计及温控负荷的小干扰稳定性分析

温控负荷是电力系统最为重要的负荷类型之一,它对电力系统的小干扰稳定具有重要的影响。针对这类以恒温控制器控制的负荷（温控负荷）展开研究,通过对恒温控制器动态加热方程的分析,建立用于小干扰稳定分析的温控负荷的数学模型。以3机9节点系统为算例在MATLAB的电力系统分析工具箱（PSAT）中对温控负荷接入电力系统后对系统小干扰稳定影响进行仿真分析。最后以简单的单机无穷大系统为例,进一步分析其负荷参数变化对系统小干扰稳定的影响。仿真分析结果表明：相对于传统的静态负荷温控负荷不利于系统小干扰电压稳定;温控负荷比例控制增益,环境温度,参考温度,对系统的小干扰稳定影响较大;积分控制器增益,积分控制器时间常数,负荷时间常数对系统小干扰稳定性影响较小。

Small disturbance stability analysis considering thermostatically controlled load

Thermostatically controlled load is one of the most important types of electrical power load,which has a significant influence on the small disturbance stability of power systems. A mathematic model of thermostatically controlled load for analysing the small disturbance stability of the power system was constructed based on the dynamic heating equation of thermostat. Using the power system analysis toolbox（PSAT） in MATLAB,a 3-generator 9-bus power system was applied to assess the effect of thermostatically controlled load on the small disturbance stability of the power systems. The influences of the parameters of the thermostatically controlled load on the small disturbance stability was analysed via single-machine infinite-bus system. Simulation results show that compared to the static load model,the thermostatically controlled load has negative influence on power system small disturbance stability. The gain of proportional controller,ambient temperature,reference temperature,time constant of integral controller have considerable influences on the small disturbance stability. The gain of proportional controller,the gain of integral controller and time constant of integral controller have little influence on the small disturbance stability.