Capacitor Motor Research Articles

Optimal placement of the run capacitor in single-phase induction motor designs

A summary is presented of some of the investigations published in an Electric Power Research Institute (EPRI) report (EL-4152-CCM, 1987) concerning the optimization of single-phase induction motors with respect to efficiency for given performance constraints and costs. In this study advanced optimization techniques yield relations between efficiency, cost and capacitance value of the run capacitor. The concept of the optimal capacitance of the run capacitor is formulated to provide a basis for understanding the retrofit configuration for single-phase induction motors proposed by C.L. Wanlass (1977). Theoretical, computational and experimental investigations of the Wanlass configuration are presented to show that this retrofit can significantly improve the efficiency of single-phase induction motors.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Analysis of characteristics of single phase induction motor by finite element method

Due to low loss and high efficiency of the electric motor, it is necessary to secure the material characteristics used in it and to know the inner loss distribution of the motor with weaving its material. This paper presents the numerical analysis of magnetic characteristics of capacitor motor by the finite element method (FEM) which takes account the electric field and the terminal voltage. The calculated value shows the good agreement with the measured one.

Characteristics of 2-winding capacitor motors with tapped auxiliary windings

2-winding capacitor motors with tapped auxiliary windings have been widely used in Japan to drive shaft-mounted fans. Principal performance equations are derived by applying the symmetrical components method to an equivalent circuit. The optimum tap position and symmetrical conditions, effects of equivalent circuit parameters on the alternating torque, steady-state torque speed curve, and the efficiency are discussed, based on these equations. The motor is compared with the T- and L-connected tapped winding capacitor motors.

The efficiency improvement of capacitor motor with ferrite magnetic wedges

With the development of condenser materials, single-phase capacitor motors for domestic use have been made smaller, and the utility for it has been raised in these days. For saving electric energy consumed in motors, the authors have carried out experimental discussions on the capacitor motor. In short, with wedging of soft ferrite materials into the motor slots, the characteristics in locked, no-loaded and loaded motor have been investigated. Owing to ferrite magnetic wedges, Carter's coefficient estimated by the finite element method was reduced, and iron loss of the motor decreased. As the result, efficiency of the motor was improved about 6 % or above.

Determination of reliability from ramped voltage breakdown experiments: application to dual dielectric MIM capacitors : M. Shatzkes, M. Av-Ron and K. V. Srikrishan. Proc. IEEE Reliab. Phys. Conf. 138 (1984)

Determination of reliability from ramped voltage breakdown experiments: application to dual dielectric MIM capacitors : M. Shatzkes, M. Av-Ron and K. V. Srikrishan. Proc. IEEE Reliab. Phys. Conf. 138 (1984)

Abnormal starting torque characteristics of a capacitor motor

Abnormal starting torque characteristics of a capacitor motor

ボビンコイル形高効率コンデンサモータの開発

ボビンコイル形高効率コンデンサモータの開発

REVOLVING-FIELD ANALYSIS OF TWO-SPEED SHUNTED CAPACITOR MOTORS WITH NONQUADRATURE WINDINGS

ABSTRACT The main purpose of this paper is to extend the well-known revolving-field theory for the general development of the so-called analysis equations to predict the performance of two-speed shunted capacitor motors with arbitrary arrangements of their primary windings. It has been found that sometimes by arranging the auxiliary winding at an unconventional location, the motor efficiency can be considerably improved especially at low-speed setting. The accuracy of the present mathematical development has been confirmed by actual measurements on such motors with windings both in quadrature and nonquadrature

Cross-Field Analysis of T- and L-Connected Capacitor Motors with Arbitrarily Displaced Windings

Cross-Field Analysis of T- and L-Connected Capacitor Motors with Arbitrarily Displaced Windings

Cross-Field Analysis of T- and L-Connected Capacitor Motors with Arbitrarily Displaced Windings

The chief purpose of this paper is to extend the well-known cross-field theory for the general development of the socalled analysis equations to predict the performance of both T- and L-connected tapped-winding capacitor motors with arbitrary arrangements of their primary windings. It has been found that sometimes by arranging the auxiliary and the speed windings at unconventional locations, the motor efficiency can be considerably improved especially at low-speed setting. The typical variations in the line current, input power, net torque output and overall efficiency are tabulated for direct comparisons.

