ABSTRACT
Electric motors are electromechanical devices that convert electrical energy into mechanical energy. During this conversion process, some of the electrical energy is lost and dissipated as heat. Relative to alternatives, electric machines are efficient, cost effective and can scale from very large applications to tiny applications; generally, not feasible for other mechanical energy sources. As the largest economy in the world, the United States is a major player in electricity generation, consumption, and use of electric motors in the industrial, commercial, residential, and transportation sectors. Commercial air conditioning systems can be classified into two broad categories: decentralized air conditioning systems and centralized air conditioning systems. Decentralized air conditioning systems are employed in single and relatively smaller spaces. Centralized air conditioning systems use mainly chilled water as the cooling medium. Central refrigeration systems in supermarkets and grocery stores can have compressor racks employing some parallel-connected compressors.
