// #eevblog — 2026-06-16
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00:09:42 <Kuschelpony> would be easier if i would had used them ever
00:55:33 Join: steve30 ([email protected]) to #EEVblog
00:55:35 Mode: (by ChanOP) +o steve30
01:07:23 <MrMobodies> Steve30, what milk do you like with your coffee?
01:07:42 <steve30> whole
01:08:14 <MrMobodies> how about the ones in the glass bottles that haven't been pasterized?
01:08:33 <MrMobodies> I found one in Waitrose I found them the best
01:09:26 <MrMobodies> this was it
01:09:47 <MrMobodies> https://www.waitrose.com/ecom/products/the-estate-dairy-unhomogenised-organic-whole-milk/762999-1-2
01:10:18 <MrMobodies> really complements the cofee
01:20:10 <steve30> its fine if you shake it up
02:42:31 Join: blastsnoop104892acb ([email protected]) to #EEVblog
02:44:11 <blastsnoop104892acb> any EE's on here? there's a public spat between two company EE's which could do with further thoughts. https://www.reddit.com/r/bikewrench/comments/1rkw96c/son_ladelux_dynamo_hub_drag/
02:45:30 <blastsnoop104892acb> It's a German and UK company that make high-end bicycle/usb charging products for dynamo hubs (for bicycles). Lots of heat on charging small li-ions at 2C, reactance and others
02:50:44 <blastsnoop104892acb> high-end light/usb charging products
02:57:23 <Kuschelpony> whats your question??
03:10:46 <rc_garage> he asked if there are any EE's here
03:11:21 <blastsnoop104892acb> not so much a question it's to correlate what's being said on the thread
03:12:42 <blastsnoop104892acb> there are a number of points raised such as whether charging a 1200mA small lithium at 2C is acceptable. Whether correcting inductive reactance without capacitance is possible.
03:13:51 <blastsnoop104892acb> supplying 1A current limit to a USB using BC 1.2 profile (1.5A) and whether the EE is right to suggest a UVLO is needed
03:15:18 <blastsnoop104892acb> the overvoltage handling of one product, whether its a good idea or not
03:19:37 <Kuschelpony> i can comment at least about the reactance thing:
03:19:59 <blastsnoop104892acb> if you know your stuff please do
03:20:26 <Kuschelpony> a capacitor is the most simple thing but can tune the alternator inductivity only at a specific rotation speed, below this speed the power output drops entirely instead of gradually
03:21:35 <Kuschelpony> it woud be possible to engineer an circuit (based on an Class-D amplifier) that presents itself as a negative inductivity that compensates the positive inductivity of the alternator at any speed, and at the same time works as active rectifier
03:22:57 <Kuschelpony> maybe someone who loves tinkering and overengineering has already done this, but i strongly suspect that it gives any meaningful gain over a simple passive rectifier plus maximum power point tracking circuit (easier)
03:23:48 <Kuschelpony> also i thinkpeople will dislike it when the bike draws considerably more than 3W from their pedaing power at higher speed
03:23:50 <blastsnoop104892acb> wouldn't it need an inductor roughly the equivalent size, modulated by the PWM?
03:25:35 <Kuschelpony> no, the inductor could bemuch smaller, lookat the 5*10*10mm cubes on (true) 50W TPA3118 boards, this one inductor only needs to deal with the switching frequency of the Class-D chip but the energy storage for the virtual negative inductivity is the capacitor smoothing the DC bus anyway
03:28:02 <blastsnoop104892acb> what's the theory behind how it works? If an inductor and frequency produce a positive reactance how do you get back to zero phase?
03:29:33 <blastsnoop104892acb> and how would that work with active rectification, one isolated and inverted?
03:31:09 <Kuschelpony> letssee it as a series circuit
03:31:35 <Kuschelpony> there is the EMF inside the alternator and its inductivity in series
03:32:34 <Kuschelpony> the inductivity obviously chokes the current (side comment, this is exactly what makes the classic light bulb system workable at all)
03:33:11 <blastsnoop104892acb> yep get that
03:33:47 <Kuschelpony> now the electronics senses the current that flows and feeds back an voltage that is 90° shiftet relative to this current
03:34:23 <Kuschelpony> this appears as a negative inductivity or a capacity that is magically matching resonance at any speed
03:35:05 <Kuschelpony> because with 90° phase shift the electronics delivers purely reactive power and therefore zero average DC side current
03:35:38 <Kuschelpony> in this case, current would only be limited by the resistance of the alternator wire
03:37:19 <blastsnoop104892acb> I undersatand the theory but not the practical implementation. If the phase is shifting (frequency is changing) how would it know how much negative inductive equiv to produce?
03:40:52 <blastsnoop104892acb> I've been trying to find an example circuit or chip that can do it but so far unable
03:41:34 <Kuschelpony> outside loop is a regulator for the voltage of the DC bus or the tapped off current to charge battery, this is injected as phase shift set point into a inner loop with an PLL controlling an oscilator
03:42:37 <Kuschelpony> mmh i think we can draw up easily an example circuit, but i strongly doubt there is any readymade chip, because as i mentioned above a much simpler approach would give almost the same performance
03:43:02 <blastsnoop104892acb> simpler being capacitors?
