Adjustable Speed Drives have a number of advantages and disadvantages compared to other types of variable speed controls?

Advantages1-Energy Savings
2- Improved Process Control
3- Reduced Voltage Starting
4- Lower System Maintenance
5- Bypass Capability
6- Multi-motor Control Disadvantages1-Initial Cost
2- Motor Heating at low Speeds
3- Maintenance
4- Output Harmonics5-Induced Power Line Harmonics