A comprehensive control device suitable for photovoltaic full generation at the end of low-voltage line of power distribution network

Abstract

The application discloses a kind of comprehensive control device of adaptation power distribution network low-voltage line end photovoltaic full production in the field of power electronics, to solve the problem of consumption caused by large-scale distributed photovoltaic access low-voltage line, the present application includes regional coordination management module, power adjustment circuit module, standardization plug and play interface module, can be used for the voltage comprehensive management of power distribution network low-voltage line of high penetration rate photovoltaic access, with seven big functions of active balance between phases, precise matching of phase impedance, low-voltage line flexible interconnection, mobile energy storage module plug and play, regional photovoltaic panoramic perception, power distribution network end autonomous center and multi-power electronic system resonance management, provide effective solution for the voltage problem of low-voltage line caused by large-scale photovoltaic access.The present application can select distributed energy storage, intelligent reactance, intelligent capacitor, flexible interconnection, distributed photovoltaic control according to demand, with the characteristics of flexible compensation mode, fast regulation speed, rich function etc.

Description

TECHNICAL FIELD

[0001] The application relates to a comprehensive control device for photovoltaic full-load at the end of a low-voltage line of a power distribution network, and belongs to the technical field of power electronics. BACKGROUND

[0002] Distributed photovoltaic power generation refers to a distributed power generation system adopting photovoltaic components to directly convert solar energy into electric energy. The system is a new type of power generation and energy comprehensive utilization mode with broad development prospects. The system advocates the principle of local power generation, local grid connection, local conversion and local use, can effectively improve the power generation capacity of an equal-scale photovoltaic power station, and effectively solves the loss of electric power in voltage boosting and long-distance transportation. Distributed photovoltaic large-scale access to a low-voltage transformer area requires safe, stable and economic operation of the power distribution network. Due to small wire cross section, long power supply radius, large photovoltaic access amount and large source-load time and space difference of the low-voltage transformer area, voltage uplift at the end of the low-voltage transformer area frequently occurs, causing photovoltaic disconnection and serious voltage quality problems, and also causing investment waste. There are many types of distributed photovoltaic inverters, and existing equipment and technology cannot realize communication and control of all photovoltaic inverters, so real-time control of photovoltaic inverter devices cannot be realized. SUMMARY

[0003] The application aims to overcome the deficiencies in the prior art, and provides a comprehensive control device for photovoltaic full-load at the end of a low-voltage line of a power distribution network, to solve the consumption problem caused by large-scale distributed photovoltaic access to a low-voltage line.

[0004] To achieve the above-mentioned purpose, the application adopts the following technical scheme:

[0005] The application provides a comprehensive control device for photovoltaic full-load at the end of a low-voltage line of a power distribution network, comprising:

[0006] A regional coordination management module is used for sending control commands, realizing real-time optimization operation control of the comprehensive control device and managing internal and external communication;

[0007] A power adjustment circuit module is used for receiving and executing the control commands of the regional coordination management module, and automatically distributing circuit power according to real-time tracking control of the control commands;

[0008] A standardized plug-and-play interface module is used for realizing communication of the regional coordination management module with a power distribution network dispatching master station system, a power distribution network fusion terminal, photovoltaic inverters in the region, energy storage BMS and local operation and maintenance PAD, acquiring control data of the power adjustment circuit module, issuing control instructions of the photovoltaic inverters, transmitting control data of the comprehensive control device to the PAD operation and maintenance platform, and receiving operation and maintenance data of the PAD operation and maintenance platform.

[0009] Optionally, the regional coordination management module is at least configured with a regional coordination control algorithm module and a communication module;

[0010] The regional coordination control algorithm module generates scheduling instructions of the power adjustment circuit module and control instructions of the photovoltaic inverters in the region according to a set control target based on data received by the communication module, and issues the instructions through the communication module.

[0011] Optionally, the power adjustment circuit module is at least configured with:

[0012] The local power control board is used to receive control commands of the regional coordination management module.

[0013] The AC / DC energy storage conversion module is used to receive control commands of the local power control board, and realizes three-phase charging and discharging control and three-phase reactive power control of the energy storage in the case of accessing the energy storage BMS, and realizes three-phase reactive power control and three-phase imbalance compensation in the case of not accessing the energy storage BMS.

[0014] The intelligent inductor is used to receive control commands of the local power control board, and is grouped and switched according to demand to absorb inductive reactive power.

[0015] The intelligent capacitor is used to receive control commands of the local power control board, and is grouped and switched according to demand to provide capacitive reactive power.

