【作者】 钟晖；

【导师】 王明渝；

【作者基本信息】 重庆大学 ， 电气工程， 2003， 硕士

【摘要】 感应电机的无速度传感器矢量控制系统不仅是现代交流传动控制的一个重要研究方向，而且也是研究的热点问题，其核心问题是如何准确地获取电机的转速信息。本文采用在转子磁场定向的条件下，基于全阶磁链观测器的转速估计。因为观测器在估计转速时利用的是电机的额定参数，而电机的参数（定子电阻、转子电阻、励磁电感）由于环境温度的变化、铁心损耗和主磁饱和的影响将发生变化，所以必然有估计误差产生。本文的工作就是研究电机参数变化的影响及其补偿的方法。首先本文研究了在理想电机模型下，感应电机各种参数发生变化时对速度估计的影响。研究后发现定子电阻的影响可以忽略，而转子电阻的变化对速度估计的影响是较大的，因此对转子电阻要进行补偿，一般采用在线辨识的方法。本文利用转速和转子电阻的自适应率对转子电阻的变化进行补偿，仿真结果证明了这种方法的有效性。以往建立感应电机动态数学模型时，通常忽略了电机的铁耗，但在电机中铁耗是真实存在的。对于铁耗的影响，本文建立了考虑铁耗的感应电机仿真模型后，研究了铁耗造成的估计误差，并利用两种方法对误差进行补偿，一种是修改控制器结构的方法，另一种是修改观测器结构的方法，最终都较好地消除铁耗对速度估计的影响。为了验证理论研究的正确性，本文将实验中的电机采样信号（电压和电流）转换为数字量后加在观测器上估计转速，并把结果和实际电机转速作了对比，结果表明稳态下两者很好地一致。更多还原

【Abstract】 Sensorless vector control system of induction motor is not only an important aspect but also a hotspot of investigation in modern AC drive. The key problem is that how we can get the speed of motor accurately.Speed estimation utilized in this paper is based on the way of full order flux observer. The observer makes use of motor parameters to estimate speed, but these parameters (stator and rotor resistance, magnetizing inductance) will vary because of the change of environmental temperature, iron loss and main flux saturation. So parameter variation will lead to the error of estimation, the purpose of this paper is to study the influence and the compensation of parameter variation.Firstly, this paper has discussed the impact of variable parameter variation on speed estimation in the case of idealized motor model and found that the effect of stator resistance can be ignored but the effect of rotor resistance is so large enough that we have to consider the way of compensation which is on-line estimation in common. By using rotor resistance and rotor speed adaptive schemes, rotor resistance variation is compensated effectively which has been proven by simulation.In the past, the establishment of dynamic mathematical model neglected iron loss generally, but iron loss exists truly. After establishing induction motor simulation model with iron loss, this paper has investigated effect of iron loss and proposed two schemes to compensate estimated error due to iron : one modified the structure of controller, the other modified the structure of observer, both schemes eliminated the detuning effect of iron.In order to validate the theoretical investigation, experimental motor sampled signal (the voltage and the current) is conversion to digital quantity and given to observer for estimating speed. The comparative results of estimated speed and actual speed show that both are in good agreement.更多还原