自动电压调节系统的自抗扰控制

Active Disturbance Rejection Control for Automatic Voltage Regulator System

自动电压调节器(Automatic Voltage Regulator, AVR)的性能往往受到同步发电机高场电感和连续负载变化的影响,电力系统中参数的不确定性对于系统整体性能是一个重大挑战,在设计控制策略时需要重点考虑。线性自抗扰控制(Linear Active Disturbance Rejection Control, LADRC)的显著特点是能够实时估计和消除总扰动,并且不依赖于准确模型。在解决终端电压变化问题时,LADRC是一种可行的解决方案。探讨了三阶线性自抗扰控制器与高阶PID的关系,研究了线性自抗扰控制在AVR电压控制问题中的应用。针对目前AVR中普遍存在的定子电流限制(Stator Current Limit, SCL)问题,提出了一种补偿方案。方案引入发电机理论输出和实际输出的误差作为额外扰动输入,利用扩张状态观测器(Extended State Observer, ESO)对其进行估计,这样可以令线性自抗扰控制器快速补偿误差。仿真证明了与高阶PID相比,LADRC具有更强的抗干扰性,可以取得更好的控制效果。

The performance of the automatic voltage regulator(AVR)is often affected by synchronous generator high field inductance and continuous load changes.The uncertainty of system parameters in power systems is a major challenge to the overall performance of the system,which should be taken into account when designing control strategies.The remarkable feature of linear active disturbance rejection control(LADRC)is that it can estimate and eliminated the total disturbance in time,and does not rely on the accurate model.So LADRC is a practical solution to handle the terminal voltage change problem.In this paper,the application of linear active disturbance rejection control in AVR voltage model control was studied,and the relationship between PIDD controller and third-order linear active disturbance rejection controller was discussed.For the stator current limit(SCL)which is common in AVR at present,a compensation scheme was proposed,using the extended state observer(ESO)to estimate the error of the theoretical output and actual output of generators so that the linear active disturbance rejection controller can compensate the error quickly.Simulation results show that LADRC has better disturbance rejection performance than PIDD and can achieve better control effect.