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Is it possible to synchronise two generators with no common electrical load to be exactly out of phase?
No, is it not permissible to synchronise two generators with no common electrical load to be exactly out of phase. Doing so would represent a double short circuit to both generators, and possible destruction of both generators. Whether it is possible or not depends on the design of the synchronizing circuit and/or the stupidity of the operator.
When you need to install permanent load bank for generators?
A load bank might be permanently installed when the generator has a large generating capacity and the connected load is very light.
Is this normal during a parallel of two generators where lead generator is higher in both load ampere and reactive power than the lag generator but with the same frequency same kilowatt load?
No it is not normal. Ideally both the generators share the load equally provided both generator ratings and other parameters are same.
What is the difference between an inductive and a capacitive load?
Resistance load it means there is passive load to impede current flow. Inductive load means there is a coil as a load while still a passive it has its own characteristics which differs from a resistive load which is linear while inductive is not linear load
What are the condition for parallel operation of the generators?
Parallel Operation of DC Generators: In a dc power plant, power is usually supplied from several generators of small ratings connected in parallel instead of from one large generator. This is due to the following reasons: (i) Continuity of service: If a single large generator is used in the power plant, then in case of its breakdown, the whole plant will be shut down. However, if power is supplied from a number of small units operating in parallel, then in case of failure of one unit, the continuity of supply can be maintained by other healthy units. (ii) Efficiency: Generators run most efficiently when loaded to their rated capacity. Therefore, when load demand on power plant decreases, one or more generators can be shut down and the remaining units can be efficiently loaded. (iii) Maintenance and repair: Generators generally require routinemaintenance and repair. Therefore, if generators are operated in parallel, the routine or emergency operations can be performed by isolating the affected generator while load is being supplied by other units. This leads to both safety and economy. (iv) Increasing plant capacity: In the modern world of increasing population, the use of electricity is continuously increasing. When added capacity is required, the new unit can be simply paralleled with the old units. (v) Non-availability of single large unit: In many situations, a single unit of desired large capacity may not be available. In that case a number of smaller units can be operated in parallel to meet the load requirement. Generally a single large unit is more expensive. Connecting Shunt Generators in Parallel: The generators in a power plant are connected in parallel through bus-bars. The bus-bars are heavy thick copper bars and they act as +ve and -ve terminals. The positive terminals of the generators are .connected to the +ve side of bus-bars and negative terminals to the negative side of bus-bars. Fig. (1) shows shunt generator 1 connected to the bus-bars and supplying load. When the load on the power plant increases beyond the capacity of this generator, the second shunt generator 2 is connected in parallel with the first to meet the increased load demand. The procedure for paralleling generator 2 with generator 1 is as under: (i) The prime mover of generator 2 is brought up to the rated speed. Now switch S4 in the field circuit of the generator 2 is closed. (ii) Next circuit breaker CB-2 is closed and the excitation of generator 2 is adjusted till it generates voltage equal to the bus-bars voltage. This is indicated by voltmeter V2. (iii) Now the generator 2 is ready to be paralleled with generator 1. The main switch S3 is closed, thus putting generator 2 in parallel with 51 generator 1. Note that generator 2 is not supplying any load because its generated emf is equal to bus-bars voltage. The generator is said to be "floating" (i.e. not supplying any load) on the bus-bars. Figure(1) (iv) If generator 2 is to deliver any current, then its generated voltage E should be greater than the bus-bars voltage V. In that case, current supplied by it is I = (E - V)/Ra where Ra is the resistance of the armature circuit. By increasing the field current (and hence induced emf E), the generator 2 can be made to supply proper amount of load. (v) The load may be shifted from one shunt generator to another merely by adjusting the field excitation. Thus if generator 1 is to be shut down, the whole load can be shifted onto generator 2 provided it has the capacity to supply that load. In that case, reduce the current supplied by generator 1 to zero (This will be indicated by ammeter A1) open C.B.