Abstract

Apparatus for implementing Adjustable Compensation Ratio (ACR) active shielding or control of physical fields (magnetic, electric, electromagnetic, acoustic, etc.), comprising the addition of a secondary internal feedback loop within a conventional primary closed feedback loop topology. Compensation-ratio transfer function order and coefficients adjustment permits accommodating frequency-dependent and frequency-independent effects within a Protected Volume when a system field sensor or sensor array is not at the exact location where external field interference must be optimally canceled. A Laplace polynomial term precisely sets this parameter in a supplementary feedback link by modeling the frequency-dependent characteristic of an Interacting Medium without deleterious effect on other desirable primary closed-loop characteristics. The inventive ACR can be used in advanced active cancellation for magnetic shielding purposes.

IPC Classes  ?

• G01R 35/00 - Testing or calibrating of apparatus covered by the other groups of this subclass
• H03H 11/04 - Frequency selective two-port networks
• G01R 33/025 - Compensating stray fields
• G01R 33/00 - Arrangements or instruments for measuring magnetic variables
• G01R 33/389 - Field stabilisation
• G05B 13/04 - Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators

Abstract

Apparatus for implementing Adjustable Compensation Ratio (ACR) active shielding or control of physical fields (magnetic, electric, electromagnetic, acoustic, etc.), comprising the addition of a secondary internal feedback loop within a conventional primary closed feedback loop topology. Compensation-ratio transfer function order and coefficients adjustment permits accommodating frequency-dependent and frequency- independent effects within a Protected Volume when a system field sensor or sensor array is not at the exact location where external field interference must be optimally canceled. A Laplace polynomial term precisely sets this parameter in a supplementary feedback link by modeling the frequency-dependent characteristic of an Interacting Medium without deleterious effect on other desirable primary closed-loop characteristics. The inventive ACR can be used in advanced active cancellation for magnetic shielding purposes.

IPC Classes  ?

• G01R 33/025 - Compensating stray fields
• G01R 33/028 - Electrodynamic magnetometers