THERMAL ANALYSIS OF THE ELECTRODYNAMIC BRAKE

ABSTRACT

Braking using the eddy current induction phenomenon is used in traction systems, retarders supporting the truck braking system, but also in the testing of rotating machines to create artificial loads. In addition to the desired phenomenon of interaction between the magnetic field generated by the electromagnetic brake coils and the field created in the brake disc as a result of induced electromotive forces causing eddy currents, during the brake operation is generated heat that is the effect of the eddy currents through the resistances of the disc material micro-areas. The article presents an analysis of the heating up of the brake disc during operation. An increase in temperature in the zone of the magnetic field of electromagnets was observed. The electrodynamic brake presented in this paper was designed as a load system for electrical machines up to 1 kW and rotational speeds up to 3500 rpm. The brake disc is made of aluminium and the magnetic field is made of electromagnet assemblies powered by direct current. The current of up to 20A flowing through a set of coils makes it possible to obtain a braking torque of 10Nm. The heat emitted during the operation of the brake causes its elements to heat up. The temperatures observed during the operation of the brake reached 50°C on the surface of the disc. Subsequent elements exposed to heating are the electromagnets of the braking system. The thermal analysis of the brake will allow optimization of its structure, enabling its effective operation and efficient removal of heat from areas exposed to heating.

Keywords: Eddy current brake, thermography