In this paper the analysis and solution of following key technical problems are presented: the drafting of commissioning scheme; the selection of the position in AC power grid where single-phase earth fault occurs while there is only one AC feeder at both sides of converter station and corresponding test method, the principle and disposal of the last circuit breaker trip-out function and the perfection of both software and hardware for it; the perfection of control and protection function of frequency converter for cooling of valves.
介绍了系统调试中几个关键技术问题的分析和解决过程：系统调试方案的编写过程；在换流站两侧均为单回交流进线的情况下交流系统单相瞬时故障点的选择和试验方法；最后断路器跳闸功能的原理、配置原则及软件和硬件的完善；换流站阀冷却变频器控制保护功能的完善。
Fourthly, this paper presented the design alternative based on TMS320LF2407A aimed at the main technology parameter of 3kW single-phase photovoltaic grid-connected inverter. This paper made a detailed analysis of the hardware and software of the main control part based on digital signal processer, and built the simulink simulation model which can be realized by DSP. Acording to the requirement of the main control part, this paper made a detailed analysis of the circuit of signal detection.
4针对3kW的单相光伏并网逆变器的主要技术参数，提出了基于TMS320LF2407A实现的设计方案，然后对主控单元的硬件和软件部分做了详细分析，建立了基于DSP实现的Simulink仿真模型，并根据主控单元需要采集的信号，详细分析了信号检测板电路的设计。
When load leveling control strategy is applied in multifunctional grid-connected converter, the realization in hardware and software will change accordingly. Based on the analysis of control structure feature and main circuit configuration feature in multifunctional grid-connected converter, the harmonics detection and interface circuit between converter and grid are further studied.
由于多功能并网变换器在执行加热器负荷均衡化策略时，具体的软硬件实现上会发生相应的变化，论文首先对多功能并网变换器的控制结构与主电路结构进行了分析，根据这些结构的特点对电流指令信号的获取、电网接口电路的设计进行深入的分析。
Detailed introductions were made to the application in frequency converter for unit series multi-electrical level, power bus, micro-computer control and artificial intelligence, total digitalized optical fiber control and power unit standard modulization, insulated grid bipolar transistor drive circuit intelligentize etc.
介绍了变频器的市场情况以及变频技术的现状，详细介绍了单元串联多电平、功率母线、微机控制和人工智能、全数字化光纤控制以及功率单元标准模块化、绝缘栅双极晶体管IGBT驱动电路智能化等技术在变频器上的应用。
In the power grid, the circuit breaker is the most important control and protection of electrical.
在电网中，断路器是最重要的控制和保护电器。
Finally it is verified that the reactors cannot be used in the control of the 220 kV grid short circuit current.
最大限度地提高220kV分区电网的可供电容量，首先要解决的是220kV电网
According to the development plan of North China Grid and the short circuit current increasing cycle and period of Beijing-Tianjin-Tangshan Grid, rational control scheme of short circuit current and countermeasures are put forward.
根据华北电网的发展规化，针对京津唐电网短路电流增长的周期性和阶段性，提出了合理限制短路电流水平的思路和对策。
Principle of Grid Constant Temperature Control Electric Circuit
栅极恒温控制电路原理
The intelligent low energy electron sensor system principle of work, the specific request to the electronic control circuit of double grid air counter, each part of circuits design in electronic control circuit have been discussed.
讨论了智能型低能电子传感器系统工作原理，双栅极空气计数器对电子控制电路的具体要求，电子控制电路中各部分电路的设计。
According to the principles of grid development planning and technical retrofit planning, the integrated automation system will continue to be widely used for EHV grid controlling, and the objects under remote control will expand from circuit breakers to disconnectors and grounded disconnectors.
按电网发展规划和技术改造规划的原则，超高压电网的控制运行方式将继续广泛采用综合自动化系统，远方遥控的对象也从断路器扩展到闸刀和接地闸刀。
Since the limited grid control technology is applied, the 2 point type, non trap circuit becomes possible.
由于采用了软栅极控制技术，使二点式、无吸收电路成为可能。
Based on the characteristics of Inner Mongolia BaoTou grid, taking the 110 kV substation as the research object, the principle of the remote control anti-misoperation locking is established and the secondary control circuit of remote control anti-misoperation locking is proposed to improve the connection.
本文依据内蒙包头电网的自身特点，以110kV电网变电站为研究对象，建立了遥控防误闭锁原理，提出了二次控制回路远方遥控防误闭锁系统改进接线。
The design of the main circuit and its control system of the three-level voltage source PWM rectifier is conducted, the experimental platform is established and the experiments of switching table DTC based on grid voltage orientation.
本文设计了三电平电压型PWM整流器主电路及其控制系统，搭建了实验平台，对基于电网电压定向的开关表直接功率控制进行了实验研究。
By analysis of the traditional inverter control principles, this paper presents a novel inverter control strategy aim at reactive load fluctuations. It makes full use of the original topology of the inverter circuit to achieve the dual control objectives of both grid connection and reactive power compensation.
通过对逆变电源传统控制原理的分析，本文提出了一种针对无功负荷波动的逆变器并网控制策略，该方案充分利用逆变电源原有的电路拓扑结构，达到并网和无功补偿的双重控制目标。
Control Measures of Short - circuit Capacity in Large-scale Power Grid
大电网短路容量的控制对策
Present situation of short circuit current control in Shanghai power grid and Countermeasures
上海电网短路电流控制的现状与对策
Discussion on Short Circuit Current Control in Shandong Power Grid
山东电网短路电流控制问题探讨
It completed performance testing of current, voltage, and other precision testing, in the control unit and hardware-assisted complete circuit of the power grid failures test.
它完成性能测试中的电流、电压等精度测试，并且在控制单元硬件电路的辅助下完成电网故障测试。
The online variable step can also regulate the voltage convergence rate, and the phase-locked control circuit is designed to synchronously trace frequency and phase of power grid automatically.
在线调节步长改变电压收敛速度，设计锁相控制电路，自动同步跟踪电网频率和相位。
And the work principle, the control method, the design of the main circuit and so on are proposed and the experimental results show that this circuit reduced size can be put to use as a new technology of grid rejecting harmonics using solid synchronous, which has the advantages of low grid impedance influence, simple structure, reduced size and greater reliability.
重点介绍了其工作原理、特点及部分电路设计。实验证明该方案可以作为一种新的电网谐波滤波技术应用于实际，具有受电网阻抗影响小、结构简单、体积小、可靠性高的优点。