תכנון וניהול משק החשמל
Estimating the inertia in the Israeli grid and its implications to stability and robustness
The inertia in the grid is often used as a proxy for grid robustness and, in particular, its ability to recover from contingency events (e.g. faults) that threaten to reduce the grid’s frequency below its normal operating range. This is particularly important in short time-scales, before primary control sets in.
Renewable electricity generation is rapidly growing all over the world due to several factors including government support, consumer preferences, climate change concerns, and falling capital costs. Renewable energy generators depend on intermittent resources, and are connected to the grid through inverters, thus contributing no inertia. Hence, the increased penetration of renewable sources has brought with it serious concerns about grid stability and robustness
Transmission system operators in Europe, USA, Canada, and Australia are developing and implementing reliable tools to estimate the inertia in the system, and to mitigate the effects of increased penetration of renewable sources on the inertia. To the best of our knowledge, these tools have not been developed nor used in the Israeli grid
The planned research will focus on the following goals :
- developing new theoretical and practical tools for off-line and on-line inertia estimation
- analyzing the effect of inertia on the grid stability and robustness
- building both simulations and a real micro-grid to validate the inertia estimation tools
applying these tools to the Israeli grid and using them to :
- predict the effect of renewable energy penetration on its robustness
- analyze the efficiency of various tools for mitigating low inertia such as using inverters with virtual inertia
The research would aid the Israeli grid operator to plan for the future and determine how many inertia-less power sources to allow into the system, and how to mitigate their effects on the grid stability, for instance by requiring that certain proportion of inverters should be virtual synchronous machines. In particular, it could aid the Electricity Authority to develop new regulations pertaining to inertia. Overall, this would facilitate large-scale integration of renewable energy sources into the Israeli power grid.