· web viewpicture 8: series harmonic reactor of the lv antiresonance harmonic filter the...
TRANSCRIPT
ΤHE SCIENTIFIC ENERGY SAVING PROJECT OF SEMANIN FIBRAN SA, TERPNI SERRON, GREECE.
Α. FIBRAN INSULATION MATERIALS
FIBRAN (www.fibran.gr) was founded in 1974 and since 1995 it plays a leading role as a producer of insulation materials both in Greece and in Europe.
Today, FIBRAN has 6 production units, utilizing the latest technology for the manufacture of insulation products (Extruded Polysterene, Stonewool and Expanded Polysterene), as well as Gypsum Boards.
In Greece, in the industrial plant located in the Village of Terpni, Serres, FIBRAN produces - by two production lines GEO1 and GEO2- stonewool insulation products with the brand name FIBRANgeo and extruded polysterene products with the brand name FIBRANxps.
Picture 1: General plant view
The total installed electric power of GEO2 production line comes up to 7 MW. The grid is in 50Hz. The main load of the plant is the induction oven which fed by a Power Transformer of 4MVA at 21kV voltage level, while all the other loads are fed through a Transformer 21/0,4kV with rated power 2,5MVA. The average annual electricity cost of GEO2 production line is approximately 2.500.000 € in current prices.
1
Picture 2: GEO2 Production Line
Β. The scientific project of SEMAN SA
The project concerned the reduction of the current voltage harmonics, the improvement of motors’ and power transformers’ efficiency, the minimization of the reactive currents and the reduction of the consumed electrical energy in the inner of the plant’s electrical installation, as well.
In order to elaborate the scientific study for FIBRAN’s Electric Power Grid, the engineer’s staff of SEMAN SA performed measurements and recordings – of all the required electrical values – in each individual load of the installation (AC & DC motors, motors operating with Inverters, inductive furnaces, DC Converters, Star- Delta switches etc. both in Low and Medium Voltage).
2
Picture 1 : Laptops used for measurements and recordings
Measurements and recordings concerned the basic electric values (power, reactive power, voltage, current, frequency) as well as current & voltage harmonics (up to the 35th class) and transient phenomena.
Picture 2 : Measurements have been performed also in the core of the electrical installation next to the loads
Moreover the engineers’ staff of SEMAN SA proceeded to the collection of all the essential data that had to do with length and cross-sections of cables, number of cables headed together in canals, nominal values of motors, power transformers and many others also necessary for elaborating the scientific study for the energy saving project.
3
Picture 3 : Measurements with special power quality analyzer
Based on the above, the engineers of SEMAN SA were able to simulate the behavior of FIBRAN’s Electric Power Grid and detect all the problems that were causing bad quality of voltage and current, low electric loads and power transformers efficiency, harmonic resonances and multiple other energy losses.
The analysis of measurements and recordings showed that considerable harmonic sources existed inside FIBRAN’s Electric Network, producing harmonic currents and also considerable voltage harmonics.
Moreover, a number of energy saving scenarios, for the specific Electrical Power Grid – all based on the know-how of SEMAN SA – carried out by the use of simulations and finally the scientific study concluded 15 specialized interventions (please refer to pictures 6, 7, & 8 for low voltage loads and to pictures 9, 10 & 11 for medium voltage loads) that had been installed inside the Electric Power Network of FIBRAN.
More specific:
12 interventions installed in parallel at LV network of 400V 2 interventions installed in series at LV network of 400V 1 intervention installed in parallel at MV network of 21kV.
The total installed power of the interventions for the voltage-current quality improvement and energy saving project was 2 MVA.
4
It should be mentioned that the design of interventions took into consideration not only the interaction with other electric loads of the network, but also the resonance frequencies of the electric power cables of the grid.
The scientific project for energy saving and current - voltage quality improvement has been completed in October 2010.
Picture 6: Low Voltage (LV) Variable Antiresonance Harmonic Filter
5
Picture7: Low Voltage (LV) Variable Antiresonance Harmonic Filter
Picture 8: Series Harmonic Reactor of the LV Antiresonance Harmonic Filter
The customized interventions for voltage-current quality improvement are connected in parallel or in series to the electric loads and lead to harmonics absorption and their important reduction inside the electric installation of the
6
factory. Furthermore, resonance frequencies that could lead to dangerous tuning are being cut off. PLC with special design from SEMANS’s engineers, based on the results of the scientific study, control the dynamic operation of each intervention according to the fluctuations of the electric load and ensure the cutting of all dangerous interactions between the loads.
Picture 9: Medium Voltage (MV) Antiresonance Harmonic Filter
Picture 4 0 : Detail of Medium Voltage (MV) Antiresonance Harmonic Filter
7
Picture 11: Detail of the MV Antiresonance Harmonic Filter
C. Results – Benefits
After the completion of the project, measurements and recordings were performed that demonstrated significant reductions in currents, improvement of voltage levels, important reduction of current voltage harmonics, and almost annihilation of the requested reactive power with power factors at central and local level in the limits of optimum one (1).
Table 1 presents the results.
Table 1. Synoptic Results of Power Quality Improvement and Saving Project accomplished for GEO2 production line of FIBRAN SA
Value ResultsGuaranteed saving according to the contract (%) -4,47%Saving achieved (%)(according also to the Reference Letter by FIBRAN) -7,84%
Guaranteed Pay Back Period of the project (months)
29,4
Real Pay Back Period of the project (months) 17
Annual Money Saving(€) 196.000,00 €
Furthermore, in the inner of the plant’s electrical installation and in depth of time after the completion of the Optimum Energy Management –Electric Energy Saving Project, the following were noticed:
8
1. Minimization of the problems created in the motors, such as windings burn.2. Reduction of the damages in contactors, fuses and switches and of the
memory losses in PLC programs, due to the optimal power quality.3. Discharge of the electrical equipment (with expecting increase of its
durability).4. Increase of the electrical installation reserve, due to great current reductions
in its inside. New loads might be supplied by the existing equipment of electrical panels, cables. etc, without any additions in electrical material and further expenses.
9