Abstract: The short-term real and reactive power optimization of a large system is a non-linear programming problem and its solution requires a considerable amount of computational effort. In actual practice separate real and reactive power suboptimization techniques may be more suitable than a complete optimization(1). The results obtained by the suboptimal techniques under ideal conditions coincide with those from a real and reactive power optimization. In this paper, complete real and reactive optimization has been solved by suboptimization techniques. The proposed approach decomposes the complete problem into two halves, i. e. the optimum voltage evaluation and the real power optimization with optimally determined voltages. A theoretical treatment of the technique along with a qualitative and analytical discussion is provided. The method is applied to a small system and the results obtained are compared with a real and reactive power optimization.

Abstract: A power supply is provided which is capable of operation from either of two power sources, such as on normal power from the usual alternating-current mains, or emergency power from a standby battery; and which will automatically switch from one source to another as the need arises. The power supply includes a transformer having at least two primary windings, and first and second input circuits respectively connected to the two primary windings and to the two sources. The preferred source will be selected by the power supply so long as its voltage is equal to or greater than the voltage of the secondary source.

Abstract: Data processing and computer systems require continuous monitoring of the primary alternating current power. A power failure must be detected very quickly (within a fraction of a cycle), so that the contents of a volatile memory can be quickly converted into a nonvolatile form. This must occur before power system storage is expended and control is lost. RMS power direction is developed by the product of voltage and current with an integrated circuit multiplier device. When power fails, the circuit indicates a power flow reversal or power equals zero from the detected system current times voltage factor. A retriggerable one-shot in conjunction with a NAND gate is utilized to detect the instantaneous voltage drop to zero and current reversal in order to energize other circuits to protect such volatile data in the event of a power failure.

Abstract: This paper concerns a real-time control scheme of voltage and reactive power in power systems when more than two control computers as well as one central coordinating computer are involved. When a large number of voltage and/or reactive power regulating devices are involved in a power system and the number of nodes or lines in which the voltages or reactive power flows are observed and controlled increases, the necessary computing time and memory requirement increase exponentially if the central computer installed at the central dispatching office should take care of all control functions. In addition, the number of channels of the data transmission network becomes very large because the voltage and reactive power flow at each electric station must be transmitted to the central computer and the optimum operating values of regulating devices should be transmitted back to the regulating stations.

Abstract: A power supply for producing a.c. power at low voltage from conventional a.c. supply mains, without heavy-duty mains transformers. The supply is rectified, and switched at high frequency, transformed to low or other voltage and rectified. Control of the switching means is by comparison of voltage ramps with a threshold voltage and the threshold voltage is controlled in accordance with variables including voltage and current output, to vary the duty cycle of the switching means and hence the output.

Abstract: A power regulation system for use in electric drive vehicles having a direct current power supply of a relatively high voltage and which requires a source of relatively low direct current for auxiliary purposes, such as for charging a 12 volt auxiliary battery which operates an electrical system in the vehicle other than the drive train. The system includes a converter having a full wave transistor bridge oscillator operable to apply high frequency input to the primary of a step-down power transformer. The rectified output of the secondary of the power transformer is connected across the low voltage battery. Charging current control is achieved by a Schmitt trigger voltage sensor connected across the low voltage battery to deactivate or activate the converter at the upper or lower ends of a predetermined low voltage range.

Abstract: Minor deviations in color temperature, which occur because of changes in the power supplied to video amplifiers which supply the video signal to a color picture tube, are corrected by adjusting the supply voltage for the screen grids to effect a change by adjustment of the throughgrip of the screen grids. A control amplifier compares the screen-grid supply voltage, the power supply voltage and a reference voltage to control the screen-grid supply voltage.

Abstract: In a power supply system for a high voltage klystron tube amplifier the additional energy required to maintain the body-cathode voltage relatively constant is provided by a surge pass tube, with a relatively simple boost power supply, cooperating with a single high voltage supply. Regulation of the body-cathode voltage is obtained to the relatively inconsequential detriment of the regulation of the body-collector voltage.

Abstract: The results of continuing investigation in the area of optimal control of electromechanical transients in a power system to improve transient stability are presented. A third-order model of a power system is discussed. The results are compared with those obtained using a second-order representation of previous work [1]-[3].

Abstract: A rational method for using switching circuits to produce precision three-phase sine wave power from dc or ac power sources has been developed. A three-phase sine wave format is considered to be composed of voltage segments consisting of stepped waves and square waves generated by separate circuits and combined on a threephase line to produce voltage waveforms with a total harmonic content of 4% prior to filtering. The stepped portions of the wave, called X and Y functions, are generated by a tapped autotransformer and appropriate switches. Only about 20% of the power is generated in the form of steps. A simple circuit that generates a square wave voltage called the "center" function, handles more than 80% of the inverter power. The inverter has the following characteristics: high input power factor (typically 0.9 to 0.95); low output impedance; can energize nonlinear loads without significant change in total harmonic content; and easy to parallel because of low energy storage in the output filter. The inverter has an efficiency of 88-93% and weighs about 120 lb (breadboard). Power rating is 10 k W with 200% overload capacity and output frequency is 60 or 400 Hz.

Abstract: The eight 304 TL pass tubes in the Varian V‐2100B magnet power supply have been replaced with high voltage power transistors. The inadequate protection against high voltage surges in a previous circuit has been corrected, using a fast acting SCR clamp. In addition, further circuit modifications have reduced ripple and thus extended the useful regulating range of the power supply.

Abstract: The description of a scheme where all the excitation energy of a synchronous machine is derived from its output terminals through a potential transformer and a thyristor-controlled ac-to-dc converter is presented. The circuit is controlled by a strong feedback loop and performs the functions of both the conventional exciter and an automatic voltage regulator. The excitation energy is supplied in the form of dc voltage pulses of constant amplitude and variable width at constant frequency. The scheme is meant for isolated power supply and requires only a 12-V dry cell for triggering a pair of thyristors. Some experimental difficulties are also discussed.

Abstract: Advances in technology have made available Silicon High Voltage Transistors for use in television line scan applications. The basic structure of such-devices is discussed comparing with conventional low voltage power devices showing the dominance of the high voltage devices collector region. It will be skhown how this large collector volume impacts on the common emitter characteristics, reducing gain, and the switching characteristics, due to the large amounts of collector stored charge.