Patents Assigned to Baldor Electric Companh
  • Patent number: 5936856
    Abstract: A method and apparatus for compensating for common mode voltages in the output of PWM inverters in induction motor systems is disclosed. In one embodiment, a common mode sensing circuit is coupled to the output of a three-phase inverter to detect common mode voltages in the output. A common mode sensing signal generated by the common mode sensing circuit is applied to a multi-level comparator circuit to generate a plurality of gate driving signals. The gate driving signals are used to control a single-phase multi-level half-bridge inverter circuit to generate a compensation signal that is injected by transformer coupling into the PWM inverter output.
    Type: Grant
    Filed: February 13, 1998
    Date of Patent: August 10, 1999
    Assignee: Baldor Electric Companh
    Inventor: Youqing Xiang