Network source coordination virtual synchronous machine control method of optical storage integrated system

Abstract

The invention discloses a network source coordination virtual synchronous machine control method of an optical storage integrated system. An optical storage integrated system based on the method is ofa two-stage structure. Photovoltaic and energy storage are connected to a power grid by adopting the same inverter, photovoltaic and energy storage batteries are respectively connected to a direct current bus of the inverter in parallel through respective DC / DC converters, and the two DC / DC converters and the inverter are controlled by adopting a network source coordination virtual synchronous machine control scheme. The inverter realizes inertia control and reactive droop control; a DC / DC converter of the battery realizes active droop control; when the voltage of the direct-current capacitoris not higher than the upper limit value Udcuplimit, the photovoltaic DC / DC converter realizes maximum power output control; and when the voltage of the direct current capacitor exceeds the upper limit value Udcuplimit, the photovoltaic DC / DC converter automatically enters light abandoning control. Inertia and droop support can be provided for the power grid, and the power output to the power grid can be automatically adjusted when the source side power fluctuates, so that light abandoning is reduced, and the requirement for the capacity of an energy storage battery is reduced.

Description

technical field

[0001] The invention belongs to the technical field of photovoltaics, energy storage and micro-grid control, and in particular relates to a method for controlling a network source coordination virtual synchronous machine of an integrated system of photovoltaics and storage. Background technique

[0002] In recent years, more and more new energy sources have been integrated into the grid through converters. Initially, new energy sources are connected to the grid with the maximum power output control strategy, so they do not respond to changes in grid-side power demand, which leads to a decrease in grid inertia and poor stability. Therefore, the new energy system is gradually required to have the ability of voltage regulation and frequency regulation and inertial support capability. Therefore, many strategies for controlling new energy grid-connected inverters to provide frequency and voltage support for the grid have been proposed. Among them, VSG has attract...

Examples

Embodiment

[0064] From two aspects of grid-side fluctuation and source-side photovoltaic output fluctuation, the superiority of the control strategy disclosed in the present invention over the control effect of traditional VSG is compared.

[0065] Both strategies are applied to figure 1 Same topology as shown, with same hardware parameters. In the initial state, the battery output current is 0A, and the photovoltaic output power of 1kW is sent to the grid through the inverter. At 0.6s, a sudden -8° phase disturbance on the grid side caused a sudden increase in the absorbed power on the grid side; at 1.2s, the photovoltaic output power began to ramp up (simulated illumination enhancement), and the photovoltaic power rose to 10kW within 0.1s.

[0066] When the traditional VSG control strategy is adopted, the response waveform of the integrated optical storage system is as follows: Figure 5 Shown in (a); when adopting the control scheme disclosed by the present invention, the response w...

technical field

[0001] The invention belongs to the technical field of photovoltaics, energy storage and micro-grid control, and in particular relates to a method for controlling a network source coordination virtual synchronous machine of an integrated system of photovoltaics and storage. Background technique

[0002] In recent years, more and more new energy sources have been integrated into the grid through converters. Initially, new energy sources are connected to the grid with the maximum power output control strategy, so they do not respond to changes in grid-side power demand, which leads to a decrease in grid inertia and poor stability. Therefore, the new energy system is gradually required to have the ability of voltage regulation and frequency regulation and inertial support capability. Therefore, many strategies for controlling new energy grid-connected inverters to provide frequency and voltage support for the grid have been proposed. Among them, VSG has attract...

Examples

Embodiment

[0064] From two aspects of grid-side fluctuation and source-side photovoltaic output fluctuation, the superiority of the control strategy disclosed in the present invention over the control effect of traditional VSG is compared.

[0065] Both strategies are applied to figure 1 Same topology as shown, with same hardware parameters. In the initial state, the battery output current is 0A, and the photovoltaic output power of 1kW is sent to the grid through the inverter. At 0.6s, a sudden -8° phase disturbance on the grid side caused a sudden increase in the absorbed power on the grid side; at 1.2s, the photovoltaic output power began to ramp up (simulated illumination enhancement), and the photovoltaic power rose to 10kW within 0.1s.

[0066] When the traditional VSG control strategy is adopted, the response waveform of the integrated optical storage system is as follows: Figure 5 Shown in (a); when adopting the control scheme disclosed by the present invention, the response w...

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