一种组合型中点SPWM采样方法的研究  

On a combined-midpoint SPWM regular-sampling approach

作　　者：朱其新[1,2] 陈健亨[2] 胡寿松[3] 

机构地区：[1]苏州科技学院机械工程学院,江苏苏州215009 [2]华东交通大学电气与电子工程学院,江西南昌330013 [3]南京航空航天大学自动化学院,江苏南京210016

出　　处：《电机与控制学报》2014年第12期72-78,94,共8页Electric Machines and Control

基　　金：国家自然科学基金(51375323;61164014);江苏省"青蓝工程"

摘　　要：提出一种组合型中点不对称规则采样法,只需在三角载波的波峰(或波谷)进行采样,利用数学中线性组合的原理构造出波谷(或波峰)的"采样点",再根据二分法的原理求得SPWM波开关点的时刻值。详细阐述了该方法的基本理论,并得出产生SPWM波开关点的运算方程。理论分析与仿真研究表明,与传统的规则采样法相比,该方法的SPWM算法更简单,采样点更少,开关点时刻值的误差和负载电流THD更小,且输出的基波幅值更大。所以,该方法对传统的规则采样法进行了优化,更加逼近了自然采样法的调制效果,易于在DSP上实现,并且运算速度快,具有良好的工程应用价值。A combined-midpoint-asymmetric-regular-sampling approach was proposed. It only needs to sample at crests（ or troughs） of the triangular-carrier wave,and then the principle of mathematical linear-combination was used to construct the sampling points of troughs（ or crests）,and then,according to the principle of dichotomy to get the time values of the switch point. The basic theory of the proposed method was described and the operational equation of SPWM switch time was given. Theory analysis and simulation study show that,the proposed SPWM algorithm is more simple,the sampling point is less,errors of the switch point＇s time values and the THD of load current are smaller,and the fundamental amplitude output is bigger than that of the traditional regular-sampling. Therefore,the traditional regularsampling algorithms were optimized by the proposed algorithm,which is easy to achieve in the DSP,with high speed,and have a good engineering application value.

关 键 词：SPWM 组合型中点式 不对称 规则采样法 THD 

分 类 号：TM46[电气工程—电器]