Common Mode Servo Block Diagram

Document #:

LIGO-D1002416-v5

Document type:

D - Drawings

Abstract:

Block diagrams for the common mode servo and input mode cleaner servo, as given in the schematic D040180, rev E.

Files in Document:

• CM Servo (CMServoBlockDiagramE.pdf, 105.2 kB)

Other Files:

• IMC Servo (IMC_CMServoBlockDiagramE.pdf, 104.3 kB)
• OmniGraffle source (ServoGraffleFiles.zip, 22.8 kB)

ICS/JIRA Record:

• ICS_LINK

Topics:

• Sensing and Control

Authors:

• Peter Fritschel

Keywords:

aLIGO ISC Electronics

Notes and Changes:

v3 updated for rev E of D040180:
- added sign switch to each input
- indicated that Exc B is switchable between Fast and Slow paths
- swapped the order of the compensation and boost in the slow path

v4: minor corrections to v3

v5: made an extra diagram for the imc servo, from original cm servo diagram
- generic filter replaced by comm comp 2
- high passes in fast path replaced with 'p/z = 140kHz/70kHz'
- 100kHz low pass to 2kHz low pass in slow path
Edited the original common mode servo diagram
- included the switching logic

Referenced by:

• LIGO-E1200175: aLIGO, ISC, Electronics, Common Mode Servo