Power factor compensation circuit applied to photovoltaic and energy storage grid connection

Abstract

The utility model discloses a power factor compensation circuit applied to photovoltaic and energy storage grid connection, which comprises an SVG static var generator and a collaborative capacitor module, the SVG static var generator and the collaborative capacitor module are connected in parallel to a power grid, and an external photovoltaic grid connection circuit and an energy storage grid connection are also connected in parallel to the power grid. According to the scheme, the power factor fluctuation in the photovoltaic grid connection scheme can be compensated, the power factor is kept in a relatively stable state as much as possible, and the power factor change caused in the working process of photovoltaic and energy storage grid connection is accurately and quickly adjusted.

Description

Technical Field

[0001] The utility model relates to a photovoltaic grid-connected circuit, in particular to a power factor compensation circuit applied to photovoltaic and energy storage grid-connected circuits. Background Art

[0002] The power generated by photovoltaics will change with the change of light intensity, and the charging and discharging state of energy storage will also dynamically affect the power factor of the grid access point; especially when the photovoltaic power generation is greater than the load power consumption, the active power will be fed back to the mains, and the power factor is measured at the mains voltage meter. In this case, even if the reactive power remains unchanged, the reverse flow of active power may cause the power factor to fail to meet the standard. This solution can accurately handle the power factor failure caused by these special factors brought about by photovoltaic and energy storage grid connection. Utility Model Content

[0003] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a power factor compensation circuit for photovoltaic and energy storage grid-connected systems, which can compensate for power factor fluctuations in photovoltaic grid-connected solutions and keep the power factor in a relatively stable state as much as possible.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a power factor compensation circuit applied to photovoltaic and energy storage grid-connected circuits, comprising an SVG static VAR generator and a cooperative capacitor module, wherein the SVG static VAR generator and the cooperative capacitor module are connected in parallel to the grid, and an external photovoltaic grid-connected circuit and an energy storage grid-connected circuit are also connected in parallel to the grid.

[0005] As a further improvement of the present invention, the SVG static VAR generator and the cooperative capacitor module are both connected to the same transformer and then connected to the power grid.

[0006] As a further improvement of the present invention, the SVG static VAR generator is electrically connected to the cooperative capacitor module so that the cooperative capacitor module can collect power compensation information or power grid information.

[0007] As a further improvement of the present invention, the SVG static VAR generator is further connected to the transformer via a switch.

[0008] As a further improvement of the present invention, the power grid is connected to a plurality of loads, and the plurality of loads are connected to the power grid in parallel.

[0009] As a further improvement of the utility model, the node where the SVG static VAR generator is connected to the transformer is also grounded through a surge protector.

[0010] The beneficial effects of the utility model are that the solution can fully overcome the problem of slow speed and inaccuracy of capacitors in power factor compensation, use the SVG static VAR generator for rapid response and final fine-tuning, effectively combine the defects of capacitors, and make accurate and rapid adjustments to the power factor changes caused by photovoltaic and energy storage grid connection during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is the electrical schematic diagram of the utility model;

[0012] Figure 2 for Figure 1 A partial enlarged view of the

[0013] Figure 3 This is the electrical block diagram of the utility model.

[0014] Figure numbers: 1. SVG static VAR generator; 2. Cooperative capacitor module; 3. Photovoltaic grid-connected circuit; 4. Energy storage grid-connected circuit; 5. Transformer; 6. Surge protector. DETAILED DESCRIPTION

[0015] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.

[0016] Reference Figure 1-3 As shown,

[0017] A power factor compensation circuit applied to photovoltaic and energy storage grid connection includes an SVG static VAR generator 1 and a cooperative capacitor module 2. The SVG static VAR generator 1 and the cooperative capacitor module 2 are connected to the grid in parallel, and an external photovoltaic grid connection circuit 3 and an energy storage grid connection are also connected to the grid in parallel.

[0018] In this solution, the SVG static VAR generator 1 is used in conjunction with the monitoring of grid parameters to respond quickly. When reactive power compensation is required, the power factor in the circuit can be quickly compensated, and the collaborative capacitor module 2 can cooperate in compensation to make the power factor compensation more stable. Thereafter, the SVG static VAR generator 1 is further cooperated to perform fine-tuning compensation. At this time, the SVG static VAR generator 1 can perform fine-tuning compensation in real time to keep the reactive output in a stable power factor state.

