mikerotch

NHTB refugee

Last Notes

2024-06-14 00:15:15 GMT

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The idea that turbines can produce variable power at a constant RPM is something a lot of engineers overlook because most of the time a turbine is connected to a mechanical load like an airplane engine or ship propeller with a fixed power/RPM relationship.
If you're just supplying DC power though then that constraint goes away entirely.

2024-06-14 00:09:38 GMT

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You want the turbine to turn on and operate at its design RPM for as long as possible.
Electrical generators that freed from the constraint of producing a fixed AC output frequency have a very flexible relationship between RPM and power. You can change the torque/power ratio pretty substantially by simply adjusting the field excitation. This allows you to keep your turbine at the design RPM under a very wide range of loads, potentially the entire range.

2024-06-13 23:41:56 GMT

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Yeah turbines would be ideal for the power plant since they are very efficient running at design speed and you can rely on the electrical system to smooth out the demand so they can stay at that speed all the time.
Batteries are a terrible fit for a vehicle with an onboard power plant. What you really want is rapid charge/discharge far more than you want storage capacity. Storing more than the equivalent of the kinetic energy required to accelerate the design weight from stationary to the design top speed does nothing for you except make the vehicle heavier than it needs to be.
If it was up to me I'd look at flywheels over capacitors long before I'd consider putting batteries in a hybrid vehicle.

2024-06-13 23:32:06 GMT

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I would be happy with a hybrid that isn't shit because automakers want to cram too much battery into them.
The ideal automobile would have electric motors for their torque curves and regenerative braking, a power plant sized for steady state operation at the design top speed (no consideration for acceleration), and a capacitor bank just large enough to accelerate the GVWR to highway speed once.
Any more electrical storage that that is just a waste of space and weight and if your power plant doesn't need to accommodate acceleration it can be a lot more efficient all while enjoying the performance characteristics of electric drive.