WiP: Pfeiffer TVP-250 controller
Posted: Sun Nov 06, 2016 8:22 am
Hey everyone,
as mentioned in my introduction post (viewtopic.php?f=45&t=11007),
I am currently building a controller for my good old Pfeiffer TVP-250: The motor is a four-phase "brushless DC" type, with a permanent magnet on the shaft.
Thus, by applying a DC voltage to any of the phases with respect to the center tap, the rotor
rotates into a well-defined position. As it turns out, to accellerate the rotor, a constant phase
shift of 45 degrees has to be maintained between the driving magnetic field and the magnet on the rotor.
Yesterday evening I was able to test the new driver electronics for the first time.
The L6203 run pretty hot given that they used to be mosfets, but nothing a nice heatsink could not cope with.
Here are the EAGLE schematics again: A video of the first run is found on YT: https://youtu.be/dmyyyMA9du0
The oscillation is due to the rotor locking on the driving field, being accellerated, then the phase shift
(and thus the driving force) vanishes and the rotor deccellerates again.
Next step are:
1) Attach a Hall sensor (TLE 4905L) in the vicinity of the shaft end which has a magnet already attached.
The original drive circuit also used Hall sensors, but in an all-analog approach.
2) The bearings have to be replaced, they sound really bad.
3) The motor for the oil pump has to be brought back to working condition.
4) A cooling water supply is needed.
5) I need to turn some ISO K and KF flanges for connecting the turbo to my forepump (Alcatel 2012) and to some pressure gauge(s),
This is a work-in-progress report, so stay tuned
Cheers,
Jonathan
as mentioned in my introduction post (viewtopic.php?f=45&t=11007),
I am currently building a controller for my good old Pfeiffer TVP-250: The motor is a four-phase "brushless DC" type, with a permanent magnet on the shaft.
Thus, by applying a DC voltage to any of the phases with respect to the center tap, the rotor
rotates into a well-defined position. As it turns out, to accellerate the rotor, a constant phase
shift of 45 degrees has to be maintained between the driving magnetic field and the magnet on the rotor.
Yesterday evening I was able to test the new driver electronics for the first time.
The L6203 run pretty hot given that they used to be mosfets, but nothing a nice heatsink could not cope with.
Here are the EAGLE schematics again: A video of the first run is found on YT: https://youtu.be/dmyyyMA9du0
The oscillation is due to the rotor locking on the driving field, being accellerated, then the phase shift
(and thus the driving force) vanishes and the rotor deccellerates again.
Next step are:
1) Attach a Hall sensor (TLE 4905L) in the vicinity of the shaft end which has a magnet already attached.
The original drive circuit also used Hall sensors, but in an all-analog approach.
2) The bearings have to be replaced, they sound really bad.
3) The motor for the oil pump has to be brought back to working condition.
4) A cooling water supply is needed.
5) I need to turn some ISO K and KF flanges for connecting the turbo to my forepump (Alcatel 2012) and to some pressure gauge(s),
This is a work-in-progress report, so stay tuned
Cheers,
Jonathan