【作者】 乔理峰；

【导师】 顾伟；

【作者基本信息】 上海海事大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 三相中压异步电动机广泛用于工矿企业、交通运输和国防工业等国民经济各个领域的机械设备中，使用量大、范围广。而中压异步电动机的直接起动会产生很大的起动电流，一般可达额定电流的5～7倍，最大可达15倍。为了解决上述的问题，本论文研究的设备采用降压起动的方式来减小起动电流，采用开关变压器一次侧连接电动机定子，二次侧与晶闸管串联。本论文研究的中压异步电动机电压等级为6kv～10kv。 本论文系统介绍了软起动器的发展概况，尤其是中压软起动装置，详细介绍了开关变压器的原理、基于开关变压器的中压软起动的起动性能，并针对起动状况的分析，提出了模糊控制软起动策略。对于电动机起动需要控制起动电流和转矩震动的问题，采用双闭环的控制方案，即电流闭环控制和功率因数角闭环控制。电流闭环控制起动电流，而功率因数角闭环控制是减轻电机起动时转矩震荡的问题。设计相关的软件和硬件，并在现场和实验室进行产品试验，拍摄了大量相关波形。在本论文中，给出了大量的实验拍摄波形。 本论文第二章从理论上分析和研究了开关变压器的工作原理，给出了开关变压器的数学模型，推导出开关变压器的等效电抗；在第三章中分析了基于开关变压器的中压软起器起动性能，并通过了MATLAB仿真加以验证；第四章主要介绍了软起动模糊控制策略和实现；第五章给出了软起动控制器主要的硬件电路和软件设计；第六章给出了基于开关变压器软起动器的试验波形和分析。更多还原

【Abstract】 Asynchronous motor is largely used in the fields of industry, transportation and others. In these fields, middle-voltage asynchronous motor has big requirements. Buts, it will produce big current when starting directly; usually the current can reach 5-7 times of nominal, sometimes the current even reach 15 times. In this paper, the soft-starter is based on the transformer so that it can work under the middle voltage. In order to avoid the high voltage and reduce the starting current, a pair of anti-parallel SCR is to be connected with the second winding of the transformer and the primary winding is directly connected with the motor’s stator.The appliance which is researched in this paper can work at the range of voltage which is 6kv-10kv.In this paper, the development of the soft-starter is introduced in detail, especially for the middle-voltage one. Besides the introduction of the theory of the on-off transformer and the characteristic of middle-voltage starter, the method of control according to the fuzzy is pointed out. As for the problem the high current and the vibration of the torque, the double closed loops which include the current and power factor angle are worked out. With the using of the loop of the current, the current of starting can be controlled efficiently. At the same time, the problem of vibration is reduced more or less under the working of the power factor angle loop.Based on the understanding of the starter, the associated software and hardware are designed. Meanwhile, the function of these can satisfy the requirements of the working situation after the experiment. In order to improve these, there are many pictures put in the paper which are taken in the lab and the working station.At the beginning of this paper, the theory of the on-off transformer is discussed and the mathematic model of it is gotten. On the basis of these fruits, the更多还原