03:43:34 <blastsnoop104892acb> but bike speed changes so the frequency is volatile. Here it may have an advantage
03:44:49 <Kuschelpony> simpler as in no tuning at all, just rectifying and running an maximum power point tracker (well known from photovoltaics) to extract the most power from the simple rectifier
03:45:37 <blastsnoop104892acb> simpler but less power, 25-30% less
03:46:22 <Kuschelpony> beyond something 10km/h a bike alternator is a constant current source and you can raise the voltage and therefore extracted power practicaly linearly with speed
03:46:56 <Kuschelpony> btw: if it has no clamping diodes, you can reach beyond 50V at 40 to 50km/h
03:47:03 <blastsnoop104892acb> yep but power factor displacement is still a limitation
03:47:14 <Kuschelpony> right, i do not disagree
03:48:12 <blastsnoop104892acb> I've been scouring google and I can not find a single example of negative impedance with active rectification
03:48:24 <blastsnoop104892acb> not saying it doesn't exist, wondering if I'm searching correctly
03:48:36 <Kuschelpony> active rectification is just a by-product of the class-D amplifier
03:48:50 <Kuschelpony> like a variable frequency drive in regeneration
03:49:51 <Kuschelpony> we are talking about something like a (synchronous machine) variable frequency drive set to maximum regeneration
03:52:17 <blastsnoop104892acb> If it's possible to make a scrap block diagram or something that would be awesome, it's new to me
03:53:11 <Kuschelpony> im happy to do tomorrow (its getting closer to bedtime here)
03:53:34 <Kuschelpony> maybe someone else in the chat has further ideas to explain
03:53:36 <blastsnoop104892acb> very cool, I'll come back on
03:56:34 <blastsnoop104892acb> can you see anything on google which is close?
03:57:24 <Kuschelpony> oh i dont use google, but might do some duckduckgo searches tomorrow
03:57:48 <Kuschelpony> (sorry dont want to kill this conversation but i should be on the train at 5 tomorrow)
04:00:58 <blastsnoop104892acb> no thanks for your help
04:01:07 <blastsnoop104892acb> much appreciated love learning
04:02:06 <Kuschelpony> thats one of the reasons we have the chat here
04:02:32 <Kuschelpony> and sorry that we ive on different continents with different timezones, goodnight
04:02:40 <blastsnoop104892acb> goodnight
04:02:42 Quit: Kuschelpony ([email protected]) Quit: Ex-Chat
05:04:12 Quit: blastsnoop104892acb ([email protected]) Ping timeout: 2 minutes
11:00:38 Quit: DogWomble ([email protected]) Connection closed
11:11:39 Join: DogWomble ([email protected]) to #EEVblog
13:33:28 <MrMobodies> Well that is nice
13:33:29 <MrMobodies> https://news.sky.com/story/trumps-iran-war-is-one-of-the-greatest-strategic-blunders-in-us-history-13554425
13:33:30 <EEVBot> [url] Access Denied | news.sky.com
13:33:44 <MrMobodies> I hope the energy prices can now start falling instead of going up.
13:34:22 <MrMobodies> "After a war that has cost an estimated $30bn, killed thousands and destroyed hundreds of millions of dollars worth of US military hardware"
13:34:42 <MrMobodies> I didn't know it could run up that much in what appears to me a short while.
13:36:17 <MrMobodies> one step to avoiding a world war 3
13:40:44 <MrMobodies> https://www.pulsetoday.co.uk/news/special-investigations/making-complaints-work/patients-using-ai-to-send-legal-letters-to-gp-practices-says-indemnity-provider/
13:40:46 <EEVBot> [url] Patients using AI to send legal letters to GP practices, says indemnity provider - Pulse Today | www.pulsetoday.co.uk
13:41:23 <MrMobodies> Please to see them getting a taste of their own medicine. Talking of the ones that switched to an AI chatbot ONLY...
16:06:44 Quit: ibiza ([email protected]) austnet.org!NickOP (Kill requested by neo)
16:06:50 Join: ibiza ([email protected]) to #EEVblog
16:50:22 Quit: blacklotus89 ([email protected]) Ping timeout: 2 minutes
16:50:29 Join: blacklotus89 ([email protected]) to #EEVblog
17:01:40 Join: blastsnoop104892acb ([email protected]) to #EEVblog
17:37:46 Quit: steve30 ([email protected]) Quit: <Baljem> steve30: by the way, I had the most bizarre dream the other day that someone came in here and seriously flipped their shit over your quit message and why aren't the ops /doing/ something about it
18:53:14 <blastsnoop104892acb> Hallo, waitinf ro Kuschelpony to come back on. I was discussing with him about phase correction in an inductive circuit using negative impedance rather than capacitance. Anyone came across it before?
19:05:03 <Ysjoelfir> Mr. Schmusepferdchen will be back soon I guess, he's here daily, usually. And, he's a cool guy.
20:40:57 <electrohead> !coffee
20:40:58 * EEVBot pours coffee down electrohead's throat
20:42:40 <DogWomble> !coffee electrohead with a side serving of being slapped about a bit with a rainbow trout with Monty Python's Life Of Brian playing in the background
20:42:40 * EEVBot slides a cup of joe to electrohead with a side serving of being slapped about a bit with a rainbow trout with Monty Python's Life Of Brian playing in the background
20:44:12 <electrohead> lol
20:45:11 * DogWomble stickso n an episode of invader zim
20:46:17 <electrohead> Think I found a mole in the chat
20:46:22 Kick: ibiza was kicked by electrohead (electrohead)
20:50:24 <electrohead> > Kill requested by neo
20:50:33 <electrohead> That's the part that stands out like a sore thumb
20:50:35 <electrohead> heh
22:06:18 * Ysjoelfir starts digging to find more moles
23:18:25 Quit: krish2487 ([email protected]) Ping timeout: 2 minutes
23:18:29 <electrohead> I'm just curious if said person rejoins and etc
23:18:45 <electrohead> Anywho, happy tuesday and things!
23:19:22 <electrohead> !caffeine Ysjoelfir
23:19:22 * EEVBot forces caffeine into Ysjoelfir
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