Power Control

Open Access Article

1 - Handoff Optimization for Joint Base Station Association and Power Control with Proportional Fairness in NOMA Small-Cell Networks
Sina Pirnia Hamidreza Bakhshi Mohamad Dosaranian-Moghadam Ramin Khosravi

10.30495/jce.2022.1967097.1172

The handoff rate and load balancing are two important issues that have a great impact on the spectrum and energy efficiency in the small cell networks. This paper investigates the handoff optimization in small cell networks with power-domain non-orthogonal multiple acce More

The handoff rate and load balancing are two important issues that have a great impact on the spectrum and energy efficiency in the small cell networks. This paper investigates the handoff optimization in small cell networks with power-domain non-orthogonal multiple access that uses successive interference cancellation, considering the fairness among base stations. We study the joint base station association and power control problem by considering the motion of mobile users and load balancing in the small cell networks. Under the maximum allowable transmit power and minimum average-rate constraints, two optimization problems are formulated using the number of associated mobile users, the number of handoffs, and the transmit power of all MUs. The total power consumption minimization and the system-wide and handoff utility maximization problems are combined into a single-stage optimization problem through the weighted sum method. We solve the formulated problem using a game theory-based algorithm and primal decomposition theory. The simulation results show that our proposed algorithm can significantly reduce the frequent handoffs and bring a fair power-controlled BS association in small cell networks. Manuscript profile

Open Access Article

2 - Improved SNR in Location with UWB Using Power Control Algorithms
Aziz Szfadoust Hosein Momenzadeh Haghighi

In indoor localization using ultra-wide band, the signal-to-noise ratio (SNR) has a significant role in localization. In indoor localization the factors such as the effect of the of noise phenomenon, the effect of multi-path phenomenon and the effect of non-line of sigh More

In indoor localization using ultra-wide band, the signal-to-noise ratio (SNR) has a significant role in localization. In indoor localization the factors such as the effect of the of noise phenomenon, the effect of multi-path phenomenon and the effect of non-line of sight emission have reduced the accuracy and precision of localization in indoor environment. Localization with ultra-wideband is a convenient positioning solution in indoor space. Enhancement of SNR in this way increases the accuracy and precision of indoor localization in the ultra-wide band. Enhancement of SNR using power control algorithms is the proposed solution in this paper. Power control algorithms are used in transmitter and receiver devices. Power control is performed on transmit power. The value of SNR in line of sight and non-line of sight has been evaluated. Using power control algorithms, we can see the enhancement of SNR in both in line of sight and non-line of sight. Manuscript profile

Open Access Article

3 - Integral Sliding Mode Based Direct Power Control of Brushless Doubly Fed Induction Generators
Ramtin Sadeghi Mohammad Reza Agha kashkooli Seyed Mohammad Madani

10.30486/teeges.2022.1959045.1012

This paper proposes an integral sliding mode direct power control (ISM-DPC) strategy for brushless doubly fed induction generators. Two widely applied control strategies are available for this type of generators: hysteresis-based direct power control and vector control. More

This paper proposes an integral sliding mode direct power control (ISM-DPC) strategy for brushless doubly fed induction generators. Two widely applied control strategies are available for this type of generators: hysteresis-based direct power control and vector control. Direct power control suffers from high power ripples and current distortions produced by variable switching frequency. Moreover, the tuning issues of PI controller, which are highly reliant on machine parameters and operating conditions, and necessity of a phase-locked-loop for frame alignment are accounted as limitation of these methods. The proposed integral sliding mode strategy directly controls active and reactive power to provide fast dynamic response and zero steady-state error. This method is developed in the control winding reference frame to avoid the application of PLL. A large-scale brushless doubly fed induction generator (BDFIG) is simulated to validate the effectiveness and robustness of the proposed ISM-DPC method in comparison with widely applied methods, vector control and direct power control. Manuscript profile

Open Access Article

4 - Optimization of Centralized Control of Volt/Var in Transmission Systems Based on Economic Dispatch and Harmony Search Algorithm
Mohammad Mahdi Rezaei Kamal Rouhollahi Seyed Mohammad Madani

10.30486/teeges.2022.1968162.1038

Maintaining the voltage profile of the power system within the appropriate bound has been a key factor for the proper operation of system equipment, especially during disturbances. However, due to the uncertainty of the load powers and the limitation in equipment rating More

