基于FPGA的SVPWM系统的研究与实现

发布时间：2018-11-03 16:33

【摘要】：随着电力电子技术的快速发展,交流变频调速技术也取得了显著的进步。空间矢量脉宽调制(SVPWM)技术通过控制电压空间矢量来形成近似圆形的磁链矢量,具有谐波含量少、转矩脉动小、民压利用率高等优点,是一种性能优越的调速技术。现场可编程门阵列(FPGA)具有功耗低、速度快、灵活性强、开发周期短等优势。因此利用FPGA实现SVPWM可以有效提高系统的运算速度和适用性。首先介绍了 SVPWM控制的原理及设计方法,根据零矢量插入位置的不同,阐述了七段式和五段式两种脉宽调制方式的优缺点,七段式调制方式谐波含量小,开关次数多,五段式调制方式开关次数少,谐波含量高。为了使谐波含量尽量少,选择了七段式脉宽调制方式。其次分析了单模式过调制算法,其算法简单、易于实现,但是损失了一部分基波电压,并且无法达到六拍阶梯波状态。为了改善单模式过调制算法的不足,采用了双模式过调制算法,这种过调制算法对输出电压的基波进行了补偿,系统能够平滑地从线性调制区过渡到六拍阶梯波状态。然后采用自顶向下的方法设计了系统的各个模块,完成SVPWM控制系统顶层文件的设计,并用Modelsim分别对各个模块和整个控制系统进行了仿真,仿真结果和理论分析一致。最后,在开发板上实际验证了基于FPGA的SVPWM控制系统,实验结果与仿真结果相同。结果表明双模式过调制算法改善了单模式算法的缺陷,能够输出六路性能良好的PWM控制信号,达到了预期的设计目标,验证了设计的正确性与可行性。
[Abstract]:With the rapid development of power electronics technology, AC frequency conversion speed regulation technology has made remarkable progress. Space Vector Pulse width Modulation (SVPWM) technology is an excellent speed regulation technique, which forms an approximate circular flux vector by controlling the voltage space vector. It has the advantages of less harmonic content, less torque ripple and high utilization ratio of the civilian voltage. Field Programmable Gate Array (FPGA) has the advantages of low power consumption, high speed, high flexibility and short development cycle. Therefore, using FPGA to realize SVPWM can effectively improve the speed and applicability of the system. Firstly, the principle and design method of SVPWM control are introduced. According to the different position of zero vector insertion, the advantages and disadvantages of seven segment modulation and five segment pulse width modulation are discussed. The switching frequency of five-segment modulation mode is less and the harmonic content is high. In order to make the harmonic content as small as possible, seven-segment pulse width modulation mode is chosen. Secondly, the single-mode over-modulation algorithm is analyzed. The algorithm is simple and easy to implement, but it loses part of the fundamental voltage and can not reach the six-beat step wave state. In order to improve the shortcomings of the single mode overmodulation algorithm, a double mode overmodulation algorithm is adopted, which compensates the fundamental wave of the output voltage, and the system can smoothly transition from the linear modulation region to the six-beat stepped wave state. Then every module of the system is designed by using the top-down method, and the top-level file of the SVPWM control system is designed. The simulation of each module and the whole control system is carried out by Modelsim, and the simulation results are consistent with the theoretical analysis. Finally, the SVPWM control system based on FPGA is verified on the development board, and the experimental results are the same as the simulation results. The results show that the dual-mode over-modulation algorithm can improve the defects of the single-mode algorithm, and can output six PWM control signals with good performance. The desired design goal is achieved, and the correctness and feasibility of the design are verified.
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN761;TN791

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