182 / 2022-03-14 16:47:52

The Development of Bipolar Marx Pulse Generator Based on Magnetical Isolated Driver

Pusled power technology, bipolar pulse, Marx circuit, magnetic isolated driver, solid-state switches

Purpose/Aim

In the field of liquid food sterilization, the main mechanism of sterilization is the irreversible perforation and death of microorganisms in food induced by high pulsed electric fields (1-100 μs, 20-80 kV/cm). In addition to the intensity and duration of action of the pulsed electric field, the alternating stress generated by the bipolar pulses makes the structure of the cell membrane fatigue, the permeability of the cell membrane increases, and the sterilization effect is effectively enhanced. Also, metal electrodes are often used for high voltage electrodes during food sterilization processing. The unipolar pulses output is prone to electrode corrosion and thus food safety problems. Compared with unipolar pulses, bipolar pulses can effectively inhibit electrode corrosion and ensure food safety by switching polarity.

Experimental/Modeling methods

In this paper, a dual MARX circuit structure is selected as the bipolar pulse generator topology and a magnetically isolated drive circuit for the switch is designed. Compared with the conventional fiber-optic isolated drive circuit and magneto-isolated drive circuit, this drive circuit has a simple structure and only requires two control signals to achieve the control requirements of the four types of switches. It makes the stability and reliability of the control system greatly improved.

Results/discussion

Bipolar pulse generator based on magnetically isolated drive circuit can output pulse width 3~10us, pulse interval, pulse frequency 0-200Hz, pulse amplitude 0~±20kv flexibly adjustable.

Conclusions

For the traditional bipolar pulse source output is limited by the isolation drive The bipolar Marx pulse source based on magnetic isolation drive has been developed to address the problem of high amplitude output due to the limitation of isolation drive, which has high and flexible output parameters. It will be own good prospects for application in food sterilization.