Advanced Energy Technologies
Moslem Geravandi; Hassan Moradi CheshmehBeigi
Abstract
The ability of power systems against severe events shows their increased resilience, which in turn reduces the operation costs and recovery time of the system. This study presents a new resilient stochastic unit commitment model using the frequency change rate as a new index of system resilience. Furthermore, ...
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The ability of power systems against severe events shows their increased resilience, which in turn reduces the operation costs and recovery time of the system. This study presents a new resilient stochastic unit commitment model using the frequency change rate as a new index of system resilience. Furthermore, uncertainties of wind and solar power plants and demanded load are considered simultaneously. In the proposed method that considers the occurrence of a destructive incident in important production units in the worst-case scenarios and by using the generation capacity, adaptive frequency load shedding, and interrupting contracts, an effective strategy was provided to solve the unit commitment problem of thermal units to prevent instability in system frequency and to minimize unwanted load shedding. The proposed model was tested and evaluated on the IEEE 39-bus system with a wind power plant and a solar power plant. Moreover, the results obtained from simulation were reported. The effectiveness of this innovative approach in increasing the resilience of the power system against different degrees of uncertainty was confirmed based on the results.
Advanced Energy Technologies
Shokoofeh Bagheri; Hassan Moradi CheshmehBeigi
Abstract
Today, the presence of energy storage systems along with the alternative nature of renewable energy sources has become undeniable and one of these types of systems is battery energy storage systems. The most important factor in studying the stability of DC microgrids (DCMGs) is the stabilization of the ...
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Today, the presence of energy storage systems along with the alternative nature of renewable energy sources has become undeniable and one of these types of systems is battery energy storage systems. The most important factor in studying the stability of DC microgrids (DCMGs) is the stabilization of the DC bus voltage when an error occurs on its reference value. Therefore, batteries along with power electronic converters play an important role in maintaining DCMG stability. In this paper, the use of Cascaded Buck-Boost Converter (CBBC) can be considered as a suitable alternative to bidirectional buck-boost converter due to such advantages as high power density, 98 % efficiency, and higher operating temperature in battery. The control strategy is applied in the microgrid implemented in the converter system set with storage, and Virtual DC Machine (VDCM) is based on charging and discharging battery through CBBC. In the studied control method, the theoretical properties of the DC machine, which is responsible for amplifying the virtual inertia in the system, are directed to the CBBC for correct switching. VDCM can be changed from motoring to generating mode or vice versa, regardless of mechanical machinery. Therefore, the proposed control system is simulated in an islanded DCMG in Matlab/Simulink and the stability of the studied system is analyzed according to the small-signal model of the proposed control and converter units. According to the simulation results and small-signal model analysis, the stability of the proposed idea under different scenarios is confirmed.
Advanced Energy Technologies
Vahid Nazari; Mohammad Hossein Mousavi; Hassan Moradi CheshmehBeigi
Abstract
Over the past decades, power engineers have begun to connect power grids to other networks such as microgrids associated with renewable units using long transmission lines to provide higher reliability and greater efficiency in production and distribution besides saving resources. However, many dynamic ...
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Over the past decades, power engineers have begun to connect power grids to other networks such as microgrids associated with renewable units using long transmission lines to provide higher reliability and greater efficiency in production and distribution besides saving resources. However, many dynamic problems such as low frequency oscillations were observed as a result of these connections. Low frequency oscillation is a normal phenomenon in most power systems that causes perturbations and, thus, the grid stability and damping process are of paramount importance. In this paper, to attenuate these oscillations, a novel method for designing Power System Stabilizer (PSS) is presented via Linear Parameter-Varying (LPV) approach for a Single Machine Infinite Bus system (SMIB). Because the system under study is subject to frequent load and production changes, designing the stabilizer based on the nominal model may not yield the desired performance. To guarantee the flexibility of the stabilizer with respect to the aforementioned issues, the power system polytopic representation is used. In order to apply the new method, the nonlinear equations of the system at each operating point, located in a polytope, are parametrically linearized by scheduling variables. Scheduling variables can be measured online in any operating point. By using this model and following the H∞ synthesis, feedback theories, and Linear Matrix Inequalities (LMIs), LPV controllers at all operating points are obtained. Finally, the simulation results verify the effectiveness of the proposed controller over classic and robust controllers with regard to uncertainties and changes in system conditions.
