This paper analyzes the influence of AC filter switching on AC system voltage of converter stations,and discusses the technical principles of Controllable Line Commutated Converter(CLCC),and then by comparing and analyzing the practical application of CLCC in Converter Station A of Shanghai,demonstrates that CLCC can successfully withstand commutation failure when the switching of AC filters causes three-phase AC voltage distortion.This provides a reference for the application of CLCC technology in other projects.
In the field of substation automation communication, traditional communication protocols such as IEC101/IEC104 and DNP3 face communication security risks due to the lack of security mechanisms. The IEC/TS 62351 standard provides a specification for implementing communication security based on protocol itself. In order to meet the communication security requirements for DNP3 of substation communication terminals and to study engineering implementation solutions for application layer security, the application layer security for DNP3 of substation communication terminals has been achieved. This article elaborates on the implementation details of DNP3 application layer security, then tests and analyzes the communication traffic and computation time data after implementing application layer security. Based on consistency testing, the feasibility of engineering implementation of DNP3 security authentication is verified.
A centralized GOOSE interlocking device scheme is proposed to solve the problem that interlocking between multi-bays needs relevant bays to cooperate with power failure during maintenance and new bay expansion in distributed interlocking system.In this scheme,two centralized interlocking devices with identical software and hardware are configured to exchange information with the intelligent terminal through the process-layer network.The two centralized devices operate in the master/slave mode to achieve centralized acquisition and independent calculation,among which only the host sends interlock information to the intelligent terminal,the slave does not send GOOSE,and the state of the master/slave supports manual and automatic switching.The centralized GOOSE interlocking device in this scheme can be applied to both digital substations and conventional ones,which can minimize the power outage caused by maintenance and bay expansion,and better support the long-term stable operation of substations.
电力系统继电保护装置系统设计复杂,对运行可靠性要求高,装置内部主控元器件受到单粒子效应(SEE)的影响,对电力系统运行稳定构成了威胁.在电力系统装置设计和开发时,必须进行其对抗单粒子效应能力的测试评估.提出了面向电力保护控制处理器的中子辐照测试装置平台和技术,从试验环境、试验软硬件平台架构、试验流程等3个方面建立整个评估测试体系,提出包括主控上位机监视单元、测试系统管理单元、测试系统受试单元、辅助测试单元等在内的测试系统.通过在14 MeV高能中子源上进行测试系统的单粒子翻转试验,结果表明运用该测试系统可以较好评估不同处理器单粒子效应敏感情况,同时该测试系统为电力系统装置程序优化,降低因单粒子效应造成的异常概率提供了量化评估的手段.
某超超临界锅炉HR3C不锈钢高温再热器管在运行过程中发生泄漏,利用爆口宏观分析、化学成分分析、显微组织观察、力学性能分析等方法对高温再热器失效管样泄漏原因进行了分析.结果表明:管子化学成分、力学性能均符合标准要求,第一爆口管子存在明显机械碰磨进而产生纵向裂纹,高温再热器管子的爆管原因为安装过程未有效控制管子与鳍片的间隙,管子在启停过程中发生机械碰磨,产生应力集中现象,这种应力集中极易导致脆性较大的HR3C母材萌生微裂纹,在长期高温高压以及应力的作用下,使得组织中微裂纹迅速扩展进而导致管子开裂泄漏.针对上述问题,从安装质量、检修、监督运行等方面给出了具体的建议措施.
