An IGBT-Based Pulsed Power Supply in the Fabrication of Non-Contiguous Nanofibres Using Electrospinning

Nanofibres are useful in many areas due to their outstanding characteristics: small size and high surface-to-volume ratio. Recently, drug delivery systems using polymer nanofibres have gained significant attention. For these systems, a chopped nanofibre is required because the amount of drug released depends on the length of the fibre. Electrospinning is the simplest method of fabricating polymer nanofibres. In the process, a high voltage creates an electrified jet which eventually becomes a nanofibre. The jet ejects when a high voltage is applied and vice versa. It is therefore possible to fabricate and chop nanofibres by controlling the value of the voltages applied. In this research, an IGBT-based pulsed power supply has been designed and built. The IGBTs are connected in series to increase a withstand voltage. The power supply can produce square pulses with a width of a few hundred microseconds to DC and amplitudes up to 10 kV. The technique of non-continuous-mode electrospinning using the pulsed power supply was able to fabricate and chop nanofibres with PEO. The minimum pulse width that can initiate a jet is approximately 80 ms in this study. A jet is always ejected during the pulse-on voltage when the duty ratio is more than 40%.