[0016] Optionally, the standardized plug-and-play interface module is at least configured with a 4G antenna, an HPLC, a LoRa antenna, an RS485 communication plug, a CAN communication plug, Bluetooth, an Ethernet plug, a CT sampling signal plug, an AC quick plug interface, and a DC quick plug interface.

[0017] The 4G antenna is used to communicate with the power distribution network dispatching master station system, and the communication content includes uploading real-time voltage amplitude, current control strategy and parameters, and schedulable capacity of the access point to the dispatching master station.

[0018] The HPLC is used to communicate with the power distribution network fusion terminal to obtain various measurement data of the fusion terminal, which is used to support the integrated control device to generate a dispatching strategy.

[0019] The LoRa antenna is used to communicate with the photovoltaic inverters in the region to obtain real-time status and power generation power of the current photovoltaic, and issues control instructions of each photovoltaic inverter.

[0020] The RS485 communication plug is used for debugging.

[0021] The CAN communication plug is used to communicate with the energy storage BMS.

[0022] The Bluetooth and / or Ethernet plug is equipped with a WIFI module, and is used to communicate with a local operation and maintenance PAD.

[0023] The CT sampling signal is used for collecting low-voltage line three-phase current;

[0024] The AC fast plug-in interface is used for connecting the device to the low-voltage line end in a T type connection mode;

[0025] The DC fast plug-in interface is used for flexible DC interconnection with the integrated control device of other lines or connecting the DC energy storage system.

[0026] The communication module is integrated with at least 4G antenna, HPLC, LoRa wireless, CAN communication plug, RS485, Bluetooth and Ethernet communication mode, and is used for managing the internal and external communication of the regional coordination management module.

[0027] Optionally, the 4G antenna, LoRa wireless and Bluetooth integrated in the communication module are mounted to the shell through an antenna, the CAN communication plug is connected to the shell plug, a group of RS485 is used for internal communication of the local power control board, the HPLC modulates the communication signal to a phase power line, and the Ethernet is connected to the shell plug with another group of RS485.

[0028] Optionally, the control target includes active balance of phase-to-phase electric quantity, accurate matching of phase impedance, flexible interconnection of low-voltage line, plug-and-play of mobile energy storage module, panoramic perception of regional photovoltaic, autonomous center at the end of distribution network and resonance treatment of multiple power electronic systems.

[0029] Optionally, the plug-and-play of the mobile energy storage module adopts a standardized energy interface, and is used for formulating a charge-discharge strategy of the mobile energy storage module, regional peak clipping and valley filling and photovoltaic grounding consumption.

[0030] Optionally, the flexible interconnection of the low-voltage line adopts a standardized DC interface, and is used for flexible interconnection of two end lines with space-time complementary characteristics of loads and photovoltaic.

[0031] Compared with the prior art, the present application has the following beneficial effects:

[0032] The application discloses a kind of comprehensive control device of photovoltaic full production of adaptation distribution network low-voltage line end, including regional coordination management module, power adjustment circuit module, standardization plug and play interface module.Regional coordination management module is used to send control command, realizes the real-time optimization operation control of comprehensive control device and manages internal and external communication.Power adjustment circuit module is used to receive and execute the control command of regional coordination management module, and according to control command real-time tracking control, automatically distributes circuit power.Standardization plug and play interface module is used to communicate with distribution network dispatching master station system, distribution network fusion terminal, regional photovoltaic inverter, energy storage BMS, local operation and maintenance PAD, obtains control data, and issues the control instruction of photovoltaic inverter, transmits the control data of comprehensive control device to PAD operation and maintenance platform, and receives the operation and maintenance data of PAD operation and maintenance platform.The application can solve the voltage problem of large-scale photovoltaic access distribution network low-voltage line, and can select distributed energy storage, intelligent reactance, intelligent capacitor, flexible interconnection, distributed photovoltaic control according to demand, solve the consumption problem caused by large-scale distributed photovoltaic access low-voltage line, with the characteristics of flexible compensation mode, fast regulation speed, rich functions and the like. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 It is the architecture diagram of the comprehensive control device of photovoltaic full production of adaptation distribution network low-voltage line end provided by the embodiment of the application. DETAILED DESCRIPTION

[0034] The technical scheme of the application will be described in detail below with the drawings and specific embodiments, and it should be understood that the specific features in the embodiments and the embodiments of the application are detailed description of the technical scheme of the application, and not the limitation of the technical scheme of the application, and the technical features in the embodiments and the embodiments of the application can be combined with each other without conflict.

