The Mechanism And Game Analysis Of Multi-level Power Grids’ Voltage Control Mismatch

Since the power systems interconnection have further developed, electric connectionbetween various regions become increasingly complex and electromagnetic loop becomesmore and more general in the operation. Volt/var control problem in power system is not onlythe optimal control problem in the region, but also need to give consideration to thecoordination and control problem between regions of the same level and the upper and lowerlevel. It will be great importance to dispatch department how the multi-level dispatch centersoptimize reactive voltage coordination.This thesis firstly reviews the practical experience and researches on volt/var control andcoordination of power system. It analyzes and summarizes the problems through the researchstatus on the volt/var control and coordination of home and abroad power system. Thus, itsummarize and define the ideal state of the volt/var control in power system, and the conceptof uncoordinated volt/var control is proposed to meet the conditions of adaptabilityrequirements for ideal state, which is used to study the characteristics of coordinated control.Based on the above analysis, this thesis analyzes the coordinated control problem from threedimensions of space, time and objectives, builds up the equivalent analysis of mathematicalmodel, proposes the analysis system of uncoordinated control.This thesis proposes a thought of volt/var optimal control which is against the limitationsof implementation and control in the traditional large scale grid on reactive poweroptimization. By studying on the volt/var variation characteristics of optimal flow combiningwith the features of AVC/VQC controls, it builds a model without basing on the completelarge grid but according to the given regulation strategies and parameter tuning to carry outlogic trigger control, guide the regional or site volt/var controls, that is the theoreticalpreparations to raise the thought and strategy on solving the uncoordinated control problem.This thesis introduces the game theory to reveal the essence of multi-level voltagecontrol mismatch of large scale grid, establishes cooperative game model and non-cooperativegame about control coordinated problem. At last it expounds and proves the effectivenessabout using cooperation mechanism to solve the control mismatch problem by Nashequilibrium. In the simulation example, this thesis, through the complete analysis flow, analyzes thedirect, indirect and basic reason in various types of typical control mismatch problem. itanalyses the "rational man" role in control mismatch subjects by game theory, and then a newcontrol constraint based on the thought of controlling the volt/var trend to the optimum isintroduced into cooperation game mechanism. That verifies the effectiveness of this kind ofcontrol, proves that the analysis in this thesis is a new idea to solve the volt/var controlmismatch problem of multi-level power grids.