Rotor Current Oriented Control Method of DFIG-DC System Without Stator Side Sensors

In this work we will present a control method for DC system – the so-called practical PID controller, where the inertia of both the derivative and the actuator is included. The original element in this paper consists of a comparative analysis of various controller stabilizing the position of motor shaft. In a system with ideal gain, K>0 ensures asymptotic stability of the closed-loop system. Taking into account this inertia along with the inertia of the derivative, we obtain limited values 0<Kp<Kgr. A similar restrictions apply to a system with delay.

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Adaptive Neural Networks Control Using Barrier Lyapunov Functions for DC Motor System with Time-Varying State Constraints

Complexity ◽

10.1155/2018/5082401 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Lei Ma ◽

Dapeng Li

Keyword(s):

State Constraints ◽

Control Method ◽

Time Varying ◽

Control Approach ◽

Dc System ◽

Full State ◽

Constraint Problem ◽

Barrier Lyapunov Functions ◽

Special Case ◽

Full State Constraints

This paper proposes an adaptive neural network (NN) control approach for a direct-current (DC) system with full state constraints. To guarantee that state constraints always remain in the asymmetric time-varying constraint regions, the asymmetric time-varying Barrier Lyapunov Function (BLF) is employed to structure an adaptive NN controller. As we all know that the constant constraint is only a special case of the time-varying constraint, hence, the proposed control method is more general for dealing with constraint problem as compared with the existing works on DC systems. As far as we know, this system is the first studied situations with time-varying constraints. Using Lyapunov analysis, all signals in the closed-loop system are proved to be bounded and the constraints are not violated. In this paper, the effectiveness of the control method is demonstrated by simulation results.

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A Novel Stator Frequency Control Method of DFIG-DC System Based on Regulating Air Gap Flux Vector

2020 IEEE Applied Power Electronics Conference and Exposition (APEC) ◽

10.1109/apec39645.2020.9124342 ◽

2020 ◽

Author(s):

Chao Wu ◽

Yingzong Jiao ◽

Peng Cheng ◽

Heng Nian ◽

Frede Blaabjerg

Keyword(s):

Control Method ◽

Frequency Control ◽

Air Gap ◽

Flux Vector ◽

Dc System

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Research on Additional Control Technology Based on Energy Storage System for Improving Power Transfer Capacity of Multi-Terminal AC/DC System with Low Cost

Energies ◽

10.3390/en13020495 ◽

2020 ◽

Vol 13 (2) ◽

pp. 495

Author(s):

Zheng Wu ◽

Laifu Li ◽

Yubo Yuan ◽

Xiaodong Yuan ◽

Chenyu Zhang ◽

...

Keyword(s):

Energy Storage ◽

Control Method ◽

Low Cost ◽

Storage System ◽

Energy Storage System ◽

Lyapunov Theory ◽

Power Transfer ◽

Dc System ◽

Additional Control ◽

Power Load

The multi-terminal AC/DC system will become one of the important forms of the future power grid. The negative impedance characteristic caused by the constant power load in the DC network will reduce the power transfer capacity between the terminals, especially when a grid fault occurs in AC system at any terminal. Energy storage has played an important role in improving the stability of AC and DC systems. This paper proposes an additional control method based on an energy storage system to improve system power transfer capacity with low cost. The state space model of two-terminal AC/DC system is established, and the feedback laws for additional control are further designed by Lyapunov theory. Furthermore, the additional control strategies based on the energy storage system is built, without changing the existing control system of each control object. Finally, the corresponding system simulation model is established by Matlab/Simulink for analysis and verification. The research results show that the proposed additional control method is effective. The power transfer limitation can be overcome by only adding small damping energy with the stable DC voltages under large disturbances, and the power transfer capacity between the terminals can be significantly improved with low control cost.

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Conductance-controlled global-compensation-type shunt active power filter

Archives of Electrical Engineering ◽

10.1515/aee-2015-0022 ◽

2015 ◽

Vol 64 (2) ◽

pp. 259-275 ◽

Cited By ~ 6

Author(s):

Andrzej Szromba

Keyword(s):

Control Method ◽

Current Source ◽

Active Power Filter ◽

Active Power ◽

Active Filter ◽

Active Filters ◽

Voltage Source ◽

Shunt Active Power Filter ◽

Dc System ◽

Power Filter

Abstract This paper presents a load equivalent conductance based control method for a shunt active power filter. The principle of energy balance in the circuit, which means between supplying source - active filter - load, is used to obtain the control formula. The natural inertia of the active filter action is exploited, so no PI regulators are needed. The active filter can compensate for non-active current and, additionally, can stabilise the supplying source active power. In a case of generating loads energy harvesting is possible. The presented method is useful as well for voltage-source as current-source inverter based active filters, and for DC system as well as for AC single- or three-phase one.

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