基于OFDM的电力线通信系统关键技术研究与实现

发布时间：2019-03-21 11:16

【摘要】：电力线通信的概念由来已久,随着智能电网概念的不断发展和演进,电力线通信技术迎来了新的机遇和挑战。传统的窄带电力线通信技术提供非常有限的数据传输能力,已经无法满足现代智能电网的发展需求,采用具有更高传输能力的新一代通信技术迫在眉睫。为了对抗电力传输线上的强噪声、强干扰和严重的频率选择性衰落,以欧洲的PRIME和G3-PLC为典型代表的新一代窄带电力线通信系统倾向于采用具有强灵活性和抗多径衰落能力的正交频分复用(OFDM)技术。目前,以欧盟的G3-PLC标准为重要参考的我国新一代窄带电力线通信国家标准正在拟定过程中,充分掌握G3-PLC通信的核心技术,非常有助于满足未来新一代窄带电力线通信国标设备的快速实现和部署。本文主要研究了基于OFDM技术的G3-PLC电力线通信系统的设计与实现。在分析G3-PLC标准的基础上,完成了通信系统仿真模型的搭建,并在自行设计的DSP硬件平台上完成了系统的实现。首先,简要回顾了电力线通信发展的历史和国内外的发展现状,对比了目前影响广泛的主流电力线通信标准,给出了相近标准在重要技术指标上的异同。其次,介绍了基于OFDM的G3-PLC标准。着重描述了G3-PLC标准的物理层规范和基于OFDM的电力线通信系统的整体结构,研究了系统的各种关键技术。第三,基于G3-PLC标准的物理层规范,在Simulink平台搭建了整个系统的仿真模型,采用面向硬件实现的模块化电路搭建方式,详细给出了每个模块的结构和参数设置情况,并对系统进行了仿真,以验证所设计算法的正确性和有效性,为下一步的硬件实现提供了理论支撑。最后,基于自行设计的DSP硬件平台实现了基于OFDM的电力线通信系统。给出了所采用的硬件平台和芯片,描述了系统顶层设计和涉及的中断服务程序。在DSP芯片内部开辟了专属的数据存储区,有效实现了与MCU的指令和数据传输,以及对前端芯片的参数设置和状态监控。由于DSP芯片的内存有限,根据使用情况给出了合理的内存分配方式,优化了数据的存储和读取。基于DSP的单线程工作特性,给出了所设计的发送端和接收端信号/数据的处理流程,详细说明了系统中每个模块的功能和特点,着重讲述了同步模块中针对G3-PLC前导符波形相关特性提出的相关峰波形检测的算法及其实现。最后,给出了典型的实测场景和测试性能指标,验证了所设计系统的有效性和可靠性。
[Abstract]:The concept of power line communication has a long history. With the continuous development and evolution of the concept of smart grid, power line communication technology ushered in new opportunities and challenges. The traditional narrow-band power line communication technology provides very limited data transmission capacity, and it is no longer able to meet the development needs of the modern smart grid. It is urgent to adopt a new generation of communication technology with higher transmission capacity. In order to combat strong noise, strong interference and severe frequency selective fading on power transmission lines, The new generation narrowband power line communication systems represented by PRIME and G3-PLC in Europe tend to adopt orthogonal Frequency Division Multiplexing (OFDM) technology with strong flexibility and anti-multipath fading ability. At present, China's new national standard for narrowband power line communication, which is based on the G3-PLC standard of the European Union, is in the process of being drawn up, and the core technology of G3-PLC communication is fully mastered. It is very helpful to meet the rapid implementation and deployment of the new generation narrowband power line communication national standard equipment in the future. This paper mainly studies the design and implementation of G3-PLC power line communication system based on OFDM technology. Based on the analysis of the G3-PLC standard, the simulation model of the communication system is built, and the realization of the system is completed on the DSP hardware platform designed by ourselves. Firstly, this paper briefly reviews the history of the development of power line communication and the current development situation at home and abroad, compares the mainstream power line communication standards which have a wide influence at present, and gives the similarities and differences of the similar standards in the important technical indicators. Secondly, the G3-PLC standard based on OFDM is introduced. The physical layer specification of G3-PLC standard and the whole structure of power line communication system based on OFDM are described emphatically. The key technologies of the system are studied. Thirdly, based on the physical layer specification of G3-PLC standard, the simulation model of the whole system is built on the Simulink platform. The hardware-oriented modular circuit is used to build the model, and the structure and parameter settings of each module are given in detail. Simulation of the system is carried out to verify the correctness and effectiveness of the designed algorithm, which provides theoretical support for the next step of hardware implementation. Finally, based on the self-designed DSP hardware platform, the power line communication system based on OFDM is implemented. The hardware platform and chip are given, and the top-level design and interrupt service program of the system are described. The special data storage area is opened in the DSP chip, the instruction and data transmission with MCU is realized effectively, and the parameter setting and status monitoring of the front-end chip are also realized. Because the memory of DSP chip is limited, the reasonable memory allocation mode is given according to the usage situation, and the storage and reading of data are optimized. Based on the single thread characteristic of DSP, the processing flow of signal / data at the sending and receiving end is given, and the functions and characteristics of each module in the system are described in detail. This paper focuses on the algorithm and implementation of correlation peak waveform detection for G3-PLC preamble waveform correlation characteristics in synchronization module. Finally, the typical measured scene and test performance index are given, and the validity and reliability of the designed system are verified.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN913.6

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