Voltage control method aiming at 330kV wind power plant collecting transformer substation

Abstract

The invention discloses a voltage control method aiming at a 330kV wind power plant collecting transformer substation. The method comprises the following steps that the wind power plant collecting transformer substation is controlled to carry out voltage out-of-limit judgment; a capacitance reactor of the device in the wind power plant is regulated and controlled; a lower stage executing station carries out longitudinal regulation in the regulation process, so that the voltage control on the wind power plant is completed. On the premise of ensuring the safe and economic operation of an electricity network, the goals of greatly improving the receiving and sending capability of the electricity network on new energy sources, reducing the wind curtailment and improving the new energy online electricity quantity are achieved.

Description

technical field [0001] The present invention relates to the technical field of reactive power and voltage control in the process of large-scale new energy power generation, and in particular to a voltage control method for a 330kV wind farm converging substation. Background technique [0002] Most of the large-scale new energy bases generated after my country's wind power enters the stage of large-scale development are located in the "three north regions" (Northwest, Northeast, and North China). Large-scale new energy bases are generally far away from the load center, and their power needs to be transmitted to load center for consumption. Taking Gansu Power Grid as an example, as of April 2014, the installed capacity of grid-connected wind power in Gansu Power Grid has reached 7.07 million kilowatts, accounting for about 20.2% of the total installed capacity of Gansu Power Grid (35 million kilowatts), becoming the second largest after thermal power. The main power source; the...

AI Technical Summary

Problems solved by technology

At present, the low-voltage tolerance of the wind turbine itself is very limited. At this time, the wind turbine often adopts the method of automatic cut-off for its own protection, which causes the active power imbalance of the system and affects the stability of the system; at the same time, the asynchronous generator does not have the ability to maintain and adjust The ability of the machine terminal voltage level, also absorbs reactive power from the system during operation, so the problem of voltage stability is more prominent

[0004] When the system voltage drops, if the grid cannot provide enough reactive power, the terminal voltage of the wind turbine based on the asynchronous generator cannot be rebuilt, resulting in the removal of the wind turbine by the overspeed protection or low voltage protection action of all the asynchronous wind turbines in the entire wind farm; if The protection cannot operate normally, because the terminal voltage of the wind turbine cannot be rebuilt, which will cause the transient voltage instability of the wind farm and even the regional power grid

Due to the mutual influence between the voltage and frequency of the entire power grid in the AC network system, the large changes in wind power output in Jiuquan area will inevitably cause voltage and frequency fluctuations in the entire system, resulting in further expansion of the accident

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