Nanosecond Pulsed Electric Fields (nsPEFs) Low Cost Generator Design using

Power MOSFET and Cockcroft-Walton Multiplier Circuit as High Voltage DC

Source

Muhammad Yangki Sulaeman and Rena Widita

Department of Physics, Nuclear Physics and Biophysics Research Group Faculty of Mathematics and Natural Science

Institut Teknologi Bandung, Bandung, Indonesia

OUTLINE

Introduction Methodology

Result and Discussion Conclusion and Future Works

INTRODUCTION

7.6 million people worldwide died from cancer in 2008

70% of cancer death occurs in low- and middle-income

countries

Estimated 170-190 new cancer cases annually for each 100.000

people in Indonesia

Ionizing Radiation Therapy

Non-ionizing Radiation Therapy?

Membrane cell

Applied pulsed electric field

Pore formation in membrane cell

Introduce genes or anti-cancer drugs to cancer cell

Trigger apoptosis or necrosis to cancer cell

Commercial available high voltage pulsed generator

Commercial available high voltage pulsed generator

Objective of the main research

Build nanosecond pulsed electric field (nsPEFs) low cost generator

Simulate the electroporation mechanism in animal cells (unfinished work) (unfinished work)

Objective of the main research

Build nanosecond pulsed electric field (nsPEFs) low cost generator

Simulate the electroporation mechanism in animal cells (unfinished work) (unfinished work)

METHODOLOGY

Simulate prototype schematic using NI MULTISIM 12

Build the prototype based on simulating result

Simulate prototype schematic using NI MULTISIM 12

Low Voltage Pulsed Generator

Driver MOSFET

Power MOSFET

High Voltage Generator

Schematic of High Voltage Generator using Cockcroft-Walton multiplier

HV_output generates high voltage, 1.5 kV

Low Voltage Pulsed Generator

Driver MOSFET

Power MOSFET

High Voltage Generator

Schematic of Schmitt trigger to trigger driver MOSFET using different form of 5 volt pulses in OUTPUT_1 and OUTPUT_2

Non-inverting amplifier to amplify the two outputs voltage from Schmitt trigger.

Output voltages from OUT_1 and OUT_2 is around 15 volts.

Low Voltage Pulsed Generator

Driver MOSFET

Power MOSFET

High Voltage Generator

Driver MOSFET for trigger the fast switching in power MOSFET.

Output voltage from OUT is around 15 volts.

Low Voltage Pulsed Generator

Driver MOSFET

Power MOSFET

High Voltage Generator

Fast switch using four series Power MOSFET with 50Ω load.

Output voltage at load (R8) is 1.5 kV.

Simulate prototype schematic using NI MULTISIM 12

Build the prototype based on simulating result

Build the prototype based on simulating result

Prototype of Cockcroft-Walton multiplier as high voltage generator.

Prototype of Amplified Schmitt trigger to trigger the driver MOSFET.

Prototype of Power MOSFET with 50Ω load.

RESULT AND DISCUSSION

Prototype Result – Output from amplified Schmitt trigger

Prototype Result – Output from driver MOSFET

Prototype Result – Output in 50Ω load

CONCLUSION AND FUTURE WORKS

High voltage generator based on this design is not able to generate high voltage output on 50Ω load as we expected, based on our experiment it only generates 400 volts output.

The Cockcroft-Walton multiplier in this design cannot withstand the input voltage from AC source due to the voltage rating and capacitance of the capacitors.

However, it is able to generates pulse with 400 volts with 200 nanosecond width that can be regulated by changing the value of resistor in Schmitt-Trigger and it still can be used for electroporation purposes if we change the 50 Ω load with electroporation cuvette.

Total cost for this research do not exceed 200.000 IDR, all the component can be found in our local electronic shop, except for LM7171 that used for amplification the Schmitt-Trigger output.

For the future works, we will modify the Cockcroft-Walton multiplier schematic to ignore the output voltage drop. Capacitors with high capacitance and voltage rating will be used, but the total cost for new schematic also will be increased.

LM7171 will be replaced by another OP-AMP that have same properties but available in local store to create a design with easy obtained components.

It also need to improve the prototype by adding a shielding box and replace the old circuit board into compact circuit board for safety reason.

REFERENCES

[1] World Cancer Day 2013. [cited 2013 29 August]; Available from: http://www.who.int/cancer/en/ [2] Tjindarbumi, D. and R. Mangunkusumo, Cancer in Indonesia, present and future. Jpn J Clin Oncol, 2002. [3] Schellekens, M.C., et al., Prevalence of single and multiple HPV types in cervical carcinomas in Jakarta, Indonesia. Gynecologic oncology, 2004. [4] Rubinsky, B., Irreversible electroporation. Series in biomedical engineering,. 2010, Berlin: Springer. [5] Kee, S., Clinical aspects of electroporation. 2011, New York: Springer.

[6] Dwivedi, C. and M. Daigvane. Multi-purpose Low Cost DC High Voltage Generator (60kV Output), Using Cockcroft- Walton Voltage Multiplier Circuit. in Emerging Trends in E ngineering and Technology (ICETET), 2010 3rd International Conference on. 2010. IEEE. [7] Brugler, J., Theoretical performance of voltage multiplier circuits. Solid-State Circuits, IEEE Journal of, 1971. [8] Grenier, J.R., Design of a MOSFET-Based Pulsed Power Supply for Electroporation. 2006: University of Waterloo. [9] Baker, R. and S. Ward, Designing nanosecond high voltage pulse generators using power MOSFETs. Electronics Letters, 1994. 30(20): p. 1634-1635.