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Many people have asked if the Insight or Civic can be run without the IMA.
The answer is yes, but the 12V battery is not being charged, since the IMA must be operational to charge the IMA battery, so it can power the DC/DC converter, to maintain the 12 volt system .
Ways around it?
Use a large deep cycle 12V battery instead of the tiny one. This would give 6-10 hours of driving, with the lights on, and could be recharged each nite. A plug in hybrid for a different reason

Mount an alternator on the car?
Difficult, not much room. The AC area would be easies, but I like AC. A major mechanical project.

We know from our hybrid training classes that the IMA motor is always generating ac voltage, and can output 50 or more Amps at up to 250V at high rpm. This is with the IMA out of the car, totally disconnected.

A simple 220V 60hz transformer with a 24V secondary, connected across any two legs of the motor terminals, would give isolated 0-35V output to power a 12V charging system with voltage regulator. That would allow the complete removal of the IMA electronics and HV batteries, with only a lb or two of charger weight added back.
Should work. Anyone with a dead battery that wants to try it, let me know.;)

Hi Mike.

Good suggestion with the step down approach to charging the 12V battery. I'm going to give this approach a more careful look just to see how it would apply to the HCH-2. I'll drip some thoughts of my own into this process and any consequences... it's well worth a look.

Cheers;

MSantos

OK, I had a quick look at the HCH-2 schematics and this is what I came up with:

The HCH-2 IMA motor is a high density three phase unit (U,V,W). The cables go straight to a high power transistor bridge which then feeds the voltage converter module and the AC compressor Driver.

Concerns:

-A simple passive step down transformer may not be appropriate. I see a properly designed cooperative circuit having a chance to behave more like a safe plugin since any kind of feedback to the phase sensors will probably generate any combination of downstream codes and throw the MBM off-line.
-It is a three phase unit. From your earlier post should I assume that prior IMA's were a two phase implementation?

Perhaps you did not emply that such a mod would be applicable to the 4gen IMA in the HCH-II?

Cheers;

MSantos

I was not suggesting that this was to be used in a car with the IMA turned on, as there is no need. This was to give people that are faced with a battery pack replacement, and feel that they could live with the car without the IMA.
The Idea was to use the isolated stepdown transformer, rectify the output, and build a simple voltage regulator to control the DC output so the 12V system is charged with sufficient current to maintain charge when driving at night. a 10-15A current should be sufficient. The three phase output of the IMA Motor/Generator is present without the 3 phase bridge driver, or any of the IMA electronics.
The unbalanced load on one of the phase windings will not be an issue if the IMA is turned off, or out of the car as suggested. I suspect that even with the IMA functioning, we could rob 1-2 amps from one phase without the system setting codes, but that is only speculation.
As I said, we have powered two 1500W shop lights from a HCH-2 IMA motor while the complete IMA box was completely out of the car. We blew one bulb out when the engine was reved too high.;)

Mike, thank you for clarifying it for me.

Under those circumstances it would work very well indeed.

It is a pitty that finding these cars written off for parts is not that easy. We have put word on most of the wreck/parts yards for a heads-up when such a vehicle comes in so that we can get our hands on some of this hardware.

Darn HCH-2 drivers !!! Why can't they be a little more reckeless when driving ??? ;)

Cheers;

MSantos

Just did a quick check of the Copart auctions. There are currently 13
HCH 2004-2007 up for auction in the next couple of weeks.

Darn HCH-2 drivers !!! Why can't they be a little more reckeless when driving ??? ;)


But then I'd screw up my mileage :D