of distributed photovoltaic access area power distribution network

Abstract

The invention provides a collecting device, a control device and a control method of a distributed photovoltaic access regional power distribution network. The collecting device comprises a distributed photovoltaic collecting circuit which accesses a regional power distribution network zone area; the distributed photovoltaic collection circuit is connected with a plurality of distributed photovoltaics and is used for collecting and converting electric energy generated by the plurality of distributed photovoltaics through cooperation of a collection bus and an inverter; acquiring current, voltage and power after electric energy conversion as grid-connected data of the distributed photovoltaic system and sending the grid-connected data; receiving the collected distributed photovoltaic electric energy and controlling the collected distributed photovoltaic electric energy to access a transformer area of a regional power distribution network based on the control instruction; according to the collecting device provided by the invention, the problem of high difficulty in coordination control of each inverter in an existing access mode is solved, the power quality problem of a distributed photovoltaic grid-connected point is improved, the inverter investment and operation and maintenance cost are further reduced, the operation safety of a power grid is ensured, and the distributed photovoltaic absorption capability and the comprehensive utilization efficiency are improved; and local autonomous management of distributed photovoltaic electric energy is realized.

Description

Technical Field

[0001] The present invention belongs to the field of energy router design, and in particular relates to a collection device, a control device and a method for accessing a distributed photovoltaic power distribution network to a regional distribution network. Background Art

[0002] With the high penetration rate of distributed photovoltaic access, the structure of the regional distribution network has changed from the traditional radial type to a multi-terminal power supply structure, and its power flow and fault current may flow in both directions, which brings new problems to the relay protection and feeder automation of the regional distribution network: In terms of equipment-level safety, clean energy represented by photovoltaics is mainly distributed in rural and other economically underdeveloped areas, and problems such as "source" and "load" mismatch, reverse heavy overload, and voltage over-limit are prominent. The long-term overload operation of transformers and frequent damage to switches caused by photovoltaic overcapacity seriously affect the service life of transformers, affect the quality of power, and endanger the safety of power grid operation. In terms of system-level safety, in the scenario of high-proportion clean energy access, the existing distribution network has a serious lack of capacity to absorb new energy. As more and more distributed energy is connected to the distribution network, even power flow reverse transmission occurs, which not only increases the loss of power grid operation and reduces economic efficiency, but also leads to voltage fluctuations, overvoltage and other problems, seriously affecting the safe and reliable operation of the power grid, and causing difficulties in system planning and scheduling. In addition, with the development of regional photovoltaic power, after photovoltaic inverters, energy storage converters and other power electronic equipment are connected to the distribution network, the distribution network presents active and power electronic characteristics, facing power quality problems such as voltage fluctuation or flicker, harmonics and higher harmonics. To solve the above problems, some studies have used intelligent fusion terminals to achieve the regulation of distributed photovoltaic output power and solve some power quality problems caused by photovoltaic grid access; some studies have achieved the consumption of photovoltaic power through energy router technology, providing ideas for the dispatch of power resources. However, distributed photovoltaic power has not yet been included in the scope of grid monitoring and management. Neither intelligent fusion terminals nor energy routers can collect information such as voltage, current, and power generation of distributed photovoltaic power, which is not conducive to the correct decision-making of dispatch. The monitoring is difficult, which can easily cause disorderly power generation of distributed power sources, greatly affecting the regional power quality and power supply reliability, making it difficult to give full play to the corresponding resource advantages and drive local economic growth, and increasing the pressure on the grid. At present, grid-connected switches are gradually becoming intelligent, with the function of collecting data such as voltage, current and power, and also have communication capabilities. How to effectively use grid-connected switches is a major focus in solving the problem of distributed photovoltaic grid access.

[0003] like Figure 1The figure shows the structure of a photovoltaic power generation system, including a DC / DC converter, an MPPT (maximum power point tracking) algorithm, a DC / AC grid-connected inverter, and related control methods. The MPPT algorithm enables the photovoltaic array to stably output the maximum power, which is connected to the DC bus by a DC / DC converter, and then connected to the AC grid through an isolation transformer via a DC / AC grid-connected inverter. Existing photovoltaic grid-connected systems all use the method of connecting the grid-connected inverter to the grid point separately, one of which is a public grid distribution box or line. A single grid-connected point reference capacity is no more than 100kW and uses three-phase access; a capacity of 8kW or less uses single-phase access, such as Figure 2 As shown; Another public connection point is the public power distribution room or box-type transformer low-voltage busbar. The reference capacity of a single grid connection point is 20kW~400kW. Figure 3 As shown. It can be seen that the existing access scheme has low flexibility and cannot meet the growing demand for distributed photovoltaic grid connection. In addition, the access to a single grid connection point increases the difficulty of coordinated control of grid-connected inverters, which is not conducive to the improvement and enhancement of the power quality problems of distributed photovoltaic grid connection points. It is impossible to achieve distributed photovoltaic autonomous operation and interconnection between stations, resulting in insufficient distributed photovoltaic absorption capacity. In addition, the existing access scheme cannot simultaneously cope with the development of regional photovoltaics and the independent development of photovoltaics within the region. In view of the above problems, it is necessary to propose a solution for distributed photovoltaics to access the regional distribution network. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies of the prior art, the present invention proposes a collection device for connecting distributed photovoltaics to a regional distribution network, comprising: a distributed photovoltaic collection circuit connected to a regional distribution network station area;

[0005] The distributed photovoltaic collection circuit is connected to a number of distributed photovoltaics, and is used to collect and convert the electric energy generated by a number of distributed photovoltaics through the cooperation of a collection bus and an inverter; to obtain the current, voltage and power after the electric energy conversion and send them as distributed photovoltaic grid-connected data; and to receive and control the collected distributed photovoltaic electric energy to access the regional distribution network based on control instructions.

[0006] Preferably, the distributed photovoltaic collection circuit includes: a grid-connected switch, and one or more of a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit;

[0007] When the distributed photovoltaic is developed in the whole area of ​​the region, the DC collection circuit is connected to a number of distributed photovoltaics developed in the whole area of ​​the region, and is used to collect the electric energy of the distributed photovoltaics developed in the whole area of ​​the region through the collection bus, and convert it into AC power through the inverter;

[0008] When the distributed photovoltaics are independently developed in the region, the AC collection circuit is connected to a number of distributed photovoltaics independently developed in the region, and is used to convert the electric energy of each distributed photovoltaic into AC power through an inverter set one-to-one with each distributed photovoltaic independently developed in the region, and collect it through the collection bus;

[0009] The grid-connected switch is respectively connected to the DC collection circuit, the AC collection circuit and the substation of the regional distribution network, and is used to obtain the current, voltage and power converted into AC power and send them as distributed photovoltaic grid-connected data; it is used to receive and close the substation to connect AC power to the regional distribution network based on the control command, or receive and trip based on the control command;

[0010] Wherein, when a DC collection circuit and an AC collection circuit exist simultaneously in the distributed photovoltaic collection circuit, the DC collection circuit and the AC collection circuit are connected in series.

