Sunwoele VFD (Variable-frequency Drive) application in CNC machine tools
Core Tips:
1 Introduction
The development level of CNC machine tools and the percentage of them in metal cutting machine tools are an important indicator of a country's industrial development level and manufacturing level. CNC lathes are an important type of CNC machine tools. After years of development, CNC lathes in China have developed a variety of specifications such as flat bed and inclined bed, and are widely used in the manufacturing industry. At present, the spindles of CNC lathes have widely adopted variable frequency speed control and even asynchronous servo control, which greatly improves the processing efficiency. This article mainly describes the application of Sunwoele VFD (Variable-frequency Drive) in flat bed CNC lathes.
2 Brief introduction to the requirements of the spindle of flat bed CNC lathes
The spindle is an important part of the lathe. The speed and torque of the spindle play a vital role in the processing efficiency, the range of the workpiece to be processed and the processing accuracy of the workpiece. Ordinary lathes use ordinary AC asynchronous motors and gearboxes to achieve multi-speed step-by-step speed change. When switching the speed, it is generally necessary to stop the spindle and shift gears to achieve it. In order to improve efficiency, CNC lathes use variable frequency speed regulation technology, which greatly simplifies the gearbox and realizes stepless speed regulation.
The parameters of the spindle motor of 6136 CNC lathe are as follows:
Selected motor model: VFG132A-50-5.5
Rated power: 5.5kW;
Rated frequency: 50Hz;
Rated voltage: 380V;
Rated current: 13A;
Rated speed: 1400r/min;
Mechanical transmission ratio: 2:3
Processing material: 45# steel;
Actual test performance indicators:
Spindle speed: 200r/min (VFD (Variable-frequency Drive) operating frequency 9~10Hz);
Spindle speed: 450r/min (VFD (Variable-frequency Drive) operating frequency about 22Hz) feed performance and speed.
3 Sunwoele VFD (Variable-frequency Drive) Features
Select Sunwoele VFD (Variable-frequency Drive) HSF600, which has the following features
⑴ The control system is a high-performance vector control VFD (Variable-frequency Drive) based on DSP, and the waveform generation method is asynchronous space vector PWM,
⑵ Provides standard DC 0~10V range adjustable, DC 0~20mA range adjustable, compatible with most CNC system interfaces, and has strong versatility;
⑶ Voltage allowable fluctuation range: ±15%; frequency allowable fluctuation range: ±5%
⑷ Overload capacity: rated current 150%-1 minute, rated current 200%-0.1 second
⑸ Slip compensation: 0~10%, automatic slip compensation
⑹ Provides multi-functional output terminal signals, up to 6 output signals, each with 32 signals to choose from
4 VFD (Variable-frequency Drive) connection and parameter adjustment
The customer selected a 5.5KW/50Hz/380V motor, selected a VFD (Variable-frequency Drive) model of HSF600 HSF600-5R5G/7R5P-T4, and a brake resistor of 780W/75Ω. The V2/V3 terminals of the VFD (Variable-frequency Drive) provide analog speed with the CNC system. V2 is connected to the positive signal of the analog interface of the CNC system, and V3 is connected to the negative signal. The signal is a 0-10V analog voltage signal to control the spindle speed. FWD/REV/COM is the forward/reverse signal terminal of the VFD (Variable-frequency Drive). Usually, the CNC system sends a forward signal FWD or reverse REV to drive the intermediate relay. The normally open contact of the intermediate relay is connected to the VFD (Variable-frequency Drive) FWD/COM or REV/COM, thereby controlling the forward and reverse rotation of the VFD (Variable-frequency Drive).
Debugging parameters: