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Abstract: A lot of work has been done in the field of multi-valued model checking home and abroad. But some research works are not perfect. Some problems in the semantic definitions of temporal operators and corresponding model checking algorithms are found in the paper “Model Checking Using Partial Kripke Structure with 3-Valued Temporal Logic”. Some counterexamples are given to show these errors. On the basis of the discussion, some sound semantic definitions of temporal operators and correct algorithms of model checking for some temporal operators are given. [Copyright &y& Elsevier]

Heat demand forecasting is in one form or another an integrated part of most optimisation solutions for district heating and cooling (DHC). Since DHC systems are demand driven, the ability to forecast this behaviour becomes an important part of most overall energy efficiency efforts. This paper presents the current status and results from extensive work in the development, implementation and operational service of online machine learning algorithms for demand forecasting. Recent results and experiences are compared to results predicted by previous work done by the authors. The prior work, based mainly on certain decision tree based regression algorithms, is expanded to include other forms of decision tree solutions as well as neural network based approaches. These algorithms are analysed both individually and combined in an ensemble solution. Furthermore, the paper also describes the practical implementation and commissioning of the system in two different operational settings where the data streams are analysed online in real-time. It is shown that the results are in line with expectations based on prior work, and mat the demand predictions have a robust behaviour within acceptable error margins. Applications of such predictions in relation to intelligent network controllers for district heating are explored and the initial results of such systems are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, direct torque control (DTC) algorithms for double star permanent magnet synchronous machine alimented by two inverters is described. The double star permanent magnet synchronous machine has two sets of three-phase stator windings spatially shifted up by an angle γ=300. The double star permanent magnet synchronous is used in areas of high power industrial applications such as traction and naval propulsion. Because constitute an advantageous choice compared to classical synchronous machine, because of the relatively low torque produced. This machine is controlled by tree level direct torque with speed regulator PI, replaced by the sliding mode regulator to improve the results obtained. The implementation of the DTC multi-level applied to a double star permanent magnet synchronous machine is validated with simulated results. In this paper a method for modeling and simulation of double star permanent magnet synchronous motor drive MATLAB/Simulink. [Copyright &y& Elsevier]

Abstract: The requirements of device under the multi-mission of monitoring, protecting, controlling and communicating is discussed in this paper to bring forward a design of dual CPU structure with ARM & DSP for microprocessor protection. Via the comparative analysis of several common algorithms, the algorithm of FFT, which can make the controlling of calculation accuracy easier and has a filter feature inherently, is selected to analyze the sampling data of protector and calculates relative electrical parameters. Relevant program is written for distance protection in 110kV transmissions, then debugging on software and hardware is made. The results show that the design of DSP & ARM based-microprocessor protection presented in this paper is feasible; such a device has simple and reliable circuit structure and is expandable in both software and hardware. [Copyright &y& Elsevier]

Abstract: This paper modifies and improves the algorithm of sight distance triangle according to the traffic flow and geometric features of intersections. Using the modified crossable intervals and the traffic volume on the secondary road and the obstacles within the improved sight distance triangle as selection criteria, we put forward the control mode selection flow diagram of plane intersections in this paper, hoping to quantize the selection criteria, as well as normalize and visualize the selection process.Finally,this paper checks the accuracy and reliability of the model through the analysis of a case. [Copyright &y& Elsevier]

Abstract: This paper described the structure of a Shunt Active Power Filter system and compared various methods of active power filter harmonic detection, then the improved adaptive algorithm was used in active power filter harmonic detection; as regards the control strategy, the control method that based on optimal voltage space vector hysteresis current was presented in this paper for tracking control, And by using Matlab/Simulink simulation software, the Adaptive filter detection system and control model of Three-phase three-wire Shunt Active Power Filter were established. Simulation results showed that the selected detection method and control strategy of harmonic current played a fairly good compensation role on the harmonics which was generated by nonlinear loads and had a good dynamic compensation performance. [Copyright &y& Elsevier]

Abstract: This paper shows the determination of typical load profiles (TLPs) by using Fuzzy C-Means (FCM) clustering and Probability Neural Network (PNN) classification method. Load profiles provide useful information on electricity consumption to both consumers and suppliers. Precise knowledge on consumer''s electricity consumption becomes essential for the suppliers to design tariffs, load balancing, load planning, etc. As for consumers, such knowledge is important for them to keep track of their electricity consumption and to enable them to take part in retail market especially for those who do not have appropriate metering equipment. Hence, an effective, fast and cheap method to obtain load profile has to be developed. Objectives of this paper are to obtain groups of TLPs by using FCM clustering and to assign TLPs using PNN algorithm. One of the main issues in FCM clustering is the determination of optimal number of cluster. This paper proposes optimal number of cluster determination by using Davies-Bouldin index. PNN network is trained to directly allocate the TLPs to the representative groups of consumers. The data used in this project are obtained from Tenaga Nasional Berhad (TNB). [Copyright &y& Elsevier]

Abstract: A new design of decentralized load-frequency controller for interconnected power systems with ac-dc parallel using Particle Swarm Optimization (PSO) algorithm is proposed in this paper. A HVDC link is connected in parallel with an existing ac tie-line to stabilize the frequency oscillations of the ac system. Any optimum controller selected for load frequency control of interconnected power systems should not only stabilize the power system but also reduce the system frequency and tie line power oscillations and settling time of the output responses. In practice Load Frequency Control (LFC) systems use simple Proportional Integral (PI) or Integral (I) controller parameters are usually tuned based on classical or trial-and-error approaches, they are incapable of obtaining good dynamic performance for various load change scenarios in multi-area power system. For this reason, in this paper the PI and I control parameters are tuned based on PSO algorithm method for the LFC control in the two-area power system. A two area interconnected thermal power system is considered to demonstrate the validity of the proposed controller. The simulation results show that the proposed controller provides better dynamic responses with minimal frequency and tie-line power deviations, quick settling time and guarantees closed-loop stability margin. [Copyright &y& Elsevier]

Abstract: A large AC generator is an important component of the power system. Researches on the AC generator relaying for the next-generation ECMS and an efficient operation of protection control system are necessary. These require developments on detailed generator modeling and internal fault analysis, and prototyping for multifunctional IED device dedicated to next-generation production. In this paper, over-excitation relaying algorithm is one of the main protection elements which have an important role in DGPS(Digital Generator Protection System), was proposed. This paper first briefly introduces a principles of over-excitation and DFT-based gain compensation algorithm was adopted for the frequency measurement. Subsequently, protection scheme of over-excitation was presented. The 765[kV] modeling data of South Korea using EMTP-RV was used for simulations. The simulation result of over-excitation relaying are also provided. [Copyright &y& Elsevier]

Abstract: This paper describes modeling and testing of a digital distance relay for transmission line protection using MATLAB/SIMULINK. ATP is used for detailed modeling of a power system network and fault simulation. SIMULINK is used to implement multi-resolution morphological gradient (MMG) relaying algorithm. MMG modeling is an interactive simulation environment for relaying algorithm design and evaluation. The basic principles of MMG relaying algorithm and some related algorithms such as tripping and fault location scheme are also described in this paper. Test results show that MMG relaying algorithm can detect and define fault location accurately within 1 milli-second. [Copyright &y& Elsevier]