US 6,404,154 B2 · Force control system

Abstract

A force control system for an electromagnetic actuator includes an observer that outputs signals representing the instantaneous position and velocity of a movable member, and a position controller that receives the output of the observer and signals representing a desired position and a desired velocity. The position controller compares the output of the observer with the desired position and velocity signals to generate position and velocity error signals. The position controller further generates force command signals required to position the movable member at the desired position with the desired velocity based on the position and velocity error signals. The position component may be eliminated from the force command signals, resulting in controlling only the velocity of the movable member. In accordance with other aspects of the invention, a force control system for an electromagnetic actuator includes a flux observer that low-pass filters the voltage applied to phase coils to estimate the flux of the phase coil and provide a signal representing the estimated flux at the output.

Claims20

Dependent claims

A force control system for an electromagnetic actuator, the actuator having a stationary member with a core, a movable member and at least one phase coil positioned to establish a magnetic flux in the core when the phase coil is energized to exert a force on the movable member, the force control system comprising:

an observer that outputs signals representing the instantaneous position and velocity of the movable member;
a position controller receiving the output of the observer and signals representing a desired position and a desired velocity;
the position controller comparing the output of the observer with the desired position and velocity signals to generate position and velocity error signals;
the position controller generating force command signals required to position the movable member at the desired position with the desired velocity based on the position and velocity error signals;
a flux controller receiving the force command signals and converting the force command into a flux command signal;
and
the flux controller generating a phase energization signal based on the flux command signal.

4 more elements

Dependencies are inferred from the claim text.

Force control system

Life of this patent

Force control system

Life of this patent

Abstract

Claims20