Re: Very smoky XPT

[mauried@commslab.gov.au (Maurie Daly)]

>>
>>Not totally related to XPT smoke , but does anyone know exactly how the XP 
>>power cars provide HEP for the rest of the train.
>>I know they use an auxiliary generator which is driven by the main engine,but 
>>if this is the case how is the frequency maintained over the rev range of the 
>>engine , static invertors possibly.

> I dont know the exact values, but the HEP alternator is connected to
>the main engine shaft. The voltage and frequency to the train power line
>vary with engine speed. From 100v 25Hz to 300v 60+Hz or there abouts.

> The lights run from a DC battery backed supply with the batteries charged
>by a charger connected to the trainline. The Air Con motors have change
>over contacts that vary the motor winding connections as the voltage and
>frequency of the trainline rises.
> 
> The power car end is simple, at the expense of complexity in each car.
>30 years ago when the HST was designed, this was probably the best method.
>Why the XPT stuck with it im not sure, although solid state frequency 
>converters would not have been available in any great power rating when
>the XPT was built. A rotary converter on the power cars would have added
>to much weight.


Yes I suspected something like this , its a pity as it rules out using 
conventional 415 V 3 phase power for the cars if they have to be hauled by 
conventional locos with HEP , or using conventional power cars like PHGs/PHNs 
etc.
I guess any new replacement for the XP power cars will still require the 
oddball HEP requirements.

Do you have any idea what the capacity of the XP HEP gen set is?

thanks
MD