Thanks for the extra info!

The problem was the state of the ancillary safety systems made them uneconomic to continue to operate. For example the stator spins in a giant pressurized tank of pure hydrogen which requires a lot of precautions, particularly to keep up with current safety standards.

Unfortunately at the time, AEMO was not able to justify enough benefits to replace the units which was why they were simply removed.

Thanks for filling in those gaps Ralph – the Victorian Railways 25 Hz system is something I’ve been working on and off for some time.

I believe they may put shunt reactors in the parts of the system with a lot of renewable generation like west and north in the future to control the volts.

Historically there was 46 MW of motor generator Frequency Changers at Newport Power Station, Yarraville Terminal and Richmond Power Stations to tie the 25hz and 50hz systems.

The early years of the 132 kV transmission network and synchronous condensers is something I’ve got to research more.

The frequency changers are another interesting technology – linked to the Victorian Railways’ adoption of 25 Hz AC for the electrification of suburban trains in the early 20th century.

A complete history is not complete without reference to the earlier units at Malvern and Brunswick TS. These were still operational until recent times when these stations had a major makeover.

And also filling the role of synchronous condensers to some degree were the frequency changers at Newport, Richmond and Yarraville. Whilst they did not quite have the range of the traditional SC’s, they were able to offer voltage support to a good degree.

It gets a little more complex again when the “non-syncronous” inverters only require these additional supports because they are specified to not provide any inertia (for other reasons, baked into the requirements/standards) and follow the grid variations. Its entirely possible to have wind and solar generators include virtual inertia directly into their designs from the start, but thats incompatible with the paper requirements. Its a larger transition to new ways of managing the grid, necessary to support the fluctuating renewable sources that were never considered in the original designs.

And at that point it becomes extremely political.

In Japan they have both 50Hz and 60Hz. The former came from European generators and the latter from US generators. The two networks are linked by DC conversion, but the links only serve as light-load back-up for each other. When Fukushima happened, the 60Hz network could not support the balance of the smashed 50Hz network.

I had a folder full of photos and diagrams of the Templestowe condenser, but I have a sinking feeling that I didn’t bother scanning them when I converted all my notes to digital.