Induction Versus Permanent-Magnet Motors for Electric Submersible Pump Field and Laboratory Comparisons

Most hydrocarbon production using submersible pumps requires pumping of fluid that is 95% water or higher. Energy used to produce salt water is wasted, and disposal is expensive. Electricity costs are significant, and system efficiency is a major concern. In this application, induction motors (IMs) are less efficient than permanent-magnet motors (PMMs). Laboratory tests measured efficiency, power factor, kilowatts, current, and speed at various loads and frequencies. Field tests measured input power and flow using the same pump for both systems with negligible well drawdown. On average, the PMM used 20% less power than the IM.