A rotary machine, which converts electrical energy into mechanical energy, consists essentially of an electromagnet winding or distributed stator winding for generating a magnetic field and a rotating armature or rotor, through which current passes and is acted upon by a magnetic field To turn, some of these machines can be used as a motor, but also for generators.
(Motors) is to convert electrical energy into mechanical energy equipment, which is the use of power coil in the magnetic field force rotation phenomenon, distributed in various users, the motor according to the use of different power into DC motor and AC motor, the power system Most of the motors are AC motors, which can be synchronous or asynchronous motors (the stator speed of the motor does not keep pace with the rotor rotation speed). The motor is mainly composed of a stator and a rotor. The direction of the energized conductor moving in the magnetic field is related to the current direction and the direction of the magnetic induction line (magnetic field direction). The working principle of the motor is the role of the magnetic field on the current force, so that the motor rotation.
It is a machine that converts electrical energy into mechanical energy. Usually work part of the motor for rotary motion, this motor is called the rotor motor; also for linear motion, known as the linear motor. The motor can provide a wide range of power, from milliwatts to thousands of kilowatts. Motor use and control is very convenient, with self-starting, acceleration, braking, reversing, such as the ability to catch, to meet a variety of operating requirements; motor high efficiency, and no smoke, odor, do not pollute the environment, noise Also smaller. Because of its series of advantages, it is widely used in industrial and agricultural production, transportation, national defense, commercial and household appliances and medical electrical appliances.
A variety of motors is the most widely used AC induction motor (also known as induction motor). It is easy to use, reliable operation, low prices, solid structure, but lower power factor, speed control is more difficult. High-capacity low-speed power machines commonly used synchronous motor (see synchronous motor). Not only synchronous motor high power factor, and its speed and load size has nothing to do, only decided by the grid frequency. Work more stable. Need a wide range of speed control occasions more DC motor. But it has a commutator, complex structure, expensive, difficult to maintain, not suitable for harsh environments. Since the 1970s, with the development of power electronic technology, the speed regulation technology of AC motors has matured and the price of equipment has been decreasing day by day. Motor under the provisions of the working standard (continuous, short-term operating system, intermittent operation of the system) can not afford to cause the motor overheating of the maximum output mechanical power called its rated power, the use of the nameplate should pay attention to the provisions . Motor operation should pay attention to the characteristics of its load and motor characteristics to match, to avoid speeding or stalling. Motor speed control methods, to adapt to different production machinery speed changes. General motor speed when the output power will change with the speed. From the energy consumption point of view, speed control can be roughly divided into two types: ① to maintain the same input power. By changing the energy consumption of the governor, adjust the output power to adjust the motor speed. ② control the motor input power to adjust the motor speed.