【作者】 徐林；

【导师】 张秀彬；

【作者基本信息】 上海交通大学 ， 电力电子与电力传动， 2010， 硕士

【摘要】 电动工具作为一种将电能转化为机械能的设备,被极其广泛地应用于我们生产和生活的各个方面。针对以电机牵引以及驱动系统的调速问题,长久以来一直是电力电子学科中的重要课题。本课题围绕电动工具的动态特性,将电力电子技术和全控开关器件的使用相结合,致力于研究电动工具的轴端输出转矩跟随机械负载变化的自适应控制技术,开发研制出一种具有自适应功能的变频电动工具。为了实现电动工具的自适应控制,文中采用了无速度传感器技术对电动工具的转速进行估算,将估算转速作为反馈变量对转速做闭环调节达到对电动工具速度的控制。在本课题的研究过程中,作者完成了以下工作并取得了一些有实用价值的成果。(1)根据电机在两相静止坐标系中的电压方程和磁链方程,从定子和转子出发可以得到两种形式的转子磁链模型,分别是电流模型和电压模型。电压模型中不含转子速度变量,作为参考模型;电流模型中含有转子速度变量,用作可调模型。以计算得到的电磁转矩作为误差输出,构造出估算转速的模型参考自适应系统。(2)在分析了电动工具对变频调速系统特定要求基础上,提出总体设计思想,完成了系统硬件的设计。主要包括主电路,控制电路以及相应的输入输出电路。(3)在所搭建的硬件平台上,结合软件编程实现了电动工具基于转子磁场的矢量控制调速功能,使得电动工具在负载变化时能够自适应调节转速。(4)最后在Matlab7.1上对系统进行了仿真,分别对转速估算模型和系统的转速性能进行了验证。经验证表明,估算转速能准确跟随实际转速变化而变化,而且系统转速具有较好的稳定性和动态响应。更多还原

【Abstract】 As a machine that can transfer electrical energy into mechanical energy, electrical tool has been used more and more widely in daily life and industrial field. How to change the motor speed according to different load is a very important study subject in power electronics. This article is about how to use power electronictechnique combined with IGBT to build a system that can change the output torque of motor automatically when the load changes.In order to achieve adaptive control of electric tools, sensor-less technology was used to estimate the speed of electric tools, takes the estimate speed as a feedback variable, built a closed-loop speed regulation of electric tools.During the course of this project, the author has completed the following work and achieved some useful results.(1)According to the voltage equations and flux linkage equations of motor in two-phase stationary coordinate system, there are two forms of rotor flux model based on different variables. One is called the current model which contains variable speed and the other one is called voltage model which doesn’t contain this variable. A self-adaptive system with speed estimation model was built by using the calculated electromagnetic torque as the error output.(2)Having analyzed the specific requirements of frequency control system, a design idea was proposed and the hardware design was completed, including main circuit, control circuit and corresponding input and output circuits.(3)Based on the hardware platform, combination of software programming the speed closed-loop adjustment function was achieved. successfully made power tools change adaptively to adjust the load speed.(4)Last but not least, the system was simulated on the Matlab7.1 to test speed estimation model and performance of the system. The results evidenced that estimated speed can vary according to the set speed. At the same time, the system has good speed stability and dynamic response too.更多还原