[Michimura, Komori]
We succeeded in increasing the unity gain frequency (UGF) of the 3km Michelson interferometer control from 10Hz to about 300Hz ! (micholtf.png)
By correcting the signs of the feedback signal as klog #1340, the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.
By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.
We succeeded in increasing the unity gain frequency (UGF) of the 3km Michelson interferometer control from 10Hz to about 300Hz!
By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
| before | after | |
| notch filter | on | off |
| cutoff frequency of high-pass filter for phase compensation | 7 | 70 |
| cutoff frequency of low-pass filter | 200 (secondary) | 2000 (secondary) |
| K1:LSC-MICH_GAIN | 1 | 800 |
cutoff frequency of low-pass filterWe succeeded in increasing the unity gain frequency (UGF) of the 3km Michelson interferometer control from 10Hz to about 300Hz!
By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.
We succeeded in increasing the unity gain frequency (UGF) of the 3km Michelson interferometer control from 10Hz to about 300Hz!
By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.
We succeeded in increasing the unity gain frequency (UGF) of the 3km Michelson interferometer control from 10Hz to about 300Hz!
By correcting the signs of the feedback signal as klog #1340,
the excitation of pitch mode (over 10Hz) by feedback control got smaller,
and we don’t have to insert notch filter.
It was a key point of increasing UGF.
Accordingly, the set value of MICH_LOCK guardian was changed as follows.
