The Analysis of Harmonic Based on Multi-Processor

随着多核技术的发展,多核计算机逐渐成为市场的主流,由此对程序设计带来了巨大的改变。如何以最少的代价将现有的代码修改成适应多核计算机的程序,已经成为一个重要的课题。从电能质量分析中最重要的谐波检测入手,对谐波检测中利用的傅里叶变换算法进行分析,证明了傅里叶变换结果和谐波的关系,介绍了几种谐波分析的算法,给出了利用OPEnMP编程技术对基于复序列的傅里叶变换算法进行并行化改造的过程,并对并行化的效率进行了分析。实验表明OPEnMP对少量数据的运算效果不是十分理想,比较适合于大数据量的并行运算,同时并行的粒度越大,效果越好。With multi-core technology development,multi-core computer has gradually become the mainstream in the market;It brings tremendous change in program design.How to modify the existing code with the least price and let it adapt to multi-core computers,has become an important issue.Based on the crucial part-harmonic detection in analyzes of the quality of electric energy,analyzes Fourier transform algorithm which used in the harmonic detection,subsequently,proofs of the relationship between the result of Fourier transform and harmonic wave.Furthermore introduces some classical Harmonic analysis algorithms.At the end of this academic thesis emphatically points out the course of parallel transformation in the Fourier transform algorithm which based on complex sequence,and analyses the parallelization efficiency.The experiments show that OpenMP is not expectative for calculating effect of the small amount of data but suitable for the parallel computing of large data

Research of PID Controller Based on BP Algorithm

文中主要研究了基于bP算法的PId控制器在非线性系统中的控制效果以及对权值整定初始化的优化。在介绍bP网络基本原理的基础上以非线性控制系统SIMulInk仿真为例,使用基于bP算法的PId控制器对该系统进行优化和整定,并结合nguyEn-WIdrOW初始化算法为层产生初始权重和偏置值,使得每层神经元的活动区域能大致平坦地分布在输入空间,实现了对PId参数的实时调节,并且使神经网络的学习和收敛速度加快,大大改善系统的初始运行的稳定性。仿真结果表明,基于bP算法的PId控制器在非线性控制系统中对其参数优化整定具有良好的效果。Studies the effects of the BP algorithm based on PID controller in the nonlinear system as well as setting the right values to initialize the optimization.In this paper take example for Simulink simulation of a non-linear control systems,use PID controller based on BP algorithm to optimize the system and setting,which combined with Nguyen-Widrow initialization algorithm,realize the real-time adjustment of the PID parameters,and accelerate the neural network learning convergence.Simulation results show that PID controller based on BP algorithm in the nonlinear control system for its tuning parameter has a good effect

Design and Implementation of Power Quality Detecting System

论文从国家规定的电能质量指标定义入手，介绍了各项指标的计算方法，其中重点讨论了电能质量监测中的谐波计算问题，对基于复序列的快速傅里叶变换算法进行详细的分析和推导，用数学手段揭示了计算结果表示的物理含义。接着探讨了在共享内存的多核计算机平台上，如何利用OpenMP对基于复序列的FFT算法进行并行化改进。论文还从计算机系统结构入手，阐述如何将程序编写成高速缓存友好和能充分利用处理器性能的代码。文中提供了改进后的算法和原始FFT算法的对比结果数据，数据证明利用OpenMP能对大数据量计算的程序进行方便、高效的多线程改造。改进后的算法对于8路（每路8192个采样点）数据的计算只需3毫秒，满足电能质量实...In this paper we paying attention to power quality and discuss the harmonics calculation algorithm which is the most important problem in our program. We use FFT based on complex sequence to calculate harmonic and prove the calculation results physical meaning with mathematical methods. We propose an OpenMP implementation of a Modified FFT Based on Complex Sequence on shared memory parallel comput...学位：工学硕士院系专业：信息科学与技术学院计算机科学系_计算机系统结构学号：2302007115125