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A negative input-resistance compensator is designed to stabilize a power electronic brushless dc motor drive with constant power-load characteristics. The strategy is to feed a portion of the changes in the dc-link voltage into the current control loop to modify the system input impedance in the midfrequency range and thereby to damp the input filter. The design process of the compensator and the selection of parameters are described. The impact of the compensator is examined on the motor-controller performance, and finally, the effectiveness of the controller is verified by simulation and experimental testing. Index Terms--Brushless dc motor drive, negative input-impedance instability.

Fundamental frequency analysis is used to examine the LCC series-parallel loaded resonant converter with a capacitive output filter when operating as a high-power-factor rectifier. Optimum values are identified for the Q factor and voltage conversion ratio such that zero-voltage switching is just maintained, while minimizing the resonant circuit conduction losses. A simple resonant current control loop is shown to provide an effective mechanism of active control, achieving a high-quality input current waveform over a wide load range. Results are presented from a 1-MHz 160-W prototype. Index Terms - AC/DC converter, high-power-factor rectifier, resonant converter.

In this paper, the averaged small-signal model of the dual-interleaved buck converter is extended to include the phase interaction effects that arise from the interleaved sampling of the phase currents. Sampler decomposition techniques are used to extend the averaged model, revealing a slow-scale instability that can place significant restrictions on the choice of controller parameters. The model is confirmed by simulations and measurements using a 60-kW dual-interleaved prototype with an interphase transformer; however, the analysis is equally applicable to interleaved converters without magnetic coupling. [ABSTRACT FROM AUTHOR]

An adaptive energy management control with an integrated variable rate-limit function is described for an energy storage system (ESS). The proposed control protects the primary power source(s) in the system as effectively as possible from sudden load transients within the constraints of the available stored energy. The control can be designed to use the available energy more aggressively during load changes in the low- or high-power regions while offering the lowest possible rate-of-change of the main source power or offers a fixed minimum rate-of-change in power for a given total load and amount of energy. The control design is described in detail and demonstrated experimentally when applied to a supercapacitor ESS within an aircraft test facility. [ABSTRACT FROM PUBLISHER]

A system-level modeling technique for a switched reluctance generator (SRG) is described for aerospace applications. Unlike existing techniques, this model is very simple and only reproduces the average behavior of the input–output variables that are required for system-level analysis of the aircraft power distribution system. The model is parameterized from the measured generator response, avoiding the need for a detailed knowledge of the equipment structure, which may be unavailable. The modeling procedure is described in detail and validated by measurements on an SRG within an aircraft test facility. [ABSTRACT FROM AUTHOR]

A negative input-resistance compensator is designed to stabilize a power electronic brushless dc motor drive with constant power-load characteristics. The strategy is to feed a portion of the changes in the dc-link voltage into the current control loop to modify the system input impedance in the midfrequency range and thereby to damp the input filter. The design process of the compensator and the selection of parameters are described. The impact of the compensator is examined on the motor-controller performance, and finally, the effectiveness of the controller is verified by simulation and experimental testing. [ABSTRACT FROM AUTHOR]