高精度正余弦函数FPGA实现(打印).pdfVIP

高精度正余弦函数的FPGA实现 陈海波 (巢湖学院 物理与电子科学系，安徽 巢湖 238000) 摘 要：近年来，由于电力电子的发展，电力电子方面大功率可控整流、变频调速设备的广范 应用使得电力系统的稳定运行存在严重的隐患，使得谐波的检测和补偿抑制受到关注，其中任意次 谐波的准确检测在于如何准确的设立正余弦函数的频率。因此如何利用最少的ROM资源在最短的时 延之内产生高精度的正余弦函数成为了需要解决的首要问题。随着研究的深入，不断的产生了多种 算法如：cordic算法、查找表法、插值法。查找表法是根据精度要求产生函数值存储器，构成正 弦表；cordic （坐标旋转数字计算机算法）算法是由J.Volder于1959年提出的应用计算三角函数 等方法通过迭代满足精度的串行实现方法；线性插值法是选择合适的基点值，在基点上进行线性插 值。本文就上面三种方法进行比较，用硬件描述语言VerilogHDL描述三种算法的正余弦函数实现， 其次利用VCS仿真软件，得到其仿真后输出的时序波形结果并对其作出说明，得出线性插值法实现 正余弦函数的优点，最后把仿真成功的程序下载到现场可编程门阵列 （FPGA）中进行实现。 关键词：函数；FPGA；算法；时延；面积 ImplementationofHighAccuracy SineandCosine FunctionBasedonFPGA Chen Haibo (Department ofPhysicsandElectronic Science,Chaohu College,Chaohu Anhui238000) Abstract: In resent years, Because the development of Power Electronic, the electric power electronics big power can control to commutate, velometer and transducer be used in widely, so many severity hidden questions in electric system, Make harmonic examination and repair repress to be subjected to concern, Among them arbitrarily the time harmonic accurate examination lie in how to accurately establish the frequency ofpositive cosine function.Consequently how makeuseoftheminimal ROM resources at the shortest of postpone inside produced the positive cosine function of high accuracy to become the initial problem that needs to be solved. Along with research of thorough, continuously produced various calculate ways for example: cordic algorithm, linera interpolation algorithm, lookup-table algorithm. lookup-table method requests to produce a function value saving machine according to the accuracy, constitute sine value table; The cordic algorithm is the application calculation that isput forward in 1959by J.Volder triangle function etc.methodto carry out amethodthrough theDie generation string line that sati