Patent ID: 10164555

Abstract:
A half-bridge inverter comprised of upper and lower switches can be placed in linear motor track sections to alternately connect a common point of all drive coils to a full-bus DC power rail (“full-bus”) and a DC reference, according to PWM command signals, functioning as a “virtual mid-bus” to allow bi-directional flow of a sum of currents of all drive coils in the section. Separate upper and lower drive switches of the half-bridge inverters that are also connected to drive the drive coils can then be controlled, according to separate PWM command signals, to synchronize their PWM cycles and duty cycle commands with respect to the virtual mid-bus at times when a mover is not present, resulting in zero voltage across the drive coils, or command different duty cycles with respect to the virtual mid-bus when a mover is present, resulting in a desired voltage across the drive coils. The desired voltage can produce a current in the drive coils to electromagnetically propel the mover.