[0019] This solution can fully overcome the problem of slow speed and inaccuracy of capacitors in power factor compensation, and utilizes the SVG static VAR generator 1 for rapid response and final fine-tuning, effectively combining the defects of capacitors.

[0020] After ensuring the safety of the working voltage and the circuit, the SVG static VAR generator 1 and the cooperative capacitor module 2 are connected to the same transformer 5 and then connected to the power grid.

[0021] The transformer 5 can isolate the power grid from the SVG static VAR generator 1 and the cooperative capacitor module 2, and can also adjust the voltage to meet the required safe working voltage. When the load is connected to the power grid, it can also produce a certain isolation effect to prevent the load from affecting the operation of the SVG static VAR generator 1 and the cooperative capacitor module 2, which helps to maintain the stability of the power factor.

[0022] In a further preferred solution, the SVG static VAR generator 1 is electrically connected to the cooperative capacitor module 2 so that the cooperative capacitor module 2 can collect power compensation information or grid information.

[0023] The SVG static VAR generator 1 is connected to the cooperative capacitor module 2, which can quickly coordinate the grid parameters and compensation information, so that the cooperative capacitor module 2 can quickly respond to the grid and adjust the power factor.

[0024] The SVG static VAR generator 1 is also connected to the transformer 5 via a switch. The switch is used to facilitate maintenance and on-off control of the SVG static VAR generator 1, and can control the input and disconnection of the reactive power generator module at any time.

[0025] As a further improvement, the node where the SVG static VAR generator 1 is connected to the transformer 5 is also grounded through a surge protector 6. Although the SVG static VAR generator 1 and the cooperative capacitor module 2 can be relatively isolated from the power grid, the surge protector 6 further protects the SVG static VAR generator 1 and the cooperative capacitor module 2, which can further improve the resistance to instantaneous high voltage and prevent the instantaneous high voltage from causing the SVG static VAR generator 1 or the cooperative capacitor module 2 to break down and burn.

[0026] The SVG static VAR generator 1 can also be connected to the power grid through the transformer 5 to collect power grid parameters. The location for signal collection can also be electrically connected to an Internet of Things module, so that the power grid parameters can be sent out for remote monitoring.

[0027] The cooperative capacitor module 2 has a switching switch inside, which can cooperate with the SVG static VAR generator 1 for switching.

[0028] A transformer 5 is provided between the photovoltaic grid-connected circuit 3 and the energy storage grid-connected circuit 4 and the SVG static VAR generator 1 and the cooperative capacitor module 2, so that they can also be isolated to minimize the impact on the SVG static VAR generator 1 and the cooperative capacitor module 2.

[0029] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A power factor compensation circuit for photovoltaic and energy storage grid connection, characterized in that: The invention comprises an SVG static VAR generator and a cooperative capacitor module. The SVG static VAR generator and the cooperative capacitor module are connected to the power grid in parallel, and an external photovoltaic grid-connected circuit and an energy storage grid-connected circuit are also connected to the power grid in parallel.

2. The power factor compensation circuit for photovoltaic and energy storage grid connection according to claim 1 is characterized in that: The SVG static VAR generator and the cooperative capacitor module are both connected to the same transformer and then connected to the power grid.

3. The power factor compensation circuit for photovoltaic and energy storage grid connection according to claim 2 is characterized in that: The SVG static VAR generator is electrically connected to the cooperative capacitor module so that the cooperative capacitor module can collect power compensation information or power grid information.

4. The power factor compensation circuit for photovoltaic and energy storage grid connection according to claim 3 is characterized in that: The SVG static VAR generator is also connected to the transformer via a switch.

5. The power factor compensation circuit for photovoltaic and energy storage grid connection according to claim 3 is characterized in that: The power grid is connected to a plurality of loads, and the plurality of loads are connected to the power grid in parallel.

6. The power factor compensation circuit for photovoltaic and energy storage grid connection according to claim 2, 3, 4 or 5, characterized in that: The node where the SVG static VAR generator is connected to the transformer is also grounded through a surge protector.

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