ÎN RELEE DIGITALE DE PROTECȚIE
The accuracy and the speed of decision making of the protection
relays are very important to maintain the continuity of supply to the electrical
power system during different disturbances.
A/D Converter shares an important role in achieving that requirement,
so that all types of A/D Converters used in power relaying applications will be
discussed in this paper and some recommendations will be offered depending
on that discussion.
Acuratețea și viteza de luare a deciziilor a releelor de protecție sunt
foarte importante pentru a menține continuitatea aprovizionării sistemului de
energie electrică în timpul diferitelor perturbații.
A/D convertorul analog-digital are un rol important în realizarea acestei
cerințe, astfel încât toate tipurile de convertoare A/D utilizate în transmiterea
aplicațiilor de putere vor fi discutate în această lucrare și unele recomandări vor
fi oferite în funcție de această discuție.
Keywords: digital relay, digital signal processing, electrical power
system, digitization, quantization, sampling
Cuvinte cheie: releu digital, procesare a semnalului digital, sisteme de
energie electrică, digitizare, cuantizare, eșantionare
CALITATEA ENERGIEI ELECTRICE
Power quality problems can cause processes and equipment to malfunction or shut down. And the consequences can range from excessive energy costs to complete work stoppage. Obviously, power quality is critical. There are many ways in which a power feed can be poor quality, and so no single figure can completely quantify the quality of a power feed. In this paper we are going to present all definitions, classifications and problems related to power quality. Finally, we have done comparison between the practical measurements and standards related to power quality.
Keywords: power quality, standards, electrical power system, electric power grids
Cuvinte cheie: calitate de putere, standarde, sisteme de energie electrică, rețele de energie electrică
MONITORING SYSTEMS IN HAZARDOUS CONDITIONS OF HYDROELECTRIC PUMPED STORAGE (CHEAP)
The primary purpose of modern automation purposes of modern automatic control systems of hydroelectric plants are:
– Automatic adjustment of speed (frequency) and/or power energy group known as Automatic speed control systems (SRAV)
– Automatic adjustment of the voltage generator known as automatic control systems excitation (SRAE)
– Adjust the water level in the reservoir and swirled flow, depending on the spatial requirements
– Protection hydropower group to failures, defects or on the electric or hydraulic side.
Keywords: automatic control systems, automatic adjustment of speed, generator voltage
Cuvinte cheie: sistemelor de conducere automată, reglarea automată a turaţiei, tensiunii generatorului
IN MEMORIAM – DISTINGUISHED PROFESSOR EMERITUS DR.ING. MIRCEA DIMITRIE CAZACU
Were presented some parts of the work that has been Professor Emeritus, scientist , engineer – musician Mircea Dimitrie CAZACU whom we maintain an eternal, beautiful memory. He died at the age of 86 years, is in full swing.
A NEW GLOBAL CONCEPT FOR THE INTEGRATED
SYSTEM OF SERVICES DEDICATED TO
THE ASSEMBLY OF STATIONS, SUBSTATIONS
AND ELECTRIC POWER GRID
– CSRE, SEEN AS A WHOLE –
The proposed work has, as a primary aim, the analysis of internal
technologic consumption CPT given by the inner network of internal consumers
– so called the ancillaries – sustaining each individual component from the
general assembly of CSRE – stations, substations, and electric power grid to run
properly with their sensible direct influence over the generating and transporting
at the effective cost of electricity.
This first part of this study, quite a classical one – standing also as
basic support for our courses, gives also new insights for the students
regarding each component from the CSRE family: complex phenomena onto
the power contour for every independent component running stable for its
own, regarding the power stations, substations and the interconnecting
transporting networks – all in order that every individual component is to give
its own contribution for stable operation, focusing onto the last goal – toward
minimization this overall CPT.
The second important objective is to show the enlisted so-called
external services performed by every basic elements from the CSRE family,
to sustain the normal-stable running in harmony for the entire global National
Power System called SEN, as a whole. The external services offered by
every component from CSRE toward the general assembly of SEN are to
define today one modern basic pack of functions, as a new global vision,
toward stability at reduced cost.
This pack of external services has a dynamic character, being one
continue expanding and sustained process of up-grading within its specific
frame and limits of dedicated applications: from each component to the
whole assembly of the National Power Grid called SEN, through this
balanced package of so-called system’s external services.
The third objective is to add some more clear understanding to the
reader’s for this genuine overall academic concept regarding the family of
pertinent services – both internal and external – which should be seen as
one reliable and basic starting point for every TSO-dispatching entity,
conducting to one improved running stability for the Electric power system,
national scale, called SEN.
