1st quarterly report at KEMA Labs

The Australian electricity supply industry is in the midst of a rapid transition to an electricity network with a high penetration of renewable generation reliant on inverter-based resources to connect these to the grid. Many obstacles to facilitate this future have already been overcome, however there are still significant challenges associated with moving away from the traditional synchronous generation that has reliably powered the electricity industry for a number of decades.

During my time as an ES Cornwall Scholarship holder I hope to explore a number of these challenges and learn from some of the leading European organisations in this field to help grow my capabilities and understanding of how Europe intends to complete this transition. I am hoping to return to Australia with this knowledge that will not only help me in my day-to-day nominal role, but also I am hoping to share my experiences more broadly to express gratitude for this opportunity that has been afforded me.

This quarterly report is the first of four reports I will submit during my time as an ES Cornwall Scholarship holder and covers my first three months with KEMA Labs. During this period I was also fortunate enough to attend the 2022 CIGRE Paris Session therefore I have also included my takeaways from this session in the report.

In these three months, I have been involved in a number of projects at KEMA Labs relating to the development and performance of testing on inverter-based devices such as battery chargers and solar inverters. This testing has involved a combination of simulation/modelling and physical testing and hardware-in-the-loop testing has been implemented on occasion. A summary of the lessons learned during these projects is as follows:

  1. Silicon controlled rectifier (SCR) thyristors provide different advantages to the more common insulated-gate bipolar transistor (IGBT) transistors in terms of their performance in a rectifier bridge. While SCRs can be cheaper and possibly more efficient than IGBTs for high power
    applications, they often require a stronger incoming reference signal and therefore may struggle in weaker networks.
  2. Testing of inverter-based devices may require a sufficiently strong source, such as a diesel generator, which may make power amplifier based testing (and therefore common power hardware-in-the-loop setups) not possible. This is a result of inverter-based equipment distorting
    the incoming AC signal and introducing transients that may cause instabilities in the system.
  3. The differences between two common real-time simulators, RTDS and OPAL-RT, and how these can both be used for in-the-loop testing.
  4. Best practices for power-hardware-in-the-loop testing including recommended protection, restrictions on model and controller timesteps and the typical test execution procedure.

I will remain in my role at KEMA Labs until the 24
th of March during which time I will continue working in similar areas with the testing of a battery storage system currently planned for January. Following this, I will be moving across to the United Kingdom to undertake a role with National Grid ESO.

A full version of this report can be found here.