A customised alternator at a high humidity, sand-laden location for demanding applications.
When Dubai-based Precision Industries (PI) won a bid for a very high capacity – 3,000kVA (Medium Voltage 3.3 KV) – generating set for a diversified and integrated group of energy companies in Abu Dhabi, it did not have to look far for the perfect alternator.
As a leading manufacturer of diesel power generating sets, PI has been working with Nidec Leroy-Somer as an OEM for other projects and knew it could rely on the company to supply the required alternator.
The project site – an onshore oil & gas installation – located in Abu Dhabi, UAE, has an ambient temperature range of up to 55°C and high humidity above than 95%, and is also marred by sandstorms. The requirement was for three customized generating sets of varying power capacity with tight delivery schedules.
Requirement For The Generating Set
The power generation requirement for the largest of these three units is 3,000kVA Prime rated generating set with 10% over loading – a 3,300V, 50Hz, IP55 alternator with a matching prime mover mounted in a totally enclosed, within customized heavy-duty enclosure (IP55). The current and voltage transformers used in this generator are equipped with highly advanced protection including differential protection (Class PX), restricted earth fault protection and short circuit protection, advanced digital AVR, customised terminal boxes to accommodate oversized armoured power cables.
The Alternator
Engineers at Nidec Leroy-Somer studied the requisition for the customised alternator: LSA 56 BL75/4p 3000KVA 3,3KV 50Hz Class H/B @ 55°C IP55 CACA totally enclosed machine with very special options. After detailed deliberation with PI and the end user, the team finalised the design. Once built, the alternator was subjected to the factory acceptance test at the Nidec Leroy-Somer works in France, on a special test platform, where it is subjected to a closed loop test at full load. The acceptance test was witnessed by customer representatives and other parties. The alternator was then shipped to UAE for the assembly of the generating set.
“This alternator is not something that many companies can deliver. We are proud that we are among the few companies that can meet such stringent specifications for an alternator. This also applies to Precision Industries, who then took over the job and put a lot of effort into integrating the alternator in the generator set. There is a huge amount of engineering that has gone into this project”. says Nawar Shubbar of Nidec Leroy-Somer.
The Generating Set
Precision Industries went through a complete process for project management that includes engine sizing and selection, alternator sizing, cooling system, containerisation, fire detection and suppression and complete integration of control and protection systems.
The engine is equipped with after-treatment for emission control with selective catalytic reduction (SCR) system – an advanced active emissions control technology – as the customer insisted on emission control in view of environmental concerns.
The fully welded, totally enclosed drop over type enclosure – rated IP 55 on standby and IP 44 in operation condition – with dimensions (LxWxH) 16m x 4m x 4m has been designed and fabricated in-
House By PI In UAE
The fire detection and suppression system are IG-541 inert gas protection system, which is a completely autonomous system without human intervention. Complete genset control and protection system with a local control panel located in the generator unit and a remote-control panel in the sub-station with an interface between the two, with connectivity with the SCADA system of the site, was manufactured in-house by PI. This system includes high-end parameters for control, complex operation philosophy based on site requirement, High-end protections with redundant serial communication, and complete controls over the generator unit.
“Precision Industries is known for high-end engineering capabilities. This is a generator set with a very high-power rating – 3000 kVA – equipped with a remote radiator and many other special features like the fire detection and suppression system as well as emissions control technology. We are pleased and proud to be working with Precision Industries, the only Emirati company, and for us, a local partner in this highly specialised field of generating sets. It is very important for us to support UAE enterprises in their plans to localise the industry and transfer the knowhow,” concludes Shubbar.