1 Introduction
Conveyor belts are the most commonly used equipment in the processing and manufacturing industry, especially in the highly automated companies where the speed stability of the conveyor belt is very high. If the load on the conveyor belt is heavy, it will easily cause speed fluctuations, which will sometimes have a certain impact on the user's normal production.
The VVC+ vector control method of HLP-SV series inverter adopts PID closed-loop control method, which can automatically adjust the output frequency of the inverter and keep the motor's rotation speed constant. When there is speed fluctuation, the speed of the motor is automatically adjusted to reach a constant speed. Requirements, the general motor speed <1500 rpm, the maximum error of ± 1.5 rpm;> 1500 rpm, the maximum error is 0.1% of the actual speed.
2, system requirements
The conveyor belt is driven by two motors. The operating speed requirement is 700 rpm (maximum error is 2 rpm), acceleration and deceleration time is 5S, the motor has pulse feedback (120 pulses per revolution), the conveyor belt control system has an emergency stop function, fault alarm function , Conveyor belt speed can be adjusted.
Conveyor belt motor parameters are as follows: rated power 2.2KW, rated voltage 380V, rated frequency 50Hz, rated speed 1430rpm. If the acceleration/deceleration time is short, add braking resistor
3, system design
According to system requirements, the structure diagram is shown in Figure 1.
(1) console description:
(2) Set the inverter parameters
According to the motor setting motor parameters, and motor self-learning, the other parameters of the inverter are set as follows:
(3) debugging process
1) Fine tune 1#, fine tune 2# to zero;
2) Adjust the speed control potentiometer to the required frequency;
3) Press start/stop button, frequency converter 1#, 2# operation;
4) Observe whether the tachometers 1 and 2 have errors, and if so, adjust them;
5) Conveyor belt load, observe the tachometer 1 #, 2 # whether there is an error, if the frequency converter 1 # is slow, then adjust the fine-tuning 1 #, if the frequency converter 2 # slower adjustment fine-tuning 2 #;
6) If there is still a certain speed fluctuation, you need to adjust the inverter 7-3* group parameters;
7) Please ground the inverter reliably according to the electrical code.
4 Conclusion
SV series vector inverter has large torque at low frequency, fast response, high precision and beautiful appearance design. It not only has the parameter download/upload function, which greatly facilitates the setting of user parameters, but also has the AMA function. It is highly adaptable to various motors and has a very high cost performance.