【摘要】 自动发电控制(AGC)调节过程中存在发电机变化率约束、时延等约束条件,使得基于线性模型的AGC控制策略不能反映真实电力系统的频率调节特性。针对AGC时滞系统同时存在饱和与时延的问题,提出了一种基于内外环比例—积分(PI)稳定域的串级控制系统遗传优化策略。基于AGC系统的负荷频率控制与机组控制组成的串级控制回路,采用Hopf分岔代数判据和时滞系统稳定域理论,分别求取了内外回路的PI稳定域,证明了饱和及时延参数会影响到PI稳定域的变化。通过将稳定域转化为控制器参数优化的约束条件后,对内环优化采用不同指标进行对比,证明了绝对误差积分(IAE)指标对于扰动具有更好的抑制能力;而对外环的对比表明采用时间乘平方误差积分(ITSE)指标具有更小的波动量。遗传优化结果表明所提控制策略能够有效抑制饱和及时延环节对系统性能的影响。更多还原

【Abstract】 As there are constraints such as the time delay and generation rate constraint(GRC)in the automatic generation control(AGC)regulation process,the frequency regulation characteristics of power systems cannot be reflected by the AGC control strategy based on linear models.For the saturation and the time delay in the AGC time-delay system,agenetic optimization strategy of AGC cascade control system based on the proportional-integral(PI)stability domain is proposed.AGC system is equivalent to cascade control system made up of load frequency control loop and unit control loop.The Hopf bifurcation algebraic criterion and the time-delay system stability criteria are used to compute the stability domain of the inner and outer loops,respectively.It is proved that the parameters of the saturation and the time delay will affect the PI stability domains.Then the PI stability domains are converted into constraints of controller parameter optimization.Optimization comparative researches for the inner loop have shown that the integral of the absolute error(IAE)index has better performance in suppressing disturbances while the integral of the time squared error(ITSE)index has smaller fluctuations for the outer loop.Genetic optimization results show that the proposed control strategy is able to effectively resist the impact of the saturation and the time delay on the AGC system.更多还原