Systemevaluering og brugerevaluering (System evaluation and user evaluation)

A novel actuator control system is characterized by displacement sensor fault detection. The system includes linear variable phase transducer (LVPT) displacement sensors. A pair of engine electronic controls (EEC) each determines the actuator position by measuring the phase shift of the corresponding LVPT output signal with respect to the fixed phase of the LVPT excitation signal. The voltage amplitude of the LVPT output signal has a unique relationship with to the phase of the excitation signal, and is more sensitive to sensor failure than is phase shift alone. A computer in the control compares the amplitude of the LVPT output signal to upper and lower voltage limits for that displacement. Should the computer determine that the voltage amplitude of the secondary winding output signal is out of range, the system will adjust the actuator drive circuits accordingly.