[0011] Preferably, the DC collection circuit comprises: a DC / DC converter, a DC collection bus and a grid-connected inverter;

[0012] The DC / DC converter is connected to a number of distributed photovoltaic power generation units developed in the entire region, and is used to boost the electric energy generated by the number of distributed photovoltaic power generation units developed in the entire region;

[0013] The DC collection bus is connected to the DC / DC converter and is used to collect the boosted electric energy;

[0014] The grid-connected inverter is connected to the DC collection bus and the grid-connected switch respectively, and is used to convert the collected electric energy into alternating current.

[0015] Preferably, the AC collection circuit comprises: an AC collection bus and inverters equal in number to the distributed photovoltaics;

[0016] The inverter is connected one-to-one with each distributed photovoltaic power generation unit independently developed in the region, and is used to convert the electric energy generated by each distributed photovoltaic power generation independently developed in the region into alternating current;

[0017] The AC collection bus is connected to the inverter and the grid-connected switch respectively, and is used to collect the converted AC power.

[0018] Based on the same inventive concept, the present invention also provides a control device for accessing a regional distribution network to a distributed photovoltaic system, including: an energy router accessing a regional distribution network station, an intelligent fusion terminal, and a collection device for accessing a regional distribution network to a distributed photovoltaic system;

[0019] The intelligent fusion terminal is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the grid-connected data of the equipment in the regional distribution network area and the grid-connected data of the distributed photovoltaic provided by the collection device; and based on the grid-connected data of the equipment and the grid-connected data of the distributed photovoltaic, generate and send control instructions to the distributed photovoltaic collection circuit of the collection device;

[0020] The energy router is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the power demand of the equipment in the regional distribution network area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, distribute the distributed photovoltaic power to the equipment for consumption;

[0021] Wherein, the collection device is the collection device of the distributed photovoltaic access regional distribution network; the equipment in the access regional distribution network station area includes one or more of energy storage and load;

[0022] The connection mode of the intelligent fusion terminal with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection; the connection mode of the energy router with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection.

[0023] Preferably, the intelligent fusion terminal is specifically used for:

[0024] Calculate the power quality of the distribution network based on the grid-connected data of the equipment and the grid-connected data of distributed photovoltaics;

[0025] A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

[0026] Preferably, the energy router comprises: interfaces for distributed photovoltaic, energy storage and load;

[0027] Distributed photovoltaic interface, used to obtain distributed photovoltaic power;

[0028] The interface between energy storage and load is used to obtain the power demand of energy storage and load; and output the power generated by distributed photovoltaic to energy storage and load.

[0029] Preferably, the energy router is specifically used for:

[0030] Obtaining distributed photovoltaic power through the distributed photovoltaic interface;

[0031] Obtaining the electric energy demand of the energy storage and the load through the interface of the energy storage and the load;

[0032] Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load;

[0033] Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

[0034] Based on the same inventive concept, the present invention also provides a control method for accessing a distributed photovoltaic power generation system to a regional power distribution network, comprising:

[0035] The distributed photovoltaic collection circuit of the control device of the distributed photovoltaic access regional power distribution network is used to collect and convert the electric energy generated by a number of distributed photovoltaics, and the current, voltage and power after the electric energy conversion are obtained and sent as the distributed photovoltaic grid-connected data;

[0036] Through the intelligent fusion terminal of the control device of the distributed photovoltaic access to the regional distribution network, the grid-connected data of the equipment and distributed photovoltaic in the regional distribution network station area are obtained and the control instructions are sent to the distributed photovoltaic collection circuit of the collection device;

[0037] Obtaining, through the distributed photovoltaic collection circuit, and connecting the collected electric energy to the substation of the regional distribution network based on the control instruction;

[0038] The energy router of the control device of the distributed photovoltaic access regional distribution network is used to obtain the power demand of the equipment in the regional distribution network station area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, the distributed photovoltaic power is distributed to the equipment for consumption;

[0039] Wherein, the method adopts the control device for distributed photovoltaic access to the regional distribution network to control the distributed photovoltaic access to the regional distribution network.

[0040] Preferably, the distributed photovoltaic collection circuit of the control device of the distributed photovoltaic access regional power distribution network collects and converts the electric energy generated by a plurality of distributed photovoltaics, including:

[0041] When the distributed photovoltaic is developed in the whole area of ​​the region, the DC collection circuit of the distributed photovoltaic collection circuit is used to collect the electric energy of several distributed photovoltaics developed in the whole area of ​​the region by using the collection bus, and the DC is converted into AC by using the inverter;

[0042] When the distributed photovoltaic is independently developed in a region, the AC collection circuit of the distributed photovoltaic collection circuit is used to convert the electric energy of each distributed photovoltaic into AC power by using inverters that are one-to-one set with each distributed photovoltaic independently developed in the region, and the AC power is collected using a collection bus.

[0043] Preferably, the DC collection circuit through the distributed photovoltaic collection circuit uses a collection bus to collect the DC power of a plurality of distributed photovoltaics, and uses an inverter to convert the collected DC power into AC power, including:

[0044] The electric energy generated by a number of distributed photovoltaic systems developed in the entire area is boosted through a DC / DC converter of the DC collection circuit;

[0045] The boosted electric energy is collected through the DC collection busbar of the DC collection circuit;

[0046] The collected electric energy is converted into alternating current through the grid-connected inverter of the direct current collection circuit.

[0047] Preferably, the AC collection circuit through the distributed photovoltaic collection circuit uses an inverter that is set one-to-one with the distributed photovoltaic to convert the DC power of each distributed photovoltaic into AC power, and uses a collection bus to collect the AC power, including:

[0048] The electric energy generated by each distributed photovoltaic independently developed in the area is converted into alternating current through an inverter arranged one-to-one with the distributed photovoltaic in the alternating current collection circuit;

[0049] The converted alternating current is collected through the alternating current collection busbar of the alternating current collection circuit.

[0050] Preferably, the intelligent fusion terminal of the control device of the distributed photovoltaic access to the regional distribution network obtains and sends control instructions to the distributed photovoltaic collection circuit of the collection device based on the equipment and distributed photovoltaic grid-connected data in the regional distribution network station area, including:

[0051] Based on the grid-connected data of the equipment and distributed photovoltaics, the power quality of the distribution network is calculated through the intelligent fusion terminal;

[0052] A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

[0053] Preferably, the step of obtaining, through the distributed photovoltaic collection circuit, and connecting the collected electric energy to the substation of the regional distribution network based on the control instruction includes:

[0054] The grid-connected switch of the distributed photovoltaic collection circuit receives and closes based on the control instruction to connect the AC power to the substation of the regional distribution network; or receives and trips based on the control instruction.

