摘要
水电站多机引水系统复杂供水方式下产生的水力耦合现象导致各机组交互作用,其对电站整体动态特性及调速系统参数整定具有重要影响。相对增益阵列(relative gain array,RGA)是多变量控制系统中各控制变量间交互影响的通用分析方法。该文针对水电站多机水力耦合系统各机组调速控制回路间的交互影响,采用RGA方法对其进行了定量分析。通过建立水电站多机耦合系统整体状态方程,求解系统各调速控制回路间的频域RGA矩阵,揭示了多机耦合系统机组间交互程度在频域内的变化规律,并分析了调压室、岔管等水力系统参数对这种交互的影响。系统时域仿真结果表明了RGA分析方法的可行性及有效性,其分析结果可为水电站多机协调控制策略设计提供依据。
The complex water supply modes in the water diversion system of hydropower plants with multiple units cause interactions among the hydraulic coupling units, which change the dynamic behavior of whole hydro generation system, and have great effects on the control tuning of governors. The relative gain array(RGA) method provides a measure of interactions among control loops in a coupled system. In this paper, RGA method was applied to quantify the control interactions among different units in a hydro-coupled power plant. Based on the state space equation of the whole hydro-coupled generation system, RGA matrix of the coupled system was calculated in frequency domain. Distribution properties of the interactions in frequency domain had been analyzed and influences of the surge tank and the branch penstocks on the degree of such interactions had been proved. Time domain simulations indicate the practicability and effectiveness of the RGA method and these interaction analyses will provide basis for coordinated control design for multi-units in hydro-coupled power plants.
引文
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