摘要
结合磁链轨迹跟踪的PWM生成原理,讨论了一种过调制实现策略。根据实际磁链对期望磁链的跟踪特性,分析建立了相位和径向两类误差模型;结合两类误差模型,定义评价指标:跟踪能力,并由此确定了过调制Ⅰ区和过调制Ⅱ区的分界点;从理论上证明了实现过调制极限状态六阶梯波调制的可行性,并给出其实现条件。开展了仿真验证和样机试验,结果表明新策略能有效提高直流母线电压的利用率,保持从线性调制、过调制Ⅰ区、过调制Ⅱ区直至六阶梯模式的平滑过渡,并明显抑制调制过程中的输出电压总谐波畸变率(THD)。
A overmodulation strategy was studied based on the flux trajectory tracking PWM.First,phase error and radial error were analyzed based on the flux trajectory model.Then,combining two types of error model,a new evaluation for tracking capability was defined,and the demarcation point of overmodulation was determined.Then,the feasibility of six-step operation was proved theoretically,and the achievement conditions of six-step operation was given.Finally,the overmodulation strategy was theoretically analyzed,simulated and experimented.The results show that the new strategy effectually enhance the utilization rate of DC bus voltage and keep smooth transition form linear modulation,overmodulation to six-step operation,and markedly reduce the total harmonic distortion （THD） of the output voltage.
出处
《电机与控制学报》
EI
CSCD
北大核心
2014年第8期105-115,共11页
Electric Machines and Control
基金
国家自然科学基金(51177141)
福建省自然科学基金(2010J01310)
中央高校基本科研业务项目(2010121041)
航空基金(2012ZD68003)
关键词
磁链轨迹
过调制
总谐波畸变率
磁链圆
六阶梯模式
Flux trajectory
overmodulation
total harmonic distortion （THD）
flux linkage circle
six-step operation
