A system for handling redundant power supply of energy storage inverters

Abstract

This utility model relates to the field of energy storage inverter technology, specifically disclosing a system for handling redundant power supply in an energy storage inverter. The system includes an energy storage inverter, a bridge rectifier circuit, an isolation transformer, an AC power grid, and a battery. The first input side of the energy storage inverter is directly connected to the battery, and the second input side of the energy storage inverter is connected to the AC power grid sequentially through the bridge rectifier circuit and the isolation transformer. A high-voltage power supply is provided in the energy storage inverter. The battery outputs a first DC power, and the AC power grid outputs a first AC power. The isolation transformer converts the first AC power to a second AC power. The bridge rectifier circuit converts the second AC power to a second DC power before outputting it to the high-voltage power supply. The voltage of the first DC power is lower than the voltage of the second DC power. The system provided by this utility model for handling redundant power supply in an energy storage inverter can reduce the power consumption of the battery in the energy storage system and meet insulation performance requirements.

Description

Technical Field

[0001] This utility model relates to the field of energy storage inverter technology, and more specifically, to a system for handling redundant power supply of energy storage inverters. Background Technology

[0002] Energy storage inverters possess bidirectional operating characteristics, allowing them to function when either AC or DC power is available. Under this technological premise, energy storage inverters are required to have a startup function when only one power source is available (e.g., the system is powered only by DC or only by AC). Currently, the problem with dual power supply systems used in energy storage inverters is that the internal power supply system continuously consumes battery pack power when the machine is in standby or running.

[0003] The most common solution to the above problems is to use AC / DC redundant power supply for the built-in power supply of the energy storage inverter. The functional implementation steps are as follows: the built-in power supply of the energy storage inverter is a DC power supply. (1) When only DC power supply is available, the built-in power supply can work directly and convert the voltage required by the machine. (2) When only AC power supply is available, there is a rectifier bridge circuit between the AC power supply back end and the built-in power supply front end to rectify the AC power into DC power to supply the built-in power supply. (3) When both AC and DC power supplies are available, the built-in power supply is powered by both AC and DC. The AC power supply of the built-in power supply in the prior art is usually directly supplied by the power grid. The disadvantage is:

[0004] (1) Increased battery energy consumption (increased system cost): When AC and DC power are supplied simultaneously, the DC side voltage is usually higher than the grid side voltage. At this time, the power consumption of the built-in power supply is usually provided by the DC side, which will increase the power consumption of the battery in the energy storage system.

[0005] (2) Insufficient insulation level: When AC and DC are supplied at the same time, it is equivalent to AC and DC only being in contact through semiconductors, which usually does not meet the technical application requirements of basic insulation. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a system for handling redundant power supply in energy storage inverters, which can reduce the power consumption of batteries in energy storage systems and meet insulation performance requirements.

[0007] As a first aspect of this utility model, a system for handling redundant power supply of an energy storage inverter is provided, comprising an energy storage inverter, a bridge rectifier circuit, an isolation transformer, an AC power grid, and a battery. The first input side of the energy storage inverter is directly connected to the battery, and the second input side of the energy storage inverter is connected to the AC power grid in sequence through the bridge rectifier circuit and the isolation transformer. The energy storage inverter is equipped with a high-voltage power supply. The battery outputs a first DC power, and the AC power grid outputs a first AC power. The isolation transformer is used to convert the first AC power into a second AC power. The bridge rectifier circuit is used to convert the second AC power into a second DC power and output it to the high-voltage power supply. The voltage of the first DC power is lower than the voltage of the second DC power.

[0008] Furthermore, the bridge rectifier circuit includes an AC / DC converter.

[0009] The system provided by this utility model for handling redundant power supply of energy storage inverters has the following advantages:

[0010] (1) Save battery power: An isolation transformer is added between the AC grid and the inverter’s built-in power supply. The isolation transformer has the function of regulating voltage. When AC and DC are supplied at the same time, the AC side voltage is higher than the DC side voltage after rectification. At this time, the power consumption of the built-in power supply will not be provided by the DC side, which will reduce the power consumption of the battery in the energy storage system.

[0011] (2) Meets insulation performance requirements: When AC and DC are supplied at the same time, it is equivalent to adding an isolation transformer for electrical isolation between AC and DC, which not only has semiconductor barrier, but also meets insulation requirements. Attached Figure Description

[0012] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the following detailed description to explain the present invention, but do not constitute a limitation thereof.

[0013] Figure 1 The schematic diagram of the system provided by this utility model for handling redundant power supply of energy storage inverters.

