The spindle of a traditional grinder is directly operated by the power frequency, and the spindle grinding wheel motor operates according to the traditional starting circuit. When the gate voltage fluctuates, the grinding wheel spindle speed fluctuates, affecting the grinding accuracy of the workpiece. Therefore, from the perspective of improving processing quality and processing efficiency, applying variable frequency speed regulation technology to grinders can achieve satisfactory results. However, due to the disadvantage of poor environmental resistance of general economical inverters, they are increasingly unable to meet the on-site requirements of grinders. Therefore, high-performance vector economical inverters with low frequency, high torque and high protection level have become the needs of on-site applications of grinders.

Process requirements:

A grinder is a machine tool that uses abrasive tools to grind the surface of a workpiece. Most grinders use a high-speed rotating grinding wheel to grind the workpiece. The high-speed rotating spindle is controlled by an economical inverter, and the requirements are as follows:

1. For low-frequency processing, the torque is larger. When the grinder is roughing, the spindle needs to run at a low frequency. When the general economical inverter runs at a low frequency, the torque is small and cannot be processed. Therefore, the economical inverter is required to have the characteristics of low frequency and high torque.

2. Stepless speed regulation of spindle operation. The spindle adjusts different operating speeds according to the requirements of the workpiece, requiring the economical inverter to have stepless speed regulation capability.

3. High-precision working speed. The high-speed rotation accuracy of the spindle directly affects the accuracy of the grinding workpiece, so the driving economical inverter must have high-speed precision

4.The protection level is very high. The grinding machine processing environment is a high oil pollution, high dust, high air humidity environment. The economical inverter needs to have a higher protection level, otherwise it will cause short circuit damage or even machine explosion.

5.The motor has low vibration and noise.

System solution:

1. Solution Selection

According to the technological requirements of the grinding machine, a j600 series closed-loop vector converter with a high protection level is selected, and the power of the converter matches the power of the driven motor.

2.Brief Introduction of Economical Frequency Converter

A high protection level closed-loop vector converter specially developed on a new software and hardware platform. It has superior performance, compact structure, complete protection functions, rich and flexible peripheral interfaces and functions, can adapt to various harsh environments such as humidity and dust, etc., and can be flexibly developed for all industrial applications according to on-site conditions. It has the following characteristics:

（1）High and low frequency torque. Closed loop vector zero speed can reach 200% of starting torque, open loop vector zero speed can reach 180% of starting torque;

（2）In high frequency working mode, the maximum base frequency output is 1000.0hz;

（3）Built-in multiple system macros and application macros, which can be called through macro parameters and parameter settings are simplified;

（4）The priority of the frequency/speed setting channel can be flexibly configured;

（5） Rich warning and protection functions;

（6）High protection grade IP54, can adapt to various harsh environments such as moisture and dust.