交直流混合运行电力系统动态稳定分析中直流准稳态线性化模型的研究

Study of Linearized HVDC Quasi-steady-state Model Used for Dynamic Stability Analysis of AC/DC Hybrid Power System

建立了小干扰动态稳定分析的直流系统准稳态模型线性化方程,并比较分析了直流系统分别采用准稳态线性化模型与直流恒定功率模型对交直流混合运行电网动态稳定的影响。计算结果表明,直流系统准稳态线性化模型可以用于交直流系统低频振荡分析中,而且,在不考虑直流附加控制的情况下,直流系统分别采用准稳态线性化模型和恒定功率模型计算得到的低频振荡特征值差别较小,为简化计算,工程应用时可以采用恒定功率模型来简化直流系统。

The linearized equation of high voltage direct current transmission （HVDC） quasi-steady-state model used for small interference dynamic stability analysis is presented in this paper. The effect of linearized quasi-steady-state HVDC model on the dynamic stability of AC/DC hybrid power system is compared with that of constant-power HVDC model, The computation results show that the linearized quasi-steady-state HVDC model can be applied to low-frequency oscillation analysis of AC/DC hybrid system, and that without additional HVDC controller there is little difference between the lowfrequency oscillation characteristic values obtained by the two models. To simplify the calculation, the constant-power model can be used to simplify HVDC system in engineering application.