When choosing a electric motor for an application, a primary consideration is the speed range it will be operated in. When a motor is run substantially slower than its ranked base speed, a number of potential adverse effects will come into play, including reduced cooling performance, reduced power efficiency and a change in the motor’s velocity and torque characteristics. To mitigate this issue, some motors and speed controllers have already been designed especially to drive a load at low speeds with precise control.
Most domestic and commercial motor applications use 3-phase asynchronous induction motors, which operate at a speed that is determined by the frequency of the supply power. When an application operates at a continuous speed, the only thing that is required may be a gearbox or swiftness reducer that brings the motor speed down to the mandatory level. Nevertheless, many applications require the quickness of the motor to be various during operation.
This is usually achieved utilizing a VFD or Variable Frequency Drive, which controls the speed by modifying the frequency fed to the motor. Choosing the right motor and VFD type depends upon a variety of factors, however, it’s important to first look at the way the characteristics of a electric motor change when the swiftness is reduced.
A motor usually has a base speed, specified by the manufacturer, that it is certainly made to operate at. However, if a motor is operated below the bottom speed, it could experience reduced efficiency of the coolant system. Especially with commonly used vitès redukteur bwat ... Totally Enclosed Enthusiast Cooled (TEFC) and ODP (Open Drip Evidence) motors, where the cooling program consists mainly of a shaft-mounted lover, a decrease in speed results in reduced airflow over the engine and lack of cooling, and heat buildup occurs. Especially when the engine is operated with complete torque at low speeds, heat can easily build up within the motor to harming levels.