Motors and generators are closely related. These devices are essential to all types of functions. To complicate things further, they are sometimes combined into a machine known as a motor-generator.
OEMs purchase AC custom motor generators for vital equipment, from precision military motor generators for defense applications to drag cup motor generators for industrial monitoring systems. But for the average consumer, motors, generators, and motor generators can be easy to confuse. The following information can help demystify these devices.
Motors Vs. Generators
The main difference between a motor and a generator is the flow of current. If the flow of current is going into the device to generate torque or physical power, it is a motor. Motors are typically used to initiate or control motion, such as powering a fan, spinning an axle, or opening an automatic door. Conversely, if physical power or torque is being introduced into a device that creates an electric magnetic frequency, which is then converted into electricity, it is a generator. Generators are used to harness energy, which creates electricity, from motion. A simple example of this is the small generator located in a wind-up flashlight.
Motors and generators use a lot of the same components, including a stator, which is the stationary part of the device, and a rotor, which spins when the device is in operation. These two parts work through the configuration of a magnet and a coil of conductive wire or other material that connects to a commutator or slip ring.
What’s The Difference Between AC Generators And DC Generators?
The difference between AC generators and DC generators is mainly based on the presence of a slip ring or commutator. In an AC generator, a slip ring is used, which serves to generate opposite polarities of electromagnetic force, also known as voltage. The voltage that’s internally generated within all types of generators is always AC. The addition of a commutator will reverse the current to generate DC power.
DC generators are rarely used today. Originally called “dynamos”, they were used for various applications in the earliest days of electrical industrial machinery and power generation, but their many limitations compared to AC generators and alternators have led to their wide phase-out. They are not completely obsolete, however, and are still sometimes used for low voltage applications where alternators would be inefficient and in smaller generator applications that are mainly powered by hand, such as crank-powered radios and recharging equipment.
What’s The Difference Between AC Motors And DC Motors?
The structural differences between AC motors and DC motors are very different, and within these two different types, there are many subsequent types of motors. The main difference between AC and DC motors is the type of current that’s used to produce torque. DC motors use a commutator or a controller to convert alternating current into direct current, which generates the electromagnetic field between the stator and rotor to produce motion. AC motors will run without this change in current and instead use a variety of other components, which determine how the AC motor operates.
What About Motor-Generators?
Motor-generators, sometimes specified as AC motor generators or M-G sets, are similar to standard motors but instead of simply converting electrical power into torque or motion, they can convert that energy into other forms. They are used to change frequency, voltage, or power phases. They are also used as isolators that keep electrical loads separate from a power supply line. Although motor-generators may be constructed as a single equipment unit, they are comprised of a generator that is powered by a separate but integrated electric motor.
Unlike motors and generators, which are used in many household and hobby applications in addition to more complex systems, motor-generators are mostly used for industrial and specialty applications. They are applied where phase-matching, electrical load isolation, or operational consistency is needed in large power supply systems.