执行机构含死区环节的自适应补偿控制

ADAPTIVE AND COMPENSATIVE CONTROL FOR THE EXECUTOR WITH DEAD ZONE

火电厂炉膛负压控制系统中有时含死区类的强非线性环节,死区使该控制回路产生振荡,仅用常规PID控制器无法克服这一现象。为此,该文提出了一种用自适应死区逆对控制回路进行补偿的方法。该方法用描述死区特性的参数构造死区逆来补偿控制器输出;同时又由于死区是未知和时变的,所以用一种鲁棒自适应更新律对死区参数进行在线更新,从而达到用死区逆完全抵消死区影响的目的。仿真试验结果表明,该文的方法几乎能让系统恢复到线性状况,并且死区参数收敛,证明了方法的有效性。

Sometimes the negative pressure control system of boiler in power plant contains a strong nonlinear sector such as dead-zone which makes the system oscillate.The ordinary PID controller can抰 overcome this phenomenon alone. Therefor, a method which uses adaptive dead-zone inverse to compensate the loop is presented in this paper.The dead-zone inverse is formed by the character parameters of dead-zone to compensate the output of controller; at the same time because the dead-zone is unknown and time-variable, we use a robust adaptive update law to update the dead-zone parameters on-line in order to counteract the effect of dead-zone.The result of simulation shows that the methods proposed in this paper can make the system to recover its linearity and the dead-zone parameters are convergent, it is proved that the method proposed is efficient in solving this problem.