Distributed wind-solar-diesel storage system

Abstract

The utility model discloses a distributed wind-light-diesel storage system which comprises a container, a direct-current diesel generator set, an integrated energy storage device, a fire-fighting and monitoring device, a solar panel, an MPPT inverter device, a wind driven generator and an inverter device. The direct-current diesel generator set is divided into a diesel generator set and a motor controller; the integrated energy storage device adopts a liquid-cooled or air-cooled energy storage cabinet, and a lithium energy storage battery, a battery management device BMS, a PCS energy storage bidirectional converter and an internal heat dissipation device are integrated in the integrated energy storage device; the solar panel and MPPT inverter device comprises a solar panel and an MPPT inverter, the wind driven generator and inverter device comprises a wind driven generator and a fan controller, and the fire-fighting and monitoring device comprises a fire monitoring device, a video monitoring device and an electric energy management device EMS; the utility model has the advantages that the charging and discharging of the energy storage battery can be realized, and the switching between a network construction mode and a network following mode is not needed.

Description

Technical Field

[0001] The utility model relates to an energy storage system, in particular to a distributed wind-solar-diesel storage system, belonging to the field of energy storage systems. Background Art

[0002] The PCS energy storage bidirectional converter is essentially a current source in its grid-following mode. It cannot provide voltage and frequency support on its own and must rely on the grid voltage and frequency, making it unable to support the system. The grid-forming mode is essentially a voltage source, with internally set voltage parameter signals outputting voltage and frequency. It can operate both on and off the grid and has strong grid support capabilities. Existing diesel-storage microgrid systems on the market have shortcomings in practical application, primarily in the control mode of the power supply of the PCS energy storage bidirectional converter and the diesel generator set. The PCS energy storage bidirectional converter requires grid-forming mode to establish stable voltage and frequency when operating independently. However, when the diesel engine is supplying power while simultaneously charging the battery through the PCS energy storage bidirectional converter, the grid-following mode is required. The PCS energy storage bidirectional converter requires shutdown and switching between these two modes.

[0003] (1) There is a power outage during the switching process between the energy storage system and the diesel generator set. This is when the microgrid's power load is relatively large, or the SOC capacity of the energy storage system cannot meet the load needs and needs to switch to the diesel generator set for power supply. The ATS dual power switching system is designed, which will cause a load power outage during the system switching process.

[0004] (2) The PCS energy storage bidirectional converter is connected in parallel with the diesel generator set to output power. When a sudden load change occurs, the load distribution of the two power sources is uneven, causing an impact on the power supply system. The power of both power sources needs to meet the capacity of the load separately, resulting in scale expansion and resource waste. When the load decreases, the diesel generator supplies power to the load and the PCS energy storage bidirectional converter at the same time. The PCS energy storage bidirectional converter needs to switch to grid-following mode when charging. The system control is complex and unsafe, and it is easy to cause the energy storage battery connector to fuse due to fault surge.

[0005] (3) The controllers of the photovoltaic system and wind power generation system are set to grid-connected mode, which can realize parallel power supply with the PCS energy storage bidirectional converter and charge the energy storage system through the PCS energy storage bidirectional converter. Summary of the Invention

[0006] The purpose of the utility model is to design a distributed wind-solar-diesel storage system that can charge and discharge the energy storage battery without switching between grid-building and grid-following modes.

[0007] The technical solution of the utility model is:

[0008] A distributed wind, solar, and diesel storage system, comprising six parts: a container, a DC diesel generator set, an integrated energy storage device, a fire protection and monitoring device, a solar panel and MPPT inverter device, a wind turbine and an inverter device;

[0009] The container serves as the installation location and overall skid assembly for the entire system, allowing the entire device to function as a single unit. The DC diesel generator set is functionally divided into two parts: a diesel generator set and a motor controller. Unlike standard commercially available industrial frequency generators, the diesel generator set outputs an AC frequency of 200-400Hz and utilizes a medium-frequency AC power supply, which reduces device size, improves unit power ratio, and enhances power generation efficiency. The motor controller rectifies the medium-frequency AC power supply from the diesel generator set into DC power, using a constant current mode or a constant voltage mode to charge the lithium energy storage battery of the integrated energy storage device.

