Island of efficiency helps designers boost performance

Around 80 percent of maximal torque at 90 percent speed is normally considered an efficient duty point for a motor and drive system. However, a more efficient duty point can be found which could benefit a designer tasked with improving a pump system’s efficiency. If you plot motor ISO efficiency curves for various duty points, you will discover an “island” of improved energy efficiency stretching from about 70 to 120 percent of nominal speed at…