-1 and then open the main switch S1. Load Sharing: The load sharing between shunt generators in parallel can be easily regulated because of their drooping characteristics. The load may be shifted from one generator to another merely by adjusting the field excitation. Let us discuss the load sharing of two generators which have unequal no-load voltages. Let E1, E2 = no-load voltages of the two generators R1, R2 = their armature resistances V = common terminal voltage (Bus-bars voltage). Then 1 1 1 R I E V   and 2 2 2 R I E V   Thus current output of the generators depends upon the values of E1 and E2. These values may be changed by field rheostats. The common terminal voltage (or bus-bars voltage) will depend upon (i) the emfs of individual generators and (ii) the total load current supplied. It is generally desired to keep the busbars voltage constant. This can be 52 achieved by adjusting the field excitations of the generators operating in parallel. Compound Generators in Parallel: Under-compounded generators also operate satisfactorily in parallel but over compounded generators will not operate satisfactorily unless their series fields are paralleled. This is achieved by connecting two negative brushes together as shown in Fig. (2) (i). The conductor used to connect these brushes is generally called equalizer bar. Suppose that an attempt is made to operate the two generators in parallel without an equalizer bar. If, for any reason, the current supplied by generator 1 increases slightly, the current in its series field will increase and raise the generated voltage. This will cause generator 1 to take more load. Since total load supplied to the system is constant, the current in generator 2 must decrease and as a result its series field is weakened. Since this effect is cumulative, the generator 1 will take the entire load and drive generator 2 as a motor. After machine 2 changes from a generator to a motor, the current in the shunt field will remain in the same direction, but the current in the armature and series field will reverse. Thus the magnetizing action, of the series field opposes that of the shunt field. As the current taken by the machine 2 increases, the demagnetizing action of series field becomes greater and the resultant field becomes weaker. The resultant field will finally become zero and at that time machine 2 will be short circuited machine 1, opening the breaker of either or both machines. Figure (2) When the equalizer bar is used, a stabilizing action exists and neither machine tends to take all the load. To consider this, suppose that current delivered by generator 1 increases. The increased current will not only pass through the series field of generator 1 but also through the equalizer bar and series field of generator 2. Therefore, the voltage of both the machines increases and the generator 2 will take a part of the load.
Are Yamaha generators good quality?
Yamaha itself is a great brand and when it come to generators they have the best selections. These generators are heavy duty workers that can stand the load of heavy appliances.
Why droop ct used in generators?
Droop CT is used to control load sharing of the reactive power b/w paralleled generators.
Is it possible to synchronise two generators with no common electrical load to be exactly out of phase?
No, is it not permissible to synchronise two generators with no common electrical load to be exactly out of phase. Doing so would represent a double short circuit to both generators, and possible destruction of both generators. Whether it is possible or not depends on the design of the synchronizing circuit and/or the stupidity of the operator.
Does power load affect fuel consumption of portable generators?
Yes, the more load that is placed on the generator the more fuel it will use.
What is meant by load in diesel generators?
Any device that uses the generator to supply its operating voltage is electrically classed as a generator load.
When you need to install permanent load bank for generators?
A load bank might be permanently installed when the generator has a large generating capacity and the connected load is very light.
Why load shedding panels are used in substation?
If you have many Gas turbine Generators working on parallel, if any fault happened in one generator ( so this generator is no longer feeding the load ) load shedding panels will disconnect a group of predetermined Less important loads to help the working generators in the additional load (which may come after fault of the mentioned generator ).
Is this normal during a parallel of two generators where lead generator is higher in both load ampere and reactive power than the lag generator but with the same frequency same kilowatt load?
No it is not normal. Ideally both the generators share the load equally provided both generator ratings and other parameters are same.
What is the difference between shunt generators and series generators?
1. In Shunt generators armature current is equal to sum of field current and load current whereas in series generators field current and load current is same. 2. Shunt generators field winding has high resistance and large no of turns as compared to series generators. 3. Shunt generator field winding has thin conductor and series generator has thick.
Why one of the generators has better regulation than the other?
You may be referring to properties know as speed droop and/or voltage droop. These are negative feed backs that retard the the speed and/or voltage of a generator as more load is added to the generator. This is necessary in order to balance load between generators so that one or more generators attempt to take more load than the others. If one generator took more load it would either become overloaded OR cause another generator to become unloaded to a point that it could be motorized and start consuming power path than producing it. In either case the is would be possible to have generators trip off line, possible in a cascaded trip. One one generator in the parallel group need be operated without droop so as to be the freq and voltage standard. The remaining generators added must have some amount of droop to prevent theme from hogging the load.
How long does it take for a hydro electric dam to generate 10000 gigawatts?
It depends on how much the grid is loaded that the dam's generators supply. The heavier the grid load the shorter the time frame to reach the load specified. Likewise the lighter the grid load the longer the time frame to reach the specified load.
How long does a man have to establish paternity?
It is totally dependent upon the case load of the presiding judge.
