Distributed photovoltaic power station regional grid-connected protection system and grid-connected control method

Abstract

The invention discloses a regional grid-connected protection system and a grid-connected control method of a distributed photovoltaic power station. The system is connected between a photovoltaic power station and a transformer, and uses a photovoltaic acquisition / controller, a low-voltage integrated distribution box and a power carrier communication. Central control device; the photovoltaic collection / controller is connected to the inverter of the photovoltaic power station, and is used to collect inverter parameters, transmit the collected parameters to the central control device, receive commands from the central control device, and control the current state of the inverter. Generating power; the low-voltage integrated distribution box is connected to the transformer for collecting transformer parameters and transmitting the collected parameters to the central control device. The central control device collects information in real time, calculates the remaining power of the transformer, and determines the grid-connection requirements according to the current power generation and the minimum adjustable active power of the requested photovoltaic power station, which solves the grid impact caused by the grid-connection of regional distributed photovoltaic power generation systems. issues such as abandoning light, and protecting the operation safety of large power grids.

Description

technical field [0001] The invention belongs to the field of photovoltaic power generation, and relates to a distributed photovoltaic power station, in particular to a regional grid-connected protection system and a grid-connected control method for a distributed photovoltaic power station. Background technique [0002] With the depletion of traditional fossil energy such as coal and oil, and the increasingly serious environmental pollution, the development and application of new energy represented by photovoltaic power generation has become the industry direction guided by the government. At present, the state encourages all kinds of power users to build distributed photovoltaic power generation systems in accordance with the method of "spontaneous self-use, surplus to the grid, and grid regulation". As the number of distributed photovoltaic power generation in a region (such as a village) increases, its power generation exceeds the capacity limit of the upper-level transfo...

AI Technical Summary

Problems solved by technology

As the number of distributed photovoltaic power generation in a region (such as a village) increases, its power generation exceeds the capacity limit of the upper-level transformer or the grid-connected voltage deviation is too large. In this case, all photovoltaic power plants in the region should be disconnected immediately. network, resulting in the phenomenon of large-scale abandoned light

In particular, when distributed photovoltaics are connected to the grid at the same time, an instantaneous voltage rise is generated, causing an instantaneous voltage impact on the large power grid, and there are serious safety hazards

[0003] Distributed photovoltaic power plants are relatively scattered and lack effective comprehensive management and control methods. The problem of grid connection has always been an important problem that is difficult to solve, which determines whether distributed photovoltaics can develop in a reasonable and orderly manner.

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