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Proposes a time domain model of a fault locator with special reference to fault arc nonlinearities by applying the MODELS language of the EMTP. Digital fault locator algorithm; Fault locator model description; Influence of fault arc characteristics.

Proposes two methods for fault point location in parallel double-circuit multi-terminal transmission lines by using voltages and currents information from ccvt and current transformers at all terminal. Fault location of multi-terminal transmission lines by the impedance relay method; Fault location by using the current diversion ratio method.

Studies digital fault location for high resistance grounded electric power transmission lines. Importance of fault locators to support prompt recovery from transmission line fault; Effect of multiple load taps on single-phase-to-ground fault location; Fault location methods for parallel two-circuit two-terminal transmission lines.

Wind turbine generators in a windfarm are connected by underground cables. Lightning sometimes strikes a nacelle or a blade. Lightning overvoltages due to a direct lightning strike to the system cause damages in the underground cable. Many parameters should be investigated to establish a rational lightning protection design for wind power generation system. Numerical simulation is a useful method to discuss the influence of the parameters on the lightning overvoltages. This paper uses an Electro-Magnetic Transients Program for the lightning surge analysis. This paper discusses the influence of grounding method of metallic sheath of the cable and grounding resistance on the lightning overvoltages for the direct lightning strike to the generation system. [ABSTRACT FROM AUTHOR]

Comments on an article appearing in the January 2000 issue of 'IEEE Transactions on Power Delivery,' which dealt with the features of power distribution quality events. Methods for extracting power quality events from recorded voltage and current waveforms; Transformer energization events.

Comments on an article appearing in the October 1999 issue of 'IEEE Transactions on Power Delivery,' which dealt with two methods for fault type detection. Simulation for performance verification of a proposed method; Success of pre-processing in simplifying the task of neural networks.

In recent years, distributed generation, as clean natural energy generation and cogeneration system of high thermal efficiency, has increased due to the problems of global warming and exhaustion of fossil fuels. Many of the distributed generations are set up in the vicinity of the customer, with the advantage that this decreases transmission losses. However, output power generated from natural energy, such as wind power, photovoltaics, etc., which is distributed generation, is influenced by meteorological conditions. Therefore, when the distributed generation increases by conventional control techniques, it is expected that the voltage change of each node becomes a problem. Proposed in this paper is the optimal control of distribution voltage with coordination of distributed installations, such as the load ratio control transformer, step voltage regulator (SVR), shunt capacitor, shunt reactor, and static var compensator. In this research, SVR is assumed to be a model with tap changing where the signal is received from a central control unit. Moreover, the communication infrastructure in the supply of a distribution system is assumed to be widespread. The genetic algorithm is used to determine the operation of this control. In order to confirm the validity of the proposed method, simulations are carried out for a distribution network model with distributed generation (photovoltaic generation). [ABSTRACT FROM AUTHOR]

Twenty-nine backflashovers were recorded on a 77-kV double-circuit transmission line with single overhead groundwire. Twenty-six of these occurred on phases where power-frequency voltage bias was positive. EMTP analysis of the line shows that the multistory tower model, recommended by the Japanese Guideline of Insulation Design/Coordination against Lightning, suggests a stronger influence of phase position than was observed. Best simulation results were obtained with a simple tower model of constant surge impedance. [ABSTRACT FROM AUTHOR]