Hydro One

About: Hydro One is a company organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Electric power system & Partial discharge. The organization has 1565 authors who have published 1558 publications receiving 36620 citations.

A fundamental study of inter-area oscillations in power systems

Abstract: A fundamental study of the nature of inter-area oscillations in power systems is presented. The effects of the system structure, generator modeling, excitation type, and system loads are discussed in detail. Both small signal and transient stability analyses are used to determine the characteristics of the system. >

Voltage Stability Evaluation Using Modal Analysis

Abstract: The authors discuss the voltage stability analysis of large power systems by using a modal analysis technique. The method computes, using a steady-state system model, a specified number of the smallest eigenvalues and the associated eigenvectors of a reduced Jacobian matrix. The eigenvalues, each of which is associated with a mode of voltage/reactive power variation, provide a relative measure of proximity to voltage instability. The eigenvectors are used to describe the mode shape and to provide information about the network elements and generators which participate in each mode. A simultaneous iteration method, which is well suited to applications involving large power systems, is used for selective calculation of appropriate eigenvalues. Results obtained using a 3700 bus test system are presented illustrating the applicability of the approach. >

Application of power system stabilizers for enhancement of overall system stability

Abstract: This paper provides a detailed account of analytical work carried out to determine the parameters of power system stabilizers (PSS) for the Darlington nuclear generating station presently under construction in eastern Ontario. The results presented are, however, of general interest and provide a comprehensive analysis of the effects of the different stabilizer parameters on the overall dynamic performance of the power system. They show how stabilizer settings may be selected so as to enhance the steady-state and transient stability of local plant modes as well as inter-area modes in large interconnected systems. In addition, it is shown that the selected parameters result in satisfactory performance during system islanding conditions, when large frequency excursions are experienced. Darlington GS, when completed by 1992, will comprise four 1100 MVA, 0.85 p.f., 1800 RPM turbine generators with "CANDU-PHW" reactors, moderated and cooled by heavy water. The station will be incorporated into the 500 kV network through three double-circuit lines. The units will be equipped with transformer-fed thyristor excitation systems and Delta-P-Omega type PSS [1, 2].

Locating and Isolating DC Faults in Multi-Terminal DC Systems

Abstract: A VSC-MTDC (multi-terminal dc) system consists of voltage-source converters (VSCs) connected to a dc network at their dc terminals. The MTDC is most vulnerable to a dc fault which paralyses all the VSCs until the dc fault is cleared. As dc circuit breakers are expensive, this paper proposes a solution based on extinguishing the dc fault current by opening all the ac-circuit breakers (ac-CBs) which the VSCs are already equipped with on the ac-sides. However, it is necessary to identify which dc line is the faulted line (in case it is a permanent fault) so that it can be isolated by fast dc switches (which are much more economical than the dc circuit breakers), prior to restoring the MTDC system by re-closing all the ac-CBs. This paper presents the handshaking method, which locates and isolates the faulted dc line and restores the MTDC without telecommunication.

A universal model for accurate calculation of electromagnetic transients on overhead lines and underground cables

Abstract: This paper presents a transmission line model for the simulation of electromagnetic transients in power systems. The model can be applied to both overhead lines and cables, even in the presence of a strongly frequency dependent transformation matrix and widely different modal time delays. This has been achieved through a phase domain formulation where the modal characteristics have been utilized in the approximation for the propagation matrix. High computational efficiency is achieved by grouping modes with nearly equal velocities and by columnwise realization of the matrices for propagation and characteristic admittance.