Broadband ac-ac power conversion system

Abstract

The utility model aims at providing a wide frequency domain AC / AC power supply system which has simple structure, purification function for power grid and variable output frequency. The utility model system includes the electricity taking CT (2) which takes electricity from the power grid (1), and the AC / DC module (3), the DC / AC module (4) and the three-phase output end (5) are sequentially connected in the rear end of the electricity taking CT (2), the positive line and the negative line between the AC / DC module (3) and the DC / AC module (4) are connected with a plurality of support capacitors (6). The utility model is applied to the power grid technical field.

Description

Technical Field

[0001] This utility model relates to the field of power grid technology, and in particular to a wide frequency domain AC / AC power supply system. Background Technology

[0002] In the energy storage field, energy storage cabinets need to undergo power-on testing before leaving the factory, such as... Figure 1 As shown, energy storage cabinet a is typically tested by connecting it to the high-voltage grid via a power grid converter (PCS). However, due to grid instability, such as voltage harmonics (>5%), voltage instability, and frequency instability, directly connecting the PCS to the grid may lead to inaccurate performance test results for the energy storage cabinet. Furthermore, existing PCS systems are insufficient for testing energy storage cabinets at different frequencies. Therefore, a device is needed that can stabilize the connected grid performance and achieve different frequency outputs to ensure stable operation of the power supplied to the PCS, thereby further guaranteeing the accuracy and frequency coverage of the energy storage cabinet tests. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a wide frequency domain AC-AC power supply system with simple structure, power grid purification function and variable output frequency.

[0004] The technical solution adopted by this utility model is a wide frequency domain AC / AC power supply system, including a power-taking CT that draws power from the power grid. An AC / DC module, a DC / AC module and a three-phase output terminal are sequentially connected to the rear end of the power-taking CT. Several supporting capacitors are connected between the positive and negative lines of the AC / DC module and the DC / AC module.

[0005] The three-phase output terminals are connected in either a delta or star configuration.

[0006] The frequency range of the DC / AC module output is 0 to 1 kHz.

[0007] The beneficial effects of this utility model are as follows: In this utility model, after the power CT is drawn, AC to DC conversion is achieved through the AC / DC module, and DC to AC conversion is achieved through the DC / AC module. The DC voltage is stabilized by the supporting capacitor between the two, reducing the harmonic components of the current and voltage fluctuations, thus improving the stability of the entire system. Furthermore, rectification is achieved through AC / DC conversion, and stable output is achieved through DC / AC conversion, improving the output power quality. This eliminates problems such as voltage harmonics, voltage instability, and frequency instability in the power grid, achieving a purification function for the power grid. The DC / AC module can achieve different frequency outputs, thus meeting different loads and having a wide range of applications. In addition, this power supply system has a simple structure and can eliminate the instability factors in the power grid before outputting power to the PCS, thereby ensuring the detection accuracy of the energy storage cabinet. Attached Figure Description

[0008] Figure 1 This is a simplified structural diagram of an existing energy storage cabinet for testing. Figure 2 This is a simplified structural diagram of the wideband AC power supply system of this utility model. Detailed Implementation

[0009] like Figure 2 As shown, this utility model discloses a wide-frequency AC / AC power supply system, including a power-taking CT2 that draws power from the power grid 1. An AC / DC module 3, a DC / AC module 4, and a three-phase output terminal 5 are sequentially connected to the rear end of the power-taking CT2. Several supporting capacitors 6 are connected between the positive and negative terminals of the AC / DC module 3 and the DC / AC module 4. The three-phase output terminal 5 is connected in a delta or star configuration. The frequency range of the DC / AC module 4 is 0–1 kHz.

[0010] The working principle of this utility model is as follows: The power CT2 draws power from the power grid 1. The AC / DC module 3 converts AC to DC, achieving rectification. After voltage and current stabilization by the supporting capacitor 6, the DC / AC module 4 converts the DC to AC, and then outputs it to the PCS through the three-phase output terminal 5. Finally, the energy storage cabinet connected to the PCS is tested. Testing shows that this invention can control output distortion within 1%, and the frequency range of the DC / AC module 4 output is between 0 and 1 kHz, achieving wide frequency range output. Furthermore, it purifies the power grid before outputting, providing reliable stability for subsequent power output.

[0011] Finally, it should be emphasized that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A wideband AC-AC power supply system, comprising a power-drawing CT (2) that draws power from the power grid (1), characterized in that, An AC / DC module (3), a DC / AC module (4) and a three-phase output terminal (5) are sequentially connected to the rear end of the power CT (2). Several supporting capacitors (6) are connected between the positive and negative lines of the AC / DC module (3) and the DC / AC module (4).

2. The wideband AC-AC power supply system according to claim 1, characterized in that, The three-phase output terminal (5) is connected in either a delta or star configuration.

3. The wideband AC-AC power supply system according to claim 1, characterized in that, The frequency range of the DC / AC module (4) output is 0 to 1KHz.

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