[0055] Preferably, the energy router of the control device of the regional distribution network accessed by the distributed photovoltaic obtains the power demand of the equipment in the regional distribution network station area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, distributes the distributed photovoltaic power to the equipment for consumption, including:

[0056] Obtaining distributed photovoltaic power through the distributed photovoltaic interface of the energy router;

[0057] Obtaining the electric energy demand of the energy storage and the load through the energy storage and load interfaces of the energy router;

[0058] Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load;

[0059] Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

[0060] Based on the same inventive concept, the present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed, the control method for accessing the distributed photovoltaic power generation to the regional power distribution network is implemented.

[0061] Compared with the closest prior art, the present invention has the following beneficial effects:

[0062] 1. The present invention provides a collection device, a control device and a method for connecting distributed photovoltaic power to a regional distribution network, including: a distributed photovoltaic collection circuit connected to a regional distribution network substation; the distributed photovoltaic collection circuit is connected to a number of distributed photovoltaic power stations, and is used to collect and convert the electric energy generated by a number of distributed photovoltaic power stations through the cooperation of a collection bus and an inverter; is used to obtain the current, voltage and power after the electric energy conversion and send them as the grid-connected data of the distributed photovoltaic power stations; and is used to receive and control the collected distributed photovoltaic power stations to access the regional distribution network substation based on control instructions; the collection device provided by the present invention collects the electric energy of a number of distributed photovoltaic power stations and then connects them to the distribution network through the cooperation of a collection bus and an inverter, which solves the problem of high difficulty in coordinated control of each inverter caused by the existing access method of connecting to the grid point through a grid-connected inverter alone, and improves the power quality problem of the distributed photovoltaic grid-connected point by collecting the electric energy of the distributed photovoltaic power stations, thereby reducing the investment and operation and maintenance costs of the inverter; by adding a grid-connected switch to the collection device, the acquisition capability of the grid-connected switch for power data can be fully utilized, and the collected distributed photovoltaic power station is connected to the distribution network through the grid-connected switch, thereby realizing efficient access to the distributed photovoltaic power stations;

[0063] 2. The collection device proposed in the present invention includes two collection circuits, namely, a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit. The DC collection circuit is used for access to distributed photovoltaics developed in the entire region by first collecting and then converting to AC power through a unified grid-connected inverter; the AC collection circuit is used for access to distributed photovoltaics developed independently in the region by first converting AC power through a one-to-one inverter and then collecting. The two collection currents are connected in series to cope with two development situations at the same time, solving the problem of the singleness of the existing access scheme.

[0064] 3. The present invention utilizes the data acquisition capability of the grid-connected switch to provide data such as current, voltage and power for the intelligent fusion terminal. The current, voltage and power are monitored through the existing intelligent fusion terminal, and the amount of distributed photovoltaic power entering the grid can be controlled by controlling the closing and tripping of the grid-connected switch, thereby improving the quality of power and ensuring the safe operation of the power grid. The energy router with multiple access ports such as photovoltaic, energy storage and load is used to absorb the photovoltaic power connected to the distribution network, thereby improving the absorption capacity and comprehensive utilization efficiency of distributed photovoltaic power, realizing on-site autonomous management of distributed photovoltaic power, and providing a basis for building a multi-level collaborative governance model for power management in substations. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 It is a schematic diagram of the structure of an existing photovoltaic power generation system;

[0066] Figure 2 This is a schematic diagram of the scheme 1 for connecting the existing distributed photovoltaic power generation to the distribution network;

[0067] Figure 3 This is a schematic diagram of the second scheme for connecting the existing distributed photovoltaic power generation to the distribution network;

[0068] Figure 4 A basic structural diagram of a collection device for connecting distributed photovoltaic power to a regional power distribution network provided by the present invention;

[0069] Figure 5 A schematic diagram of the structure of a distributed photovoltaic DC collection circuit provided by the present invention;

[0070] Figure 6 A schematic diagram of the structure of a distributed photovoltaic AC collection circuit provided by the present invention;

[0071] Figure 7 A schematic diagram of the connection between the distributed photovoltaic collection circuit and the load provided by the present invention;

[0072] Figure 8 A basic structural diagram of a control device for accessing a regional power distribution network to a distributed photovoltaic system provided by the present invention;

[0073] Fig. 9A schematic diagram of the connection relationship of connecting distributed photovoltaics to a county distribution network station area using a control device for connecting distributed photovoltaics to a regional distribution network provided by the present invention;

[0074] Fig.10 A schematic diagram of the connection relationship of the control device for connecting distributed photovoltaic access to a regional power distribution network provided by the present invention to an AC / DC hybrid microgrid based on a 10kV energy router shore power system;

[0075] Fig.11 A schematic flow chart of a control method for accessing a regional power distribution network to a distributed photovoltaic system provided by the present invention. DETAILED DESCRIPTION

[0076] The security issues faced by the large-scale access of a high proportion of clean energy to the distribution network include: equipment-level security. When the daytime sunlight conditions are sufficient, the photovoltaic power generation increases. Some photovoltaic customers set the photovoltaic power station outlet voltage too high and relax the protection voltage range in order to unilaterally increase the power generation and pursue more photovoltaic benefits. Taking the survey results of Yishui County, Shandong Province, China as an example, some users relaxed the factory AC voltage to 160-300V adjustable, resulting in a high voltage at the photovoltaic access point and a voltage exceeding 242V on the photovoltaic customer side, causing the voltage of surrounding customers to exceed the upper limit. The photovoltaic outlet voltage can reach up to 300V during some periods, which seriously affects the power quality and easily causes surrounding users' electrical appliances to burn out and complaints. System-level security. The existing distribution network has a serious lack of capacity to absorb new energy, which seriously affects the safe and reliable operation of the power grid and creates difficulties for system planning and scheduling.

[0077] After large-scale distributed photovoltaic access, the reliability of distribution network operation is very high. At present, a large number of distributed controllable and adjustable sources and loads such as photovoltaic, distributed energy storage, and charging piles are connected in the region. Distributed photovoltaic has not yet been included in the scope of grid monitoring and management. If the distributed photovoltaic anti-islanding protection fails during the main distribution network outage for maintenance or construction, it will bring the risk of electric shock to the maintenance or construction personnel. There is an urgent need to improve the observability, measurability, adjustability, and controllability of regional distributed photovoltaic.

