Summary: 
LIPTÁK, M., HRABOVCOVÁ, V., RAFAJDUS, P., ZIGMUND, B.:
Switched Reluctance Machine with Asymmetric Power
Converter in Generating Mode [full paper]
Switched reluctance (SR) machine has various desirable features, which
comes from its simple construction. They are the wide speed range, high
temperature operation and small moment of inertia. But without any
precise control technique no from these advantages could be utilised. SR
machine in generating mode also starts to be used and its control
technique can be even simpler than in motoring mode. In this paper a
drive with a small 6/4 SR machine with an asymmetric halfbridge power
converter produced as a motor, will be changed to generator. To obtain
this the control technique based on DSP as well as the drive setup will
be modified. The appropriate control technique for obtaining generating
mode will be designed and implemented for SR machine control. Generator
operation will be tested by various load and speed conditions.
Simulation results will be done for the purpose of comparing with those
measured.

JOUTSENSALO, J., GOMZIKOV, O., LUOSTARINEN, K.,
HÄMÄLÄINEN, T.:
Delay Minimization and Pricing Method for the Network
Services [full paper]
This paper proposes a scheduling model for ensuring delay as a Quality
of Service requirement in the communications network. Different delays
are allocated for different pricing classes, say gold, silver, and
bronze classes. Our purpose is to minimize weighted mean delay for
connections, where weights are the pricing factors of different classes.
An adaptive and optimal solution is derived for weights of the
scheduler. Simulations show that in addition to the mean delay
minimization, the revenue of the service provider is also maximized in
the linear pricing scenario. In addition, adaptive updating rule is
simple to implement, since it converges fast. Our scenario is
independent on the statistical assumptions, and therefore it is robust
against possible erroneous estimates of the customers' behavior.

BENDAOUD, A., SAYAH, H., MEDLES, K., MASSOUM, A.,
BRAHAMI, M.:
Measurement Frequency Influence on the Interference
Disturbances near the Extra High Voltage Lines [full paper]
The principal objective of this paper is to present a determination
calculation program of the exact profile of the level of radionoise of
existing lines E.H.V and on project according to the frequency. The
method used for the determination of the disturbing field is an
analytical method based on the theory of the modal propagation. We
present a calculation program based on MATLAB with examples of real
lines.

TOUFOUTI, R., MEZIANE, S., BENALLA, H.:
Direct Torque Control Strategy of Induction Motors [full paper]
Direct Torque Control of inverterfed Induction Machine allows high dynamic performance by means of very simple control schemes. In this paper various direct torque control methodologies as conventional DTC (C_DTC), modified DTC (M_DTC) and twelve sectors (12_DTC) have been analysed and compared in order to evaluate the influence of the motor operating condition on steady state performances. A particular emphasis on stator flux trajectory, torque ripple and stator current distortion has been made. Simulation results show the effectiveness of the proposed methods.

RAIČEVIĆ, N., ALEKSIĆ, S.:
Electric Field Regulation at the Cable Accessories Using One New Numerical Approach [full paper]
The problem of electric field grading in cable components, having both theoretical and technological implications, can be framed in more general topic of field control in HV equipment. A solution may be obtained by two possible approaches: using geometric field control [11, 13, 14, 15, 17, 18], in which the field distribution depends on the arrangement of main and auxiliary electrodes or using resistivecapacitive (RC) field control [2, 4, 6, 10, 12 ], where the field distribution relies mainly on the electrical characteristics of stress grading materials.
The above considerations are applicable to a wide class of MV and HV electrical devices such as insulators, bushings, spacers, voltage deviders, cable accessories (joints and terminations), etc. In the following, paper attention will be focused on the cable terminations and joints.
At the places of cable connections and endings exterior cover is removed, and the radial character of electric field is disturbed. Because of high voltage, the inhomogeneous electric field exists on those parts of the cable, having the highest intensity at the ends of the covers, or screen. Cable joints and terminations represent the weakest part of a HV cable power line because of the electric field enhancement at the edge of the truncated conductors and dielectrics.
The results for electric field and potential distribution at the coaxial cable terminations and joints, having exponential or ellipsoidal form, obtained by the Equivalent electrodes method (EEM), are presented in this paper. The EEM and Finite elements method (FEM) are compared. Equivalent electrodes (EE) are appointed on the end of coaxial cable, where the edge effect exists. At the great distance from terminations and joints, inside the cable, it may be considered that the field is approximately homogeneous and the charge distribution is continuous. At the cable splice, it is possible to solve the problem (electric field and electric potential distribution) as superposition of two components: the first one originates from continuous distribution of the electrical charge, and the second one from equivalent electrodes.

