Patent ID: 6134129
Filing Date: 2000-10-17
Classification: H02J

Abstract:
An improved circuit for coupling/decoupling the current sharing signal terminal of a power converter module to an interconnecting bus in a power supply system including a plurality of current mode controlled power converter modules normally having their current sharing signal terminals connected to the interconnecting bus, the output terminals of said modules being connected in parallel to energize a common load with a system output voltage, the circuit comprising:variable reference means for developing a variable reference voltage;first comparator means for comparing the voltage developed at the current sharing signal terminal of a corresponding power converter module to said variable reference voltage and operative to generate a first control signal having a first signal state when a first predetermined difference indicative of normal operation of the module is detected between the compared voltages, and having a second signal state when a second predetermined difference indicative of a malfunctioning module is detected between the compared voltages;fixed reference means for developing a fixed reference voltage;second comparator means for comparing a signal derived from the system output voltage to said fixed reference voltage and operative to generate a second control signal having a first signal state when a third predetermined difference indicative of normal operation of the system is detected between the voltage compared by said second comparator means, and having a second signal state when a fourth predetermined difference indicative of a malfunctioning system is detected between the compared voltages; andswitching means responsive to said first and second control signals and operative to connect said current sharing signal terminal to said interconnecting bus when both said first and second control signals are of said first signal state, and to disconnect said current sharing signal terminal from said interconnecting bus when either of said first and second control signals are of said second signal state, whereby in the event said corresponding power converter module malfunctions, it will be effectively disconnected from the system.