[0078] The region in the present invention can refer to the county in China, and the medium-voltage feeder of the county distribution network in China is long and the power supply area is large, which is prone to large voltage offset, high network loss, three-phase imbalance and other problems. For the county distribution system with a high proportion of new energy access, due to the intermittent and random nature of distributed photovoltaic output, it is very easy to cause the distribution transformer and line voltage fluctuations in the substation. The development of county distributed photovoltaics is divided into different situations such as overall development of the whole county and independent development within the county. Different development situations require different ways of distributed photovoltaic access. The existing solutions cannot cope with these two development situations at the same time. In addition, during the period of high photovoltaic output, it is easy to cause current return and terminal voltage rise, which will bring serious problems of power quality and power supply efficiency, limit the absorption of new energy, and bring about complex fault location and safety problems of operation and maintenance. At the same time, compared with conventional power sources, the output adjustability of distributed photovoltaics is poor, and conventional grids and conventional load resources will be difficult to limit the peak-to-valley difference in different time periods. The distribution network is required to have the ability to actively adjust the voltage and flexibly control the power to adapt to the flexible access of distributed photovoltaics.

[0079] The power quality problems caused by high proportion of photovoltaic access to the distribution network mainly include:

[0080] 1) When distributed photovoltaic power generation is connected to the distribution network and cannot be absorbed, the line impedance will increase the terminal voltage.

[0081] 2) Since the intensity of sunlight varies with seasons, time, weather, etc., the output of photovoltaic power generation is discontinuous, causing unstable changes in voltage and current, and may cause excessive operation of voltage regulation equipment, further worsening the voltage fluctuation / flicker problem.

[0082] 3) The unbalanced installation distribution of distributed photovoltaic power generation in the three-phase system directly leads to the imbalance of the three-phase system voltage. In addition, the imbalance of the load will further increase the imbalance.

[0083] 4) Due to the failure of sensitive loads or large industrial motor loads, the three-phase circuit breaker trips, causing the photovoltaic system to exit, resulting in a temporary voltage drop / rise in some areas.

[0084] 5) The harmonic problems generated by photovoltaic power generation devices are complex and diverse, and are directly related to the technology used in the photovoltaic power generation devices, including circuit topology, modulation method, control algorithm, filter design, etc., which can also cause harmonic problems.

[0085] Therefore, in order to solve the above problems, a collection device, a control device and a method for connecting distributed photovoltaic power to a regional distribution network are proposed. The specific implementation methods of the present invention are further described in detail below with reference to the accompanying drawings.

[0086] Embodiment 1:

[0087] The present invention provides a distributed photovoltaic access to a regional distribution network collection device, the basic structure diagram of which is as follows Figure 4 As shown, it includes: a distributed photovoltaic collection circuit connected to the regional distribution network station area;

[0088] The distributed photovoltaic collection circuit is connected to a number of distributed photovoltaics, and is used to collect and convert the electric energy generated by a number of distributed photovoltaics through the cooperation of a collection bus and an inverter; to obtain the current, voltage and power after the electric energy conversion and send them as distributed photovoltaic grid-connected data; and to receive and control the collected distributed photovoltaic electric energy to access the regional distribution network based on control instructions.

[0089] The existing technical solution for photovoltaic access to the county distribution network adopts the method of connecting distributed photovoltaics to the grid point separately through the grid-connected inverter, and then connecting to the public grid distribution box, line, box transformer low-voltage bus and other public connection points through the circuit breaker. On this basis, considering the problems of small single capacity and complex distributed coordinated control of distributed photovoltaic grid-connected inverters, the present invention proposes a distributed photovoltaic collection circuit. The distributed photovoltaic collection circuit includes: a grid-connected switch, and one or more of a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit;

[0090] When the distributed photovoltaic power generation is developed in the whole area of ​​the region, each distributed photovoltaic power generation unit is adjacent to the other. At this time, the DC collection circuit is connected to the distributed photovoltaic power generation units developed in the whole area of ​​the region, and is used to collect the DC power of the distributed photovoltaic power generation units developed in the whole area of ​​the region through the collection bus, and convert it into AC power through the inverter.

[0091] The DC collection circuit is that several distributed photovoltaic power generation units developed in the entire area are connected to the DC collection bus through DC / DC converters, and then connected to the public power grid through large-capacity grid-connected inverters;

[0092] The DC collection circuit has a structural schematic diagram as shown in Figure 5 As shown, it includes: a DC / DC converter (not shown in the figure), a DC bus and a grid-connected inverter;

[0093] The DC / DC converter is connected to a number of distributed photovoltaic power generation units developed in the entire region, and is used to boost the electric energy generated by the number of distributed photovoltaic power generation units developed in the entire region;

[0094] The DC collection bus is connected to the DC / DC converter and is used to collect the boosted electric energy;

[0095] The grid-connected inverter is connected to the DC collection bus and the grid-connected switch respectively, and is used to convert the collected electric energy into alternating current.

[0096] When the distributed photovoltaics are independently developed in the region, the AC collection circuit is connected to a number of distributed photovoltaics independently developed in the region, and is used to convert the electric energy of each distributed photovoltaic into AC electricity through an inverter set one-to-one with each distributed photovoltaic independently developed in the region, so as to achieve the aggregation of spatially close distributed photovoltaics, and collect them through the collection bus;

[0097] The AC collection circuit is that each distributed photovoltaic power generation unit independently developed in the region is equipped with an independent inverter, which is converted into AC and then collected through the AC collection bus, and then connected to the low-voltage network;

[0098] The AC collection circuit, its structural schematic diagram is as follows Figure 6 As shown, it includes: an AC collection bus and inverters equal to the number of distributed photovoltaics;

[0099] The inverter is connected one-to-one with each distributed photovoltaic power generation unit independently developed in the region, and is used to convert the electric energy generated by each distributed photovoltaic power generation independently developed in the region into alternating current;

[0100] The AC collection bus is connected to the inverter and the grid-connected switch respectively, and is used to collect the converted AC power.

[0101] Distributed on the basis of DC collection circuit and AC collection circuit, grid-connected switch and reversing switch (reversing switch, used to connect to step-up transformer) are set up to build network structure and form photovoltaic collection circuit;

[0102] The grid-connected switch is respectively connected to the DC collection circuit, the AC collection circuit and the substation of the regional distribution network, and is used to obtain the current, voltage and power converted into AC power and send them as distributed photovoltaic grid-connected data; it is used to receive and close the AC power based on the control instruction to first connect the AC power to the 380 / 220V low-voltage power grid, and then connect the AC power to the substation of the regional distribution network (i.e., the 10kV public line) via the reversing switch and the step-up transformer; or receive and trip based on the control instruction;

[0103] Wherein, when a DC collection circuit and an AC collection circuit exist simultaneously in the distributed photovoltaic collection circuit, the DC collection circuit and the AC collection circuit are connected in series.

