Power Consumption

You need to be far more specific in your questions. The ones you have posted are not single valued.

Tom

 

The spec states that the maximum power the 2004-2009 Prius can provide for acceleration is 82 kW (110 HP). This is less than the sum of the engine and battery system powers because it can't use all of both at once. The maximum regeneration power is not stated; estimating very roughly from the Consumption display it looks to be a few kW.

Why do you ask?

 

As for acceleration, it varies depending on how heavy you push on the accelerator pedal... I believe it takes approx 20 amps to start the engine.

As for regeneration, with the foot off the brakes, it can regenerate between 1.1amps to approx 20 amps.

When brakes are used it can regenerate between 1.1amps to over 90amps (in ideal conditions).

 

How about being specific with your question. Power consumption doing what?

Tom

 

I'm going to give you my rough guestimate:

- The 12V bus load with all accessories on including rear window defroster and PTC electric cabin heaters is probably going to be around 70A, so you will need around 1 kW of power given 13.8V on the 12V bus.

- The traction battery is rated at 28 hp or 21 kW. Therefore under full acceleration, you can expect the battery to deliver its full power rating for a brief time period which would require around 100A of current since the nominal battery voltage is 201.6V.

Therefore, I think you would need 22 kW of peak electric power to run the vehicle and allow full acceleration. This does not include the additional power provided by the gasoline engine.

For your purposes, I would imagine that you will plan to obtain a test vehicle so that you can make your own measurements and be more precise about this. Good luck.

 

The simple answer is "all of it."

Another answer is to take the mass of the vehicle and driver and acceleration time to some fixed speed, say 60 mph (96 kph). Use the formulas for calculating the kinetic energy at that speed and the time interval to reach that speed and calculate the power. If you'll check Google, you can find web pages at the hot rodding sites that let you put in mass and time to speed values and kicks out the vehicle power needed to reach that speed.

Since regenerative braking is handled by MG2, the maximum is ~50 kW (NHW20.) However, the traction battery has a lower power limit, ~25 kW if I remember correctly. The traction battery capacity is the limit of regenerative power capture.

This is actually something you could measure if you have access to a 'clamp on' DC amp meter. I haven't used a Scanguage but I would expect it to report traction battery and volts. But there is a third approach, differential fuel consumption:

• reset your mileage display and tripmeter
• drive around for at least half an hour, an hour is better to throughly warm up the vehicle
• park the car and record the starting miles and MPG and calculate the fuel burned
• turn on every load you want and do something else for about an hour
• go out and record the new MPG, miles haven't changed but use the new MPG to calculate the fuel burned. Subtract the first fuel burned from the second and you have how much was burned to keep everything on.
• wait another hour or so, record the new MPG
• repeat a long as possible to improve accuracy

Now using the decrease in MPG, calculate how much fuel was burned to keep all of the vehicle systems on and running. Then use 37% as the engine efficiency and the energy content of your fuel, gasoline, to calculate the load. BTW, this "load" includes the heat lost, another load that is often overlooked.

Bob Wilson

 

High School Science project ?
Ultracapacitors have captured many a fancy for quite a few years running.

 

xreBornx, are you aware of the Argonne National Labs' energy published analyses of the Prius? I think that links to them may be somewhere at priuschat.