MGU-H/MGU-K/energy store mix

[Tommy Cookers]

..... But I suspect that there are legal traction control benefits to using as much MGU-K as possible when traction limited. Then when wheel-spin occurs, the natural operation of an electric motor to increased rpm automatically reduces its torque output to help stop the wheel-spin.

agreed !
this I have said for years
but the MGs will have an inherent anti-spin benefit greater than you suggest
(and even with 'old-technology' eg brushed MGs a natural control regime is implausible on practical grounds)

brushless or synchronous machines have inherently what amounts to speed control
the software will be sweeping the motor excitation upwards during acceleration (additional to whatever current control regime)
wheelspin is strongly opposed as the motor torque collapses as the excitation voltage 'lead' over the back EMF collapses (on spin)
the likely system would inherently have motor torque tending to reverse at spin onset, giving greater anti-spin effect
this is just the plain normal 2 quadrant system characteristic

the rules limiting MG torque are the only thing that limits this anti-spin effect
(it's legal because it does not breach the 'traction control' rules)

[bergie88]

The combination of power from the ICE and the MGU-K is very interesting in terms of traction control. Does anyone know how the rules on traction control are defined exactly? There is a possibility to deliver an amount of power from the ICE which could always be handled by the wheels, with an added amount of power from the MGU-K with a control loop on the traction of the wheels to get the maximum possible power at the wheels.

[gruntguru]

That would be illegal.