Application Status of Inverter in Industrial Equipment

Inverter is more and more widely used in industrial equipment. Inverter shows good control characteristics in the application of mechanical equipment, which can effectively realize soft start and stepless speed regulation of industrial equipment, and make industrial equipment accelerate The deceleration is effectively controlled, which greatly improves the performance and automation of industrial equipment. In recent years, frequency converters have been widely used in industrial production. There are some problems in the process of using frequency converters, which will seriously affect the performance of industrial equipment. Relevant personnel must pay attention to the maintenance of frequency converters and take effective measures to solve the problems of The problems existing in the application of equipment can ensure the good performance and longer service life of industrial equipment.

1. Low subharmonics seriously affect industrial equipment loads.

At present, the main circuit form of frequency converters used in industrial equipment can generally be divided into three parts, namely rectification, inverter and filtering. The rectification part of the main circuit of the inverter is a three-phase bridge uncontrolled rectifier, and the intermediate filter part of the inverter usually uses a larger capacitor as a filter. The inverter part of the frequency converter uses an IGBT three-phase bridge inverter, and the waveform of the inverter part is input by PWM waveform. In addition to the fundamental wave, the output voltage of the frequency converter commonly used in industrial equipment also contains other forms of harmonics. If there are lower harmonics, it will have a great adverse effect on the load of industrial equipment. If there are higher Harmonics will greatly increase the oil leakage of the frequency converter in industrial equipment, which will cause the operation of industrial equipment to be blocked. When the frequency converter of industrial equipment outputs high and low harmonics, relevant personnel have not taken effective measures to suppress them. It will affect the normal use of industrial equipment inverter.

2. Noise and vibration cause resonance in various parts of industrial equipment.

During the use of industrial equipment, the use of frequency converters for speed regulation will generate noise and vibration. This is mainly due to the fact that the waveform output by the frequency converter contains high and low harmonics during the working process, which will make the frequency converter work. generate noise and vibration. With the change of the operating frequency of the frequency converter, the higher harmonics of the frequency converter have changed in a large range, and the noise and vibration generated will make all parts of the industrial equipment resonate. When using a frequency converter to regulate the speed of industrial equipment, the output voltage and current of the frequency converter contain high-order harmonics. As the magnetic flux of high-order harmonics gradually increases, the noise generated will gradually increase. When the frequency converter in industrial equipment is working, the higher harmonics in the output waveform will cause the magnetic field to generate a certain electromagnetic driving force on various parts of the industrial equipment. When the electromagnetic driving force generated by each part of the industrial equipment and the natural frequency of the industrial equipment components When coincident or close, resonance will occur, which will cause malfunction and damage of industrial equipment in the long run, seriously affecting the normal use of industrial equipment, not conducive to the normal operation of industrial equipment, and reducing the service life of industrial equipment.

3. Overheating of the inverter will damage the inverter.

During the process of speed regulation of industrial equipment, the frequency converter will generate a certain loss inside, which will make the frequency converter heat up. The internal circuit of the frequency converter is mainly composed of circuits, accounting for about 98%, and the control circuit of the frequency converter accounts for about 2 %, in order to make the frequency converter operate normally in the speed regulation of industrial equipment, effective measures must be taken to dissipate heat from the frequency converter, so as to prevent the frequency converter from malfunctioning due to excessive heat during operation. When the internal components of the inverter in industrial equipment fail, the rectifier module and inverter module of the inverter are easily damaged. It is easy to judge whether the rectifier module of the inverter is damaged. When there is no short circuit in the inverter, Just replace the rectifier bridge in time. When the inverter module part of the inverter is damaged, it is difficult to judge whether it is damaged. The main cause of damage is caused by the outside of the inverter and the quality of the inverter. Usually, after repairing the drive circuit of the inverter, Only when the driving waveform is good can the inverter module be replaced. However, under normal circumstances, the relevant staff did not discover the failure of the inverter components and some modules in time, and did not realize the damage caused by the overheating of the inverter to the inverter itself.