[0104] Specifically, in the case of the overall development of distributed photovoltaics in the whole county, each power generation unit is adjacent to another. The electric energy generated by distributed photovoltaics can be collected through the collection device of the distributed photovoltaic access regional distribution network proposed in the present invention, and connected to the 10kV public line by the step-up transformer; when there are existing photovoltaics and other power loads, the distributed photovoltaics are first collected by the collection device of the distributed photovoltaic access regional distribution network, and then the collected distributed photovoltaic power and load are connected to the 10kV public line through the public network by the public distribution transformer, which can reduce the occupied space of the line channel, such as Figure 7 shown.

[0105] The collection device provided in this embodiment collects and converts the electric energy of several distributed photovoltaics through the cooperation of the collection bus and the inverter, solves the problem of high difficulty in coordinated control of each inverter in the existing access mode, solves the difficulty of distributed photovoltaic access, improves the power quality problem of distributed photovoltaic grid-connected points, and thus reduces the inverter investment and operation and maintenance costs; by adding a grid-connected switch to the collection device, the ability to obtain power data of the grid-connected switch can be fully utilized, and the collected distributed photovoltaic electric energy can be connected to the distribution network through the grid-connected switch, thereby realizing efficient access to high-proportion distributed photovoltaics; the collection device proposed in the present invention includes two collection circuits, a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit. The DC collection circuit can be used for the access of distributed photovoltaics developed in the entire area by first collecting and then converting to AC through a unified grid-connected inverter; the AC collection circuit can be used for the access of distributed photovoltaics independently developed in the region by first converting to AC through a one-to-one inverter and then collecting; by connecting the two collection currents in series, two development situations can be dealt with at the same time, solving the problem of the singleness of the existing access scheme.

[0106] Embodiment 2:

[0107] The present invention provides a control device for connecting distributed photovoltaic power to a regional power distribution network, and its basic structural diagram is shown in FIG. Figure 8 As shown, it includes: an energy router connected to the regional distribution network station area, an intelligent fusion terminal and a collection device for distributed photovoltaic access to the regional distribution network;

[0108] The intelligent fusion terminal is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the grid-connected data of the equipment in the regional distribution network area and the grid-connected data of the distributed photovoltaic provided by the collection device; and based on the grid-connected data of the equipment and the grid-connected data of the distributed photovoltaic, generate and send control instructions to the distributed photovoltaic collection circuit of the collection device;

[0109] The energy router is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the power demand of the equipment in the regional distribution network area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, distribute the distributed photovoltaic power to the equipment for consumption;

[0110] Wherein, the collection device is the collection device of the distributed photovoltaic access regional distribution network described in Example 1; the equipment in the access regional distribution network station area includes one or more of energy storage and load;

[0111] The connection mode of the intelligent fusion terminal with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection; the connection mode of the energy router with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection.

[0112] The control device for the distributed photovoltaic access to the regional distribution network shown is based on the aggregation device of the distributed photovoltaic access to the regional distribution network, and is designed in combination with energy router technology and intelligent fusion terminal. The photovoltaic, energy storage and adjustable loads (not shown in the figure, 7kW charging piles) connected to the distribution network are aggregated by the energy router to achieve the control of large-scale distributed photovoltaics and flexible interconnection with low-voltage substations. The grid-connected switches and inverters set at each grid-connected point are monitored and controlled in real time through the intelligent fusion terminal to achieve safe operation status monitoring of the distribution network substation.

[0113] The intelligent fusion terminal is specifically used for:

[0114] Calculate the power quality of the distribution network based on the grid-connected data of the equipment and the grid-connected data of distributed photovoltaics;

[0115] A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

[0116] The energy router includes: interfaces for distributed photovoltaic, energy storage and load;

[0117] Distributed photovoltaic interface, used to obtain distributed photovoltaic power;

[0118] The interface between energy storage and load is used to obtain the power demand of energy storage and load; and output the power generated by distributed photovoltaic to energy storage and load.

[0119] The energy router is specifically used for:

[0120] Obtaining distributed photovoltaic power through the distributed photovoltaic interface;

[0121] Obtaining the electric energy demand of the energy storage and the load through the interface of the energy storage and the load;

[0122] Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load;

[0123] Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

[0124] Through the control device provided in this embodiment, a high proportion of distributed photovoltaics can be safely connected to the county distribution network on the medium-voltage grid side and the low-voltage user side, and the power quality management and active grid support technology of high-proportion distributed generation grid connection points can be improved. It can realize regional intelligent autonomous control for the safe access needs of high-proportion distributed generation in the county, as well as the local autonomy of the distribution network under the high proportion of clean energy access, cross-regional and cross-layer complementarity and mutual assistance;

[0125] The present invention utilizes the data acquisition capability of the grid-connected switch to provide data such as current, voltage and power for the intelligent fusion terminal. The current, voltage and power are monitored through the existing intelligent fusion terminal, and the amount of distributed photovoltaic power entering the grid can be controlled by controlling the closing and tripping of the grid-connected switch, thereby improving the quality of power and ensuring the safe operation of the power grid. An energy router with multiple access ports such as photovoltaic, energy storage and load is used, and an aggregate analysis of photovoltaic, energy storage and adjustable load energy consumption is performed to absorb the photovoltaic power connected to the distribution network, thereby improving the distributed photovoltaic absorption capacity and comprehensive utilization efficiency, realizing on-site autonomous management of distributed photovoltaic power, and providing a basis for building a multi-level collaborative governance model for power management in substations.

[0126] Embodiment 3:

[0127] This embodiment provides an embodiment of a control device for connecting a distributed photovoltaic power plant to a regional power distribution network. Fig. 9 As shown, it is a schematic diagram of the connection relationship of connecting distributed photovoltaics to a county distribution network station area using a control device for connecting distributed photovoltaics to a regional distribution network provided by the present invention.

