How do various types of motors automatically regulate power and circuits?

Servo motors work by monitoring and adjusting the motor's operating status through an internal feedback system, enabling the motor to operate at a predetermined position and speed. In a servo motor, an encoder is usually used as a feedback sensor to control and adjust the motor by detecting the position and speed signals of the motor rotor.

The main structure of a servo motor includes: motor body, encoder, and controller. The motor body is the component responsible for generating power, which can be used as DC motor, AC motor, stepping motor, etc. The encoder is a sensor used to detect the position, speed, angle and other information of the motor rotor, and there are two common types of encoders: absolute encoder and incremental encoder. The controller is used to receive the feedback signal from the encoder, and then calculate the control algorithm and output the control signal to control and adjust the motor.

There are many kinds of control algorithms for servo motors, among which the more common ones are PID control algorithm, fuzzy control algorithm, adaptive control algorithm, etc. PID control algorithm refers to the proportional-integral-derivative control algorithm, and its basic idea is to obtain the control signal through proportional, integral, and differential processing of the error. Fuzzy control algorithm is a kind of nonlinear control algorithm, which adopts fuzzy mathematics to describe the system, and arrives at the processing result through reasoning and judgement. Adaptive control algorithm is an autonomous learning control algorithm, which can continuously self-adjust and optimise over time to improve the control accuracy of the motor.

Servo motors can achieve a variety of control modes in the process of application, including position control mode, speed control mode, torque control mode and so on. Position control mode is to control the motor to reach the target position by controlling the motor output angle (or position) signal. Speed control mode is to control the motor to reach the target speed by controlling the speed signal output from the motor. Torque control mode means to control the motor to reach the target torque by controlling the torque signal output from the motor.

In the application of servo motors, the closed-loop control mode is usually used for control. Closed-loop control refers to the control of the system through the use of feedback signals to improve control accuracy. Relative to closed-loop control is open-loop control, open-loop control is only based on input signals to control the output, there is no feedback link, and it is easy to be affected by external interference and lead to large control errors.

In summary, the working principle of the servo motor is to monitor and adjust the operating state of the motor through the internal feedback system, so as to achieve accurate control. Servo motors are widely used, with a variety of control algorithms and control modes, and the closed-loop control method is more stable and reliable. With the development of automation technology, servo motor technology will have more application scenarios and development space.

First, the application of motor power regulation

Motor power regulation is mainly used in the need to adjust the motor speed according to the size of the workload, such as production lines, industrial machinery, ships and so on. In some places where energy saving and consumption reduction is required, the energy consumption structure can also be optimised by adjusting the motor power.

Second, the motor power adjustment method

1. Artificial regulation

Artificial regulation that is, through human operation to adjust the power of the motor. There are mainly the following two adjustment methods:

(1) manual knob adjustment: turn the manual knob to the corresponding position to change the output power and speed of the motor.

(2) Manual remote control adjustment: Adjust the output power and speed of the motor by manual remote control to achieve wireless remote control.

2. Automatic adjustment mode

The automatic adjustment method is to realise the power adjustment of the motor through the computer, PLC controller and other automatic devices. There are mainly the following two regulation methods:

(1) PID control: PID control, i.e. proportional, integral and differential control, uses sensors to detect changes in material load and adjust the speed to meet the needs of different workloads.

(2) Frequency control: Frequency control is to change the traditional AC power supply into frequency-adjustable AC power supply, which can achieve the voltage and frequency of the motor to regulate the motor, so as to effectively control the output power and speed of the motor.

Third, the advantages of motor power regulation

1. can achieve energy saving and reduce the energy cost of the motor.

2. can effectively extend the service life of the motor, reduce equipment loss.

3. can improve the efficiency of the motor, increase the production efficiency.

In short, the choice of motor power regulation method mainly depends on the specific application scenarios and needs, manual regulation and automatic regulation of the two ways have their own advantages and scope of application. In the actual application process, it is necessary to combine the actual situation to choose. Definition of automatic generator voltage regulator: a synchronous generator regulator that maintains the synchronous generator voltage at a predetermined value or changes the terminal voltage according to a plan. When the terminal voltage and reactive power of the synchronous motor change, the output current of the exciter is automatically controlled according to the corresponding feedback signal to achieve the purpose of automatically adjusting the terminal voltage or reactive power of the synchronous motor.

Synchronous generator voltage automatic regulator (AVR) can be divided into: thyristor automatic voltage regulation, TD1 type carbon resistance automatic voltage regulation, phase re-excitation automatic voltage regulation and other three types. The following are the three types of synchronous generator voltage automatic regulator principle of operation.

1. silicon controlled automatic voltage regulation

This regulator refers to the use of series or parallel to the excitation circuit of the thyristor to control the excitation current, so that the generator's output voltage with the load changes and automatic regulation. Thyristor control has a variety of ways: one is the use of single junction transistor oscillator circuit to generate a trigger pulse, change the capacitor charging voltage, thereby controlling the trigger pulse generation time, change the SCR conduction angle; the second is the use of transistor switching characteristics, change the capacitor charging voltage, control the transistor conduction time to generate a trigger pulse, the same can also be controlled by the conduction angle of the SCR.

2. TD1-type carbon resistance automatic voltage regulation

This type of voltage regulation is used in 6135ZD diesel generator set, its working principle is: when the generator load for the rated value, the voltage automatic regulator to maintain a stable immobility, when the generator's excitation current, voltage and the main excitation current are stable and unchanged. The load of the motor increases, resulting in voltage reduction, the voltage regulator begins to adjust the carbon chip resistance, so that its resistance value decreases, so that the generator's excitation current increases, prompting the generator's output voltage; Conversely, when the load decreases, the voltage regulator will adjust the carbon chip resistance increases, so that the excitation current decreases, prompting the voltage to fall.

3. phase re-excitation automatic voltage regulation

For the starting and operation of the load changes in the special equipment, the use of phase re-excitation automatic voltage regulation is better, so at present in the special equipment power supply, generator control part of the more used phase re-excitation automatic voltage regulation. The basic principle of phase re-excitation automatic voltage regulation is: when the generator is unloaded, the residual magnetism voltage of the armature tap winding is shifted by 90° through the linear reactor, and after rectified by the three-phase bridge rectifier, the output DC current flows to the magnetic field winding for excitation. When the remanent magnetisation voltage is too low, it can be charged by DC. When the generator with a load, its load current through the primary winding of the current transformer to produce a secondary current and the primary winding current proportional to the relationship between the secondary current, this current can be different power factor with the load changes in the size of the required excitation current and the corresponding increase or decrease. Under the appropriate parameters, the generator is supplied with the required excitation current, so it can automatically adjust the voltage, so that the voltage remains stable within a certain range. Because of this characteristic, it is used more in engineering construction and special equipment.