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US 12,015,621 B2Granted
Apparatus and method for estimating system state
AssigneeDaegu Gyeongbuk Institute of Science and Technology
InventorsYechan Jeong, Yongsoon Eun
Life of this patent
Estimating the term…
Abstract
Disclosed are an apparatus and a method for estimating a system state. Accordingly, it is possible to perform Resilient State Estimation (RSE) that is robust to disturbance and is autonomously restored from sensor attack/failure.
Claims15
An apparatus for estimating a system state, the apparatus comprising:
- at least one processor configured to:
- generate a plurality of partial state estimation values ({circumflex over (z)}1,{circumflex over (z)}2, . . . {circumflex over (z)}p;
- {circumflex over (z)}i) for a current state of a target system, based on a control input for the target system and output values (y1, y2, . . . , yp;
- yi) of a plurality of sensors disposed in the target system corresponding to state observation values of the target system according to the control input;
- determine a set (Γ({circumflex over (z)}(t)) of a plurality of candidate estimation values (X(t)) for a total state estimation value of the target system, based on the plurality of partial state estimation values;
- and
- determine a final state estimation value ({circumflex over (x)}(t) for the current state of the target system among the plurality of candidate estimation values (X(t)),
- wherein, in order to generate the observer state (gi) and the plurality of partial state estimation values ({circumflex over (z)}1,{circumflex over (z)}2, . . . {circumflex over (z)}p;
- {circumflex over (z)}i), the at least one processor is configured to perform:
- a first calculation of generating a first observability matrix (Ai1) and a second observability matrix (G), based on a property matrix (A) of the dynamic state equation and an output matrix (C) for the plurality of sensors,
- a second calculation of generating a first linear transformation matrix (Mi), based on a range space (P) of a transpose matrix (GT) of the second observability matrix (G) and orthogonal bases (Q) of a null space of the second observability matrix (G),
- a third calculation of generating a second linear transformation matrix (MiAi1MiT) by performing a coordinate change for the first observability matrix (Ai1) through the first linear transformation matrix (Mi),
- a fourth calculation of generating a fourth linear transformation matrix (Ni′AiōNi′−1) by performing a coordinate change for a matrix block Aiō through a third linear transformation matrix Ni′ making the matrix block Aiō of the second linear transformation matrix (MiAi1MiT) to be block diagonal,
- a fifth calculation of generating a sixth linear transformation matrix (Ti), based on a fifth linear transformation matrix (Ni) defined based on the third linear transformation matrix and, the first linear transformation matrix (Mi),
- a sixth calculation of generating a seventh linear transformation matrix (Ui) and an eighth linear transformation matrix (Vi), based on the sixth linear transformation matrix (Ti) and an inverse matrix (Ti−1) of the sixth linear transformation matrix (Ti), and
- a seventh calculation of transforming the dynamic state equation, based on the seventh linear transformation matrix (Ui) and the eighth linear transformation matrix (Vi).
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A method of estimating a system state performed by at least one processor of the apparatus for estimating the system state, the method comprising:
- generating a plurality of partial state estimation values ({circumflex over (z)}1,{circumflex over (z)}2, . . . {circumflex over (z)}p;
- {circumflex over (z)}i) for a current state of a target system, based on a control input for the target system and output values (y1, y2, . . . , yp;
- yi) of a plurality of sensors disposed in the target system corresponding to state observation values of the target system according to the control input;
- determining a set (Γ({circumflex over (z)}(t))) of a plurality of candidate estimation values (x(t)) for a total state estimation value of the target system, based on the plurality of partial state estimation values ({circumflex over (z)}1,{circumflex over (z)}2, . . . {circumflex over (z)}p;
- {circumflex over (z)}i);
- and
- determining a final state estimation value ({circumflex over (x)}(t)) for the current state of the target system among the plurality of candidate estimation values (X(t)),
- wherein the inducing of the observer states (gi) comprises a first calculation operation of generating a first observability matrix (Ai1) and a second observability matrix (G), based on a property matrix (A) of the dynamic state equation and an output matrix (C) for the plurality of sensors, a second calculation of generating a first linear transformation matrix (Mi), based on a range space (P) of a transpose matrix (GT) of the second observability matrix (G) and orthogonal bases (Q) of a null space of the second observability matrix (G), a third calculation of generating a second linear transformation matrix (MiAi1MiT) by performing a coordinate change for the first observability matrix (Ai1) through the first linear transformation matrix (Mi), a fourth calculation of generating a fourth linear transformation matrix (Ni′AiōNi′−1 by performing a coordinate change for a matrix block Aiō through a third linear transformation matrix (Ni′) making the matrix block Aiō of the second linear transformation matrix (MiAi1MiT) to be block diagonal, a fifth calculation of generating a sixth linear transformation matrix (Ti), based on a fifth linear transformation matrix (Ni) defined based on the third linear transformation matrix and, the first linear transformation matrix (Mi), a sixth calculation of generating a seventh linear transformation matrix (Ui) and an eighth linear transformation matrix (Vi), based on the sixth linear transformation matrix (Ti) and an inverse matrix (Ti−1) of the sixth linear transformation matrix (Ti), and a seventh calculation of transforming the dynamic state equation, based on the seventh linear transformation matrix (Ui) and the eighth linear transformation matrix (Vi).
5 more elements
Dependencies are inferred from the claim text.