Maintaining the voltage profile of the power system within the appropriate bound has been a key factor for the proper operation of system equipment, especially during disturbances. However, due to the uncertainty of the load powers and the limitation in equipment ratings, achieving this goal has become a challenge. High voltage substations play an important role in voltage control, because these substations can be a primary connection point between the high voltage transmission network and the distribution system. The nature of local voltage control, the variety of control tools and the interaction between them, have made this type of control difficult. In this paper, a centralized voltage/reactive power control method is presented based on phasors measured by PMUs installed in grid substations. In this method, the tap changing of transformers and step switching of capacitor banks have been determined by the central controller based on system voltages and network equations. In addition, the appropriate values of the operating point of the generators have been carried out based on economic dispatch in each period of optimization. The consistent and efficiency of the proposed method have been investigated through simulation in MATLAB software environment. Manuscript profile

Open Access Article

5 - Industrial Networks Performance Enhancement Using Fuzzy ‎Controlled Distributed Generation
Naser Ghasemi Seyyed Mehdi Hosseini

Manuscript profile

Open Access Article

6 - Vector Control of Speed and Reactive Power of Brushless Doubly-Fed Induction Generator Based on Nonlinear Control Approach
Davoud Abootorabi Zarchi Hossein Abootorabi Zarchi Hamidreza Mosaddegh Hesar Mohammad Ali Salahmanesh

The brushless doubly fed induction generator (BDFIG) is one of the main members of doubly fed electrical generators which has come close to commercialization in recent years. This generator has some of outstanding features of squirrel cage induction generator and conven More

The brushless doubly fed induction generator (BDFIG) is one of the main members of doubly fed electrical generators which has come close to commercialization in recent years. This generator has some of outstanding features of squirrel cage induction generator and conventional synchronous generator, and at the same time, it requires a partially rated converter. One of the major challenges in the evolution of this generator is the problem of controlling it and the necessity of having a suitable and efficient controller to stabilize the generator in the operating speed range. Therefore, in this paper, a comprehensive vector control scheme based on nonlinear control methods is proposed. Accordingly, a reference model controller fulfills the control of rotor speed. In addition, for simultaneous control of reactive power and torque, a combined approach based on sliding mode and PI controllers are used. The simulation results show in presence of the mentioned control structure, the dynamic response of system in different conditions such as change of mechanical input power and reference speed variation is much more appropriate than when a linear controller is used. Manuscript profile

Open Access Article

7 - Dynamic Response and Low-Voltage Ride-Through Improvement for A DFIG, Using an Integral Sliding Mode Controller with an Adjustable Reactive Power Reference Value
Hamid Moghadasi Mohammadreza Moradian

In this paper, a sliding mode controller with an adjustable reactive power reference value is proposed. To improve the performance of the controller in a steady-state, an Integral Sliding Mode Control is designed and used. In addition, to improve the low-voltage ride-th More

In this paper, a sliding mode controller with an adjustable reactive power reference value is proposed. To improve the performance of the controller in a steady-state, an Integral Sliding Mode Control is designed and used. In addition, to improve the low-voltage ride-through capability in the fault condition, a reactive power controller with an adjustable reference value is proposed. The performance of this control system, during the power track, is compared with two other control systems that have a fixed reference for reactive power and are based on SMC and PI controllers in 9 different fault modes. These 9 different modes include one-phase, two-phase, and three-phase short circuit faults in the sub-synchronous, synchronous, and super-synchronous mode of operation for DFIG. The proposed method has been implemented in Simulink/MATLAB software. The simulation results confirm the capability and effectiveness of the proposed control system in comparison with two other aforementioned control systems. Manuscript profile

Open Access Article

8 - Investigation of Reactive Power Control Effects on Flicker and Harmonics Emission of a DFIG Wind Turbine
Amir Nagizadeh Ghoogdareh Aref Doroudi Mohammad Poormonfared Azimi

One of the most important power quality aspects in wind farms is voltage fluctuation or flicker which should be investigated due to the nature of wind speed variations. These variations result in power and voltage fluctuations at the load bus. Moreover, the wind generat More

One of the most important power quality aspects in wind farms is voltage fluctuation or flicker which should be investigated due to the nature of wind speed variations. These variations result in power and voltage fluctuations at the load bus. Moreover, the wind generation systems may be assumed as a harmonics source because of their power electronic converters. There are numerous factors that affect flicker and harmonic emission of grid-connected wind turbines during continuous operation, such as wind characteristics (e.g. mean wind speed, turbulence intensity), type of generator and grid conditions (e.g. short circuit capacity, grid impedance angle). In this paper, an IEC based flickermeter is first modeled and then a variable speed wind turbine has been simulated by Matlab/Simulink software. The flicker and harmonics emissions of wind turbines equipped with DFIG during continuous operation and using output reactive control are investigated. The simulation results show that control of wind turbine output reactive power is an effective means for flicker mitigation during continuous operation. However, there should be a compromise between flicker reduction and harmonics level increase to enhance the whole power quality of wind turbine. Manuscript profile

Open Access Article