Voltage reactive comprehensive control method for step transformer substations

Abstract

The invention relates to a voltage reactive comprehensive control method for step transformer substations. Time delays are set in main transformer tap adjustment and reactive compensation capacitor switching control of the transformer substations of different voltage levels, wherein different time delays are set in the main transformer tap adjustment and the reactive compensation capacitor switching control of the transformer substations of the last stage and the main transformer tap adjustment and the reactive compensation capacitor switching control of the transformer substations of the next stage to realize time sequence fit of voltage reactive control of the transformer substations of different voltage levels; the same time delay is set in the voltage reactive control of the transformer substations of the same voltage level; and the operation time delay difference of the transformer substations of different voltage levels is at least greater than the required time of the operation. The method can realize reactive voltage optimization control of a global power grid, and can obviously reduce the ubiquitous problems of frequent main transformer tap adjustment and capacitor bank switching oscillation of the current transformer substations.

Description

technical field [0001] The invention relates to the field of electric energy quality control, in particular to a method for comprehensively controlling voltage and reactive power of cascade substations. Background technique [0002] The improvement of the voltage and reactive power performance indicators of the substation can not only realize power saving, reduce the reactive power output of the generator in the power grid, and reduce the loss of the transmission line, but more importantly, it is related to the safe and stable operation of the power grid. Therefore, in all voltage All grade substations should be able to realize comprehensive control of voltage and reactive power. At present, there are two ways to realize the comprehensive control of voltage and reactive power in substations in the power grid. The voltage and reactive power control device (VQC device) of the substation is used to realize the voltage and reactive power control, and the voltage reactive power c...

AI Technical Summary

Problems solved by technology

At present, there are two ways to realize the comprehensive control of voltage and reactive power in substations in the power grid. The voltage and reactive power control device (VQC device) of the substation is used to realize the voltage and reactive power control, and the voltage reactive power control is realized through the VQC module of the substation comprehensive automation software. Power control, no matter which method is adopted, the control principle is to adopt the traditional nine-area map control strategy. Using the traditional nine-area map control strategy will cause two unexpected situations in practical applications. The first is caused by short-term load disturbances. The second is the continuous adjustment and switching problems caused by the unreasonable coordination of control strategies between the upper and lower levels. Although many ideas have been put forward to solve these two problems , but none of these problems can be solved fundamentally

Although the VQC control device and the VQC software module provide action delay setting function, the correct delay setting can reduce the adjustment actions caused by some short-term disturbance loads, but no one has proposed to realize the comprehensive control of substations with different voltage levels. In the method of time coordination, the electric power department only artificially sets the delay according to the operator's experience, and the action delay of substations with different voltage levels is set to a fixed value, which not only cannot solve the problems of frequent adjustment and switching oscillation, but also causes many other questions

[0003] Therefore, so far, although the voltage and reactive power integrated control software and control devices of substations have set the action delay setting function, but because there is no unified setting method and timing coordination theory of cascade substations, all users have Blindly setting based on experience, without considering the coordination of the setting parameters of the upper and lower levels at all, can not realize the unified control of voltage and reactive power of the global grid substation, and can not solve the problem of frequent adjustment of substation main transformer taps and capacitor switching oscillation

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