为实现超导磁储能装置(superconducting magnetic energy storage,SMES)对电力系统功率的准确跟踪与快速补偿,并有效抑制系统的功率振荡,首先分析了包含SMES的单机系统的功角特性,基于系统的能量函数,以提高系统阻尼为目标,提出了以SMES接入点电压及其变化率为控制变量的导纳控制方法数学模型。与传统的以接入点电压幅值或相角做控制变量的控制方法不同,导纳控制方法不仅与接入点电压幅值有关,还与其变化速度有关,因而可提高SMES响应的灵敏度和精度。最后,通过算例验证了SMES抑制单机无穷大系统功率振荡的效果,结果表明该控制方法不仅可以有效抑制功率振荡,而且能使系统迅速恢复稳定状态,从而能提高电力系统的运行稳定性。
To implement accurate power tracking and fast compensation by superconducting magnetic energy storage(SMES) and to suppress power oscillation occurred in power grid,firstly the angle characteristic of a single-machine system including SMES is analyzed;based on the energy function of the power system and taking the system damping as the objective a mathematical model of admittance control approach,in which the voltage and its varying rate at the system-connected point of SMES are taken as the control variable,is proposed.Different from traditional control approach,in which the amplitude or the voltage phase angle is taken as control variable,the proposed admittance control approach not only relates to the voltage amplitude at the system-connected point,but also to its varying rate,thus both the sensitivity and accuracy of the response of SMES can be improved.Finally,the effect of suppressing the power oscillation occurred in single-machine infinite bus system is validated by the results of Matlab/Simulink-based simulation platform.Simulation results show that using the proposed control approach not only the power oscillation can be suppressed effectively,but also the stability of power system can be restoredrapidly,hencethe operation stability of power system can be enhanced.