Failure of a meshed power system cannot be attributed to the failure of any single sub-system. Rather it must be a combination of factors including those you just mentioned.
The dependence of the power system on renewables (specifically wind farms)contributed in two ways to the blackout:
1. The majority of wind turbines provide little or no system inertia. By displacing synchronous generation with wind generation, system inertia is reduced which results in greater ROCOF during an event where there is a change in active power demand/supply. In the SA blackout, fast ROCOF overwhelmed the system's last line of defence- under frequency load shedding.
2. Some wind turbines contained a fault ride-through setting which AEMO was apparently not aware of prior to the blackout. Specifically, the setting caused the turbines to disconnect after experiencing a sequence of voltage excursions within a set time period. The disconnection caused a loss of active power supply to the grid which contributed to the drop in frequency and eventual collapse.
https://www.aemo.com.au/-/media/Files/Electricity/NEM/Market...
Failure of a meshed power system cannot be attributed to the failure of any single sub-system. Rather it must be a combination of factors including those you just mentioned.
The dependence of the power system on renewables (specifically wind farms)contributed in two ways to the blackout:
1. The majority of wind turbines provide little or no system inertia. By displacing synchronous generation with wind generation, system inertia is reduced which results in greater ROCOF during an event where there is a change in active power demand/supply. In the SA blackout, fast ROCOF overwhelmed the system's last line of defence- under frequency load shedding.
2. Some wind turbines contained a fault ride-through setting which AEMO was apparently not aware of prior to the blackout. Specifically, the setting caused the turbines to disconnect after experiencing a sequence of voltage excursions within a set time period. The disconnection caused a loss of active power supply to the grid which contributed to the drop in frequency and eventual collapse.