What is meant by PMDC?

PMDC stands for Permanent Magnet DC Motor

A Permanent Magnet DC Motor is similar to an ordinary dc shunt motor except that its field is provided by permanent magnets instead of salient-pole wound field structure.

There are three types of permanent magnets used for such motors namely;

(i) Alnico Magnets
(ii) Ceramic magnets
(iii) Rare-earth magnets

The major advantages are low noise, small size, high-efficiency, low manufacturing cost.