DC motor control method

DC motor controller is a special type of electrical equipment that converts electrical energy into mechanical energy. DC motor receives electrical energy by utilizing direct current, and then converts this energy into the automatic rotation of the motor. DC motors are almost ubiquitous, they utilize the magnetic field created by the currents that drive the rotor fixed to the output shaft, and the speed and output torque depend on the motor's design and electrical input.

The follow is the list

• How DC Motor Controllers Work

• There are 3 speed regulation methods for DC motors

How DC Motor Controllers Work

DC motors vary in power and size and can be used in electric hoists and elevators, electric cars, and toys, depending on the mechanism. DC motor consists of two basic parts: the armature and the stator. The stator is the stationary part of the motor and the armature is the rotating part. DC motor uses, in addition to coils, a set of stationary magnets in the stator, with current flowing in the loops of the wires, creating an aligned electromagnetic field. One or more coil windings of insulated wire are wrapped around the core of the motor to concentrate the magnetic field. The windings of the insulated wire are connected to a rotary electrical switch (commutator), which continues to apply current to the coil windings. A rotating electrical switch allows each armature coil to be energized, producing torque or a steady rotational force. After the coils are turned on and off in sequence, a magnetic field is created that interacts with different areas of the stationary magnet, creating torque. These basic working principles allow DC motors to convert electrical energy from direct current to mechanical energy that can be used to propel equipment, all through rotational motion.

There are 3 speed regulation methods for DC motors

1. Change the armature circuit resistance for speed regulation

All kinds of DC motors can be adjusted by changing the resistance of the armature circuit. When the load is constant, with the increase of the external resistance in series, the total resistance of the armature circuit increases, and the motor speed decreases. This speed regulation method is stepped speed regulation, the speed regulation ratio is generally about 2:1, the speed change rate is large, it is difficult to obtain low speed under light load, and the efficiency is low, so it is rarely used now.

2. Change the armature voltage for speed regulation

Continuously changing the armature supply voltage can make the DC motor realize stepless speed regulation in a wide range. As mentioned above, there are two ways to change the armature supply voltage. One is to use the generator-motor set power supply speed control system. The other is a speed control system powered by a thyristor converter.

3. DC motor pulse width speed regulation method using high-power semiconductor devices

The PWM system has a long history, but due to the lack of high-speed and high-power switching devices, it has not been widely used in practical production in time. At present, due to the mature manufacturing process of high-power transistors (GTR), especially IGBT power devices, and the continuous decline in cost, the DC motor pulse width speed regulation system realized by high-power semiconductor devices has developed rapidly. At present, its maximum capacity has exceeded dozens of on the order of megawatts.

Hangzhou New Hengli Electric Machine MFG. Co., Ltd. has been named the provincial advanced enterprise by Zhejiang provincial government and become a state grade-2 enterprise in 1988. Our motor max-power reaches 15000kW (A.C. motor), 2800kW (D.C. motor), and max-center-high dimension of our motor reaches 1250mm.