Cogeneration or combined heat and power (CHP) applications where heat and power is generated simultaneously, have unique requirements. The reliability of our alternators and the built in feature rich design means products can be trusted for continuous operation.
Our extensive experience in the power generation industry as well as our diligent studies and thorough research has led to the development of our alternators range. Mecc Alte has many alternators in proven CHP installations across the globe.
Mecc Alte product features are designed into the alternator. Peak efficiency is typically at 80% load coinciding with class B temperature rise, typically required in such applications. This gives the system optimum efficiency, and economic sizing.
Self-regulation is obtained through a digital electronic regulator that is fed by an auxiliary winding. We guarantee an almost constant supply from the generator – under any possible operating condition. A rotating inductor is fitted with a damper cage.
The windings have a 2/3 pitch in order to reduce the harmonic content of voltage.
The entire series is manufactured according to, and complies with, the most common specifications such as CEI 2-3, IEC 34-1, EN 60034-1, VDE 0530, BS 4999-5000, CAN/ CSA-C22.2 No14-95- No100-95.
1. Low reactance stator
2. DSR/DER – digital regulator with multiple settings and real-time memory, logging any faults in operation
3. Single regulator can be used throughout the range
4. Innovative design with low weight and compact size
5. Easy access to check diodes
6. MAUX system auxiliary winding as standard providing >300% short circuit current. PMG optional on 180kVA and above
7. Rugged design (withstands up to 7G)
8. FEM-assisted design of the magnetic circuit for optimum performance and maximum efficiency
9. MAUX system offers dedicated and isolated power supply to the regulator
10. 2/3rds pitch winding to eliminate harmonics
11. Flexible design accommodates many winding voltages and many coupling types
The robust mechanical structure permits easy access to the connections and components during routine maintenance check-ups.
The materials used in the mechanical structure are FEP12 steel for the frame, C45 steel for the shaft and cast iron for the end-brackets.
The standard degree of alternator protection is IP23.
Other higher degrees of protection, such as IP45 and IP55, are available on request.
INSULATION AND IMPREGNATION
Insulation is of Class H standard. Impregnation is made with premium tropicalised epoxy resins by dipping and dripping. High voltage parts are impregnated by vacuum, so the insulation level is always very good. In the high-power models, the stator windings undergo a second insulation process. GREY protection is standard on larger power machines where an additional layer of grey EG43 varnish is applied on the main and exciter stator to give enhanced protection. Other special treatments for particular environmental conditions are available on request; TOTAL protection and TOTAL+ protection which use a black flexible compound to give the ultimate winding treatment. This black compound system assures superior performances in harsh or demanding environments. (Please refer to Insulation Protection Systems Handbook for more information.)
The voltage accuracy is +/-0.5% (DER) in static condition, with any power factor and with speed variation between 5% and +30% with reference to the rated speed.
The voltage can be regulated by the volt potentiometer on the electronic regulator or by an external control device, commonly used by the genset industry to govern the genset. With our digital AVRs, it is possible to control and adjust the range of voltage, electrically through our compatibility software. In addition, password protection can be set to avoid any possible trouble that can be made by less skilled personnel.
TRANSIENT VOLTAGE AND RESPONSE TIMES
At a full load, no load and at constant speed there is a transient voltage variation lower than 15% of the rated power. In such conditions, the 3% voltage resetting will occur in 0.2 seconds for powers up to 300kVA, while for higher powers it will occur in 0.3 seconds. (Refer to the User Manual for more detail).
The alternators with damper cage (>7.8kVA) can function in parallel among themselves, not withstanding the type of alternator and/or in parallel with the mains provided they are equipped with a droop transformer. This device is available upon request for the alternators up to type 38, while the alternators with a higher power are equipped with this as standard equipment. In case of parallel with the mains, we offer the P.F.R. 96/2 electronic device which controls the alternator’s reactive current and/or power factor of the alternator.
The permissible overloads are of 300% for 20 seconds, of 50% for 2 minutes and of 10% for 1 hour every 6 hours of operation.
RADIO INTERFERENCE SUPPRESSION
The standard generators comply with the specification VDE 0875, degree “K” and the basic safety requirements of the European regulation on electromagnetic compatibility. By applying the European standards EN 60034-1, we comply with the above mentioned regulation. Upon request, we are available to study and produce EMC filters according to more restrictive specifications.
MAUX (Mecc Alte Auxiliary)
PMG (PERMANENT MAGNET GENERATOR)
PMG (Permanent Magnet Generator + Auxiliary)
FOR MORE TRADITIONAL USERS OUTSIDE OF THE MAUX SYSTEM WE CAN OFFER A PERMANENT MAGNET GENERATOR.
This is available on ECO38 ECO40, ECO43 and ECO46 series:
(180 – 2750kVA) series as a factory-fitted option. In addition on the ECO40, ECO43 and ECO46 series
(400 – 2750kVA) this option can be retrofitted allowing our customers to keep minimal stock.