DESIGN OF AUXILIARY PHASE WINDINGS FOR SINGLE-PHASE CAPACITOR FRACTIONAL-HORSEPOWER INDUCTION MOTORS

Abstract A method is described for the calculation of the auxiliary-winding parameters of single-phase capacitor motors. The design technique is an extension of that successfully applied to resistance-start motors(1) and is aimed toward assisting the practical design engineer to choose an auxiliary winding which uses the minimum amount of copper while simultaneously satisfying all specifications The equations developed do not use the turns ratio as the main design variable but a new design variable, the ratio of total auxiliary-phase resistance to total auxiliary-phase reactance. The method is equally well suited to computer or non-computer evaluation techniques.

Revolving-Field Analysis of T- and L-Connected Capacitor Motors with Arbitrarily Displaced Windings

Performance equations on T- and L-connected tapped-winding capacitor motors with both the extra-main and the auxiliary windings arranged arbitrarily in space from the main winding are presented in this paper, using the revolving-field theory. Also shown is the fact that these general equations can be employed to yield performance on conventional T- and L-connected capacitor motors. By displacing the windings at locations other than conventional, it has been found that the motor effeciency increases considerably for both high and low-speed operations as well as the manufacturing cost goes down. The variations in the net torque developed and the efficiency as a result of changing the locations of the extra- main and/or the auxiliary winding are shown for the purposes of illustration.

Cross-Field Analysis of Capacitor Motor with Windings not in Quadrature, Extensions to 1- and 2- Phase Thereof

Equations to predict the performance of single-phase induction motor with windings not in quadrature are developed based on a concept of representing a winding by two mutually perpendicular windings, using the cross-field theory. Since the capacitor motor is more general than any other motor in the family of single-phase and even two-phase induction motors, emphasis is thereby placed upon its calculations. The adaptability of equations thus developed to other types of notors is also indicated. A systematic procedure to analyze an induction motor is also given by making use of the present equations. In order to show the influence of winding displacement, the results on a permanent -split capacitor motor are also tabulated.

Describing function analysis of voltage‐controlled capacitor motor with thyristors

Describing function analysis of voltage‐controlled capacitor motor with thyristors

Reply: Plugging of capacitor motors

Reply: Plugging of capacitor motors

Plugging of capacitor motors

Plugging of capacitor motors

REVOLVING-FIELD ANALYSIS OF CAPACITOR MOTORS WITH NONQUADRATURE WINDINGS

ABSTRACT Equations to determine the performance of a single-phase induction motor, especially a capacitor motor, with non-quadrature windings are presented, using the revolving-field theory. Since the capacitor motor represents a very special case in the family of single-phase induction motor, emphasis is thereby placed upon its performance calculations. A procedure arranged in very systematic steps to help analyze an induction motor is also included. In order to demonstrate the influence of winding displacement, the results on a typical permanent-split capacitor motor are also tabulated. To verify the accuracy of these equations, the theoretical results when compared with those obtained from the cross-field development for such motors showed an exact agreement.

Plugging of capacitor motors

This paper analyses the braking characteristics of single-phase capacitor motors by plugging, and presents a method of selecting the best value of capacitance for quick braking. The effect of displacement angle and the turns ratio of the main and starting windings on braking performance have been investigated. It is shown that pole-changing windings can also be used for braking with advantage.

TWO-EQUATION ANALYSIS OF A CAPACITOR MOTOR BY CROSS-FIELD THEORY

ABSTRACT It is shown in this paper that a conventional equivalent circuit representation of a capacitor motor on the basis of cross-field theory can be reduced to another such representation by a suitable transformation. The new equivalent network helps calculate such unknowns as the currents in different parts of the motor and its performance characterstics with comparatively little expenditure of time and effort since it deals with only two simultaneous equations instead of four otherwise needed for a conventional network. The rotor currents, that is the currents in the main and the cross-field axes of the rotor, are determined at first and are then substituted in simple expressions to obtain the main- and the auxiliary-winding currents. An example is also given to illustrate the procedure to calculate the performance of a capacitor motor, using the two-equation analysis method.

PERFORMANCE EQUATIONS AND CALCULATIONS ON L- AND T- CONNECTED MULTI-SPEED CAPACITOR MOTORS BY CROSS FIELD THEORY

ABSTRACT Performance equations on multi-speed capacitor motors for both L- and T- connections are developed, using the cross-field theory. This, in fact, is a generalization of the previous work on two-speed capacitor motors by the author. The circuit equations are arranged into a matrix form and a new concept of z-parameters to represent the motor constants is introduced. To solve for the circuit currents, a complex computer program is used. The complete speed-torque curves are given for direct comparison. The experimental results, which confirm the validity of the theoretical development are also included.