[0010] The integrated energy storage device adopts a liquid-cooled or air-cooled energy storage cabinet, which integrates lithium energy storage batteries, a battery management device BMS, a PCS energy storage bidirectional converter, and an internal heat dissipation device, etc.; wherein, the lithium energy storage battery stores DC power, the PCS energy storage bidirectional converter converts DC into AC power to supply power to the load, and rectifies the AC power to DC to charge the lithium energy storage battery; the battery management device BMS is used to monitor the voltage, temperature and other parameters of the lithium battery cell in real time, and manage the battery charging and discharging according to the parameters. Since both charging and discharging generate heat energy, a heat dissipation device is required to control the heat dissipation of the integrated energy storage device;

[0011] The solar panel and MPPT inverter device is designed to fully utilize the solar energy resources at the equipment location. It includes a solar panel and an MPPT inverter. The solar panel is installed on the bottom of the container or on the ground through a bracket. The direct current generated by the solar panel is connected to the MPPT inverter through a cable, which inverts the DC power into industrial frequency AC power and connects it to the AC industrial frequency power distribution cabinet.

[0012] The wind turbine and inverter device are designed to fully utilize the wind resources at the location of the equipment, including a wind turbine and a wind turbine controller. The wind turbine generates electricity and is connected to the wind turbine controller through a cable. The non-power frequency AC power is rectified and inverted into power frequency AC power, which is then connected to the AC power frequency distribution cabinet.

[0013] The fire-fighting and monitoring device is an integrated fire-fighting and monitoring device, including fire monitoring, video monitoring and electric energy management device EMS. The fire-fighting and monitoring device is installed in the power distribution cabinet to effectively manage the overall power supply, control the working status of the PCS energy storage bidirectional converter, start and stop control of the generator set and other functions.

[0014] The container serves as the foundation and protection equipment of the entire equipment and is divided into two compartments: one compartment is equipped with a DC diesel generator set; the other compartment is equipped with an integrated energy storage device and an AC distribution cabinet.

[0015] The solar panel is installed on the top of the container or on the ground around the container, and the wind turbine is installed on the top of the container.

[0016] The diesel generator set provides AC power which is rectified into DC power by the motor controller, and the lithium energy storage battery of the integrated energy storage device is charged in a constant current or constant voltage manner. The electric energy management device EMS provides the SOC capacity and allowable charging power of the lithium energy storage battery through the battery management device BMS to control the output power of the DC diesel generator set; the PCS energy storage bidirectional converter adopts a grid-connected mode to provide AC power to the load, and automatically outputs AC power according to the power demand of the load; the solar MPPT inverter adopts a grid-connected mode, follows the PCS energy storage bidirectional converter to provide power output, and fully utilizes solar energy; similarly, the wind turbine controller adopts a grid-connected mode, follows the PCS energy storage bidirectional converter to provide power output, and fully utilizes wind energy.

[0017] The diesel generator set adopts an axial flux motor with a compact structure, high efficiency, high power density and small size, and can provide electric energy with greater output power in the same installation space.

[0018] The motor controller adopts a high-frequency inverter structure to improve power generation conversion efficiency and reduce the size of the equipment; the motor controller adopts CAN communication to improve the real-time performance of the equipment and achieve higher-precision control of equipment information.

[0019] The electric energy management device EMS adopts CAN protocol, TCP / IP protocol or Modbus_Rtu protocol to automatically collect information of multiple power supply sources, adopts the strategy of giving priority to natural energy and supplementing petrochemical energy to effectively regulate and manage energy, and improve energy utilization.

[0020] The PCS energy storage bidirectional converter always adopts the grid-building mode and does not need to switch to the grid-following mode during charging. This simplifies the control method of the PCS energy storage bidirectional converter, avoids output power failure caused by mode conversion of the PCS energy storage bidirectional converter, and avoids the impact of multiple power supplies. Inrush current improves the safety of the power supply.

[0021] The EMS energy management system monitors real-time load, wind turbine power, photovoltaic power, and the output power of the PCS energy storage bidirectional converter. It also monitors the capacity of the energy storage system. When the energy storage system capacity is insufficient, it controls the diesel generator set to generate power, directly supplying power to the energy storage system through a constant current method. The load AC side still uses the PCS energy storage bidirectional converter to convert DC to AC power.

[0022] The beneficial effects of the utility model are:

[0023] (1) The functions of each energy source in the entire system are fixed, and there is no need for mode switching, which avoids the power outage time of mode switching and meets the high-end requirements of customers for uninterrupted power output;

[0024] (2) Avoiding the load distribution and control of multiple systems, the PCS energy storage bidirectional converter adopts a grid-building mode, automatically stabilizes the voltage and frequency, and automatically adjusts the output power according to the load demand;

[0025] (3) The system capacity margin does not need to be enlarged, saving system equipment investment.

