Are evoked stim-T modulations more suitable for closed-loop frequency control than stim-T intervals?

This paper presents an active disturbance rejection control (ADRC) technique for load frequency control of a wind integrated power system when communication delays are considered. To improve the stability of frequency control, equivalent input disturbances (EID) compensation is used to eliminate the influence of the load variation. In wind integrated power systems, two area controllers are designed to guarantee the stability of the overall closed-loop system. First, a simplified frequency response model of the wind integrated time-delay power system was established. Then the state-space model of the closed-loop system was built by employing state observers. The system stability conditions and controller parameters can be solved by some linear matrix inequalities (LMIs) forms. Finally, the case studies were tested using MATLAB/SIMULINK software and the simulation results show its robustness and effectiveness to maintain power-system stability.

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Are evoked stim-T modulations more suitable for closed-loop frequency control than stim-T intervals?

EP Europace ◽

10.1016/eupace/2.supplement_1.a64-a ◽

2001 ◽

Vol 2 (Supplement_1) ◽

pp. A64-A64

Author(s):

R. Heinze ◽

C. Richter ◽

J. Hundertmark ◽

H. Schüller* ◽

K. Stangl

Keyword(s):

Closed Loop ◽

Frequency Control

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Sensorless Closed-Loop Voltage and Frequency Control of Stand-Alone DFIGs Introducing Direct Flux-Vector Control

IEEE Transactions on Industrial Electronics ◽

10.1109/tie.2019.2955421 ◽

2020 ◽

Vol 67 (7) ◽

pp. 6078-6088

Author(s):

Majid Rostami ◽

Seyed M. Madani ◽

Sul Ademi

Keyword(s):

Vector Control ◽

Closed Loop ◽

Frequency Control ◽

Flux Vector

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Capacitive-Based, Closed-Loop Frequency Control of Substrate-Integrated Cavity Tunable Filters

International Symposium on Microelectronics ◽

10.4071/isom-thp24 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 000826-000831 ◽

Cited By ~ 2

Author(s):

Shahrokh Saeedi ◽

William S. Wilson ◽

Tyler R. Ashley ◽

Hjalti H. Sigmarsson ◽

Juseop Lee

Keyword(s):

Feedback Control ◽

Closed Loop ◽

Frequency Tuning ◽

Frequency Control ◽

Center Frequency ◽

Evanescent Mode ◽

Loop Control ◽

Custom Made ◽

Metal Insulator Metal ◽

Loop Feedback

In this paper, we present an integrated capacitive sensing technique that can be used to achieve closed-loop feedback control of variable capacitors. The technique is well suited for diaphragm-based actuators that can be used to tune the center frequency of microwave reconfigurable filters. A commercially available capaci-tance-to-digital converter is used to measure the capacitance of a custom-made monitoring capacitor. This capacitor is completely external to the filter structure and does not contribute to any added losses. A tunable, second-order, bandpass filter –using substrate-integrated, evanescent-mode cavity resonators– is created to demonstrate the concept. The frequency tuning is achieved using piezoelectric actuators to displace a flexible copper diaphragm that forms the top part of the loading capacitor. The monitoring capacitor consists of a second cavity that is mounted above the actuator forming a second air-filled, metal-insulator-metal capacitor. There exists a direct relationship between the monitoring capacitance and the loading capacitance in the evanescent-mode cavity. Therefore, by tracking the monitoring capacitance the center frequency of the filter can be monitored, which allows for direct in-situ closed-loop control of the filter. An algorithm for the tuning operation is presented, which includes an automatic calibration technique to initialize the controller. The effectiveness and repeatability of the technique is evaluated as the filter is tuned from 3.3 GHz to 3.7 GHz. Having stable feedback control integrated with this type of evanescent-mode cavity filters, brings the technology one step closer to actual fielding.

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Simulation Analysis of Vector Control System with Material Properties Based on Mine Fanner Load and Energy Saving

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.848.178 ◽

2013 ◽

Vol 848 ◽

pp. 178-182

Author(s):

Yan Xiang Wu ◽

Chao Qun Zhou ◽

Chao Jun Zhang ◽

Pu Sun

Keyword(s):

Control System ◽

Vector Control ◽

Closed Loop ◽

Simulation Analysis ◽

Frequency Control ◽

Asynchronous Motor ◽

Control Performance ◽

Field Oriented Vector Control ◽

Vector Control System ◽

The Mathematical Model

According to the characteristics of mine fanner, the running characteristic and requirements of load was analyzed, and the fanner control system was simulated by using frequency control technology in this thesis. The speed flux double closed loop vector control system was designed by using the principle of the rotor field-oriented vector control and the mathematical model of asynchronous motor. The simulation model was simulated and analysised by MATLAB/Simulink. The result indicated that the vector control system can not only quickly responded to the change of the load torque but also have good speed control performance, and the mine fanner operation requirements was satisfied.

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Load frequency control of a hydro dominating interconnected power system

10.51415/10321/3654 ◽

2020 ◽

Author(s):

◽

Milan Joshi

Keyword(s):

Power System ◽

Closed Loop ◽

Frequency Control ◽

Linear Quadratic Regulator ◽

Load Frequency Control ◽

Accurate Estimation ◽

Renewable Energy Resources ◽

Linear Quadratic ◽

Random Load ◽

Load Frequency

Energy is one of the vital figures that impact the development of civilization in the 21st century. It has been projected that by the year 2050, global energy needs will be satisfied by renewable sources. Among these renewable energy resources hydropower is available worldwide with relatively cheaper accessibility for most of the communities. Nevertheless, hydropower's control architecture raises concern for the system operators in terms of preserving the Load Frequency Control (LFC) services due to the elongated response time of hydro turbines in catering for the varying load demands. The varying load demands are inevitable in the power system due to different clients’ energy consumption patterns at different times. This, therefore, places changing control framework requests as per the requirement of diverse clients. Hence, the research proposes and demonstrates the connection of the hydro-hydro framework through the AC tie- line for LFC. The Linear Quadratic Regulator (LQR) is a plan for hydro overseeing framework in discrete mode. The application derived is displayed through closed- loop feedback gains and closed-loop eigenvalues. In the expansion model, the positive effect of a Unified Power Flow Controller (UPFC) and Redox Flow Battery (RFB) in LFC studies is investigated. This proposition moreover shows the joint endeavors of Fuzzy Logic (FL) as well as Proportional Integral Derivative (PID), with control gains well-calculated, through Particle Swarm Optimization (PSO) result into a robust FL-PSO-PID for LFC of the connected hydro framework. The different errors are defined to assess the yield as well as the execution of the FL-PSO-PID. The yield appears through a decline in blunder values as well as minimization in framework responses from accurate estimation for the LFC under various working conditions such as non- linearity, random load alteration, and parametric move as a result of a precise estimate. In the expansion, the effect of energy storage devices is also investigated to understand the enhancement provided frequency control of the hydro system, and the result obtained shows their effectiveness. Finally, the outcomes and future extent of this investigation work have been presented.

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