A Novel Claw Pole Eddy Current Load for Testing a DC Counter Rotating Motor Part I: Construction

Abstract

-Providing variable load for testing a motor in high speed conditions is usually a difficult task. The eddy current brake can be used in application of load testing of motors. This paper deals with construction of a novel claw pole eddy current brake which is employed as a load for a DC counter rotating motor (CRM). These kinds of motors have two inner and outer shafts that rotate in opposite directions simultaneously, which are particularly suitable for under water propulsion systems. The prototype 45KW eddy current brake consists of two parts. One of them is installed on the inner shaft of the 60KW DC CRM and the other one is installed on its outer shaft. The simulation and experimental results with prototype brakes are also analyzed by using MATLAB/Simulink and the operational characteristic of the brake is demonstrated as a function of the motor speed and current of the magnetic poles.

Novel Claw Pole Eddy Current Load for Testing DC Counter Rotating Motor - Part II: Design and Modeling

“…Finally, assuming that the sum of mechanical loss of the motor, mechanical loss of the eddy brake and the eddy current loss of the motor is equal in loading and no-load tests under the same speed conditions, the eddy current loss of the eddy brake is obtained by subtracting the no-load loss of the system from the loading loss of the system [8].…”

“…According to (8), (9), (10) and (11), the eddy current losses in either part of the claw pole, including the triangular part and the rectangular part, are obtained from the following relations:…”

“…The present paper, together with a companion paper (Part I) [8], deals with the construction, design and modeling of the novel claw pole of the eddy current load constructed for testing counter-rotating motors. As shown in Fig.2, the construction of the testing system includes the counter-rotating motor (CRM) [9] …”