[0014] Figure 2 The flowchart of the system provided by this utility model for handling redundant power supply of energy storage inverters. Detailed Implementation

[0015] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a system for handling redundant power supply of an energy storage inverter according to this utility model. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0016] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0017] In explaining this utility model, it should be noted that the terms "installation," "connection," and "linking" should be interpreted broadly unless otherwise specified. For example, a connection can be a fixed connection, a connection through a special interface, or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0018] This embodiment provides a system for handling redundant power supply of energy storage inverters, such as... Figure 1 As shown, the system for handling redundant power supply of the energy storage inverter includes an energy storage inverter, a bridge rectifier circuit, an isolation transformer, an AC power grid, and a battery. The first input side of the energy storage inverter is directly connected to the battery, and the second input side of the energy storage inverter is connected to the AC power grid in sequence through the bridge rectifier circuit and the isolation transformer. The energy storage inverter is equipped with a high-voltage power supply. The battery outputs a first DC power, and the AC power grid outputs a first AC power. The isolation transformer is used to convert the first AC power into a second AC power. The bridge rectifier circuit is used to convert the second AC power into a second DC power and then output it to the high-voltage power supply. The voltage of the first DC power is lower than the voltage of the second DC power.

[0019] Preferably, the bridge rectifier circuit includes an AC / DC converter.

[0020] It should be noted that the energy storage PCS is an energy storage inverter.

[0021] like Figure 2 As shown, the system provided by this utility model for handling redundant power supply of energy storage inverters has the following working process: the battery outputs 1130V DC power, the AC grid outputs 400V AC power, the isolation transformer converts the 400V AC power output from the AC grid to 800V AC power; the bridge rectifier circuit converts the 800V AC power to 1131V DC power. Since the 1130V DC power output from the battery is always lower than the 1131V DC power supplied by the AC grid, the high-voltage power supply in the energy storage inverter is always supplied by the AC grid, thus achieving the result of not consuming battery power.

[0022] For example: Typically, the maximum power of the built-in high-voltage power supply in an energy storage inverter is 150W-200W, with the operating power generally maintained at 120W. Therefore, the power consumption per hour is 0.12kWh. If a user charges the battery from 10 PM to midnight, and then the energy storage inverter shuts down until 8 AM, following traditional technology, the built-in high-voltage power supply will consume 0.12 × 8 = 0.96kWh during the downtime. This means that the actual capacity of the battery in the energy storage system each morning is [amount missing]. The amount of electricity consumed will be about 1 kWh less than the full capacity. If the total battery capacity in the energy storage system is 300 kWh, the actual application capacity is only 299 kWh. Furthermore, if the original scheme is followed, the energy storage inverter will consume battery power for the entire operating time. Assuming that the energy storage inverter actually operates for 16 hours a day, the power consumption is 1.92 kWh. 1.92 kWh of battery power will not be output to external devices. This scheme can effectively prevent the battery from consuming this part of the power by changing the power supply method.

[0023] Therefore, the present invention provides a system for handling redundant power supply of energy storage inverters, (1) saving battery power: an isolation transformer is added between the AC grid and the built-in power supply of the energy storage inverter PCS. The isolation transformer has the function of regulating voltage. When AC and DC are supplied at the same time, the AC side voltage is rectified and the input voltage is higher than the DC side voltage. At this time, the power consumption of the built-in power supply will not be provided by the DC side, which will reduce the power consumption of the battery in the energy storage system; (2) meeting the insulation performance requirements: when AC and DC are supplied at the same time, it is equivalent to not only semiconductor barrier between AC and DC, but also adding an isolation transformer for electrical isolation, which meets the insulation requirements.

[0024] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A system for handling redundant power supply of energy storage inverters, characterized in that, The device includes an energy storage inverter, a bridge rectifier circuit, an isolation transformer, an AC power grid, and a battery. The first input side of the energy storage inverter is directly connected to the battery, and the second input side of the energy storage inverter is connected to the AC power grid in sequence through the bridge rectifier circuit and the isolation transformer. The energy storage inverter is equipped with a high-voltage power supply. The battery outputs a first DC power, and the AC power grid outputs a first AC power. The isolation transformer is used to convert the first AC power into a second AC power. The bridge rectifier circuit is used to convert the second AC power into a second DC power and then output it to the high-voltage power supply. The voltage of the first DC power is lower than the voltage of the second DC power.

2. The system for handling redundant power supply of energy storage inverters according to claim 1, characterized in that, The bridge rectifier circuit includes an AC / DC converter.

Images