Westinghouse Electric

About: Westinghouse Electric is a company organization based out in Cranberry Township, Pennsylvania, United States. It is known for research contribution in the topics: Brake & Signal. The organization has 27959 authors who have published 38036 publications receiving 523387 citations.

A study of equipment sizes and constraints for a unified power flow controller

Abstract: This paper provides a quantitative measurement of the benefit that a unified power flow controller (UPFC) can provide to increase firm power transfer between two large power systems Included is a complete model for a UPFC control system that contains bus voltage control by the shunt inverter, real power transfer between the shunt and series inverters, and real and reactive power control for the transmission line into which the series inverter is inserted A significant part of the model is representation of dynamic limits that coordinate injected current limits for the shunt inverter, power transfer limits between inverters, voltage injection limits for the series inverter, current limits for the series inverter and line voltage limits for the transmission line This paper contains a simple power system simulation to demonstrate the coordinated dynamic control and illustrate issues that power system planning engineers consider in defining applications for a UPFC

Calculation of Synchronous Machine Constants- Reactances and Time Constants Affecting Transient Characteristics

Abstract: Recent advances in the theory of synchronous machines have introduced a large number of new constants. The method of symmetrical components requires sequence reactances, and an accurate theory of transients requires transient and subtransient reactances and time constants. Most of the published discussion on the constants has been concerned with the application, rather than the calculation of values. In this paper, all of the most significant constants are calculated, except the subtransient time constant. A general method of calculation is discussed in which the reactances are accurately resolved into components. Comparisons of test and calculated values are given. The formulas for salient-pole machines and turbine generators are given in Appendixes A and B. The principle of superposition is applied to resolve accurately the reactances into components which can be readily calculated. The induced currents in the field and additional damping circuits are accounted for simply by applying the constant interlinkage theorem.

Memory retention and switching behavior of metal-ferroelectric-semiconductor transistors

Abstract: The memory retention and switching behavior of a metal-ferroelectric-semiconductor transistor using bismuth titanate have been investigated. The study made on p-channel transistors shows that the device has a fast switching speed and a switching threshold at a field of about 15 to 20 kV/cm. It also has a good memory retentivity. The low current OFF state is more stable than the high current ON state. The current in the ON state was found to decay logarithmically with time at long elapsed times. This is attributed to a slow trapping of holes at the ferroelectric-semiconductor interface states.

Digital processing and calculating ac electric energy metering system

Abstract: A metering system for electric utility power line measurements includes voltage and current signal inputs that are randomly sampled and converted to binary representations. A system sequence controller and calculator provides programmed control for processing digital control and data signals and for producing digital calculations of electric energy parameters from the binary representations of the instantaneous signal values. Memory registers totalize and accumulate digitally calculated values for producing visual displays and output signals that correspond to electric energy parameters to be measured.