Reactive power compensation device and method for distributed photovoltaic power station

Abstract

The invention discloses a reactive power compensation device and method for a distributed photovoltaic power station. The reactive power compensation device for the distributed photovoltaic power station comprises photovoltaic inverters with reactive power adjustability, photovoltaic arrays, a TSC (thyristor switched capacitor), an AVC, a transformer, a load, a low-voltage first busbar and a medium-high voltage second busbar, wherein the photovoltaic inverters, the photovoltaic arrays, the TSC and the load access the first busbar and then are connected to the second busbar through the transformer. The reactive power compensation device and method for the distributed photovoltaic power station have better economic efficiency because total cost of the TSC and the AVC is lower than that of anSVG (static VAR compensator), the power factor of the distributed photovoltaic power station is adjusted for the first time by the TSC, the AVC detects the power factor of the distributed photovoltaic power station in real time by and sends a reactive power adjusting instruction to the photovoltaic inverters, the power factor of the distributed photovoltaic power station is adjusted for the second time by the AVC and the photovoltaic inverters, and the problem that a large quantity of low-order harmonic waves are produced by adopting a TCR (thyristor-controlled reactor) for reactive power compensation is solved.

Description

technical field [0001] The invention belongs to the technical field of power control, and in particular relates to a reactive power compensation device and method for a distributed photovoltaic power station. Background technique [0002] In a distributed photovoltaic power station, in order to ensure the economical operation of transmission lines and transformers, the power supply department will require the power factor of the power station (usually not less than ±0.92). When the power factor does not meet this requirement, it is usually necessary to equip The reactive power compensation device adjusts the power factor to meet the power factor requirements. Reactive power compensation usually uses SVC (static var compensation device) or SVG (static var generator). There are two main ways to apply SVC in distributed photovoltaic power plants: TCR (Thyristor Controlled Reactor) and TSC (Thyristor Switched Capacitor). Continuous capacitive reactive power, the response time ...

AI Technical Summary

Problems solved by technology

However, in the process of reactive power compensation adjustment, TCR will generate a large number of low-order harmonics, and additional filtering devices need to be added. Although TSC will not generate low-order harmonics, because the capacitor bank is switched in stages, it cannot be correct. Accurate compensation of reactive capacity

In addition, although SVG can better solve the above problems, but the cost increases a lot

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