Types of Electric Motors

A motor can be described as a device that converts kinetic energy into electrical energy. The process of electricity conversion in a motor is also known as induction. The electric current induced in a motor’s rotor results in torque (power) produced. This torque is proportional to the speed of rotation of the rotor and the magnetic field within the stator. A NEMA design B motor’s differential speed is typically between 1% and 2% under full load.

To choose the best type of motor for your application, make sure to consider its starting voltage. The voltage of the motor must be higher than 10% of its rated output if it is controlled with direct-on-line starting control. If this voltage is lower, the motor will not produce the necessary torque. For this reason, it is important to understand how the different types of starting voltages and currents differ from one another. Once you have determined which type of motor is right for your application, you can start shopping.

There are two main types of electric motors: the DC and the synchronous. DC motors require reversing magnetic alignment in order to operate. The commutator connects two supply contacts to the rotor. This reversal of the polarity is necessary for the rotor to rotate. These are usually used for low-power applications and are commonly found in small tools, elevators, and electric vehicles. There are some differences between the two types, but the main difference is the type of motor.

In terms of efficiency, a DC motor can be highly efficient. If it is connected to a power network, it can be a challenge. A VFD can resolve this problem by controlling the voltages and currents that are supplied to it. These VFDs are usually composed of three sections. The first section of each is the rectifier, followed by a filter with energy storage and an inverter. They work by adjusting the voltage and currents supplied to the motor.

Another type of electric motor is the reluctance motor. This type of motor uses a distributed DC winding and operates without synchronous speed. A reluctance motor has an armature, a stator, and a commutator brush assembly. A reluctance motor’s function is to repel similar poles in an iron device. A reluctance motor’s commutator brush assembly generates an inner magnetic field.

An inverter uses pulse width modulation (PWM) technology to regulate the voltage and frequency of output signals to the motor. In this system, a microprocessor controls the timing and operation of the inverter to regulate the voltage and frequency. The width and duration of pulses determine the average voltage supplied to the motor. The frequency of output waves depends on how often positive transitions occur at certain intervals. Fig. 7.23 shows a typical PWM waveform.

A linear motor is similar to a three-phase motor but generates translational motion directly. As the name suggests, this type is analogous to the rotor of a three-phase motor. The stator becomes flat during the travel distance. A magnetic field develops along the flat path. The rotor of the linear motor is pulled by the longitudinally moving magnetic field in the stator. The motor’s function is then translated into motion.