Power Match not achiving target power

Hello all

TL:DR
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When using power match, does your trainer fail to achieve target power?
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I have raised a ticket for this, but want to see if its a problem that is experienced by anyone else as the support team is confused too.
Set up:

  • Tacx Vortex on latest firmware
  • Watteam PowerBeat left side PM
  • Win 10 running TR
  • Ant+ device connections

I am using power match, riding in various gear combos to see if wheel speed is the issue but the problems remain. These are them…

When riding below 200w, power match works great. However once I start over unders, the power never reaches the prescribed target. The ‘under’ is slightly off, but the ‘overs’ are never on target. Say its 216w target for the ‘over’, the PM only registers 205.
If I increase the intensity of the workout, so the ‘over’ target is at 280w, the PM will only register 260w. Same case with VO2 efforts. This is with power match enabled. In resistance mode, no issue as I can just pedal more!

I have used PID loops, so understand what should be going on. If the PM is registering 205w, TR should be instructing the trainer to increase the resistance until PM matches the set point (target power).
I know the trainer can achieve the power because it does when I increase intensity.


This is an Over Under interval. At the start power rises nicely, then drops off, takes 45 secs to stabilise. First ‘Over’, the power does not meet target. Second ‘Over’ barely makes it. I raised the last ‘over’ by increasing the intensity. Trainer didn’t respond! Last messy part was in resistance mode to see if trainer can go higher.


Even looking at the yellow power trace, it fluctuates above and below the target line on the Unders. On the overs, it barely makes it above the target.

isnt the vortex a wheel on? I used to have this problem especially on V02max when it was 120%. with that trainer.

Easiest solution, use resistance mode. Shift for unders and keep the resistance set to hit the OVERS.

I use a Vortex with Assioma pedals using powermatch. The graph looks normal to me. Have you checked the workout summary to see if you actually made the power target for the interval rather than looking just at the graph? The Vortex is not a Kickr so you may need to use your gears more than you would with a high end trainer.

I like this version of powermatch better as it seems to drag me less into the spiral of death. That seems to do with it giving me more lee-way above/below target. It can hover below target for a bit though (I think it did for 10s last night) so I usually toggle ERG of to get back above it.

Not saying that this is the issue for you but I did have similar issues at one point with my vortex and it turned out to be poor ant+ signal.

The trainer literally did not receive the instruction to change power - nightmare when doing vo2 max intervals and the resistance getting stuck on!!!

I’d suggest a usb extension to let you place the ant dongle right next to the trainer or try Bluetooth instead.

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I had a long running troubleshoot with support on this (Win10 + PM). Try connecting with BLE and try again. One day my previously perfect (powered) ant+ connection just stopped working with TR on Win10. Still works fine on other devices and other apps, but TR Win10 and ANT+ was suddenly a no no :man_shrugging:t3:

I had a similar problem with a TACX and my Assioma pedals. switched from blutooh to ant+ and it fixed the problem.

Just to add to this. I had 30/30s yesterday in which the graph looked like this:

image

When you look at the interval summary. You can see that I pretty much hit the workout targets every time:

Definitely below target for all the overs unfortunately

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Thanks, I’ll try and toggle Erg on the next ride

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Hi
I’d be happy if my power trace looked like that. See how yours is above the line more than below it? Well, pretty much equal as your AVG matches the target.

My power trace is always below the target line.

I’ve always used a USB extension and the ant+ dongle is right below my BB.
I’ll switch to BLE and see what happens.
I can use resistance mode, but why if we have power match. I can understand for very quick VO2 intervals where the trainer cannot respond quick enough, but for a sustained effort, it should sort it self out.

It’s as though the proportional gain of the PID loop is set incorrectly. Too low. Are different power match settings applied to different trainers?

I looked back at all my rides where the issue has occured. It takes about 60s for the power to match target when doing the overs. But theare often only 60s long! So that’s why for sustained efforts I’m not noticing the issue.

Well, bit of luck on this morning’s over unders. I changed two things at onces, not great, I know! After advice from here, I switched the trainer to BLE, and also fiddled with the sensitivity on PowerMatch. Went from 0.5 to 0.6. Found the power settled at the target quicker. So now my power is much more on target for the overs. I am happy. Although they are now as hard as they used to be when I was on a dumb trainer!

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