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Active filters are known as the best tools for harmonic mitigation as well as reactive power compensation, load balancing, voltage regulation, and voltage flicker regulation on the power lines. To introduce the operation of active filters in education, it is a good method to use a software, named SPICE. It is a good choice, because it has a high level of objects for simulation, and good presentation...
Loss allocation to each user based on fair and justice is the main content of electrical power transmission cost reasonable allocation in Electricity Market. Making use of the uniqueness of Shapley value and distinctive features of shapley theorem, power sources and load are regard as players in a union. That is transform power source to equivalent voltage source and load to impedance based on Thevenin...
Due to the benefits to our environment and high economical efficiency, the local distribution network have been integrated with more and more renewable power resources, such as wind power. By using probabilistic load flow, this paper presents a new method to investigate distribution network's voltage security caused by wind power integrated. Giving wind speed randomness and other stochastic disturbances,...
The research on the application of the 3-phase high power PWM (Pulse Width Modulation) rectifier in the battery charge and discharge device has been a hotspot in the field of power electronics and control. As the traditional PID controller is difficult to achieve the optimum parameters, this paper proposes a new control method of PWM rectifier based on Genetic Algorithm (GA). The design of the PWM...
Some methods of detecting harmonic current in the power system were analyzed in this paper, the models were built and simulated with Matlab simpowersystem module, result indicates ip-iq method can detect harmonic currents in the balanced power system and as long as doing an improvement slightly, can use single phase ip-iq to check the harmonic electric current in the single phase system, or to apply...
Nowadays, most of the electrical railway tractions, especially the high-speed tractions are using AC-DC-AC power driving system. The best choice for the AC-DC link is four-quadrant PWM rectifier, which can provide controllable DC link voltage and better power factor for the grid. In high power drive applications, the switch frequency of the power semiconductor device cannot be very high, usually less...
PWM rectifier technology is introduced to the main Power Circuit of the charger for aircraft battery to enhance the charging efficiency of aircraft battery and improve its long term reliability and save its life in this paper. A new strategy of DPC Based on the Space Vector Modulation (SVM) is used in PWM rectifier, Meanwhile, a fuzzy PI controller is designed in DC voltage control loop. The simulation...
Because of the higher efficiency, higher power factor, higher power density and better dynamic performance, there is ever increasing attention to applying permanent magnet synchronous motors (PMSM) to traction system. In this paper, the parameter selection of the permanent magnet traction drive motor (PMTDM) was carried out. Some useful conclusion was obtained. At last, a motor design program was...
This paper proposes an application of Fast Voltage Stability Index (FVSI) to Reactive Power Planning (RPP) using Evolutionary Programming (EP). FVSI is used to identify the weak buses for the RPP problem which involves experimental process of voltage stability analysis based on the load variation. The point at which FVSI close to unity indicates the maximum possible connected load and the bus with...
A decentralized controller for the synchronization of two remote parallel voltage source inverters used to supply train auxiliaries is presented. A modular hybrid dynamic model of the entire power electronic apparatus is constructed; possible unbalanced line and load impedances are also considered. The power sharing between the converters is obtained by designing a droop controller based on local...
This paper proposes an application of Evolutionary Algorithms (EAs) such as Differential Evolution (DE), Evolutionary Programming (EP), Real coded Genetic Algorithm (RGA), Covariance Matrix Adaptation Evolution Strategy (CMAES) and Particle Swarm Optimization (PSO) to Reactive Power Planning (RPP) problem. RPP is a non-smooth and non-differentiable optimization problem for a multiobjective function...
This paper proposes a combined Secondary and Tertiary Voltage Regulation (SVR+TVR) methodology based on real-time optimal power flows (OPFs) to periodically update the generators' voltage regulator set points. Minimum active power losses (MAPL) and maximum loadability (ML) OPF approaches are used for the proposed SVR+TVR control. The presented technique is compared against a “classical” SVR control,...
This paper addresses the problem of coordinating voltage control in a large-scale power system partitioned into control areas operated by independent utilities. Two types of coordination modes are considered to obtain settings for tap changers, generator voltages, and reactive power injections from compensation devices. First, it is supposed that a supervisor entity, with full knowledge and control...
Dish-Stirling systems are a form of concentrating solar power (CSP) emerging as an efficient and reliable source of renewable energy. Various technical hurdles are involved in the grid interconnection of dish-Stirling systems, particularly with issues related to power factor correction, low voltage ride-through capability, and reactive power planning. While there are no grid-interconnection requirements...
This paper explores the performance of alternative voltage control strategy applied to direct drive synchronous wind generators, more specifically with permanent magnetic (PMSG). The reactive power control of the grid-side converter is investigated for voltage control purposes. In Brazil, the Grid National Operator (ONS) requires that wind turbines stay connected to the grid during voltage dips, but...
The paper investigates the possibility of ranking synchronous generators in a power system according to their contribution to system angular and voltage stability. The aim of this research is to establish fast semi-analytical methodology, i.e., avoiding transient simulations, to determine which synchronous generators can be safely disconnected from the network or replaced by other types of generators,...
This paper presents a comparative analysis about the influences of three inverter-based distributed generators control modes on several important aspects of distribution networks. The control modes investigated are constant current, constant reactive and active power, and constant voltage and active power. The investigated aspects are steady-state voltage profile, network losses, short-circuit currents...
This paper investigates the use of multi-linear regression models (MLRMs) and machine learning techniques for online voltage stability margin prediction. The methodology relies upon the relationship between system wide reactive power reserves and voltage stability margin. A comprehensive voltage stability assessment considering an extensive contingency list and several load increase directions is...
Due to growing competition in the electricity market, the drive for efficient, stable and secure grid operation makes voltage control in the transmission grid relevant. A solution that has potential is to increase the effectiveness of the ancillary service by automatic fast control. The paper describes a Wide Area Voltage Regulation (V-WAR) that fits this framework. The V-WAR is based on Secondary...
Wind farms typically contain a variety of voltage control equipment including tap-changing transformers, switched capacitors, SVCs, STATCOMs, and the generators themselves. This paper focuses on the control of this equipment by addressing three major issues. The first is the ability of wind turbines to provide reactive power; voltage saturation in the collector system often limits the reactive power...
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