ME 360 Midterm: ME 360 Alabama Test2 Fall10
Document Summary
Pwm stands for pulse-width-modulation - a way to control the speed of an electric motor. The synchronous speed of an ac motor depends on input frequency, the number of poles, and the motor voltage. An lvdt uses two coils of wire and ac signals to measure velocity of a ferrous core. The resolution of an a/d converter is a function of the range and the number of bits. Placing a larger resistance across the leads of a dynamometer"s generator increases the load (torque) on the dynamometer"s motor. When used as a tachometer, a dc motor will produce a voltage that is proportional to angular velocity. In labview the two main screens are the front panel and the block diagram. Potentiometers and lvt"s are used to measure linear displacement or position. Commutation is accomplished electronically with a conventional brush-type permanent magnet dc motor. An absolute encoder with n tracks has a position resolution of 360 / 2n.
