Abstract: Disclosed is an AC motor drive (600) for a three phase, 400 Hz., AC induction motor. The application is a constant speed, constant load application. An AC power source with a wide variation in voltage and frequency is rectified to establish a DC bus. A three phase full wave bridge inverter operates on this source. A cascaded sinusoidal reference signal generator (225) generates three sinusoidal voltages 120° phase shifted from one another. These pure sinusoidal reference help reduce harmonic currents. A high PWM frequency is used to operate the power switches of the bridge to reduce current harmonics. The speed regulator (220) generates an error voltage between a speed command voltage and a feedback of DC voltage that is equivalent to the RMS value of the terminal voltage of the motor for speed regulation. The harmonic content of the DC bus current is extracted to provide short circuit protection.

Abstract: Disclosed is an AC motor drive (600) for a three phase, 400 Hz., AC induction motor. The application is a constant speed , constant load application. An AC power source with a wide variation in voltage and frequency is rectified to establish a DC bus. A three phase full wave bridge inverter operates on this source. A cascaded sinusoidal reference signal generator (225) generates three sinusoidal voltages 120° phase shifted from one another. These pure sinusoidal reference help reduce harmonic currents. A high PWM frequency is used to operate the power switches of the bridge to reduce current harmonics. The speed regulator (220) generates an error voltage between a speed command voltage and a feedback of DC voltage that is equivalent to the RMS value of the terminal voltage of the motor for speed regulation. The harmonic content of the DC bus current is extracted to provide short circuit protection.

Abstract: Disclosed is a three phase Vienna converter for converting three phase AC to DC, with active power factor control. Further the control electronics is galvanically isolated from the neutral of the input three phase supply and also from the center terminal of the two series connected output DC filter capacitors. The control circuit is built completely with analog devices to meet stringent electromagnetic interference standards. The converter is capable of operating over a wide range of voltages and frequencies of the input supply voltage.

Abstract: A control device for a vehicle or mechanism includes a portable displacement controller which permits a non-technical user to achieve effective control of the vehicle or mechanism, by moving the portable displacement controller intuitively with little learning effort. A first sensing device, attached to the displacement controller, detects the user's controlling motion. A second sensing device, attached to the object being controlled, detects motion thereof. An interface device receives signals from the sensing devices, processes those signals to determine relative motion of the controlling motion and the object's motion and outputs a control signal in accordance with the processed signals. The sensing devices each detect motion in six degrees of freedom; the sensing devices each include a three-axis accelerometer, a three-axis gyroscope, and a three-axis magnetometer. In specific embodiments, the accelerometers, gyroscopes, and magnetometers include micro-electromechanical system (MEMS) devices.

Abstract: A control device for a vehicle or mechanism includes a portable displacement controller which permits a non-technical user to achieve effective control of the vehicle or mechanism, by moving the portable displacement controller intuitively with little learning effort. A first sensing device, attached to the displacement controller, detects the user's controlling motion. A second sensing device, attached to the object being controlled, detects motion thereof. An interface device receives signals from the sensing devices, processes those signals to determine relative motion of the controlling motion and the object's motion and outputs a control signal in accordance with the processed signals. The sensing devices each detect motion in six degrees of freedom; the sensing devices each include a three-axis accelerometer, a three-axis gyroscope, and a three-axis magnetometer. In specific embodiments, the accelerometers, gyroscopes, and magnetometers include micro-electromechanical system (MEMS) devices.