inverter tempHS fluctuations

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FFMan
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inverter tempHS fluctuations

Post by FFMan »

I'm adding some over under range detection to my code and (assuming no bugs in my code etc) note that temphs (I have it mapped to a can message like so can tx tmphs 20 0 16 1.00 0), varies wildly and quickly.

It'll start off at approx ambient and on a light throttle will be around 50, but if i nail the throttle in rises within seconds to 90+, and the settles equally as quickly when i lift off. The fluctuations are so quick and large that it's hard to believe it is measuring temperature at all.

What is the experience of others if monitoring this ?
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Bigpie
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Re: inverter tempHS fluctuations

Post by Bigpie »

It's like this on the Prius gen3 inverter, it's measuring the temperature of the IGBTs. It will rise and fall rapidly.
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Re: inverter tempHS fluctuations

Post by FFMan »

Bigpie wrote: Mon Aug 21, 2023 9:35 am It's like this on the Prius gen3 inverter, it's measuring the temperature of the IGBTs. It will rise and fall rapidly.
ok - so normal

what might a sensible maximum value alert be do you think ?
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Re: inverter tempHS fluctuations

Post by Bigpie »

Personally, I don't worry about it :D The Prius inverter will protect itself, can't remember if it cuts out or derates, but I've never managed to get there with my setup.
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Re: inverter tempHS fluctuations

Post by bexander »

Bigpie wrote: Mon Aug 21, 2023 10:10 am Personally, I don't worry about it :D The Prius inverter will protect itself, can't remember if it cuts out or derates, but I've never managed to get there with my setup.
I use the Yaris inverter with the same behaviour and I agree with Bigpie.
FFMan wrote: Mon Aug 21, 2023 9:36 am ok - so normal

what might a sensible maximum value alert be do you think ?
I have a warning light come on at 80degC over a 10 sample average.
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Re: inverter tempHS fluctuations

Post by FFMan »

> I have a warning light come on at 80degC over a 10 sample average.

ok - mine was set to 65 over 10 average and kept alerting so i'll push it up.

thanks
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