【作者】 曹宇；

【导师】 魏丰；

【作者基本信息】 华中科技大学 ， 检测技术与自动化装置， 2004， 硕士

【摘要】 作为一种监测电力系统运行状况并自动切除故障以保证电力系统正常运行的自动化装置,继电保护系统对电力网络安全可靠的运行起着十分重要的作用。随着集成电路技术和微电子技术的发展,在微机继电保护系统中采用专用的数字信号处理芯片比采用普通单片机具有更多的优点。本课题采用数字信号处理器设计开发了一种带录波功能的微机继电保护模板,可以实时采集电网中电压、电流、频率等信号,进行保护算法分析,判别当前电网线路或设备的工作状态,一旦有故障发生,则进行相应保护动作,切除故障并记录故障数据。论文主要论述了微机继电保护模板的软硬件设计以及保护算法的选择与实现。在设计方案的时候,充分考虑了电力系统继电保护的可靠性实时性要求高、数据量大的特点,自主开发本模板的软硬件。具体来说,主要有以下几个方面的特点:(1).在继电保护模板的硬件设计中,为了减少控制电路设计的复杂性,借助EDA软件的帮助,我们采用了复杂可编程逻辑电路和硬件描述语言来设计电路,提高了系统开发的灵活性。(2).在继电保护模板的软件设计中,采用灵活的C语言和汇编语言的混和编程模式,功能上采用模块化设计,提高了开发效率,便于维护。(3).在保护算法的软件设计中,选择差动算法来实现故障的快速波形启动判据;选择DFT算法来实现故障的幅值启动判据;并设计了简单的计数差值运算来实现频率故障的启动判据。(4).在模板的保护单元设计中,在复杂可编程逻辑电路中设计了一种简单可靠的保护校验电路,外加与非门实现的闭锁电路,确保在实际运行中不会产生误动作。经过系统的设计与调试,所设计的微机继电保护模板能正常实现各功能,性能基本达到了预期的要求。更多还原

【Abstract】 As a kind of automated device to monitor operating state of electric power system and switch off accident to guarantee the normal operation of electric power system, relay protection system plays an important role in reliable operation of electric network. With the development of integrated circuit technique and microelectronic technique, it shows great more advantages if using special DSP chip instead of MCU in the field of microcomputer relay protection system.We have developed a model of microcomputer relay protection system using DSP with the function of Recorder which collects voltage, current, frequency and so on of the electric network, analyses protection algorithm, distinguishes the functional mode of the current power line or equipment. It also takes some action to protect electric power circuit, switch off malfunction and note the wrong data. This thesis mainly focuses on the development of protection model and design of software algorithm.After comparison of feasible schemes, we independently design software and hardware and fully consider the large need for data size and the high quality for reliability and real-time. Explicitly speaking, this system has following features:(1).In order to reduce the complexity of design of control circuit, we adopt technology of CPLD and HDL for the hardware design with the help of the EDA software. What we did has increased the flexibility of the system development.(2).We adopt flexible model of admixture program in the general design of software and blocking design in its function, which enhances the efficiency of development and is maintained easily.(3).In the software design of protection algorithm, we select differential algorithm to enable the criterion of waveform trouble rapidly; select DFT algorithm to enable the criterion of magnitude trouble; and design the simple count D-value to enable the criterion of frequency trouble.(4).In the model design of protection unit, we realize easy and reliable circuit of protection and checkout with the help of the CPLD technology, and realize the latching <WP=5>circuit with the NAND gate. All these are to avoid the wrong action during the real operation.After systematic design and debug, the microcomputer model of relay protection can realize each function normally, reached the due acquirement basically.更多还原