Abstract: The problem of losing throttle control when controlling an AC motor throughout transmission shifts has been solved for a finite set of discrete waveforms. The solution requires making as many discrete speed waveform tables as there are gear ratios in the transmission. Each table has speed entries appropriate for controlling acceleration and deceleration while in its selected gear ratio. In addition when a new gear ratio is selected a transition to the new table with a changed motor rpm can be done with the throttle unchanged. This provides a smooth control for both manual and automatic transmissions.

Abstract: A control system for an AC electric motor on an electric vehicle deactivates the motor when the control system senses a shift in the mechanically coupled transmission extending between the motor rotor and the wheels. The transmission shift condition may be detected by comparing the current transmission ratio to the immediately preceding measured transmission ratio. If these differ, the motor is electrically deactivated. Two successive measures of the same transmission ratio in a range corresponding to a valid transmission ratio indicate the end of a transmission shift hence permitting the safe resumption of excitation of the motor based on the then current measured rotor speed.

Abstract: A two probe time-of-flight system has a transmit probe emitting a diverging beam into a test material at a certain beam-center angle, and a receive probe with its main beam extending into the test material at that same angle, with the two probes being arranged symmetrical about a centerline normal to the test face. The transmit probe generates a pulse wherein a portion of the pulse reflects at the incident angle back to the receive probe, which detects the reflections and marks the reception time as a reference. A sampling unit captures subsequent echo energy returning from a region within the test material. The sampled energy above a given threshold is processed to identify the sample times relative to the marked reference time. The identified sample times are used to determine the depth that the echo energy originated from. Consecutive identified samples in the depth direction are used to detect the height of a flaw within the test material.

Abstract: According to the present invention, there is provided a harmonically suppressed driver for a three phase full bridge pulse width modulated (PWM) inverter, for driving an AC motor. The driver generates three phase PWM waveforms for operating a motor in a speed range of from approximately 240 to 4000 rpm. Below 1800 rpm, voltage reduction is implemented by phase shifting in order to maintain constant volt-sec operation and prevent armature flux saturation. Additional load dependent flux compensation is achieved by measuring motor speed, calculating the slip and providing compensation at large slips.