[0128] In the figure, the existing photovoltaics are connected to the public line through the collection device of the distributed photovoltaic access regional distribution network, and the photovoltaic status is detected through the grid-connected switch in the collection device. Other photovoltaics are connected to the public line through photovoltaic inverters, grid-connected switches and reversing switches; energy storage is connected to the public line through converters and grid-connected switches; loads (i.e. 7kW charging piles) are connected to the public line through grid-connected switches and reversing switches; then photovoltaic, energy storage and load equipment are connected to the distribution network through energy routers and intelligent fusion terminals. In the figure, each grid-connected point is equipped with a grid-connected switch for status detection of each device (i.e. obtaining grid-connected data of each device). The photovoltaic inverter, converter, grid-connected switch and reversing switch are all connected to the intelligent fusion terminal in communication. The communication line includes power HPLC or Lora (long-distance radio), and the communication line uplinks voltage, current, power and other grid-connected data, and the intelligent fusion terminal calculates and generates control instructions, and the communication line downlinks photovoltaic, energy storage, and load control instructions. The grid-connected switch is connected or disconnected based on the control instructions, thereby realizing the connection or disconnection of photovoltaic, energy storage, and load. Distributed resources such as photovoltaics, energy storage, and 7kW charging piles are aggregated and coordinated through energy routers to realize the consumption of photovoltaic power.

[0129] This embodiment can make full use of the power data acquisition capability of the grid-connected switch by adding a grid-connected switch to the collection device, and connect the collected distributed photovoltaic power to the distribution network through the grid-connected switch, thereby realizing efficient access of distributed photovoltaic power. The data acquisition capability of the grid-connected switch is utilized to provide current, voltage, power and other data to the intelligent fusion terminal, and the current, voltage and power are monitored through the existing intelligent fusion terminal. The amount of distributed photovoltaic power entering the grid can be controlled by controlling the closing and tripping of the grid-connected switch, thereby improving the power quality and ensuring the safe operation of the power grid. The photovoltaic power connected to the distribution network is absorbed by an energy router with multiple access ports such as photovoltaic, energy storage and load, thereby improving the absorption capacity and comprehensive utilization efficiency of distributed photovoltaic power, realizing on-site autonomous management of distributed photovoltaic power, and providing a basis for building a multi-level collaborative governance model for power management in substations.

[0130] Embodiment 4:

[0131] This embodiment provides an embodiment of a control device for connecting a distributed photovoltaic power plant to a regional power distribution network. Fig.10 As shown, it is a schematic diagram of the connection relationship of connecting the control device of the distributed photovoltaic access regional distribution network to the AC / DC hybrid microgrid based on the 10kV energy router shore power system. This embodiment does not involve the intelligent fusion terminal.

[0132] In the figure, photovoltaics are connected to the public line through the collection device of the regional distribution network connected to distributed photovoltaics (the figure shows the distributed photovoltaic AC collection circuit, the distribution box represents the AC collection bus and the grid-connected switch, and the DC / DC photovoltaic controller represents the inverter); in addition, the shore power equipment is connected to the public line through the DC / DC converter and the distribution box; the energy storage battery is connected to the public line through the DC / DC energy storage inverter; the AC load is connected to the public line through the AC / DC inverter; the charging pile reserved interface is connected to the public line through the distribution box; the public line is connected to the 10kV medium voltage network through the energy router. In addition, the energy router is connected to the DC / DC photovoltaic controller and DC / DC converter through Lora; the energy router is connected to the AC / DC inverter through the RS485 interface; the energy router is connected to the DC / DC energy storage inverter through Ethernet. The embedded microgrid EMS system in the energy router communicates up and down with the DC / DC photovoltaic controller, DC / DC converter, AC / DC inverter and DC / DC energy storage converter through Ethernet, LORA and RS485 to detect the operating status of the shore power system AC / DC hybrid microgrid. The embedded microgrid EMS system communicates wirelessly with the distribution dispatching master station and obtains dispatching instructions from the master station. The energy router uses the dispatching instructions to coordinate and control the electric energy in the grid in a unified and flexible manner.

[0133] This embodiment uses an energy router with multiple access ports such as photovoltaic, energy storage and load to absorb photovoltaic power connected to the distribution network, thereby improving the distributed photovoltaic absorption capacity and comprehensive utilization efficiency, realizing on-site autonomous management of distributed photovoltaic power, and providing a basis for building a multi-level collaborative governance model for power management in the substation area.

[0134] Embodiment 5:

[0135] Based on the same inventive concept, the present invention also provides a control method for connecting distributed photovoltaic power generation to a regional power distribution network. Fig.11 As shown, including:

[0136] Step 1: The distributed photovoltaic collection circuit of the control device of the distributed photovoltaic access regional distribution network is used to collect and convert the electric energy generated by a number of distributed photovoltaics, and the current, voltage and power after the electric energy conversion are obtained as the distributed photovoltaic grid-connected data for transmission;

[0137] Step 2: Obtain and send control instructions to the distributed photovoltaic collection circuit of the collection device based on the equipment and distributed photovoltaic grid-connected data in the regional distribution network area through the intelligent fusion terminal of the control device of the distributed photovoltaic access to the regional distribution network;

[0138] Step 3: Obtaining the collected electric energy through the distributed photovoltaic collection circuit and connecting it to the substation of the regional distribution network based on the control instruction;

[0139] Step 4: The energy router of the control device of the distributed photovoltaic access regional distribution network is used to obtain the power demand of the equipment in the regional distribution network station area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, the distributed photovoltaic power is distributed to the equipment for consumption;

[0140] The method adopts the control device for the distributed photovoltaic access regional distribution network described in Example 2 to control the distributed photovoltaic access regional distribution network.

[0141] Step 1 specifically includes:

[0142] When the distributed photovoltaic is developed in the whole area of ​​the region, the DC collection circuit of the distributed photovoltaic collection circuit is used to collect the electric energy of several distributed photovoltaics developed in the whole area of ​​the region by using the collection bus, and the DC is converted into AC by using the inverter;

[0143] The electric energy generated by a number of distributed photovoltaic systems developed in the entire area is boosted through a DC / DC converter of the DC collection circuit;

[0144] The boosted electric energy is collected through the DC collection bus of the DC collection circuit;

[0145] The collected electric energy is converted into alternating current through the grid-connected inverter of the direct current collection circuit.

[0146] When the distributed photovoltaics are independently developed in the region, the AC collection circuit of the distributed photovoltaic collection circuit is used to convert the electric energy of each distributed photovoltaic into AC power by using an inverter that is one-to-one with each distributed photovoltaic independently developed in the region, and the AC power is collected by using a collection bus;

[0147] The electric energy generated by each distributed photovoltaic independently developed in the area is converted into alternating current through an inverter arranged one-to-one with the distributed photovoltaic in the alternating current collection circuit;

[0148] The converted alternating current is collected through the alternating current collection busbar of the alternating current collection circuit.

[0149] Step 2 specifically includes:

[0150] Based on the grid-connected data of the equipment and distributed photovoltaics, the power quality of the distribution network is calculated through the intelligent fusion terminal;

[0151] A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

[0152] Step 3 specifically includes:

[0153] The grid-connected switch of the distributed photovoltaic collection circuit receives and closes based on the control instruction to connect the AC power to the substation of the regional distribution network; or receives and trips based on the control instruction.

