Exam 23: Ac Inverter Drives

All variable voltage inverters lack ____ protection, and they cannot handle oversized motors.

In an AC inverter drive, the four main areas of possible problems are the same as those in a DC drive.

Inverters are used not only to vary the speed of the squirrel-cage motor, but also to vary its ____, start the motor slowly and smoothly, and increase the motor's efficiency.

An inverter converts the applied DC voltage to a(n) ____ DC voltage.

In a variable voltage inverter, the DC voltage is controlled, and the DC is free to respond to the motor needs.

Flux vector drives operate by monitoring rotor position and changing the rotor's position as compared to its orientation to the ____.

A typical DC link, also called a DC filter or DC bus, is a filter circuit composed of an inductor and a capacitor.

If the signal wires from feedback devices are routed next to high-power cables, ____ can occur.

With respect to electrical power in an industrial environment, frequent outages, voltage spikes and sags, and electrical ____ are normal operating occurrences.

In a current source inverter, a large ____ is used in the DC link section.

The feedback device used in a pulse-width modulated variable voltage inverter is called a _____.

The ____ is a type of inverter drive in which the current is controlled while the voltage is varied to satisfy the motor's needs.

An AC drive has three basic sections: the converter, the DC filter, and the output.

The sensors used to sense motor temperatures consist of a nonadjustable ____ switch that is normally closed and opens when the temperature rises to a certain level.

For proper motor operation, the V/Hz ratio (also called the V/f ratio) must be kept equal to one.