Design of Dynamics of a Recuperative Catalytic Combustor: Enhancement in Operation and Control

2009 ◽  
Vol 4 (2) ◽  
Author(s):  
Wojciech M. Budzianowski ◽  
Ryszard Miller
Keyword(s):  
Control Algorithm ◽  
Response Analysis ◽  
Geometrical Parameters ◽  
Frequency Response Analysis ◽  
Fuel Temperature ◽  
Medium Term ◽  
Fuel Flow ◽  
Catalytic Combustor ◽  
And Control

The current contribution is aimed to describe and design the dynamics of the recuperative catalytic combustor. The step responses of the combustible concentration, fuel flow rate, fuel temperature and three manipulated variables are determined for the non-controlled combustor. The time delays, time constants and gains are determined for the temperatures measured in two points in the catalytic zone and its dependencies on the process and geometrical parameters are discussed. The frequency response analysis conducted shows that in the combustor with a higher time constant medium term input disturbances are effectively attenuated. In order to handle long term impulses of lean or rich fuels, the control strategy dedicated to the current combustor is proposed. It is verified in the example in which the frequently used control algorithm is applied to simulate the process control. The results show that the improvement is attained in combustor transient operation and control.

Frequency response analysis methods for open-loop servo drives and control systems

2020 ◽  
pp. 108-114
Author(s):  
Oleg B. Belonogov
Keyword(s):  
Frequency Response ◽  
Control Systems ◽  
Open Loop ◽  
Response Analysis ◽  
Frequency Response Analysis ◽  
Servo Drive ◽  
Response Data ◽  
Analysis Methods ◽  
Servo Drives ◽  
And Control

The paper presents results of development of frequency response analysis methods for open-loop servo drives and control systems, which use frequency response data of closed-loop servo drives and control systems obtained using Fourier and Laplace transforms of transient response calculated using their linear or linearized math models. The methods that have been developed can be used for approximate calculation of frequency response of servo drives and control systems based on their math models with slight non-linearities. Equations are derived for calculating frequency response of open-loop servo drives and control systems for several particular cases of feedback loop transfer function. The paper studies the efficiency of the developed frequency response analysis methods for open-loop servo drives and control systems. The obtained frequency response data for open-loop servo drives and control systems can be used for evaluating the amplitude and phase stability margins for these entities. Key words: frequency response; open-loop servo drive; control systems.

Test Results and Analytical Predictions for MIL-STD-167 Vibration Testing of a Direct Drive Compressor Supported on Magnetic Bearings

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Lawrence A. Hawkins ◽  
Rasish K. Khatri ◽  
Koman B. Nambiar
Keyword(s):  
Control Algorithm ◽  
Algorithm Design ◽  
Forced Response ◽  
Magnetic Bearings ◽  
Response Analysis ◽  
Test Results ◽  
Direct Drive ◽  
Vibration Testing ◽  
Analysis Methodology ◽  
And Control

External vibration testing was performed on a semihermetic, direct drive compressor on magnetic bearings intended for U.S. Navy Shipboard use. The compressor was placed on a U.S. Navy MIL-STD-167 shaker platform and driven at sinusoidal frequencies from 4 to 33 Hz at graduated displacements equal to a maximum of 1.5 Gs. During the machine design phase, a linear forced response analysis of the coupled rotordynamic system model of the rotor, housing, and magnetic bearings was performed to predict rotor/housing displacements and actuator loads. The results were used to guide bearing sizing and control algorithm design. The measured rotor motion and actuator currents correlated well with predictions at all tested frequencies, amplitudes, and orientations. Analysis methodology, test results, and comparisons are reported here.

Suppressed, but Not Forgotten

2011 ◽  
Vol 70 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Beat Meier ◽  
Anja König ◽  
Samuel Parak ◽  
Katharina Henke
Keyword(s):  
Memory Trace ◽  
Thought Suppression ◽  
Test Phase ◽  
Indirect Test ◽  
Final Test ◽  
Test Experiment ◽  
And Control ◽  
Cue Words ◽  
The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

Estimation and Reduction of Motor Input Surge Voltage using Frequency Response Analysis

2012 ◽  
Vol 132 (8) ◽  
pp. 630-637
Author(s):  
Toru Wakimoto ◽  
Yoshimitsu Takahashi ◽  
Norihito Kimura ◽  
Yukitoshi Narumi ◽  
Naoki Hayakawa
Keyword(s):  
Frequency Response ◽  
Response Analysis ◽  
Frequency Response Analysis

Identification of Trouble of Transformer by Frequency Response Analysis

2009 ◽  
Vol 129 (4) ◽  
pp. 517-525 ◽  
Author(s):  
Satoru Miyazaki ◽  
Yoshinobu Mizutani ◽  
Hiroshi Suzuki ◽  
Michiharu Ichikawa
Keyword(s):  
Frequency Response ◽  
Response Analysis ◽  
Frequency Response Analysis
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