|
标题：一种高转矩能力的直接转矩过调制控制策略 |
|
作者：车海军，霍丽娇, 王亮亮，等 |
|
| 2017年第12期 访问次数：269次 |
|
摘要：在高速（基速以上）区域，由于逆变器提供的电压有限，异步电机需要工作在弱磁状态。提出一种应用在直接转矩控制（DTC）中的简单过调制策略。该方法作用在电机加速以及高速区域，既扩大了恒转矩范围，提高了转矩能力，又可在弱磁阶段利用六步模型自发削弱磁链值。随着转速的升高，定子磁链轨迹从近似圆形平滑切换到近似六边形。方法的实现是通过修改定子磁链滞环控制器的输出状态。提出的控制策略的主要优点是保持传统DTC的简单结构，不需要电压空间矢量调制。仿真结果证明了该调制策略方法的有效性。
关键词：异步电机；直接转矩控制；高转矩能力；过调制；弱磁
Abstract: At highspeed (above the base speed) region,the induction motor is operated in the field weakening range due to the voltage limit of the inverter.In this paper,a simple overmodulation strategy for direct torque control (DTC) was proposed.This method acted on the motor acceleration and the high speed region,and extended a constant torque region and hence produce high torque capability,utilizing sixmode in the field weakening range to weaken the flux reference.With the angular velocity increasing, controlling the stator flux locus from circular to the hexagonal shape.This method of DTC with the proposed overmodulation strategy was implemented by modifying the error state of the stator flux controller.The main benefit of the proposed method is to maintain the traditional DTC simple structure and does not require a spacevector modulation. Simulation results verify the effectiveness and feasibility of the proposed DTC method.
Key words: induction motor; direct torque control; high torque capability; overmodulation; fieldweakening |
|
| |
|
