Generator

The Simple rule which normally dominates the selection of vector group of a transformer is the network where it is to be installed. Normally there are three networks: Generation, Transmission and Distribution. The inherent advantage of the D connection is prevention of zero sequence and harmonics to enter in the network.

Now starting from the Generation. The generators are connected in the Y. Now from the Generators the Unit Transformers are used to transmit the power. The prefera ...

The real reason behind the choice of 11, 22, 33, 66 and 132kV levels is not clear from the responses to date and it may have passes into history unknown. Most likely, it was a decision arising from a standards committee and it may be an optimum transformation ratio chosen to minimize total losses. Someone still alive may yet know the reason. Then again, it may have a legacy resembling that of the standard rail gauge.

These numbers were chosen arbitrarily in the past and have actual ...

In hundreds MW plant we are using static excitation system, but it require more maintenance than brushless. Why not we are going for brushless system? What is the reason behind this?

As far as I know, the increased maintenance requirement is associated with the slip rings and brushes. It is not so easy to replace a static excitation system with a brushless system, as you'd have to change things in the machine rotor and shaft (remove the connections to the brushes and slip rings, ad ...

The calculations are no different than those for determining how to start a large synchronous motor, it all depends upon the type of generator and how big it is relative to the system that you are connecting it to. Take a look at the SLD (Single Line Diagram) and get the GSU (Generator Step Up) transformer rating and impedance, transmission line impedance to the grid, as well as any information that you have on the generator. Then you can determine how much the voltage will dip if the generat ...

YES, but it can only be done long term with an electric motor that is designed to also run as a generator and if the generator will be paralleled with other generation the motor will need to be a synchronous motor.

I served in the US Navy on a submarine as an electrician nuclear qualified. My electrical plant includes 2 - 500 KW motor generators. When the AC end was operating as an AC motor the DC end was a DC generator that supplied power to the sub's battery, reverse current and ...

Many installation sites need electric power for construction activities. When the site not large all construction equipments are powered with single phase supply. Such single phase DG sets may be available. Site gets single phase supply from utilities for construction. A new construction equipment requires a three phase supply. We have three DG sets of small capacities say 10 KVA etc. With this single phase DG sets can we provide supply to a three phase construction gadget?

Yes, ho ...

You can find a simple explanation of what an induction generator can do. It is totally self-synchronizing with the grid it is feeding power into. It stays in sync and delivers energy as long as it is driven at an rpm higher than its synchronous speed. If it is feeding a 50 Hz power supply it must be driven 2% to 5% above ts sync speed. Sync speed is 120 X frequency / number of poles thus a 4 pole machine ...

Required or not, ground ring provides a better (lower impedance) grounding system. It really depends on what the specifications of the project call for. Here, ground rings are typically only used for sensitive electrical equipment installations - such as computer/data/network server rooms. For industrial/motor control/general light and power applications, a properly sized equipment grounding conductor (green wire), sized in relationship to the overcurrent protective device, is installed in th ...

One of our clients asked is it possible to start a pump motor by directly connected power cable to diesel generator set without any means (breaker)? The diesel generator set is 1250kW and the motor is 630kW.

Initially I thought what an idiot and then stopped to pause. What are the design requirements and are you retro-fitting the pump to an existing diesel generator. The process of soft starting the pump using the DG should be able to be done if you are working from first principle ...