Design of Permanent Magnet Type Compact ECB Retarder

According to the recent trend of high speed and heavy load in truck & bus services, supplemental brake systems are highly desired to obtain safety, easy operation, and economical advantages such as longer lining life. To meet such requirements, a compact eddy current brake system (ECB retarder) using powerful permanent Nd-Fe-B magnets has been designed, manufactured, and supplied to market.

This paper reports the basic idea, construction design, and material selection of new ECB retarders. Using the derivation from Maxwell equations, the retardation force was obtained, and the design was made based on the obtained principle.