Power Converter Design for Pulsed Electric Field-Based Milk Processing: A Proof of Concept.

Area of Science:

• Food Science and Technology
• Electrical Engineering
• Biotechnology

Background:

• Traditional heat pasteurization of milk negatively impacts sensory qualities.
• Emerging technologies are needed for milk innocuity and sensory profile preservation.
• Pulsed electric field (PEF) processing is a promising low-temperature alternative.

Purpose of the Study:

• To design and simulate a converter for generating pulsed electric fields (PEF) for milk processing.
• To ensure the generated PEF meets the electrical impedance characteristics of milk.
• To validate the converter's performance under varying milk impedance conditions.

Main Methods:

• Modification of a Vienna rectifier by incorporating a Multilevel Boost Converter (MBC) structure.
• Simulation of the proposed converter using PLECS software (version 4.9.6).
• Implementation of a control law for voltage regulation (kV range) and random switch activation in MMC arrays to mitigate transients.

Main Results:

• The designed converter successfully generated high-voltage pulses suitable for PEF processing.
• Simulations demonstrated the converter's ability to adapt to changing milk impedance.
• The control strategy effectively regulated voltage and managed switching transients.

Conclusions:

• The proposed converter design is a feasible proof of concept for PEF milk pasteurization.
• PEF processing offers a viable alternative to heat treatment for maintaining milk quality.
• Further development could lead to efficient and effective low-temperature milk pasteurization systems.