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CN-122026451-A - Site power supply system and power scheduling system

CN122026451ACN 122026451 ACN122026451 ACN 122026451ACN-122026451-A

Abstract

The application provides a station power supply system and a power dispatching system, which are applied to the technical field of power dispatching. The station power supply system comprises an alternating current-direct current converter, a current divider, a direct current busbar, a bidirectional direct current-direct current converter, a first battery, a second battery and an air switch. The alternating current input end of the alternating current-direct current converter is used for being connected with a power grid, the direct current output end of the alternating current-direct current converter is connected with a direct current busbar, a first battery is connected with the direct current busbar through a shunt, one end of an air switch is connected with the direct current busbar, and the other end of the air switch is used for being connected with a load. One end of the bidirectional DC-DC converter is connected with the other end of the DC busbar or the air switch, and the other end of the bidirectional DC-DC converter is connected with the second battery. The bidirectional DC-DC converter is used for controlling the charge and discharge of the second battery. Based on this, the charge-discharge statistics of the first battery are not affected, and the influence on the battery management of the first battery can be avoided.

Inventors

  • ZHAI XINYUAN
  • NING FEI
  • CAI YI

Assignees

  • 华为数字能源技术有限公司

Dates

Publication Date
20260512
Application Date
20241107

Claims (10)

  1. 1. The station power supply system is characterized by comprising an alternating current-direct current converter, a current divider, a direct current busbar, a bidirectional direct current-direct current converter, a first battery, a second battery and an air switch; The alternating current input end of the alternating current-direct current converter is used for being connected with a power grid, the direct current output end of the alternating current-direct current converter is connected with the direct current busbar, the first battery is connected with the direct current busbar through the current divider, one end of the air switch is connected with the direct current busbar, and the other end of the air switch is used for being connected with a load; One end of the bidirectional direct current-direct current converter is connected with the direct current busbar or the other end of the air switch, and the other end of the bidirectional direct current-direct current converter is connected with the second battery; the bidirectional DC-DC converter is used for controlling the charge and discharge of the second battery.
  2. 2. The station power supply system of claim 1, wherein the bi-directional dc-dc converter is configured to: controlling the second battery to discharge when the power grid power consumption load is greater than or equal to a first power consumption load threshold value, and controlling the second battery to charge when the power grid power consumption load is less than or equal to a second power consumption load threshold value; The second electrical load threshold is less than the first electrical load threshold.
  3. 3. Station power supply system according to claim 1 or 2, characterized in that the bi-directional dc-dc converter is further adapted to: controlling the second battery to discharge when the electricity price of the power grid is greater than or equal to a first electricity price threshold value, and controlling the second battery to charge when the electricity price of the power grid is less than or equal to a second electricity price threshold value; The first electricity rate threshold is greater than the second electricity rate threshold.
  4. 4. A station power supply system according to any one of claims 1-3, characterized in that the station power supply system further comprises control means for transmitting an indication power to the bi-directional dc-dc converter, which bi-directional dc-dc converter is further adapted to: and controlling the charge and discharge of the second battery according to the indication power sent by the control device.
  5. 5. The site power supply system of claim 4 wherein the indicated power includes a charge indicated power that is the minimum of the dc charge power of the ac-dc converter and the safe charge power calibrated by the second battery.
  6. 6. The site power supply system of claim 4 or 5 wherein the indicated power comprises a discharge indicated power, the discharge indicated power being determined from a product of a calibrated discharge power threshold and a conversion efficiency of the ac-dc converter.
  7. 7. The station power supply system of any one of claims 1-6, wherein the number of cycles of the second battery is greater than the number of cycles of the first battery at the same depth of discharge.
  8. 8. The station power supply system according to any one of claims 1 to 5, wherein a voltage at a terminal of the bidirectional dc-dc converter connected to the dc bus is greater than an output voltage of the ac-dc converter during discharging of the second battery.
  9. 9. A station power supply system according to any one of claims 1-8, characterized in that one end of the bi-directional dc-dc converter is connected to the dc bus via a fuse.
  10. 10. A power dispatching system, characterized in that the power dispatching system comprises a power dispatching center and a site power supply system as claimed in any one of claims 1-9, wherein the site power supply system is used for controlling the charging and discharging of the second battery according to dispatching signals sent by the power dispatching center.

Description

Site power supply system and power scheduling system Technical Field The application relates to the technical field of power dispatching, in particular to a station power supply system and a power dispatching system. Background Along with the proposal of green energy and low-carbon targets, the requirement of the unstable new energy for accessing into a power grid is increased, the requirement of power grid regulation cannot be met only by means of traditional regulating equipment and capacity, and a large risk exists for power grid safety, so that more and more manufacturers search more adjustable load equipment in electricity utilization demand parties through virtual power plants (virtual power plant, VPP) technology, and the regulation effect of the traditional power plants is achieved according to the regulation of the real-time demand of the power grid on the adjustable load. However, for a site power supply system configured with a direct current stack of a lithium battery and a bidirectional direct current-direct current converter, such as a communication site, an energy storage power station, a charging site, etc., the attribution is uniform and the load is stable, and it is often necessary to participate in a power auxiliary regulation service by adding an energy storage battery. However, the existing direct current stacked storage is generally connected to the site power supply system through a battery port of an original energy storage battery of the site power supply system, so that the battery management of the original energy storage battery can be affected in the charging and discharging process of the direct current stacked storage. Accordingly, there is a need to provide a solution to the above-mentioned problems. Disclosure of Invention The embodiment of the application provides a station power supply system and a power dispatching system, which are used for avoiding influencing the battery management of the original energy storage battery of the station power supply system in the process of charging and discharging direct-current stacked storage. In order to achieve the above object, the embodiments of the present application provide the following technical solutions. In a first aspect, an embodiment of the present application provides a station power supply system, where the station power supply system includes an ac-dc converter, a shunt, a dc busbar, a bidirectional dc-dc converter, a first battery, a second battery, and an air switch. The alternating current input end of the alternating current-direct current converter is used for being connected with a power grid, the direct current output end of the alternating current-direct current converter is connected with a direct current busbar, a first battery is connected with the direct current busbar through a shunt, one end of an air switch is connected with the direct current busbar, and the other end of the air switch is used for being connected with a load. One end of the bidirectional DC-DC converter is connected with the other end of the DC busbar or the air switch, the other end of the bidirectional DC-DC converter is connected with the second battery, and the bidirectional DC-DC converter is used for controlling the charge and discharge of the second battery. In the existing site power supply system configured with direct current stacked storage, a bidirectional direct current-direct current converter and an original energy storage battery of the site power supply system are connected with a direct current busbar through a shunt at the same battery port. The current divider is used for carrying out charge and discharge statistics on the original energy storage battery of the direct current stack storage and station power supply system. Under the condition that direct current superposition is not configured, when the electric quantity of the original energy storage battery of the station power supply system is determined to be full according to the statistical result of the current divider, the voltage output by the direct current output end of the alternating current-direct current converter is a floating charge voltage, and the floating charge voltage is a charge voltage set for supplementing self-discharge of the battery. In addition, when the fact that the electric quantity of the original energy storage battery of the station power supply system is too low or the charging current is too large is determined according to the statistical result of the current divider, the voltage output by the direct current output end of the alternating current-direct current converter is automatically converted from floating charging voltage to uniform charging voltage. However, when the original energy storage battery of the bidirectional direct current-direct current converter and the site power supply system is connected with the direct current busbar through the shunt through the same battery port, the shunt can also count the charge and d