Jake Anderson wrote:
> Bob Blick wrote:
>> KPL wrote:
>>   
>>>>> When driving, accelerate quickly and then coast.
>>>>>         
>>>> I actually practiced coasting today just to see what it's like. It's an
>>>> interesting experience.
>>>>       
>>> Does this requirement still applies to series-wound motor? Doesn't
>>> it's current naturally drop low when it does not have to accelerate?
>>>
>>>     
>> Low is not zero. Zero current is better.
>>   
> but presumably it takes more energy to get up to speed.
> IE you will pull lots of power accelerating to a higher speed (with more 
> aero losses) then decelerate at 0 power, then pull lots of power again 
> to maintain a speed.
> You would be best off accelerating at the peak efficiency of the motor. 
> Then perhaps optimize the motor selection to have an efficient cruse 
> speed. Your batteries etc will provide much more energy at lower current 
> draw to boot. Especially with lead acids.

What I'm saying is that looking at the different places where loss
occurs, and discharge characteristics of batteries, it's hard to say
what driving style will work best. I could use the same data as you are
drawing from and make the opposite argument. For instance, lead-acid
batteries like to have recovery time. My method gives them that time,
yours doesn't. How important is that? The data available from the
manufacturers isn't going to give you anything you can calculate from.

But when it comes to talking about practical experience, I can say
without a doubt, accelerating quickly and then coasting is the most
efficient method for electric cars. It's also the method that works best
for a Honda Insight hybrid. I can't speak about other hybrids.

Cheerful regards,

Bob


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