Simulation Study on Application of Nonlinear Model Predictive Control to the Superfluid Helium Cryogenic Circuit*

Noga, Rafal; Ohtsuka, Toshiyuki; Prada, César de; Blanco, E.; Casas, J.

doi:10.3182/20110828-6-it-1002.02156

Cited by 3 publications

(1 citation statement)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then, a distributed-parameters model of the temperature dynamics at a 214-m long subsector of the SHCC at the LHC, having 10 states, has been used in the first version of NMPC and MHSE unsuccessfully tested at the LHC, proving that real-time feasibility may be achieved with a more complex, distributed parameters model if a tailored optimization algorithm is applied [7]. This paper presents the first ever working prototypes of MHSE and NMPC applied to the temperature stabilization in an SHCC sub-sector at the LHC.…”

Section: Introductionmentioning

confidence: 99%

Non-linear moving horizon state estimation and control for the superfluid helium cryogenic circuit at the large Hadron Collider

Noga

Prada

Ohtsuka

et al. 2014

53rd IEEE Conference on Decision and Control

Self Cite

View full text Add to dashboard Cite

We consider the problem of temperature stabilization of the Large Hadron Collider's (LHC) superconducting magnets, cooled with superfluid helium 4 (He II). The temperature dynamics is highly non-linear, exhibiting inverse response, variable dead-times, strong couplings between process variables and strong saturation effects. Multiple operational constraints must be respected. We present a prototype application of a hybrid Non-linear Moving Horizon State Estimation -Luenberger observer (MHSE-LO) and Non-linear Model Predictive Control (NMPC). It is based on: 1) a detailed, low computing cost, first principles model of the temperature dynamics and 2) a simple optimization approach tailored for systems with stiff dynamics. The prototype control system has been tested at the LHC, demonstrating excellent, robust performance.

show abstract

Section: Introductionmentioning

confidence: 99%

Non-linear moving horizon state estimation and control for the superfluid helium cryogenic circuit at the large Hadron Collider

Noga

Prada

Ohtsuka

et al. 2014

53rd IEEE Conference on Decision and Control

Self Cite

View full text Add to dashboard Cite

show abstract

NMPC for superfluid helium cryogenics

et al. 2015

View full text Add to dashboard Cite

Wafer Temperature Control Using Helium Pressure and Observer-Based Model Predictive Control

Hayashi,

Takijiri,

Ueda

2023

ASME Letters in Dynamic Systems and Control

View full text Add to dashboard Cite

Stabilizing a wafer's temperature during plasma etching is a critical issue in semiconductor manufacturing. In this study, we propose feedback control of the wafer temperature using the pressure of helium gas (He) that is fed into the gap between the wafer and an electrostatic chuck (ESC) and an algorithm of the model predictive control (MPC) combined with an observer. The temperatures are measured only at the wafer edge zone and the ESC ceramic plate that are accessible during the process. The observer estimates wafer temperatures of center and edge zones and the injected heat power with the help of the measured edge zone temperature. The MPC determines the optimal He pressures based on the estimated temperatures to control both zone temperatures. The algorithm of the feedback control was formulated, and its validity was experimentally confirmed. Results showed that the observer worked well to estimate both zone wafer temperatures and the injected heat power. Results also showed that the temperatures were successfully controlled.

show abstract

Simulation Study on Application of Nonlinear Model Predictive Control to the Superfluid Helium Cryogenic Circuit*

Cited by 3 publications

References 10 publications

Non-linear moving horizon state estimation and control for the superfluid helium cryogenic circuit at the large Hadron Collider

Non-linear moving horizon state estimation and control for the superfluid helium cryogenic circuit at the large Hadron Collider

NMPC for superfluid helium cryogenics

Wafer Temperature Control Using Helium Pressure and Observer-Based Model Predictive Control

Contact Info

Product

Resources

About