Servo drive is used to drive servo motors, servo motors can be stepper motors, can also be AC asynchronous motors, mainly for the realization of fast, precise positioning, such as the kind of stop and go, high precision requirements of the occasion with a lot.
Frequency converter is in order to frequency AC power into suitable for adjusting the speed of the motor current, used to drive the motor, and now some frequency converter can also be realized servo control, that is, you can drive the servo motor, but the servo drive and frequency converter is still not the same! Can servo and inverter difference is exactly what, please see the editor for your decomposition.
Frequency converter is the use of power semiconductor devices on and off the role of the power frequency power supply into another frequency of electrical energy control devices, can realize the AC asynchronous motor soft start, frequency speed control, improve the operating accuracy, change the power factor and other functions. Frequency converter can drive inverter motor, ordinary AC motor, mainly as the role of regulating motor speed. Frequency converter usually consists of four parts: rectifier unit, high-capacity capacitor, inverter and controller.
Servo system is an automatic control system that enables the output controlled quantities such as the position, orientation and state of an object to follow the arbitrary change of the input target (or given value). The main task is according to the requirements of the control command, the power amplification, transformation and regulation and other processing, so that the output torque, speed and position control of the drive device is very flexible and convenient.
Servo system is a feedback control system used to precisely follow or reproduce a process. It is also known as a follower system. In many cases, the servo system refers exclusively to the controlled quantity (the output of the system) is the mechanical displacement or displacement speed, acceleration feedback control system, its role is to make the output mechanical displacement (or angle of rotation) accurately track the input displacement (or angle of rotation). The structural composition of the servo system and other forms of feedback control systems are not different in principle.
Servo systems can be categorized into electromechanical servo systems, hydraulic servo systems and pneumatic servo systems according to the type of drive element used. The most basic servo systems include servo actuators (motors, hydraulic cylinders), feedback elements and servo drives. If you want to make the servo system run smoothly also need a upper body, PLC, and specialized motion control card, industrial computer + PCI card, in order to send commands to the servo drive.
The speed regulation principle of the frequency converter is mainly limited by four factors: the speed n of the asynchronous motor, the frequency f of the asynchronous motor, the rate of motor rotation s, and the number of motor poles p. The speed n is proportional to the frequency f of the asynchronous motor. Speed n is proportional to the frequency f, as long as the frequency f can be changed to change the motor speed, when the frequency f changes in the range of 0-50Hz, the motor speed adjustment range is very wide. Frequency conversion speed regulation is realized by changing the frequency of motor power supply.
It mainly adopts the AC-DC-AC method, which first converts the industrial frequency AC power supply into DC power supply through rectifier, and then converts the DC power supply into AC power supply with controllable frequency and voltage for supplying the motor. The circuit of frequency converter generally consists of four parts: rectifier, intermediate DC link, inverter and control. The rectifier part is a three-phase bridge uncontrollable rectifier, the inverter part is an IGBT three-phase bridge inverter, and the output is PWM waveform, and the intermediate DC link is filtering, DC energy storage and buffer reactive power.
The working principle of the servo system is simply in the open-loop control of AC and DC motors on the basis of speed and position signals through the rotary encoder, resolver, etc. feedback to the driver to do closed-loop negative feedback PID regulation and control. Coupled with the driver's internal current closed-loop, through the three closed-loop regulation, so that the motor's output to the set value of the accuracy and time response characteristics are improved a lot. Servo system is a dynamic following system, the steady state equilibrium achieved is also a dynamic equilibrium.