[0154] Step 4 specifically includes:

[0155] Obtaining distributed photovoltaic power through the distributed photovoltaic interface of the energy router;

[0156] Obtaining the electric energy demand of the energy storage and the load through the energy storage and load interfaces of the energy router;

[0157] Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load;

[0158] Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

[0159] This embodiment collects and converts the electric energy of several distributed photovoltaics through the cooperation of the collecting bus and the inverter, solves the problem of high difficulty in coordinated control of each inverter in the existing access mode, improves the power quality problem of distributed photovoltaic grid-connected points, and thus reduces the inverter investment and operation and maintenance costs; the collected distributed photovoltaic electric energy is connected to the distribution network through the grid-connected switch, realizing the efficient access of distributed photovoltaics; the collection device proposed in the present invention includes two collection circuits, namely a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit. The DC collection circuit is first collected and then converted into AC power by a unified grid-connected inverter, which can be used for the access of distributed photovoltaics developed in the whole area; the AC collection circuit is first converted into AC power by a one-to-one inverter The method of converting AC power and then collecting it can be used for the access of distributed photovoltaic power developed independently in the region; by connecting the two collected currents in series, it can deal with two development situations at the same time, solving the problem of the singleness of the existing access scheme; through the existing intelligent fusion terminal to monitor the current, voltage and power, and by controlling the closing and tripping of the grid-connected switch, the amount of distributed photovoltaic power entering the grid can be controlled, the power quality can be improved, and the safe operation of the power grid can be ensured; through the energy router with multiple access ports such as photovoltaic, energy storage and load, the photovoltaic power connected to the distribution network is absorbed, which improves the distributed photovoltaic absorption capacity and comprehensive utilization efficiency, realizes the on-site autonomous management of distributed photovoltaic power, and provides a basis for building a multi-level collaborative governance model for power management in the substation area.

[0160] Embodiment 6:

[0161] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in a computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of a control method for a distributed photovoltaic access regional distribution network in the above embodiment.

[0162] Through the storage medium provided in this embodiment, a control method for accessing a distributed photovoltaic power plant to a regional distribution network is implemented. Through the cooperation of a collection bus and an inverter, the electric energy of a number of distributed photovoltaic power plants is collected and converted, thereby solving the problem of high difficulty in coordinated control of each inverter in the existing access method, improving the power quality problem of distributed photovoltaic grid-connected points, and thus reducing the inverter investment and operation and maintenance costs; the collected distributed photovoltaic electric energy is connected to the distribution network through a grid-connected switch, thereby realizing efficient access to distributed photovoltaic power plants; the DC collection circuit is first used to collect the electric energy and then converted into AC power through a unified grid-connected inverter, thereby realizing the access of distributed photovoltaic power plants developed in the entire area; the AC collection circuit is first used to collect the electric energy of the distributed photovoltaic power plants through a one-to-one The inverter is used to convert AC power and then aggregate it, which can realize the access of distributed photovoltaic power developed independently in the region, solving the problem of the singleness of the existing access scheme; the current, voltage and power are monitored by the existing intelligent fusion terminal, and the closure and tripping of the grid-connected switch are controlled to control the amount of distributed photovoltaic power entering the grid, improve the power quality, and ensure the safe operation of the power grid; the photovoltaic power connected to the distribution network is absorbed by the energy router with multiple access ports such as photovoltaic, energy storage and load, which improves the absorption capacity and comprehensive utilization efficiency of distributed photovoltaic power, realizes the on-site autonomous management of distributed photovoltaic power, and provides a basis for building a multi-level collaborative governance model for power management in the substation area.

[0163] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0164] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0165] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0166] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A distributed photovoltaic access regional distribution network collection device, characterized in that: include: Distributed photovoltaic collection circuits connected to regional distribution network stations; The distributed photovoltaic collection circuit is connected to a number of distributed photovoltaics, and is used to collect and convert the electric energy generated by a number of distributed photovoltaics through the cooperation of a collection bus and an inverter; to obtain the current, voltage and power after the electric energy conversion and send them as distributed photovoltaic grid-connected data; and to receive and control the collected distributed photovoltaic electric energy to access the regional distribution network based on control instructions.

2. The distributed photovoltaic access regional distribution network collection device according to claim 1, characterized in that: The distributed photovoltaic collection circuit includes: a grid-connected switch, and one or more of a distributed photovoltaic DC collection circuit and a distributed photovoltaic AC collection circuit; When the distributed photovoltaic is developed in the whole area of ​​the region, the DC collection circuit is connected to a number of distributed photovoltaics developed in the whole area of ​​the region, and is used to collect the electric energy of the distributed photovoltaics developed in the whole area of ​​the region through the collection bus, and convert it into AC power through the inverter; When the distributed photovoltaics are independently developed in the region, the AC collection circuit is connected to a number of distributed photovoltaics independently developed in the region, and is used to convert the electric energy of each distributed photovoltaic into AC power through an inverter set one-to-one with each distributed photovoltaic independently developed in the region, and collect it through the collection bus; The grid-connected switch is respectively connected to the DC collection circuit, the AC collection circuit and the substation of the regional distribution network, and is used to obtain the current, voltage and power converted into AC power and send them as distributed photovoltaic grid-connected data; it is used to receive and close the substation to connect AC power to the regional distribution network based on the control command, or receive and trip based on the control command; Wherein, when a DC collection circuit and an AC collection circuit exist simultaneously in the distributed photovoltaic collection circuit, the DC collection circuit and the AC collection circuit are connected in series.

3. The distributed photovoltaic access regional distribution network collection device according to claim 2, characterized in that: The DC collection circuit comprises: a DC / DC converter, a DC collection bus and a grid-connected inverter; The DC / DC converter is connected to a number of distributed photovoltaic power generation units developed in the entire region, and is used to boost the electric energy generated by the number of distributed photovoltaic power generation units developed in the entire region; The DC collection bus is connected to the DC / DC converter and is used to collect the boosted electric energy; The grid-connected inverter is connected to the DC collection bus and the grid-connected switch respectively, and is used to convert the collected electric energy into alternating current.

4. The distributed photovoltaic access regional distribution network collection device according to claim 2, characterized in that: The AC collection circuit includes: an AC collection bus and inverters equal in number to the distributed photovoltaics; The inverter is connected one-to-one with each distributed photovoltaic power generation unit independently developed in the region, and is used to convert the electric energy generated by each distributed photovoltaic power generation independently developed in the region into alternating current; The AC collection bus is connected to the inverter and the grid-connected switch respectively, and is used to collect the converted AC power.

