核电站蒸发器水位的二自由度模型驱动控制

Model- driven Two- degree- of- freedom Control for Water Lever of Steam Generator in Nuclear Power Plants

针对核电站蒸发器水位被控对象的非自平衡、非线性等特性,传统PID控制难以获得期望的控制要求,设计了二自由度模型驱动PID(TDF MD PID)串级控制系统,并加入前馈控制,以克服蒸汽流量的影响。该方法通过PD反馈补偿器改善蒸发器水位对象的开环不稳定特性,使其达到稳定,然后进行控制。仿真结果表明,与传统串级PID相比,TDF MD PID结构简单,参数易于整定,具有快速的跟踪能力和很强的鲁棒性,有效地提高了系统的控制性能。

The steam generator system in nuclear power plants has obvious characteristics of non - self -balance and nonlinearity, the conventional PID control is difficult to obtain the desired control perform- ances, the two degree of freedom model driven PID cascade control system is introduced. Besides, in order to overcome the influence of steam flow fluctuation on the water level, a feed - forward compensation is add- ed. In first, TDF MD PID controller using the PD feedback compensator to improve the open - loop unstable characteristic of water lever controlled object for steam generator, which will make it reach a steady state, and then begin to control. The simulation results show that the two degree of freedom model driven PID con- trol system has better control performance than the conventional cascade PID control system. It has the ad- vantages of simple structure, convenient parameter adjustment, quick tracking and strong robustness, which can effectively improve the control performance of processes.