Overload prevention system to improve intermittent load capacity of electric drive applications

摘要

An overload prevention system and method for an electric circuit having a plurality of components is disclosed, where each component has a set of pre-computed parameters. For each component, monitored parameters are observed; a limited value is computed using the pre-computed and monitored parameters; and it is determined if the limited value reached a limit. If the limited value reaches the limit; the system limits one of the monitored parameters. Pre-computed parameters can include time constant and rated current; monitored parameters can include current; and limited value can be component temperature. A time constant, rated current and rated temperature can be pre-computed such that the temperature stays at or below the rated temperature when the current is substantially equal to the rated current. Per unit values can also be used such that per unit temperature stays at or below unity when per unit current is substantially equal to unity.