[0035] The term "and / or" in this paper is only a description of the association relationship of the associated object, which means that there can be three kinds of relationships, for example, A and / or B can mean that there are three kinds of situations, such as A alone, A and B exist at the same time, and B alone.In addition, the character " / " in this paper generally represents that the front and rear associated objects are a kind of "or" relationship.

[0036] Embodiment one:

[0037] As Figure 1 shown, it is the comprehensive control device of photovoltaic full production of adaptation distribution network low-voltage line end provided by the embodiment of the application, comprising:

[0038] Regional coordination management module: for sending control command, realizing the real-time optimization operation control of comprehensive control device and managing internal and external communication;

[0039] Power adjustment circuit module: used for receiving and executing the control commands of the regional coordination management module, and automatically allocating circuit power according to the control commands in real time;

[0040] Standardized plug-and-play interface module: used for realizing the communication between the regional coordination management module and the power distribution network dispatching master station system, the power distribution network fusion terminal, the photovoltaic inverter in the region, the energy storage BMS and the local operation and maintenance PAD, obtaining the control data of the power adjustment circuit module, issuing the control instructions of the photovoltaic inverter, transmitting the control data of the comprehensive control device to the PAD operation and maintenance platform, and receiving the operation and maintenance data of the PAD operation and maintenance platform. In addition to the plug-and-play in communication, the plug-and-play of the AC / DC primary interface is also included.

[0041] The comprehensive control device for adapting to the full-power generation of photovoltaic at the end of the low-voltage line of the power distribution network provided by the embodiment of the application can solve the voltage problem of large-scale photovoltaic access to the low-voltage line of the power distribution network, and can select and match distributed energy storage, intelligent reactance, intelligent capacitor, flexible interconnection and distributed photovoltaic control according to the demand, solve the consumption problem caused by large-scale distributed photovoltaic access to the low-voltage line, and has the characteristics of flexible compensation mode, fast regulation speed, rich functions and the like.

[0042] The regional coordination management module is at least configured with a regional coordination control algorithm module and a communication module; the regional coordination control algorithm module generates the dispatching instructions of the power adjustment circuit module and the control instructions of the photovoltaic inverter in the region according to the set control target based on the data received by the communication module, and issues the instructions through the communication module.

[0043] The control target includes active balance of interphase electric quantity, precise matching of phase impedance, flexible interconnection of low-voltage line, plug-and-play of mobile energy storage module, panoramic perception of regional photovoltaic, autonomous center at the end of the power distribution network and resonance treatment of multiple power electronic systems.

[0044] The active balance of interphase electric quantity is used for realizing real-time three-phase imbalance judgment, interphase power stepless regulation and avoiding single-phase overvoltage off-network;

[0045] The precise matching of phase impedance can be used for realizing directional matching of phase impedance, precise regulation of end voltage and avoiding bidirectional voltage out-of-limit light abandonment;

[0046] The flexible interconnection of low-voltage line applies a standardized DC interface, and flexibly interconnects two end lines with the time and space complementary characteristics of load and photovoltaic, and is used for realizing photovoltaic mutual aid consumption, low-voltage line overload treatment and dynamic capacity increase;

[0047] The plug-and-play of the mobile energy storage module adopts a standardized energy interface, and is used for realizing the formulation of the charge and discharge strategy of the mobile energy storage module, realizing regional peak clipping and valley filling and photovoltaic grounding consumption;

[0048] The regional photovoltaic panoramic perception obtains real-time state information of all photovoltaics in the region through communication with photovoltaic inverters in the region, and is used for realizing regional photovoltaic power generation prediction and accurate quantification of regional regulation capacity;

[0049] The distribution network terminal autonomous center takes the comprehensive control device as a dispatch center of the low-voltage line, and is used for realizing photovoltaic group control and group regulation, supporting AGC / AVC response, regional energy management and control, and actively supporting distribution network operation.

[0050] The multi-power electronic system resonance suppression performs damping control on the resonance current of each power electronic device of the low-voltage line, and suppresses the resonance of the multi-photovoltaic inverter under a weak power grid.

[0051] The communication module at least integrates a 4G antenna, an HPLC, a LoRa wireless, a CAN communication jack, an RS485, a Bluetooth, and a communication mode of an Ethernet, and is used for managing internal and external communication of the regional coordination management module.

[0052] It should be noted that in the embodiment of the present application, the 4G antenna, the LoRa wireless, and the Bluetooth integrated in the communication module are mounted to the shell through the antenna, the CAN communication jack is connected to the shell jack, one group of RS485 communicates with the internal power control panel, the HPLC modulates the communication signal to a certain phase power line, and the Ethernet is connected to the shell jack with another group of RS485.

