Historical inquiry: wartime influences on the power system

[brainsalad]

Greetings:

What knowledge can you share about how the war (most interestingly World War II) changed the way power systems operate?

Some examples which I have found,
-the increased use of capacitors in industrial plants
-the decrease in 600-V equipment, despite its economy
-tapped transmission lines and the need for differential protection

Thanks for your thoughts!

 

[waross]

A common distribution voltage was 2400 Volts delta. With the increase in demand with industrial, commercial and residential expansion after the war, the 2400 Volt distribution circuits were becoming overloaded. Many utilities switched to 4160 Volt wye distribution. By stringing a bare neutral conductor and reconnecting the existing transformers, the capacity of a distribution circuit could be increased by 73%.
They then discovered some of the idiosyncrasies of a wye:delta transformer bank when the primary neutral is connected.
Some utilities went to floating the primary wye point and discovered some new issues. Mostly all wye:wye now.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[prc]

Please see AIEE Transactions Vol66 1947 The German Electrical Utility Industry during world war II by John G Noest and discussions there after.

The war made it clear to governments the need for interconnectivity of grid, reliabilty issues,overloading requirements in case of emergencies.

My fond memory with regard to transformers- during war period US Government wanted some medium sized transformers urgently for war production.Since there was acute shortage of copper, government released few tonnes of silver from treasurey to make transformer windings.After the war,of course, the transformers were scrapped and the silver returned to US coffers.

 

[magoo2]

To clarify some of Bill's points, the 3-wire delta circuits were surpassed by the 4-wire multi-grounded neutral circuits much before WWII. The REAs, which funded the rural electric cooperatives in the US, went to 12.47 kV in the early 30's and the larger utilities soon saw the advantages of the 4-wire system and started using it.

The conversion of 2400 V delta circuits to 4.16 kV wye also predated WWII by a decade or more.

Today's preferred distribution design is 4-wire multi-grounded neutral. However, if you see what types of distribution are in California, they still have a mix of a considerable amount of 3-wire delta circuits in addition to 4-wire circuits. The other 49 states have mostly 4-wire distribution.

 

[waross]

Hi magoo2
I didn't realize that the conversion started that early in some areas.
Our little local utility (Okanagan Valley, Western Canada) went from 2400 V delta to 4160 V wye in the 50's.
Thanks for the information.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[BJC]

Silver was used in substation bus bars to replace copper and aluminum.
It's use in transformers was rare.
The type HH copper transmission line from Boulder dam to LA was on it's was to replacement before war was declaired.