The design principles of diesel generator includes: cooling system, lampstand, environmental protection equipment for diesel generators, diesel generator parallel system, flexible and reliable automatic switching system etc.
Now Starlight will share some attentions for diesel generator parallel system and installation.
1.The design of principles of diesel generator parallel system
The design of parallel optimization system for diesel generator sets adopts a parallel machine scheme with load distribution function for parallel machine monitoring system and parallel cabinet, it can be better to apply to large-scale parallel systems. We can accord to different requirement, for example, if apply to start-up of large power generator, the system can provide pre-start to meet the requirements. Aiming at the strong, weak and electromagnetic interference problems in parallel system, the design should use software filter and hardware filter to solve the problem. Adopt CAN bus methods to compare the digital quantities to achieve more effective active power allocation, this can avoid adverse effect to active power distribution by voltage loss in voltage load distributor.Aiming at different generator types to design and ensure reactive power distribution form. Aiming at the generator that uses AVR pressure regulating template, its reactive power distribution adopts software programming to increase voltage feedback to offset the adverse effects of temperature drift. In order to avoid impact on generator. In the parallel system, a zero power conversion design scheme is provided, that is, automatic synchronization between genset, zero power working for newly added genset, and then load transfer and average distribution are carried out smoothly according to the setting.
2.Attentions for parallel generator set:
(1) Before parallel genest, firstly must check whether the two genests meet follow requirements:
A.The RMS and waveform of generator voltage must be the same;
B.The phase of the voltage of the two generators is the same;
C.Two generators have the same frequency;
D.The phase sequence of the two generators is identical.
Only when meet the above four conditions and the parallel cabinet is used, the operation of diesel generating sets in parallel can be carried out.
(2) In addition to meeting the basic conditions for parallel generators, we also need to know about quasi-synchronous parallel method for generator sets, otherwise, will damage genest when doing parallel operation. Quasi-synchronous means accurate cycle. If use quasi-synchronous parallel method, the voltage of two generators must be the same, same frequency and same phase, this can be monitored by two voltmeters, two frequency meters and synchronous and non-synchronous indicator lights mounted on the synchronous disk to ensure the safe operation of generator sets..
When parallel diesel generator, it is not better to use manual parallel operation, because the success or failure of manual parallel depends on human experience, it is easy to cause safety accidents.
Generator should have installation conditions as follows:
Concrete foundation, intake louver, outlet louver, smoke exhaust outlet, smoke exhaust muffler, shock proof and expansion exhaust pipe installation location etc. And auxiliary equipment such as generator mailbox, battery, control screen, distribution cabinet should be near the generator equipment.
3.When install diesel generator, also need to attend something as follows:
A.All diesel generator has lampstand, in generally, adopt shock absorption measures on lampstand, the lampstand should be installed on concrete base;
B.The best way to install genset is to use concrete to place and fix generator set. It can make the genest run smoothly and reduce vibration. The bearing capacity of concrete foundation should be designed as 1.5 times of the genest's dead weight in order to support the weight of the whole generator set and the dynamic impact load caused by the unbalanced force during the operation of the generator; the subsoil under the concrete foundation must also have enough bearing strength to bear the weight of the genest and the concrete foundation.
C.When the base use concrete, must measure its levelness with a level ruler when install, to let generator set is on a same level. There should be a special shock pad or sole bolt between the genest and the foundation.
D.The place of installation should keep excellent ventilation, there should be enough air intake at the generator end and good air outlet at the diesel engine end. Air outlet area should be more than 1.5 times larger than water tank (radiator) area;
E.The place around installation should keep clean, to avoid placing something which can produce acidic, alkaline and other corrosive gases and vapors;
F.Housing of generator set must have reliable protective earthing, for generator that needs neutral point direct grounding, the neutral point must be grounded by professionals and equipped with lightning protection devices. It is strictly forbidden to use the grounding device of municipal electricity for direct grounding of neutral points;
G.The arrangement of diesel generating units should conform to the essentials of process flow;
H.Before planning, designing and installing the generator set room, should select and purchase diesel generating set and control panel, know about installation engineering requirements of use instructions which provided by manufacture, if the site conditions do not meet all the requirements for generator set installation or have any question, must contact the manufacture for sure answer.
After installed genest, should use it according to the use instructions, so that can keep genest a long life service.