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Good discussion. I was going to mention the same thing about the duty cycle control option. There are specialized drivers that do just that but of course no reason why an MCU can't do it. I was going to try it with my controller design. The idea is to limit the current with very low duty and...

The regen will work simply because body diodes in mosfets are conducting in reverse regardless whether the mosfets are on or off. This is kind of downside compared to a contactor that turns off the current flow in both directions. Most BMSes use mosfets in series to deal with that issue but of...

You can certainly play around issues by tuning values and it can work for a particular situation. The sensorless transition issue can be mitigated by pushing the switchover eRPMs higher when the power demand during acceleration tapers out the switchover is not as dramatic. It may work good...

This is typical for most hardware running vesc - I brought this up back in 2020 (Sensorless Transition and Deadtime Distortion | VESC Project) and there has been a lot of discussion about it in other threads. There are a few theories on why this is happening but my personal finding is that it's...

This is the design adopted for the PV-nextGen controllers, three 210A 150v rated mosfets are used for the contactor/pre-charge, and they are mounted on the power stage IMS board sharing the heatsink with the phase switches. The zener closest to the mosfet is a TVS to protect it from the voltage...

I've been using a modified version of the design with the added auxiliary turn-off circuit, TVS, and the capacitor from gate to source rather than the drain. It has worked fine overall even above 100v. One minor issue is that mosfets in the off state prevent the current flow from the battery to...

Going out tomorrow. Please PM for personal comm.

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yes, after-sale support can be daunting but there are some measures you can take to minimize it: - good and simple documentation, quick-start guides - pre-configured presets (mostly implemented in software/firmware) simplifying setup - remote logging to quickly pinpoint and resolve the issue...

On its way! Comes with built in pre-charge now, so it was worth the wait!

Reading this, I felt like reliving my past experience a few years back. Building a prototype and building a product are two different levels of effort and investment in terms of sweat, blood, tears, time, and money. Kudos you recognized that early.

Depends on the mosfet threshold used but simulation shows this with 2v threshold and 10uf +1M RC filter, at 100v. About 3 sec. Red is the gate, yellow is current and green is voltage. Using a thermistor sounds like throwing yet another variable. I don't see where it would add value in this case...

Just an update. TVS on the gate is a must to cover all possible scenarios such plugging in battery when the switch is on. That can cause spikes under some circumstances as shown above. Zeners are not able to handle transients. I've used the delayed gate charge approach at this time (as opposed...

A quick update: NextGen controllers now have built-in pre-charge and hi-voltage connect/disconnect features for additional safety. Based on modified version of Fechter inrush control circuit discussed here: https://endless-sphere.com/sphere/threads/active-pre-charge-inrush-control.40142/page-31