PhD Defence Ilman Sulaeman Islahuzzaman | Keeping the Lights On | Electricity you can count on, not just counted

Keeping the Lights On | Electricity you can count on, not just counted

Ilman Sulaeman Islahuzzaman is a PhD student in the department Radio Systems. (Co)Promotors are prof.dr.ir. F.B.J. Leferink, dr.ing. J. Popović and dr.ir. D.J.G. Moonen from the faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS), University of Twente.

Around 655 million people worldwide still lack access to electricity, while more than 2 billion experience unreliable supply. This limits education, healthcare, household well-being, and economic development. Indonesia has made remarkable progress, achieving an electrification ratio exceeding 99.8% across its approximately 17,000 islands. Decentralized renewable microgrids have helped extend access to remote communities. Nevertheless, ensuring their long-term sustainability remains challenging: some systems have ceased operating after only months or a few years, far short of their intended 25-year lifetime.

This thesis examines one important but often overlooked technical issue: electromagnetic compatibility, with a focus on power quality. In small, isolated, and resource-constrained microgrids, cost and rapid deployment are often prioritized over long-term robustness. Combined with harsh operating conditions, long feeder cables, nonlinear appliances, and less robust equipment, these compromises can intensify power-quality problems, accelerate equipment degradation, and threaten system sustainability.

Using field measurements in Indonesia and the Netherlands, together with modelling, simulations, and conceptual analysis, the research demonstrates that supply quality and demand quality should not be considered independently. It therefore proposes a pragmatic concept of balancing supply and demand quality. This does not mean real-time power balancing or optimization. Instead, it means ensuring compatibility between the quality and robustness provided by the supply and the immunity, operating requirements, and conducted emissions of connected equipment. The objective is not an ideal supply, but a sufficiently robust and affordable system that supports typical household and small commercial appliances.

The thesis also emphasizes low-cost, robust, and easily deployable monitoring. Early detection of deteriorating power quality enables timely intervention and can help prevent early failures. By connecting electromagnetic compatibility theory with field realities, this research supports the development of microgrids that go beyond providing electricity by keeping the lights on to create lasting opportunities for the communities they serve.