Load control system having an overload protection circuit
摘要
<p>A load control circuit having an overload circuit (36) capable of protecting a switching element (26) from overload conditions over a wide range of operating conditions. The overload circuit limits the maximum average power dissipation of at least one switching element (26) in accordance with a comparison of an average voltage across the switching element over a half-cycle and a variable threshold. The variable threshold is determined based on an ON-state resistance of the switching element (26) and the environment in which the switching elements are operating. The variable threshold accounts for the squared term (V<2> or I<2>) in determining power dissipation and allows power to be determined based on average voltage. The system includes a short circuit protection circuit (32). It also includes a controller (22) which receives information from a zero cross detector (16) and turns on the switching element (26) in response thereto. <IMAGE></p>
申请公布号
EP1282231(A2)
申请公布日期
2003.02.05
申请号
EP20020079460
申请日期
2000.06.13
申请人
LUTRON ELECTRONICS CO., INC.
发明人
HAUSMAN, DONALD F., JR.;ZAHARCHUK, WALTER STEVEN;LENIG, ROBERT WILLIAM;DEJONGE, STUART