Scientists from Tomsk Polytechnic University, together with colleagues from China, have developed a model of an autonomous power system that, after accidents and sudden load changes, can redistribute power in less than a second and quickly return power supply parameters to normal, increasing grid stability. It works with renewable energy sources and hydrogen storage.
Autonomous power systems are used where there is no connection to a unified power grid. These include, in particular, remote settlements and industrial facilities. Electricity in them can be generated by solar and wind installations, which are connected to the grid via special power converters — inverters.
The problem arises when the load changes sharply or one of the sources suddenly disconnects. At this moment, the frequency and voltage in the grid can change significantly. The developed system reacts not only to the frequency deviation itself, but also to how quickly it changes. If the frequency begins to rise or fall sharply, the inverter immediately forms a control action and regulates the system's operation.
Scientists created a mathematical model and compared three options for controlling an autonomous power system — classical, inverse, and combined. The combined scheme with synthetic inertia showed the best result. In it, one inverter acts as the leader and forms the main parameters of the grid, while the others adjust their power to the current load.
The model was tested on several emergency scenarios. Scientists simulated a load change of 10–20%, the sudden disconnection of one of the inverters, the connection of a new converter, and also a change in the characteristics of the power grid itself.
When connecting a new inverter, the redistribution of active power took less than 0.7 seconds. The difference with other control options was noticeable. With classical control, reactive power stabilization took up to 37.9 seconds, and with inverse control, reactive power distribution could take up to 7.17 seconds.
In the future, scientists want to create an adaptive control system. It should take into account how much energy is left in the hydrogen storage, the parameters of the power grid, and the condition of the equipment.
The next step will be testing the developed system on laboratory prototypes. The research results are published in the International Journal of Hydrogen Energy, which belongs to category Q1 and has an impact factor of 9.2.