[0053] The power adjustment circuit module is at least configured with:

[0054] The local power control panel is used for receiving control commands of the regional coordination management module, and performing real-time control on the AC / DC energy storage conversion module, the intelligent inductor, and the intelligent capacitor.

[0055] The AC / DC energy storage conversion module is used for receiving control commands of the local power control panel, and realizing three-phase charge and discharge control and three-phase reactive power control of the energy storage in the case of accessing the energy storage BMS; and realizing three-phase reactive power control and three-phase unbalanced compensation in the case of not accessing the energy storage BMS.

[0056] The intelligent inductor is used for receiving control commands of the local power control panel, and is grouped and switched according to the demand to absorb inductive reactive power.

[0057] The intelligent capacitor is used for receiving control commands of the local power control panel, and is grouped and switched according to the demand to provide capacitive reactive power.

[0058] Specifically, in the embodiment, the standardized plug-and-play interface module is at least configured with a 4G antenna, an HPLC, a LoRa antenna, an RS485 jack, a CAN communication jack, a Bluetooth, an Ethernet jack, a CT sampling signal jack, an extension unit control signal jack, an alternating current quick plug interface, and a direct current quick plug interface.

[0059] The 4G antenna is used for communication with the power distribution network dispatching master station system, and the communication content includes sending the real-time voltage amplitude of the access point, the current control strategy and parameters, the schedulable capacity, and the dispatching command issued by the dispatching master station to the integrated control device to the dispatching master station

[0060] The HPLC is used for communication with the power distribution network fusion terminal to obtain various measurement data of the fusion terminal, which is used to support the integrated control device to generate a dispatching strategy.

[0061] The LoRa antenna is used for communication with the photovoltaic inverter in the region to obtain the real-time state and power generation power of the current photovoltaic, and issue control instructions to each photovoltaic inverter under the condition of allowing.

[0062] The RS485 navigation plug is used for debugging.

[0063] The CAN communication navigation plug is used for communication with the energy storage BMS.

[0064] The Bluetooth / or Ethernet navigation plug is externally provided with a WIFI module, which is used for communication with the local operation and maintenance PAD, transmits various data of the integrated control device to the operation and maintenance platform on the AD, and receives the operation and maintenance data of the PAD operation and maintenance platform.

[0065] The CT sampling signal navigation plug is used for collecting three-phase current of the low-voltage line.

[0066] The extension unit control signal navigation plug is used for extension of the capacity of the integrated control device. When the compensation capacity is insufficient, the intelligent capacitor and the intelligent inductor are externally expanded, the standard control signal navigation plug is adopted, and the intelligent inductor and the intelligent capacitor externally expanded are dynamically switched according to the treatment demand.

[0067] The AC quick plug interface is used for connecting the device to the end of the low-voltage line in a T-shaped connection mode.

[0068] The DC quick plug interface is used for flexible DC interconnection with other line integrated control devices or DC energy storage systems.

[0069] The comprehensive control device for photovoltaic full-power at the end of low-voltage line of power distribution network provided by the embodiment of the present application can be used for comprehensive management of low-voltage line voltage of power distribution network with high photovoltaic penetration, has seven functions of active interphase power balance, precise matching of phase impedance, flexible interconnection of low-voltage line, plug-and-play of mobile energy storage module, panoramic perception of regional photovoltaic, autonomous center at the end of power distribution network and resonance management of multiple power electronic systems, provides an effective solution for low-voltage line voltage problems caused by large-scale photovoltaic access, can select and match distributed energy storage, intelligent reactance, intelligent capacitor, flexible interconnection and distributed photovoltaic control according to demand, solves the consumption problem caused by large-scale distributed photovoltaic access to low-voltage line, and has the characteristics of flexible compensation mode, fast regulation speed and rich functions.

