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Discussion Starter #1
Looking to see what the dc dc converter and 12v battery can handle. Im looking at replacing belt driven water pump in favor of a pierburg brushless water pump. They come in variety of sizes and are standard now on many high end luxury cars. Most modern hybrids and even non hybrids going to electrical water pumps so i see the effort worth it. This would put extra load on the 12v system. Already doing a lifpo4 battery with 22ah equivalent.

Now to the fun stuff. Anyone who lives in fl or hot climates knows ac is a must and drivability and mpg suffer. In ac economy i can feel it surge when ac clutch turns on and off. Its terrible. And such a drag on the engine even with my lto conversion and assist its a dog with the ac load. And for last part nothing like sitting at a light in auto stop with no ac.
So that brings up the prius ac compressor or a diy brushless outrunner motor running stock compressor which i am currently working on.

The prius compressor is 200v 3 pole salient ipm. Draws about 10-15a. But needs a controller.

Now most will say dont have pack for that yada yada yada. Heard it all before. All the negatives but jot one positive or anyone al least trying.
I have the voltage and the pack for it so im going to try. Currently i have lto conversion with a diy home made bcm fooler board im 72s right now and about 169vdc pack voltage. And planning on adding 12 more cells dor 201-218vdc in 84s configuration.
Right now with no current hack or ima hacks i cant deplete the pack. With that said i can afford to run something else from the pack.

My options for driving the compressor are an existing vfd and input my power into the dc bus. Use an arduino as micro controller to aid in controlling the ac. Or just a simple potentiometer to controll rpm.
Other option is to use the prius ac compressor inverter that is a seperate piece of the main inverter assembly but is also integrated onto the board with the dc dc converter. Just have to figure out pin outs and what signals needs to turn on.
This is out of my league as i dont know how to get can signals or code and dont have prius to try with.
And prius forum is no help as not as well organized or thdy dont mod them like people do on their insights.

Just looking for positive replies and anny info would be greatly appreciated.

Last thing would one connect this to the relay board after the battery current sensor, connect to the side of fuse for dc dc converter or same lugs as dcdc converter, or lastly a fuse atatched to the main pack positive and negative terminals.
 

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My two cents on the aircon idea.

Well as you have the 200v battery capability and spare Ah capacity you might as well use it.

You negative lead can be connected to the negative on top of the battery board.

If you connect your positive anywhere other than directly to the battery positive (before the current sensors)
then your additional load will be detected, and cause an imbalance in the amps sensed by the various current sensors,
and it will trigger an IMA fault.

So i'm saying your extra HV load must be connected so as not to be sensed by the OEM current sensors..

It will need to be correctly and independently fused (say 20A 250V dc rated fuse)
and have an independent ignition/aircon signal controlled DC HV contactor for your aircon motor driver.

Get yourself a spare battery switch board and you will have suitable HV contactor and fuse (The dc-dc one).

Actually driving your aircon motor is another matter, but a pwm 3 phase modest capability driver should be fairly easily available..

As always please post pictures and full details of your project.. Thanks
 

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I have no technical expertise, but drove a Prius C for a couple years. It was a great little car and I've seriously considered going back to one when something goes haywire with me or my Insight.

One of the things I loved about the car was its electrically-drive AC. Mileage took a hit due to recharge, sure, but running the AC without it stealing/pulsing the car's engine performance was wonderful.

In the G1, if I'm pulling out in traffic, I have to be sure the AC is OFF. With the C, there was never any problem. Of course, I could always run without the AC, but the h3ll with that. I've grown old enough to deserve not to sweat!
 

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Unless you grid-charge your battery instead of letting the car charge it, than all energy expended by the car still comes from gasoline, so it's not going to be more efficient or net you more MPG.

The water pump is a mechanical system that needs to be spun. The normal setup is, of course, engine -> belt -> water pump. To power one electrically, you need to go engine -> generator (IMA motor) -> AC-to-DC conversion (MDM) -> battery -> motor -> water pump. This incurs much, much more mechanical and electrical losses and uses more energy for the same amount of actual fluid moved.

Since the stock water pump is only running when the engine is running (as it always needs to be), I'm not sure what advantage an electric one would offer.

Same deal with the A/C compressor, though it would give you the advantage of still having A/C at a stop light and not having a fluctuating drag on the engine (it will still cause drag to run it all the time, but it won't be pulsing on and off, at least).
However, like before, all the electricity you're using to power that electric compressor still came from the gas you put in your tank. With all the energy conversion steps, you'd still likely use less fuel to just run the engine at the stop light instead of going into auto-stop.
Not to mention the electrical challenges involved in running a compressor like that with the Insight's electrical system, which I can get into if you'd like.

I'm not trying to dissuade you from trying something new, but if your goal is to use less fuel overall, it's just not gonna work out.
 

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Discussion Starter #5
Really good advise on the oem relay board for contactor and fuses.

As for the driver i was hoping to use oem honda igbt's at first with a controller. But i dont know enough about it to know where to start. Aparently hch igbt module with igbt driver circuit hooked to arduino is doable.

Then was the prius ac inverter, again dont know how to get signals to turn it on.

Most likely going to use a vfd and input on the dc bus.

Other option is the newer compressors with built in inverter but again dont know the can inputs to do anything with. Denso reply is can signals proprietary to toyota.

Thanks for info and appreciate the positive info on topic.
 

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Discussion Starter #6
Certainly not a fuel conserving modification. Just hoping for little better drivability and better systems in the car. Figure nee things are available than were available when the insight was made. Newer cars are moving bn in this direction. If worth a manufacturer to spend however much money and r&d to implement then its worth it.

I do plan to grid charge once i start doing more modifications. I do understand and know taking belt drive and switching load to electrical system transfers power elsewhere.

And having ac at a stop is primarily the reason. And electric water pump also removes load off the engine, no belt, no tensioner, no thermostat. With electric water pump can not run during start up and engine reach temp faster. Its variable speed so not always the same load. Previously in a high hp honda engine made a dyno proven 3 hp by eliminating the water pump. I know wont directly apply to the insight but anything counts. And like i mentioned before new honda hybrids have an electric water pump so its worth a shot.

And i love to tinker and cant leave things alone. If improvement can be made im going to try to do it.
 

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