LSR injection machine RF radiation interference from the inverter’s input cable and output cable. In the case mentioned above of RF conducted emission interference, when there is RF interference current on the input cable of the inverter, as the cable is equivalent to an antenna, it will undoubtedly produce electromagnetic wave radiation and generate radiation interference.
The PWM voltage transmitted on the inverter output cable, rich in high-frequency components, will generate electromagnetic wave radiation and form radiation interference. Radiation interference is characterized by the interference phenomenon becoming serious when other electronic devices are close to the inverter.
According to the basic principle of electromagnetism, three elements must be present to form electromagnetic interference: electromagnetic interference source, electromagnetic interference pathway, and system sensitive to electromagnetic interference.
To prevent interference, hardware anti-interference and software anti-interference can be used. The hardware anti-interference is the most basic and essential anti-interference measure, generally from the anti and put two aspects to suppress interference.
The overall principle is to inhibit and eliminate the source of interference, cut off the interference to the system coupling channel, and reduce the sensitivity of the system interference signal.
The following are the main steps to solve the field interference of LSR vertical injection molding machines.
1. The use of software anti-interference measures: precisely, through the human-machine interface of the inverter down to adjust the carrier frequency of the inverter, the value is adjusted down to an appropriate range. Only the following hardware anti-interference measures can be taken if this method does not work.
2. For the correct grounding, we can see that the site grounding situation is not very good through the specific research site. And the correct grounding can be the system to effectively suppress foreign interference and reduce the equipment itself to the outside world interference. It is the most effective measure to solve the inverter interference.
Specifically, it is to do the following.
(1) the inverter’s main circuit terminal E must be grounded, the ground can be, and the inverter with the standard motor ground, but not with other equipment common ground, must be a separate grounding electrode. The grounding point should be as far as possible from the grounding point of the weak power equipment. At the same time, the cross-sectional area of the inverter grounding wire should be not less than 4mm2, and the length should be controlled within 20m.
(2) other vertical injection molding machine liquid silicone machine mechanical and electrical equipment ground in the protection ground and work grounding should be set separately and grounding electrode, and finally, converge into the electrical grounding point of the distribution cabinet. The shielding ground of the control signal and the shielding ground of the primary circuit conductor should be set separately and grounded separately, and finally, converge into the electrical grounding point of the distribution cabinet.