[0070] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and modifications without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A comprehensive control device adapted to full photovoltaic power generation at the end of a low-voltage line in a power distribution network, characterized in that, The device includes: Regional Coordination and Management Module: Used to send control commands, realize real-time optimized operation control of the integrated control device, and manage internal and external communication; Power adjustment circuit module: used to receive and execute control commands from the regional coordination management module, and to track and control the circuit power in real time according to the control commands, automatically allocating the circuit power; Standardized plug-and-play interface module: used to enable communication between the regional coordination management module and the distribution network dispatch master station system, distribution network fusion terminal, photovoltaic inverters, energy storage BMS, and local operation and maintenance PAD within the region, to obtain control data from the power adjustment circuit module, to issue control commands to the photovoltaic inverter, to transmit control data from the integrated control device to the PAD operation and maintenance platform, and to receive operation and maintenance data from the PAD operation and maintenance platform. The standardized plug-and-play interface module is equipped with at least a 4G antenna, HPLC, LoRa antenna, RS485 connector, CAN communication connector, Bluetooth, Ethernet connector, CT sampling signal connector, AC quick-connect interface, and DC quick-connect interface. The 4G antenna is used to communicate with the power grid dispatching master station system. The communication content includes sending the real-time voltage amplitude of the access point, the current control strategy and parameters, and the dispatchable capacity to the dispatching master station. The HPLC is used to communicate with the power distribution network fusion terminal to obtain various measurement data of the fusion terminal, which is used to support the integrated control device in generating scheduling strategies. The LoRa antenna is used to communicate with photovoltaic inverters in the area to obtain the real-time status and power generation of the photovoltaic system and to issue control commands to each photovoltaic inverter. The RS485 aviation connector is used for debugging; The CAN communication connector is used to communicate with the energy storage BMS. The Bluetooth and / or Ethernet adapter is equipped with an external WIFI module for communication with the local maintenance PAD. The CT sampling signal input is used to collect the three-phase current of the low-voltage line. The AC quick-connect interface is used to connect the device to the end of the low-voltage line in a T-connection manner; The DC quick-connect interface is used for flexible DC interconnection with integrated control devices of other lines or for connection to DC energy storage systems.

2. The integrated control device for achieving full photovoltaic power generation at the end of a low-voltage line in a distribution network according to claim 1, characterized in that, The regional coordination management module is equipped with at least a regional coordination control algorithm module and a communication module. Based on the data received by the communication module, the regional coordination control algorithm module generates scheduling instructions for the power adjustment circuit module and control instructions for the photovoltaic inverters within the region according to the set control objectives, and issues the instructions through the communication module.

3. The integrated control device for achieving full photovoltaic power generation at the end of a low-voltage line in a distribution network according to claim 1, characterized in that, The power adjustment circuit module is configured with at least: Local power control board: Used to receive control commands from the regional coordination management module; AC / DC energy storage conversion module: Used to receive control commands from the local power control board. When connected to an energy storage BMS, it realizes three-phase charging and discharging control and three-phase reactive power control of energy storage; when not connected to an energy storage BMS, it realizes three-phase reactive power control and three-phase imbalance compensation. Intelligent inductors: used to receive control commands from the local power control board, group and switch them according to demand, and absorb inductive reactive power; Intelligent capacitors: used to receive control commands from the local power control board, group and switch them according to demand, and provide capacitive reactive power.

4. The integrated control device for achieving full photovoltaic power generation at the end of low-voltage lines in a distribution network according to claim 2, characterized in that, The communication module integrates at least 4G antenna, HPLC, LoRa wireless, CAN communication connector, RS485, Bluetooth, and Ethernet communication methods for managing communication within and outside the management area.

5. The integrated control device for achieving full photovoltaic power generation at the end of low-voltage lines in a distribution network according to claim 4, characterized in that, The communication module integrates a 4G antenna, LoRa wireless, and Bluetooth, all of which are mounted on the housing via antennas. A CAN communication connector is connected to the housing connector. A set of RS485 devices communicates with the local power control board. HPLC modulates the communication signal onto a certain phase power line. Ethernet and another set of RS485 devices are connected to the housing connector.

6. The integrated control device for achieving full photovoltaic power generation at the end of low-voltage lines in a distribution network according to claim 4, characterized in that, The control objectives include active phase-to-phase power balance, precise phase impedance matching, flexible interconnection of low-voltage lines, plug-and-play mobile energy storage modules, panoramic perception of regional photovoltaic systems, autonomous center at the end of the distribution network, and resonant management of multiple power electronic systems.

7. The integrated control device for achieving full photovoltaic power generation at the end of low-voltage lines in a distribution network according to claim 6, characterized in that, The mobile energy storage module is plug-and-play and uses a standardized energy interface for formulating charging and discharging strategies, regional peak shaving and valley filling, and photovoltaic grounding for energy absorption.

8. The integrated control device for achieving full photovoltaic power generation at the end of low-voltage lines in a distribution network according to claim 6, characterized in that, The low-voltage line flexible interconnection adopts a standardized DC interface, which is used to flexibly interconnect two terminal lines where the load and photovoltaic have spatiotemporal complementary characteristics.

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