SYS-1. Rated speed vs weight, size & cost

For the system driving a pump and consisting of a motor and a frequency converter investigate how chosen rated speed of the machine affects it’s weight, size and cost.

Design the system with the following parameters:

• Pump: rated flow 100 l/s, head 110 m, pump efficiency 86%, speed 1100 rpm,
• Motor type SCIM, cooling IC411,
• Grid voltage 400 V.

First choose machine with the synchronous speed of 1000 rpm. Record weight and cost of motor and of frequency converter.

As the alternative variant choose machine with synchronous speed of 1500 rpm. Record weight and cost of motor and of frequency converter.

Compare weights and costs of the two motors (1000 and 1500 rpm), then compare costs of the two systems. Draw conclusions and explain. Can you explain the results/conclusions as electric machine designer?

• [!] Make sure you keep machine type, efficiency class, cooling, protection class and other «influential» parameters constant (the same). Include these parameters in your report.