ABID, M., AISSAOUI, A. G., RAMDANI, Y., ZEBLAH, A. K.:
Sliding Mode Speed and Flux Control of FieldOriented
Induction Machine [full paper]
In this
paper, we propose a sliding mode technique to control the fieldoriented
induction machine. Our aim is to make the speed and the flux control
robust to parameter variations. The variation of motor parameters during
operation degrades the performance of the controllers. The use of the
nonlinear sliding mode method provides very good performance for motor
operation and robustness of the control law despite the
external/internal perturbations. The chattering effects is eliminated by
a particular function "sat" that presents a serious problem to
applications of variable structure systems. Simulation results are given
to highlight the performance of the proposed control technique under
load disturbances and parameter uncertainties.

DELLA KRACHAI, M., MIDOUN, A.:
High Efficiency Maximum Power Point Tracking Control in
PhotovoltaicGrid Connected Plants [full paper]
This paper presents a high performance tracking of maximum power
delivered from photovoltaic generators using adaptive neural fuzzy
inference systems ANFIS. The nonprecise and uncertain behaviour of the
climate require stochastic modeling. This hard and hazardous task
consumes more computation. Fuzzy logic is the powerful tool for modeling
uncertainty and approximate reasoning, however, the presence of expert
is the most important part of the design. Expertless design requires
data which must cover all the possibilities of operation. Neural
networks are the best learning machines in the field. ANFIS combines the
advantages of fuzzy logic and neural networks in one package and gives
an optimized fuzzy inference system embedding the whole knowledge of the
system behaviour (tracking operation). Hysteresis current controller is
implemented in order to shape the current to be interfaced to the public
grid.
Simulation results carried out from MATLAB demonstrate the success of
the technique giving thus high efficiency of the proposed controller.

BOUSSERHANE, I. K., HAZZAB, A., RAHLI, M., MAZARI, B.
KAMLI, M.:
Optimal Fuzzy Gains Scheduling of PI Controller for
Induction Motor Speed Control [full paper]
In this paper, an optimal fuzzy gain scheduling of PI controller is
adopted to speed control of an induction motor. First, a designed fuzzy
gain scheduling of PI controller is investigated, in which fuzzy rules
are utilized online to adapt the PI controller parameters based on the
error and its first time derivative. However, the major disadvantage of
the fuzzy logic control is the lack of design techniques, for this
purpose we propose an optimization technique of the fuzzy logic adapter
parameters using genetic algorithm. The effectiveness of the complete
proposed control scheme is verified by numerical simulation. The
numerical validation results of the proposed scheme have presented good
performances compared to the fuzzy controller which have parameters
chosen by the human operator.

LAOUER, M., ALLALI, A., HACHEMI, K., BOUZEBOUDJA, H.,
CHAKER, A.:
Study of the Load Flow in Electrical Supply Networks
AC/DC [full paper]
The study of the Power
flow is very significant, because it makes it possible to provide
information of large importance; in order to better plan, to control and
ensure finally the correct operation of the electrical supply networks.
In our article, we present a method of calculation of the flow of powers
in a mixed electrical supply network in high voltage (AC/DC). This
method called also method SPI: (Substituted Power Injection) makes a
small modification to the level of the bus of connection DC. The
calculation of the active and reactive powers at the final bus of system
ACDC, are obtained by the subtraction of the powers of the converters
and those which are specified with the bus of connection DC. This method
will be applied to the 14 bus networks.

