A single-phase induction motor variable speed control with power factor correction function is proposed in this paper. The buck-boost based, dual-output AC-DC converter and the single-phase motor are analysed in detail. Zero-crossing distortion of the source input current to the AC-DC front-end converter is addressed and a solution is proposed. Modelling and simulation of the common place capacitor-start, single-phase motor with unbalanced windings is conducted. Experimental results of the proposed drive are satisfactory in that good correlations between predicted and measured output power and shaft torque are attained, that a high power factor line current results for steady-state operation, and that small harmonic content at low motor speed is obtained.

Economic justification of electric drives is the primary reason for many applications. However, the cumbersome trial-and-error calculations necessary to present this aspect often leads to omission of the topic in electric drives courses. This paper presents a MATLAB-based program that generates plots of input power and shaft torque for variable-frequency operation of three-phase induction motors. Based on these graphs, an example is presented illustrating how a cost amortization study for an adjustable speed drive application can be presented with minimal effort and lecture time

A novel dc-link converter utilizing resonant commutation is presented, Since resonant commutation is accomplished, converter switches are thyristors (SCR's) with lower costs than forced commutated devices, Focus is on the variable-frequency operation of the converter, with potential application in variable-frequency custom power delivery or adjustable-speed motor drives, The converter operates with greater stored energy in the dc link, thus offering current holdup capabilities during a contingency which cannot be attained with a conventional resonant dc-link converter and achieves minimum switching losses without increased conduction losses, Harmonic elimination is achieved by employing sinusoidal pulsewidth modulation (SPWM) control of the converter, Simulation results and experimental validation of the resonant commutation of a low-voltage and low-power laboratory model are discussed. Work in progress and the scope of further work are discussed.

Unlike its rotary counterpart, the linear switched reluctance machine (LSRM) lends itself to double-sided excitation and multiple translator (or ''rotor'') configurations that can yield high-force density designs suitable for controlled linear motion in hostile environments, This paper presents the particular design of a 6:4, double-sided, double-translator LSRM that develops 5.1 lb/in(2) of air gap force shear, The work develops a permeance tube based method to allow simple algebraic magnetic circuit analysis and associated prediction of flux linkages regardless of the level of magnetic saturation of the ferromagnetic structure. Theoretical static thrust predictions are made based on the calculation of change in stored magnetic coenergy per unit distance of translator movement, Laboratory testing of a proof-of-principle LSRM, built up to verify the theoretical predictions, shows that the calculated acid measured average thrust values agree within reasonable error over the range of excitation.

An economical and versatile load simulator is described. The load simulator is capable of modeling arbitrary torque-speed load characteristics and emulating load inertia. Alteration of load characteristics is implemented by change of the EPROM stored program in the 8-bit microprocessor-based controller. Limits on application range are defined and discussed. Verification of the load simulator's ability to model several different torque-speed characteristics is presented.

A helical-motion induction motor (HMIM) that can be used in a tandem arrangement of two units to form a direct-acting, two-degrees-of-freedom actuator capable of producing pure rotary motion, pure linear motion, or helical motion is described. It is shown that under appropriate definition of slip the Steinmetz equivalent circuit of an induction motor can be applied to this two-degrees-of-freedom m...

The paper describes control of a helical-motion induction motor (HMIM) which can be used in a tandem arrangement of two units to form a direct-acting, two degree-of-freedom actuator capable of producing pure rotary motion, pure linear motion, or helical motion. A microprocessor-based controller is designed to drive this closed-loop position control actuator. A proportional control with high gain about command position is implemented to give a desired stiffness coefficient. Using the microprocessor system, an artificial viscous damping is introduced to enhance the dynamic performance.

The concept of designing a high-speed, permanent magnet, brushless DC motor aircraft fuel pump drive using a cycloconverter link is examined. A combination of sinusoidal and DC steady-state analysis is used to produce a simple model of the system. A closed-loop control system with an outer loop based on speed and an inner loop based on current is postulated wherein a proportional-plus-integral controller is placed in the forward path to assure minimum speed error. Gains are then set to assure that the eigenvalues of the linearized control system lie within the left half s-plane over the entire full range.

ABSTRACT This paper presents an air calorimetry method of loss measurement suitable for use in efficiency determination of power conditioned electric motor drives. The procedure is based upon a calorimetric chamber that is calibrated using a precisely known, internally generated set of losses. Once a chamber has been calibrated, accuracy of loss determination depends upon repeatability rather than accuracy of instrumentation. Efficiency determination studies of five power conditioned drives are presented.

The first known numerical simulation is presented of a cycloconverter-link self-synchronous motor drive operated by a discrete-time speed controller. Theoretically predicted and laboratory-measured transient and steady-state performances are compared to assess the accuracy of the model. The correlation between predictions made by the average value of motor phase current base simulation and the lab...

A method of thyristor gating management to allow operation of a cycloconverter-link brushless DC motor drive from a variable-voltage variable-frequency (VV-VF) source is presented. Multiple microprocessors are utilized to assure that no compromise in signal processing priority is necessary as both motor and source frequency vary independently over a wide range. The architecture and logic of the de...

Test procedures for the determination of stator resistance, synchronous reactance(s), subtransient reactance(s), leakage reactance, and commutating inductance (special case of cylindrical rotor) values suitable for use in brushless DC-motor analysis are described. Experimental measurements of a set of parameters for a 0.55 kW permanent magnet synchronous machine are presented. In addition, leakage...

Description is presented for a helical-motion induction motor (HMIM) that can be used in a tandem arrangement of two units to form a direct-acting, two-degree-of-freedom actuator capable of producing pure rotary motion, pure linear motion, or helical motion. With the use of field theory analysis, expressions for developed axial thrust and rotary torque are derived. Experimental data recorded from ...

ABSTRACT A PWM strategy is developed to eliminate harmonics of the quasirectangular phase currents of two-phase feeding, self-synchronous motor that interact with the fundamental component of airgap flux to produce pulsating torques in the frequency range of mechanical response when the motor is driven through a midpoint, three-pulse cycloconverter under synchronous envelope control. After establishing the necessary PWM regime, an example is presented wherein harmonic content of phase currents and developed torque are calculated with and without modulation of phase voltages to verify the effectiveness of torque pulsation reduction and to assess the ohmic loss penalty incurred.

Buildup and test of a permanent magnet, tubular, self-synchronous motor and the associated microprocessor-based power conditioning link are discussed. The motor is controlled for variable frequency axial oscillation demonstrating suitability to function as an energy conversion intermediary between a battery pack and an artificial heart pumping element. Strengths and weaknesses of the test bed system are discussed along with future plans directed toward development of an implantable pump drive for an artificial heart.