摘要
基于线圈电流闭环控制的智能接触器受到广泛认可,为解决其抗机械扰动和差拍延时控制问题,提出一种自抗扰电流模型预测控制策略。分析线圈电流闭环的扰动机理,探讨不同线圈电压、不同的铁心分离速度对电流上升斜率的影响。分析结果表明,线圈两端电压为零时,线圈电流上升斜率的异常变化与铁心运动速度呈正向关系,由电流上升斜率能够反推铁心的运动状态。建立无差拍的电流数值求解模型,引入感应电动势补偿项,预测下一周期的线圈电流,消除数字控制延时;引入二次型评价函数进行滚动优化,求解最优占空比及开关函数,使接触器受扰动时开关函数为零,自动进入零线圈电压状态观测线圈电流斜率的异常变化,在铁心分离初期自主调节电流设定,从而抑制扰动冲击,接触器吸持状态具有自抗扰能力;该文提出的控制策略同时兼顾稳定吸持时的线圈电流静态误差、纹波,谐波含量低。仿真及实验验证了该控制策略的有效性,提高了智能接触器在新能源领域运行时的吸持稳定性。
The intelligent contactor based on current closed loop control is commonly accepted.In order to solve the disability of mechanical disturbance-resistant and beat delay problem,the active disturbance rejection with current model predictive control strategy is proposed.The mechanism of disturbance to current closed loop is analyzed.The current slope is observed under different coil voltage and core velocity.The anomaly of current rising slope related to iron core speed is proved to infer the motion of iron core under zero coil voltage.The deadbeat model considering induct electric potential compensation is established to predict current and eliminate control delay.The quadratic evaluation function for rolling optimization is introduced to predict optimum duty and switch function.The switch function of zero voltage is automatically set to observe current slope when disturbance happens.The current setpoint is adjusted autonomously and the contactor has the function of active disturbance rejection.Besides diminution of current static error,ripple and harmonic are considered when holding.Related simulation and experiment prove the effectiveness of the proposed strategy.The strategy particularly improve the holding stability of intelligent contactor used in new energy sector.
作者
庄杰榕
许志红
Zhuang Jierong;Xu Zhihong(School of Electrical Engineering Fuzhou University Fuzhou 350116 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2018年第23期5449-5458,共10页
Transactions of China Electrotechnical Society
基金
国家自然科学基金项目(51707039)
福建省科技厅高校产学合作项目(2016H6008)
福建省自然科学基金项目(2017J05076)资助
关键词
自抗扰
预测控制
滚动优化
无差拍
吸持稳定
Active disturbance rejection
predictive control
rolling optimization
deadbeat
holdi ng stability
