It is very effective on overvoltage accident analysis of power grid and improvement of insulation coordination for power system by online monitoring power system overvoltage to obtain waveform and characteristic parameters. Most of the existing monitoring systems for overvoltage adopt voltage divider to get signal based on centralized monitoring. But, because of the divider’s self-deficienc...

AbstractThe application of line arresters with Zine Oxide elements to HV transmission lines could avoid the faults, induced by lightning stroking. This paper investigated transmission line arresters with series air gap by a set of simulating calculation and testing, A Monte Carlo statistical method was used to determine the distribution of lightning stroking on the towers in the transmission l...

With the rapid development of power electronic technology, frequency control technology was used widely. It caused insulation system degradation in advance with some practice virtue. Dupont corona-resistant polyimide films have excellent characteristic of corona resistance and were used widely in conversion system. No one know the synthetic method but Dupont company and corona resistance mecha...

The operation reliability of the power transformer,which is the major equipment in power system,directly related to the safety and stability of whole power system. In accordance with the technological difficulties encountered in the process of insulation supervision based on the Dissolved Gases Analysis (DGA),several kinds of model and method are presented to improve the reliability and precis...

With the development of automation technology, examine and repair methods of high voltage devices used in the electric power system are developing. Condition-based maintenance, as an advanced technology, will be widely used in the near future. The data acquired by on-line monitoring system is the basis of condition-based maintenance. To realize condition-based maintenance for Metal-Oxide Arre...

Along with the development of distribution automation system, more requests have raised in the dealing-with the fault. As the terminating equipment in the power system, the reliability and the intelligent level of the circuit breaker affect the stability and automatization of the power system.At first, the paper introduces the principle of the controller\\\’s design, and then puts forwa...

The on-line insulation monitoring technique of power apparatus, which is based on the state repair, is one of the rising essential techniques in modem electric power industry. By sensitively detection of insulations, faults can be found in time to avoid the coming accidents, so that the safety, stability, and economy of the power system can ensured.The power cables have always been the key app...

In this paper, the model is based on Luji substation 35kV power distribution system. Simulations about ferroresonances in malfunctions of Arc earthed, single phase grounding disappear and wire-break in different capacitance current are performed with ATP-EMTP. The prevention measurements include connecting nonlinear resistance to the neutral point of three-phase PT high voltage side, connecti...

Non-Grounded or Petersen-Grounded systems are called neutral un-effectual grounded systems (NUGS), which are widely used in the middle and low voltage distribution networks in China. The fault rate of single-phase-to-ground of NUGS is high, but its fault line selection and location have not been well solved yet. It mostly because the fault current is small and the fault trait is not obvious. ...

Lightning protection research mainly focuses on primary equipment, the protection on secondary weak current equipment is lack of research. 500kV Qujiang substation in Shaoguan Guangdong is the pivotal substation of northern Guangdong grid, with the highest comprehensive automation level. 500kV Qujiang substation lies in area where lightning strike happens frequently, especially during thunder...