DC – AC Motor Conversion
Thirty years ago, DC motors were the workhorse of industry when variable speed was required. These were found in many applications including mine winders, extrusion applications and the steel industry. However, they needed a maintenance schedule including regular brush changes and carbon removal from the windings. Every so often, a major overhaul was required in a workshop to skim the commutators. The DC motors also had inefficiencies with the brushgear and complicated winding arrangements.
DC – AC Motor Conversion
Nowadays, there are better variable speed options using AC motors and inverter control. Inverters are readily available and can perform as well as their DC brothers in both terms of speed and torque. Many companies have a rolling programme of upgrading their DC motors to AC.
The main advantages of AC motor inverter systems over DC are:
- Reduced maintenance costs
- Reduced production downtimes
- Improved efficiency (typically 15-25%)
- Standard products with short lead times
The choice of AC motors to replace DC has to be a careful choice, however and the following need to be considered:
- The torque speed curve of the AC motor has to suit the load
- AC motors tend to be shorter and fatter so space can be an issue
- Forced ventilation may be needed depending on the operational speed range
- There are a variety of AC motors to choose from:
- IE3 and IE4 induction motors
- High efficiency SynRM motors
- Compact HDP motors
IDS engineers are experienced in specifying motor types, powers and speeds to upgrade DC motors to AC and offer this facility to our customers. For further information or an initial chat contact our experienced engineers on 0115 944 10326 or email [email protected]