Ong term voltage stability prevention and control method based on time sequence optimal power flow method

Abstract

The invention discloses a long term voltage stability prevention and control method based on a time sequence optimal power flow method; the long term voltage stability prevention and control method comprises the following steps: using a load prediction start point as a prevention point, carrying out line fault screening pretreatment, building a grey load prediction model, and obtaining a predicted load curve in the time period; carrying out preconception accident set screening according to the predicted load curve; employing a system power flow equation minimum modulus characteristic value, in a maximum load Lmax portion of the predicted load curve, to carry out node classification for load node injection variable sensitivity, determining a node voltage to constrain an upper boundary and a lower boundary, and using transmission loss as a target function to do optimal power flow calculation; carrying out super-short term load forecast in the time period of h1-h2 at a new prevention point h1 when the lower time reaches the new prevention point h1. The beneficial effects are that the method provides a voltage state and tendency following control concept, so key load nodes can be monitored, thus making more effective idle balance and voltage safety control measures under heavy load conditions.

Description

technical field [0001] The invention relates to the field of power system operation and control, in particular to a long-term voltage stability preventive control method based on the sequential optimal power flow method. Background technique [0002] The frequent occurrence of power system voltage instability accidents in recent years has brought new challenges to the safe and stable operation of the power system. These accidents are characterized by a relatively long continuous voltage drop process during the development of the accident. In order to prevent the occurrence of long-term voltage instability accidents, it is necessary to formulate reasonable and effective long-term voltage prevention and control strategies. The formulation of the long-term voltage instability prevention and control strategy needs to ensure the accuracy of the calculation and be able to adapt to the requirements of on-line applications. Currently, there is no effective prevention and control str...

AI Technical Summary

Problems solved by technology

In the case of heavy loads, if all node voltages are forced to be within a certain fixed range, it may lead to long-distance transmission of reactive power to ensure the voltage level of some nodes, which will lead to uneven reactive power distribution. balance, and even cause the system to crash

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