基于DSP在线实现特定谐波消除技术的2种方法

发布时间：2018-03-14 03:52

本文选题：数字信号处理器　切入点：特定谐波消除　出处：《电力自动化设备》2015年02期 　论文类型：期刊论文

【摘要】：在数字信号处理器中分别用线性插值法和牛顿迭代法实现了特定谐波消除脉宽调制(SHEPWM)技术开关角度的在线计算。首先,利用三角函数倍角关系将级联七电平逆变器SHEPWM消谐方程组转换为代数多项式方程组的形式;然后,利用数学软件MATLAB中的Solve函数对其进行求解得到了调制比区间[0.485,1.07]内的所有解,并绘制了开关角度随调制比变化的轨迹,分析了开关角度变化的特点。选取其中一组开关角度,分别用数据查表结合线性插值的方法和对开关角度进行一元线性拟合并用拟合方程求解的开关角度作为牛顿迭代的初值而后用牛顿迭代法计算开关角度的方法,实现了级联七电平逆变器SHEPWM开关角度的在线计算,对2种方法的特点进行了分析和比较。仿真和实验证明了利用Solve函数求解多项式方程组得到的开关角度解是正确的,所述2种方法是可行的。
[Abstract]:In digital signal processor, linear interpolation method and Newton iteration method are used to realize the on-line calculation of switching angle of special harmonic elimination pulse width modulation (PWM) technique. The SHEPWM harmonic elimination equations of cascaded seven-level inverters are converted into algebraic polynomial equations by using the trigonometric function doubling relation, and then all the solutions in the modulation ratio range [0.485 ~ 1.07] are obtained by using the Solve function in the mathematical software MATLAB. The path of switch angle changing with modulation ratio is plotted, and the characteristics of switch angle change are analyzed. Using the method of data lookup and linear interpolation, the method of linear fitting of switch angle and the switching angle solved by fitting equation are used as the initial value of Newton iteration, and the method of calculating switch angle by Newton iteration method. The on-line calculation of SHEPWM switching angle of cascaded seven-level inverter is realized. The characteristics of the two methods are analyzed and compared. The simulation and experiment prove that the switching angle solution obtained by using Solve function to solve the polynomial equations is correct. The two methods are feasible.
【作者单位】：华东交通大学电气与电子工程学院;
【基金】：国家自然科学基金资助项目(51167006)~~
【分类号】：TM464

【参考文献】