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the external structure of the distributed wind-solar-diesel-storage microgrid system according to an embodiment of the utility model;

[0028] Figure 2 This is a schematic diagram of the internal structure of the distributed wind-solar-diesel-storage microgrid system according to an embodiment of the utility model;

[0029] Figure 3 This is a diagram of the distributed wind, solar, diesel and storage microgrid system in an embodiment of the utility model. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are described below. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. Example

[0031] like Figure 1-3 As shown, a distributed wind, solar and diesel storage system includes six parts: a container 1, a DC diesel generator set, an integrated energy storage device 3, a fire protection and monitoring device, a solar panel and an MPPT inverter device, a wind turbine and an inverter device;

[0032] The container 1 serves as the installation location and overall skid assembly for the entire system, allowing the entire device to function as a single unit. The DC diesel generator set is functionally divided into two parts: a diesel generator set 21 and a motor controller 22 (rectifier controller). Unlike standard commercially available industrial frequency generators, the diesel generator set has an output AC frequency of 200-400 Hz and utilizes a medium-frequency AC power supply, which reduces device size, improves unit power ratio, and enhances power generation efficiency. The motor controller 22 rectifies the medium-frequency AC power supply from the diesel generator set into DC power, which is then used in a constant current or constant voltage mode to charge the lithium energy storage battery of the integrated energy storage device 3.

[0033] The integrated energy storage device 3 adopts a liquid-cooled or air-cooled energy storage cabinet, which integrates a lithium energy storage battery 32, a battery management device BMS, a PCS energy storage bidirectional converter 31, and an internal heat dissipation device, etc.; wherein, the lithium energy storage battery stores DC power, the PCS energy storage bidirectional converter converts DC into AC power to supply power to the load, and rectifies the AC power to DC to charge the lithium energy storage battery; the battery management device BMS is used to monitor the voltage, temperature and other parameters of the lithium battery cell in real time, and manage the battery charging and discharging according to the parameters. Since both charging and discharging generate heat energy, a heat dissipation device is required to control the heat dissipation of the integrated energy storage device;

[0034] The solar panel and MPPT inverter device is designed to fully utilize the solar energy resources at the location of the equipment. It includes a solar panel 51 and an MPPT inverter 53. The solar panel is installed on the bottom of the container 1 or on the ground through a bracket 52. The direct current generated by the solar panel is connected to the MPPT inverter through a cable, which inverts the direct current power into industrial frequency alternating current power and connects it to the AC industrial frequency power distribution cabinet.

[0035] The wind turbine and inverter device are designed to fully utilize the wind resources at the location of the equipment, and include a wind turbine 61 and a wind turbine controller 62 (wind inverter). The wind turbine generator 61 is connected to the wind turbine controller via a cable, rectifies and inverts non-industrial frequency AC power into industrial frequency AC power, and connects to the AC industrial frequency distribution cabinet; the wind turbine generator 61 is installed on the container 1 via a mounting pole 62.

[0036] The fire-fighting and monitoring device is an integrated fire-fighting and monitoring device, including fire monitoring, video monitoring and power management device EMS41. The fire-fighting and monitoring device is installed in the power distribution cabinet to effectively manage the overall power supply, control the working status of the PCS energy storage bidirectional converter, start and stop control of the generator set and other functions.

[0037] like Figure 1The container 1 serves as the foundation and protection equipment of the entire equipment and is divided into two compartments: one compartment is equipped with a DC diesel generator set; the other compartment is equipped with an integrated energy storage device 3 and an AC distribution cabinet;

[0038] like Figure 2 The solar panels are installed on the top of the container 1 or the ground around the container 1 (large photovoltaic), and the wind turbine is installed on the top of the container 1.

[0039] like Figure 3 The diesel generator set provides AC power which is rectified into DC power by the motor controller and charges the lithium energy storage battery of the integrated energy storage device 3 in a constant current or constant voltage manner. The electric energy management device EMS provides the SOC capacity and allowable charging power of the lithium energy storage battery through the battery management device BMS to control the output power of the DC diesel generator set; the PCS energy storage bidirectional converter adopts a grid-connected mode to provide AC power to the load, and automatically outputs AC power according to the power demand of the load; the solar MPPT inverter adopts a grid-connected mode, follows the PCS energy storage bidirectional converter to provide power output, and makes full use of solar energy; similarly, the wind turbine controller adopts a grid-connected mode, follows the PCS energy storage bidirectional converter to provide power output, and makes full use of wind energy.