This frame of discussion seen furthermore at European coverage –
called at UE scale – as ENTSO-E, the study through this original point of view
is to gain one overall extension, seen in future – as tending to planetary
Keywords: stations, substations, and electric power grid – CSRE,
national power system-SEN, European Power System-ENTSO-E, internal
system of services-SSI, dedicated for every components from SEN, external
system of services-SSE, dedicated to the SEN incorporated into ENTSO-E
Cuvinte cheie: centrale, stații și rețele electrice-CSRE, sistem
energetic național-SEN, sistem energetic European-ENTSO-E, sistemul
serviciilor interne-SSI, individual dedicat componentelor SEN, sistemul
serviciilor externe-SSE, dedicate ansamblului SEN, încorporat ENTSO-E
IMPACT OF PUMPED STORAGE HYDROPOWER PLANTS
(CHEAP) ON CRITICAL INFRASTRUCTURE
Critical infrastructure protection is an area that requires very well
investigated, monitored, analysed, evaluated, and improved forecast.
Management, critical infrastructure „should be ensured through a
rigorous and effective management of risk and vulnerability prevention and not
by an action plan for removing the effects of a possible disruption to operation.
Effective management of critical infrastructure has the fundamental
safety culture in the public, professionals, managers, politicians and so on,
achieving national partnership between the public and private sectors to ensure
an acceptable landing critical infrastructure security, a specific legal system of
critical infrastructure protection, in line with European and international law.
Keywords: infrastructure, infrastructure, evaluation criteria, Tarniţa-
Cuvinte cheie: infrastructură, ansamblu de infrastructuri, criterii de
evaluare, acumulare prin pompare Tarniţa-Lăpuşteşti
PRINCIPLES OF MODERN AUTOMATION REGARDING
SMALL HYDRO POWER UNITS
Small Hydro Power Plants – SHPP are considered among the
simplest power energy conversion installations in relation with their
technological process; however, by taking into account the risks of an
unbalanced operation and the ambition to be remote completely controlled
without permanent operational personnel, the specific required system of
automation herewith implemented, has to be one with higher performances,
Cuvinte cheie: scheme electrice de conexiuni, microhidrocentrale
electrice MHC, servicii proprii, acŃionări variabile, economie de energie,
convertoare de frecvenŃă, soft-startere
THE ASSESSMENT OF A PROFITABLE INVESTMENT:
SMALL HYDRO POWER PLANT SHPP
CIUREL– LACUL MORII
This study presents the huge advantages balanced by some
drawbacks when the selected site for a new SHPP belongs to a particular
frame, already in partial operation. The dam is finished, also the hydro power
conduit is quite done so, and the SHPP is just waiting to be installed, in spite of
the well-known consistent specific expenses for such particular investment into
one HPP of small rated power capacity. The practical exercise regarding such
particular investment clearly reveals – at a glance – its profitable character.
Keywords: dam, hydropower AHE, micro hydro central MHC, hydro
HA, TH hydraulic turbine, hydro asynchronous/synchronization
Cuvinte cheie: baraj, amenajare hidroenergetică AHE, microhidro
centrală MHC, hidroagregat HA, turbină hidraulică TH, hidrogenerator asincron/
OVERVIEW REGARDING DRAFTING AND IMPLEMENTATION
OF THE PHOTOVOLTAIC POWER PLANTS INTO ROMANIA
In this paper we do present some first and pertinent aspects regarding
the implementation also into Romania these new power source based on
renewable energy, among is to stand the huge amount of solar energy – directly
converted into electricity. Of coarse, as a beginning period, a lot of these
aspects related within this kind of energy conversion are regarded as difficulties
and, our paper is trying to underline only the main aspects encountered by both
– designers and engineers, directly involved into erection on sites.
Cuvinte cheie: string, invertor, tensiune, fotovoltaic, energie
Keywords: string, invertor, voltage, photovoltaic power plant PPP
H.P.P. EXTENDED OPERATIONAL CAPACITIVE REGIME
WITHIN THE CONTRIBUTION OF ONE DIGITAL A.V.R.
The paper presents some important aspects regarding the extended
capacitive field of operation for one Hydro Power Plant – HPP with the
contribution of a digital Automatic Voltage Regulator AVR. As we do know, the
capacitive regimes are more difficult to be operated for one remote HPP and,
from here, the AVR found to work properly could be considered to be the
proper chosen one. Among AVR chosen to control at the best such regimes,
devoted for special cases with remote HPP are preferred those of digital type.
The paper presents by comparison, two types of different AVRs at work – one of
old classic type SAREX 42 A vs. the newer digital one, of much more improved
performances, called type SRAT-N.
Cuvinte cheie: sistem de excitație SE, sistem de reglare automată a
tensiunii SRAT, hidrogenerator sincron HG, centrală hidroelectrică CHE
Keywords: system excitation SE, automatic voltage regulator AVR,
hydroelectric generator HG, hydroelectric power plant HPP
ONE INFORMATIC APPROACH TO DESCRIBE THE
PROCESS FROM ONE HPP WITH STORING FACILITIES
In the conditions of today world wide rising price for conventional fuels,
the renewables and especially those of hydro power domain are coming to play
one more important role at higher efficiency. The most complex hydro power
plant HPP having storing energy facilities is already planned in our country into
the forseen future; it will be at the level of 1.000 MW/400 kV as rated power and
transmission voltage with the expected commissioning term-by the year 2020.
Cuvinte cheie: centrale hidroelectrice cu acumulare prin pompaj
Keywords: central hydroelectric reservoir by pumping