Blackstart Of Regional Power System And It's Strategy

More and more recognition has been focused on the blackstart and security ofpower systems because blackouts had taken place frequently in the past few years.Blackstart means restoration from blackout of power systems, in an other word, afterpower system blacks out because of failure, generating units that can restore bythemselves start up without the support of other power system firstly, then assist othergenerating units to start up, and realizes the restoration of the entire power systemfinally. Black start is the last line of defence of the security of the power systems.In order for construction of a proper black start scenario, achievement of fastrecovery and lesser loss, an optimal generating unit set and a logical startup path forblack start of power systems should be decided to solve the problem of reliability andeconomics. And for the constitution of the restoration plan of power systems, muchresearch has to been made about the theory and strategy of black start.This paper dedicates itself to the study on the theory and strategy of black start. Inthe proposed method, according to technical performance index of black start and thecharacteristic of the generators, a mathematical model is presented to simulate thetransmission system, generator, load and frequence response. Then the processcharacteristics of black start of power systems is simulated on the basis of the modeland blackstat rule to analyses the optimal strategy of blackstat by applying thelong-term "quasi static" dynamic emulation mode, then determine the number,capability and location of the generating units in the black start of power systems bycomparison of outage losses and the costs of the start solution. Moreover, this paperrelates to the strategy of black start, involved by the overall strategy of black start,priority analyse of the start-up of generating units and reenergzing transmission line,estimating blackstart duration, restoration strategies of transmission systems and reactive power and voltage control strategies during blackstart. In this paper, the"increase rate of net generating capability" is computed to determined the priority ofthe start-up of generating units, and the "power transmission rate variety index" iscomputed to determined the priority of reenergzing transmission line, and The "threepoint estimation method" is adopted to estimated the time spended in every operationduring blackstart. A delamination and classification restoration strategy oftransmission systems is also proposed in this paper.Eventually, the proposed methods is applied to the blackstart of the guangxipower grid, after analyse systematically and quantitatively the overall strategy ofblack start, selection of initial power source, divisional blackstart strategy, blackstartpaths, start-up sequence of generating units and frequency and voltage controlstrategy during blackstart, a feasible black start scenario is achieved.The results of a simulation case and actual case illustrate that not only theproposed method enhance the stability and security of power systems duringblackstart, but also an optimal scenario of black start results in loss decrease by 30%,time decrease by 40%, and verifies that the proposed method is systemic andeffective.