[0040] The diesel generator set adopts an axial flux motor with a compact structure, high efficiency, high power density and small size, and can provide electric energy with greater output power in the same installation space.

[0041] The motor controller adopts a high-frequency inverter structure to improve power generation conversion efficiency and reduce the size of the equipment; the motor controller adopts CAN communication to improve the real-time performance of the equipment and achieve higher-precision control of equipment information.

[0042] The electric energy management device EMS (CTE601 energy storage controller from Shenzhen Hexin Automation Technology Co., Ltd.) uses the CAN protocol, TCP / IP protocol, or Modbus_Rtu protocol to automatically collect information from multiple power supply sources. It adopts a strategy of prioritizing the use of natural energy and supplementing it with fossil energy to effectively regulate and manage energy, thereby improving energy utilization.

[0043] The PCS energy storage bidirectional converter always adopts the grid-building mode and does not need to switch to the grid-following mode during charging. This simplifies the control method of the PCS energy storage bidirectional converter, avoids output power failure caused by mode conversion of the PCS energy storage bidirectional converter, and avoids the impact of multiple power supplies. Inrush current improves the safety of the power supply.

Claims

1. A distributed wind-solar-diesel-storage system, characterized by: It consists of six parts: container, DC diesel generator set, integrated energy storage device, fire protection and monitoring device, solar panel and MPPT inverter device, wind turbine and inverter device; The DC diesel generator set consists of a diesel generator set and a motor controller. The diesel generator set outputs an AC frequency of 200-400 Hz. The motor controller rectifies the medium-frequency AC power supply of the diesel generator set into DC power, and uses a constant current mode or a constant voltage mode to charge the lithium energy storage battery of the integrated energy storage device. The integrated energy storage device adopts a liquid-cooled or air-cooled energy storage cabinet, which integrates a lithium energy storage battery, a battery management system (BMS), a PCS energy storage bidirectional converter, and an internal heat dissipation device. The lithium energy storage battery stores DC power, and the PCS energy storage bidirectional converter converts DC power into AC power to supply power to the load, and rectifies the AC power to DC power to charge the lithium energy storage battery. The battery management system (BMS) is used to monitor the parameters of the lithium battery cells in real time and manage the battery charging and discharging according to the parameters. The solar panel and MPPT inverter device includes a solar panel and an MPPT inverter. The solar panel is installed on the bottom of the container or on the ground through a bracket. The direct current generated by the solar panel is connected to the MPPT inverter through a cable, which inverts the direct current power into industrial frequency alternating current power and connects it to the AC industrial frequency power distribution cabinet. The wind turbine and inverter device includes a wind turbine and a fan controller. The wind turbine generates electricity and is connected to the fan controller through a cable. The non-power frequency AC power is rectified and inverted into power frequency AC power, which is then connected to the AC power distribution cabinet. The fire protection and monitoring device includes a fire monitoring device, a video monitoring device and an electric energy management device EMS, and the fire protection and monitoring device is installed in a power distribution cabinet.

2. A distributed wind-solar-diesel-storage system according to claim 1, characterized in that: The container serves as the foundation and protection equipment of the entire equipment and is divided into two compartments: one compartment is equipped with a DC diesel generator set; the other compartment is equipped with an integrated energy storage device and an AC distribution cabinet.

3. The distributed wind-solar-diesel-storage system according to claim 2, characterized in that: The solar panel is installed on the top of the container or on the ground around the container, and the wind turbine is installed on the top of the container.

4. The distributed wind-solar-diesel-storage system according to claim 3, characterized in that: The diesel generator set provides AC power, which is rectified into DC power through the motor controller, and charges the lithium energy storage battery of the integrated energy storage device in a constant current or constant voltage manner; the electric energy management device EMS provides the SOC capacity and allowable charging power of the lithium energy storage battery through the battery management device BMS, and controls the output power of the DC diesel generator set; the PCS energy storage bidirectional converter adopts a grid-connected mode to provide AC power to the load, and outputs AC power according to the power demand of the load; the solar MPPT inverter adopts a grid-connected mode, following the PCS energy storage bidirectional converter to provide power output; the wind turbine controller adopts a grid-connected mode, following the PCS energy storage bidirectional converter to provide power output.

5. The distributed wind-solar-diesel-storage system according to claim 4, characterized in that: The diesel generator set adopts an axial flux motor.

6. The distributed wind-solar-diesel-storage system according to claim 5, characterized in that: The motor controller adopts a high-frequency inverter structure; the motor controller adopts CAN communication.

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