基于对称多边形平滑磁链轨迹的直接转矩控制算法

摘要

A direct torque control ( DTC) algorithm based on symmetrical polygon stator-flux locus was proposed with asynchronous traction motors as the research object .By analyzing the excitation current changes , a control algorithm characterized by multiple symmetrical stator-flux trajectories in shape of cir-cle, hexagon or other polygons between them was designed .Smoother stator-flux trajectories were ob-tained and are favorable to improve the harmonic elimination capability and the switching frequency utili -ty.This DTC algorithm is simple in structure and is easy to implement as it only requires adding stator flux regulation to the traditional DTC algorithms .Its effectiveness and feasibility are demonstrated by both theoretical analysis and experimental results .%以异步牵引电机为研究对象，提出了基于对称多边形磁链轨迹的直接转矩控制（ direct torque control， DTC）算法。该算法通过分析励磁电流的变化，设计出一种具备圆形、六边形及两者之间多边形等多种对称磁链轨迹的控制算法，可获得更加平滑磁链轨迹，有利于提高谐波消除能力与开关频率的利用率。所提出DTC算法仅在传统DTC算法的基础结构上添加定子磁链调节算法，不需要复杂计算，因此具有结构简单与容易实现的优点。理论分析和实验结果证明了该控制算法的有效性和可行性。