Abstract: Delta's VE series frequency converters are high-end frequency converters launched by Delta for machine tools, elevators, printing, wire drawing, and other applications. In particular, their precise single-point and multi-point positioning, robust position tracking, and outstanding dynamic response characteristics have made them popular among CNC center manufacturers.
Keywords: frequency converter, position tracking, positioning
introduction:
One of the most common tapping methods used on CNC machine tools today is "rigid tapping," also known as "synchronous feed tapping." Rigid tapping cycles synchronize spindle rotation and feed to match specific thread pitch requirements. If the spindle rotation and Z-axis feed are always synchronized, tapping accuracy can be guaranteed. This method is called "rigid tapping." In this case, the spindle's operation changes from a speed system to a position system. Therefore, based on the definition of rigid tapping, we can conclude that to achieve rigid tapping, the spindle drive system must have position control capabilities, with the CNC system controlling the Z-axis feed and the spindle position.
I. Introduction to Delta VE Series Frequency Inverters
The VE series frequency converters are designed by Delta Electronics to meet the application needs of CNC machining centers, making them ideal for such applications.
1. The high-speed version of the frequency converter can achieve stable operation at 3600HZ.
2. It can achieve fast single-point and multi-point positioning through external I/O points, and has special parameters to adjust the positioning characteristic curve and positioning time, making it convenient to implement.
3. Rapid acceleration and deceleration are achieved through the adjustment of dedicated parameters, thus meeting the requirements for rapid response.
4. The brand-new PDFF control makes gain adjustment simpler, more convenient, and easier to master.
5. It can introduce analog quantities and pulse position signals, thereby realizing the position tracking function.
6. Automatic adjustment of low-speed and high-speed bandwidth, so that the gain of its speed loop and position loop is more suitable for the needs of the field load.
The VE series frequency converters, with their constant tension control function, have significant potential for development in the printing and wire drawing industries. They can achieve:
1. Tension control scheme in tension closed-loop speed mode
2. Tension control scheme of tension closed-loop turning mode
3. Tension control scheme in open-loop tension control mode
II. Hardware block diagram for rigid tapping using Delta VE frequency converter
The system wiring diagram for pulse command following is as follows:
Delta's VE series analog inputs have reached a resolution of 12 bits. The analog input wiring diagram is as follows:
III. Commissioning Steps for VE Frequency Converters
Step 1: V/F Trial Run
Step 2: Motor parameter measurement
Step 3: Vector Control
After auto-tuning is complete, please check the relevant parameters.
【05-05】à No-load current (approximately 30%-50% of the rated current)
【05-06】àRs
【05-07】àRr
【05-08】àLm
【05-09】àLx
Step 4: Perform inertia estimation function
4.6 Step 6: Set the relevant inverter parameters according to system requirements.
IV. Monitoring software配套 with VE
The VE series frequency converters not only boast superior performance, but also offer a variety of on-site data acquisition and waveform acquisition methods. They can directly present relevant operating data to customers without the need for an oscilloscope, facilitating on-site commissioning personnel in debugging and troubleshooting.
VFD-VE motor software is a monitoring software specifically designed for the VE series inverters, and it's also a very practical digital oscilloscope software. Through this software, we can intuitively view relevant data, thus better judging the exceptional performance of the VE series inverters. The following image shows the waveform at the field. From the waveform, we can clearly see that the inverter's output frequency always follows the set frequency of the corresponding CNC system. As the frequency changes, its current operation remains remarkably stable.
V. Conclusion
The VFD-VE frequency converter represents a masterpiece of advanced control technology, especially with its superior performance similar to servo drives, coupled with a significant price advantage over servo drives in high-power applications. Therefore, it is increasingly favored by industry professionals in China's machine tool sector. Furthermore, with Delta Electronics' extensive field application experience and efficient service system, it will be the preferred product for all machine tool, printing, and wire drawing industries.