Environmental Impacts and Sustainability
Roya Pashangpour; Faramarz Faghihi; Soodabeh Soleymani; Hassan Moradi CheshmehBeigi
Abstract
There has been a global effort to reduce the amount of greenhouse gas emissions. In an electric resource scheduling, emission dispatch and load economic dispatch problems should be considered. Using renewable energy resources (RESs), especially wind and solar, can be effective in cutting back emissions ...
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There has been a global effort to reduce the amount of greenhouse gas emissions. In an electric resource scheduling, emission dispatch and load economic dispatch problems should be considered. Using renewable energy resources (RESs), especially wind and solar, can be effective in cutting back emissions associated with power system. Further, the application of electric vehicles (EV) capable of being connected to power grid reduces the pollution level in the transportation sector. This paper investigates a resource scheduling with uncertain behavior of RESs and EVs by considering the penalty factors of emission for each conventional power plant in Hormozgan province of Iran for a 10-year period from 2016 to 2026. In this study, combined-cycle and thermal units are also taken into account. The CPLEX Solver is utilized for resource scheduling problem in GAMS. For combined-cycle power plants, ramp rate constraints are also included. To investigate the impact of uncertainties, different scenarios are considered. The obtained results demonstrate that Hormozgan province has a decent potential of utilizing RESs and EVs to achieve pollution reduction and optimal cost.
Advanced Energy Technologies
Maryam Rahmani; Faramarz Faghihi; Hassan Moradi CheshmehBeigi; Seyed Mehdi Hosseini
Abstract
In this paper, the effect of a static synchronous compensator (STATCOM) influence on the frequency of islanded microgrids based on frequency control using fuzzy cooperative control is investigated. To achieve fast frequency control, instantaneous power balance between generation and consumption is inevitable, ...
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In this paper, the effect of a static synchronous compensator (STATCOM) influence on the frequency of islanded microgrids based on frequency control using fuzzy cooperative control is investigated. To achieve fast frequency control, instantaneous power balance between generation and consumption is inevitable, and it can be supplied through energy storage systems such as battery with a proper frequency control method. Besides, the frequency control of islanded microgrids could be studied under different circumstances, where one aspect analyzed is added to a flexible AC transmission system (FACTS) device, such as STATCOM, in the microgrids. Although STATCOM is charged with improving the voltage profile, it can affect frequency stability by adjusting the voltage very quickly. Due to the importance of refining frequency stability, two controller methods are compared: a classic PI controller and a fuzzy PID controller. Accordingly, the performance of STATCOM is evaluated via two scenarios. Based on simulation results, by applying the fuzzy PID controller to the microgrid, STATCOM can reach the nominal frequency. Moreover, with greater validation and investigation of this topic, this device could be an agreeable alternative to the battery energy storage system (BESS).
Advanced Energy Technologies
Neda Azizi; Hassan Moradi CheshmehBeigi
Abstract
This paper focuses on improving the active and reactive power control of Wind Energy Conversion System (WECS) by employing the Battery Energy Storage System (BESS) and controlling the frequency and voltage regulation instantaneously. The proposed power control scheme is composed of two control loops ...
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This paper focuses on improving the active and reactive power control of Wind Energy Conversion System (WECS) by employing the Battery Energy Storage System (BESS) and controlling the frequency and voltage regulation instantaneously. The proposed power control scheme is composed of two control loops so that they are implemented and designed for active power control and controlling the reactive power, respectively, which both are equipped with PI type controllers. In addition, two control loops were utilized to control the frequency and voltage on the rotor side converter under balance and unbalance grid conditions. In this paper, the presented control strategy optimally tuned all the parameters of controllers at the same time by utilizing a mixed integer nonlinear optimization programming and solved by the ICA algorithm. Moreover, in order to demonstrate the effectiveness of the proposed strategy, non-linear time domain simulations were carried out in MATLAB software. The obtained simulation results verified that the proposed control scheme efficiently utilize BESS to control the active and reactive power control and confirm the effectiveness of the proposed strategy under the balanced and unbalanced grid conditions.