5. A control device for connecting distributed photovoltaic power to a regional distribution network, characterized in that: include: Energy routers, intelligent fusion terminals and aggregation devices for distributed photovoltaic access to regional distribution networks; The intelligent fusion terminal is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the grid-connected data of the equipment in the regional distribution network area and the grid-connected data of the distributed photovoltaic provided by the collection device; and generating and sending a control instruction to the distributed photovoltaic collection circuit of the collection device based on the grid-connected data of the device and the grid-connected data of the distributed photovoltaic; The energy router is connected to the collection device and the equipment in the regional distribution network area respectively, and is used to obtain the power demand of the equipment in the regional distribution network area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, distribute the distributed photovoltaic power to the equipment for consumption; Wherein, the collection device is the collection device of the distributed photovoltaic access regional distribution network as described in claims 1-4; the equipment in the access regional distribution network station area includes one or more of energy storage and load; The connection mode of the intelligent fusion terminal with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection; the connection mode of the energy router with the equipment in the collection device and the regional distribution network area includes circuit connection and communication connection.

6. The device according to claim 5, characterized in that The intelligent fusion terminal is specifically used for: Calculate the power quality of the distribution network based on the grid-connected data of the equipment and the grid-connected data of distributed photovoltaics; A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

7. The device according to claim 5, characterized in that The energy router includes: interfaces for distributed photovoltaic, energy storage and load; Distributed photovoltaic interface, used to obtain distributed photovoltaic power; The interface between energy storage and load is used to obtain the power demand of energy storage and load; and output the power generated by distributed photovoltaic to energy storage and load.

8. The device according to claim 7, characterized in that The energy router is specifically used for: Obtaining distributed photovoltaic power through the distributed photovoltaic interface; Obtaining the electric energy demand of the energy storage and the load through the interface of the energy storage and the load; Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load; Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

9. A control method for connecting distributed photovoltaic power to a regional distribution network, characterized in that: include: The distributed photovoltaic collection circuit of the control device of the distributed photovoltaic access regional power distribution network is used to collect and convert the electric energy generated by a number of distributed photovoltaics, and the current, voltage and power after the electric energy conversion are obtained and sent as the distributed photovoltaic grid-connected data; Through the intelligent fusion terminal of the control device of the distributed photovoltaic access to the regional distribution network, the grid-connected data of the equipment and distributed photovoltaic in the regional distribution network station area are obtained and the control instructions are sent to the distributed photovoltaic collection circuit of the collection device; Obtaining, through the distributed photovoltaic collection circuit, and connecting the collected electric energy to the substation of the regional distribution network based on the control instruction; The energy router of the control device of the distributed photovoltaic access regional distribution network is used to obtain the power demand of the equipment in the regional distribution network station area and the distributed photovoltaic power provided by the collection device, and based on the power demand of the equipment, the distributed photovoltaic power is distributed to the equipment for consumption; Wherein, the method adopts the control device of the distributed photovoltaic access regional distribution network as described in any one of claims 5-8 to control the distributed photovoltaic access regional distribution network.

10. The method according to claim 9, characterized in that The distributed photovoltaic collection circuit of the control device of the distributed photovoltaic access regional power distribution network collects and converts the electric energy generated by a plurality of distributed photovoltaics, including: When the distributed photovoltaic is developed in the whole area of ​​the region, the DC collection circuit of the distributed photovoltaic collection circuit is used to collect the electric energy of several distributed photovoltaics developed in the whole area of ​​the region by using the collection bus, and the DC is converted into AC by using the inverter; When the distributed photovoltaic is independently developed in a region, the AC collection circuit of the distributed photovoltaic collection circuit is used to convert the electric energy of each distributed photovoltaic into AC power by using inverters that are one-to-one set with each distributed photovoltaic independently developed in the region, and the AC power is collected using a collection bus.

11. The method according to claim 10, characterized in that The DC collection circuit through the distributed photovoltaic collection circuit uses a collection bus to collect the DC power of a plurality of distributed photovoltaics, and uses an inverter to convert the collected DC power into AC power, including: The electric energy generated by a number of distributed photovoltaic systems developed in the entire area is boosted through a DC / DC converter of the DC collection circuit; The boosted electric energy is collected through the DC collection busbar of the DC collection circuit; The collected electric energy is converted into alternating current through the grid-connected inverter of the direct current collection circuit.

12. The method according to claim 10, characterized in that The AC collection circuit of the distributed photovoltaic collection circuit converts the DC power of each distributed photovoltaic into AC power by using an inverter that is set one-to-one with the distributed photovoltaic, and collects the AC power by using a collection bus, including: The electric energy generated by each distributed photovoltaic independently developed in the area is converted into AC electricity through an inverter which is arranged one-to-one with the distributed photovoltaic in the AC collection circuit; The converted alternating current is collected through the alternating current collection busbar of the alternating current collection circuit.

13. The method according to claim 9, characterized in that The intelligent fusion terminal of the control device for connecting the distributed photovoltaic to the regional distribution network obtains and sends control instructions to the distributed photovoltaic collection circuit of the collection device based on the equipment and distributed photovoltaic grid-connected data in the regional distribution network area, including: Based on the grid-connected data of the equipment and distributed photovoltaics, the power quality of the distribution network is calculated through the intelligent fusion terminal; A distributed photovoltaic control instruction is generated according to the calculation result of the power quality of the distribution network, and is sent to the grid-connected switch of the distributed photovoltaic collection circuit.

14. The method according to claim 9, characterized in that The method of obtaining the collected electric energy through the distributed photovoltaic collection circuit and connecting the collected electric energy to the substation of the regional distribution network based on the control instruction includes: The grid-connected switch of the distributed photovoltaic collection circuit receives and closes based on the control instruction to connect the AC power to the substation of the regional distribution network; or receives and trips based on the control instruction.

15. The method according to claim 9, characterized in that The energy router of the control device of the distributed photovoltaic access regional distribution network obtains the power demand of the equipment in the regional distribution network station area and the distributed photovoltaic power provided by the collection device, and distributes the distributed photovoltaic power to the equipment for consumption based on the power demand of the equipment, including: Obtaining distributed photovoltaic power through the distributed photovoltaic interface of the energy router; Obtaining the electric energy demand of the energy storage and the load through the energy storage and load interfaces of the energy router; Based on the electric energy demand of the distributed photovoltaic, energy storage and load, determine the photovoltaic power consumption amount allocated to the energy storage and load; Through the interface between the energy storage and the load, the photovoltaic power consumption is output to the energy storage and the load for consumption.

16. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, a control method for accessing a regional power distribution network to a distributed photovoltaic system as claimed in any one of claims 9 to 15 is implemented.

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