广域阻尼控制的时滞影响分析及时滞补偿设计

Effect of Delayed Input on Wide-area Damping Control and Design of Compensation

基于相量测量单元技术的广域测量系统使得电力系统向广域监测与控制的方向发展。在这个过程中,信号传输和处理过程中时滞的影响不容忽视。特征值分析表明,时滞τ的影响可以转化为与角频率ω相关的相位滞后和与衰减因子σ相关的增益放大,从而对闭环系统的区间模式阻尼和系统稳定性产生影响。文中利用相位超前／滞后模块和增益调节模块,构成时滞补偿环节,以消除时滞的影响,保证系统的稳定性。通过等值两机系统上的时域仿真,对不同时滞条件下的区间模式阻尼和补偿效果进行了研究。结果表明,所设计的时滞补偿环节能够在一定时滞范围内有效地维持采用远方反馈信号的阻尼控制效果,具有一定的工程意义。

The recent advance in wide-area measurement system （WMAS） is driving power systems to the trend of wide-area monitoring and control. In this trend, the impact of time delays introduced by remote signal transmission and processing in WAMS has to be considered. Eigenvalue analysis demonstrates that delay in time will cause lag in phase with respect to frequency of oscillatory mode and amplification in gain with respect to damping of oscillatory mode. The effect might drive eigenvalues of system matrix to undesirable places on complex plane, and even make power system unstable. Compensation block consisted of lead/lag module and gain module is designed to eliminate the effect of time delay. Simulations in a 2-machine test system are performed to substantiate obtained results and demonstrate the advantage of designed delay compensator when the time delays are within a certain range.