I'm trying to better understand what actually happens to a motor when a VFD is decelerating it. And how it would act if physically stopped while still in the decel process.
If I had a fly wheel spinning, and set the VFD to coast to stop, the fly wheel would just spin, slowly losing speed until it stops. Something like an external brake could stop the fly wheel just working against the inertia of the flywheel.
But what if you are applying an external brake to a flywheel that is still in an active decel ramp? If it is a decel that is longer than what the brake would take to stop the load, would the VFD's deceleration ramp be working against the braking action? If the brake could stop the wheel in 20 seconds, but your VFD had a 60 second deceleration.
These are just hypothetical situations, no real world numbers. I don't have a fly wheel with a VFD and a brake. I'm just trying to think of an actively decelerating vs coasting load both having an external brake applied. Or any other sort of action that would be counter to the spinning motor's load during that time.
If I had a fly wheel spinning, and set the VFD to coast to stop, the fly wheel would just spin, slowly losing speed until it stops. Something like an external brake could stop the fly wheel just working against the inertia of the flywheel.
But what if you are applying an external brake to a flywheel that is still in an active decel ramp? If it is a decel that is longer than what the brake would take to stop the load, would the VFD's deceleration ramp be working against the braking action? If the brake could stop the wheel in 20 seconds, but your VFD had a 60 second deceleration.
These are just hypothetical situations, no real world numbers. I don't have a fly wheel with a VFD and a brake. I'm just trying to think of an actively decelerating vs coasting load both having an external brake applied. Or any other sort of action that would be counter to the spinning motor's load during that time.
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