摘要 |
An improved current sharing signal coupling/decoupling circuit for power converter systems, including the provision of an individual current sharing signal coupling/decoupling circuit for each module of a number of parallel connected modules, each circuit providing an interface between a module's "current sharing signal" port and a common connection bus. The signal coupling/decoupling circuits also share a common ground noted in the disclosure as "current sharing signal ground". The signal coupling/decoupling circuit includes a comparator, a bi-directional switch and a variable voltage reference. The comparator senses the difference between the voltage on the common connection bus, the "common current sharing signal," less an amount set by the variable voltage reference circuit, and the voltage on the module current sharing signal port, the "module current sharing signal". If the module current sharing signal drops below the common current sharing signal, the comparator activates the bi-directional switch, disconnecting the module current sharing signal port from the common connection bus, allowing the remaining parallel connected modules to continue normal operation, thus providing a system that is tolerant of individual module faults. If n modules are the minimum number required to meet a system's current output specification, then the use of n+1, n+2, . . . n+N modules with corresponding current coupling/decoupling circuits will allow for continued operation of the system in the event of failure of 1, 2, . . . N modules, the system reliability increasing with the number of modules in excess of n.
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