In recent years,when designing generator synchronous control system,'synchronous block function'has been canceled in the synchronous closing circuit.The reason is:synchronizer has been designed with microcomputer and design is rigorous.Because to cancel synchronous block function,when a generator synchronizes to power grid,the procedure will become more fast.This paper analysed the necessity of the synchronous block function,and emphasized the synchronous block function can not be canceled.

The operation principle of an improved rotational speed power system stabilizer(PSS)is analyzed with the power system damping analysis method.The concept and function of PSS input state variables are detailed,as is the effect of the operational mode and grid structure on PSS working performance.It is concluded that it is currently inadvisable to replace the generator rotational speed signal with the terminal voltage frequency signal as the PSS input state variable.

The organizational achievements obtained from the commissioning of power transmission and transformation project for the Three Gorges Hydropower Station are summarized in three aspects, i.e., the establishment and perfection of commissioning organization and its content system, the establishment of commissioning contingent and technical system, as well as the establishment and perfection of technical system. The technological achievements from engineering commissioning, including principal results in DC equipment or device debugging test, subsystem commissioning test, substation or converter system station commissioning test and system commissioning test, are analyzed. Above- mentioned commissioning test results have been applied in the operation of Three Gorges Power Transmission and Transformation Project, and technical data accumulated in this commissioning test is valuable for future commissioning test of power transmission and transformation project as well as that of UHV projects.

The synchronous switching of circuit breakers can effectively reduce the transient impacts by switching on/off operation.In this paper at first the authors introduce the controlled switcher with artificial intelligence technology(CAT) manufactured by ABB company in brief and describe its working principle;then the on-site test,which is the first time in China to suppress over-voltage in 500 kV power grid by use of synchronous switching technology and CAT that is installed in Jiangling converter station,is summarized and analyzed.Test results show that CAT can evidently suppress switching overvoltage.Finally,it is pointed out that similar products and technology have wide application prospect in EHV and UHV power networks in China.

对500kV输电线路导线进行了融冰电流-时间特性试验和温升试验,得出了500kV输电线路使用的几种主要规格导线的最小融冰电流、融冰电流-时间特性和温升特性,为500kV输电线路制定融冰方案提供了关键的基础性数据.

介绍了对500kV线路进行直流融冰的3种方案:发电机电源提供直流融冰电流;系统电源带可控整流装置提供直流融冰电流;系统电源带不可控整流装置提供直流融冰电流,同时分析了其优缺点,介绍了进行直流融冰所需要的主要设备.

介绍了Z型导线和耐热铝合金导线等新型导线的特性,对普通钢芯铝绞线和钢芯耐热铝合金导线进行了融冰和温升对比试验,得出了采用耐热铝合金导线可以达到运行条件下防止线路覆冰的目的或覆冰线路融冰的目的、并且可以提高线路的热稳定输送容量的结论.

对500kV输电线路导线进行了融冰电流--时间特性试验温升试验,计算研究了改变线路潮流分布实现防止线路覆冰和融冰的可行性、三相短路融冰的可能性、直流融冰的可能性,研究了采用新型导线融冰的可行性.在此基础上,提出了相应的500kV输电线路融冰方案.

Before the station system commissioning, the low voltage energization test has been done for the HV capacitor banks in AC filters and shunting capacitors. According to the test results the HV capacitor banks which the unbalance current is larger have been adjusted. After the energization of station system commissioning, the unbalance current of all HV capacitor banks is within permitted.

针对小水电群接入大系统发生低频振荡的问题,以及湖北鄂西电网经常发生低频振荡的现象,对鄂西电网的网架结构、传输特点和振荡原理进行了分析和研究.结合鄂西电网的特点研究其抑制低频振荡的原理和方法,提出相应解决措施.通过仿真和动模试验,以及现场运行试验,证明适当采用电力系统稳定器(PSS)是一种最简单,且效果明显的抑制低频振荡的好方法.

The importance and the method of thyristor valve low voltage energization have been described in this paper. Compared with the converter station zero load commissioning test, a discussion has been given for the application of the low voltage energization test.

The paper presents an improving scheme for the unbalance protection of high voltage capacitors. The new protection scheme can save workload during maintenance.

In station system test, the converter transformers of PoleⅠand PoleⅡpassed the closing and opening test. Through the test the insulation, protection and etc. of the converter transformers were checked. The data in the test were recorded.

The malfunction phenomenon of the low voltage capacitor component protection of the 3rd harmonic filter at the AC site of a HVDC station during the first energizing test is analyzed and the operating current is calculated according to the measured components parameters. It indicates that the initial operation settings does not consider the mistuning of the filter, and the capacitance variation due to temperature is not compensated inside the relay. the paper gives some proposals to improve the protection criterion.

阐明了直流输电系统安装逆变运行安全控制装置的重要性,介绍了该装置的控制逻辑、结构、组成以及安全可靠性.

介绍了龙泉换流站交、直流滤波器调谐的方法和最终调谐结果.

阐述了高压直流输电站系统试验的概念、内容和方法,并就龙-政高压直流输电站系统试验的有关技术问题作了详细分析,供有关人员参考.

通过深入、细致的调查与研究,揭示了鄂西电网低频振荡的原因及特点,并根据实际情况提出了行之有效的治理措施,为防止电网低频振荡提供了重要的参考价值.

在我国采用电功率信号作为输入量设计的纯算法电力系统稳定器技术日趋成熟,但纯算法构成组合型电力系统稳定器方面的有关技术未见报道.本文对纯算法组合型的电力系统稳定器进行了分析,并结合实际系统中的应用进行了仿真计算,在湖北清江隔河岩电厂对此类型的电力系统稳定器进行了现场试验,验证了其设计原理的正确性和实用性,为进一步开发,推广应用此类型的电力系统稳定器提供参考.

In power system when operating in dry season and low loadcondition,it is common that the operating voltage will be higher.One effective way of solving this problem is to adjust the phase of generator from lag to lead.In order to assure operating properly in phase lead,the low exciting limit unit in the exciter control system should not only be put into operation as equirement but also be adjusted correctly.The paper introduced setting principle,calculation and testing method for the low exciting limit unit using the static out of step characteristic circle.