0
Generator Capability Curve study
Wiki User
∙ 15y ago
Add your answer:
Earn +20 pts
How do you define the synchronous generator capability limiters?
SYNCHRONOUS GENERATOR CAPABILITY LIMITTsynchronous generator capability limiters are as follows 1.MVA or armature current limit of generator: this depends on the cooling system of generator so that temperature rise in generator is limited to safe value.depending on cooling system effectiveness and temperature limit for the insulation used in generator, MVA limit is decided.2.MW limit: this is determined by the power output capacity of prime mover to which generator is connected.3.rotor angle limit: this is related to stability of generator which is synchronised to the grid.ideally this could be 90 degree, but in practice this is limited to70 degree so as to have better stability margin in transient and dynamic condition.the generator falls out of synchronism in trasient condition if rotor angle is close to 90 degree.4. rotor current limit: the field winding placed on rotor has got limited current carrying capacity, beyond which it may burn .so this limit is used.all these limitters make capability curve of g generator within which the generators operates safelyr. k.niranjanemail id: rkniranjan@yahoo.com
Why electric generator drop the load?
Too much load for the generator, the generator began to under speed / overspeed, the governor / part of the generator went into failure, the generator capability was not up to the requirements placed by the system (needing to push out/pull in too many VARs), etc. there are many reasons for a generator to drop a load. Because a load dropped, this does not infer that the generator was the cause either (fault on the system, system instability limits reached, system protection tripped - non-generator related protection).
What information is found on transformer nameplate?
The plate should as a minimum show the working voltage, volt-amp capability and the rpm of the generator. Other optional information is the manufacturer and serial number.
Magnetising characteristics of DC shunt generator?
the magnetizing curve is the relation b/w air gap flux and the field winding current armature EMF. the resulting curve is called magnetizing characteristics or open circuit characteristics. at any speed by recognizing that the induced emf is directly proportional to the speed
Does load affects fuel consumption per hour of a diesel generator?
If the generator is to maintain the same rpm and power output, then a heavier load will increase the diesel consumption. The revolutions per minute the generator runs will increase as the load increases, thereby resulting in an increase in diesel consumption to maintain the high rpm. A Generator has a governor which attempts to maintain frequency at 60 Hz for North America. For the generator to increase the power output at the same frequency, the governor will increase the fuel and air to the engine. The fuel consumption will not be linear because of the curves associated with the particular engine. The fuel to KWH is know as the heat rate curve for the generator.
What is a Generator capability curve?
The generator capability curve described the capability real and reactive power capability of a generator. Real power is plotted on the horizontal axis, while reactive power is plotted on the vertical axis. A reactive capability curve consists of three curved segments. One segment is the arc of a circle centered at the origin of the reactive capability curve. Because the radius of that circle is the apparent power, S (in MVA), it is based on the thermal heating limitations inherent in the stator winding and reflects the fact that the stator limitation is based on current alone. The second segment is an arc of a circle centered on the Q axis - the arc joins the positive Q axis with the constant MVA portion of the curve, and defines the upper boundary of reactive power OUT of the generator. It is the arc of a circle because it also reflects current-based heating; the critical difference is that the limitation described is that of the rotor winding. The third segment joins the negative Q axis (representing reactive power into the machine) with the constant MVA portion of the curve. This segment reflects end-ring heating while in underexcited operation. When you change the tap on the generator step up transformer, you will change the reactive output of the generator. Remember that reactive (VARS) always flow downhill in voltage - from higher voltage to lower voltage. So if you change the tap on the transformer to produce a lower open-circuit secondary voltage, the reactive output of the generator will increase. Conversely, if you change the tap to cause a higher open-circuit secondary voltage, the reactive output of the generator will decrease.
Why alternator power factor 0.8?
In terms of generators, the alternate power factor is generally 0.8 for most models. This factor is defined as the power needed to operate within the limits of he generator capability curve.
How do you define the synchronous generator capability limiters?
SYNCHRONOUS GENERATOR CAPABILITY LIMITTsynchronous generator capability limiters are as follows 1.MVA or armature current limit of generator: this depends on the cooling system of generator so that temperature rise in generator is limited to safe value.depending on cooling system effectiveness and temperature limit for the insulation used in generator, MVA limit is decided.2.MW limit: this is determined by the power output capacity of prime mover to which generator is connected.3.rotor angle limit: this is related to stability of generator which is synchronised to the grid.ideally this could be 90 degree, but in practice this is limited to70 degree so as to have better stability margin in transient and dynamic condition.the generator falls out of synchronism in trasient condition if rotor angle is close to 90 degree.4. rotor current limit: the field winding placed on rotor has got limited current carrying capacity, beyond which it may burn .so this limit is used.all these limitters make capability curve of g generator within which the generators operates safelyr. k.niranjanemail id: rkniranjan@yahoo.com
Importance of load characteristics of a generator?
I assume this is asking about the capability curve of a generator. A generator can only produce so much actual power (kW) at a specific power factor. As power factor changes, the amount of current flowing that is due to reactive power will also change. The total current Ix (reactive power) + Ir (real power) will cause heating in the generator, and so the generator can only kick out so much current, be it real power or reactive power. Reactive power is used to control the voltage (drag it down, or push it up) and change phase angles to push more power down specific lines. If the load on a generator is such that it's expected to generate power outside its' capability curve, terminal voltage may begin to sag (which will cause the generator output power to be less, potentially exacerbating the problem), or may float too high (potentially damaging equipment). Excessive heating in the generator can also result, and protective devices may kick in to trip the generator off line.
How to draw capability diagram of synchronous generator using matlab?
The Capability Diagram Normally, the generator meets all the voltage and frequency requirements of the grid. This can be achieved with two closed -loop controllers # Change of excitation current of the rotor or as so called the AVR # change of fuel supply to the turbine or as so called the GOVERNER But in order to prevent damages caused by high temperature or asynchronous operation, several limitations and design criteria are installed to determine the operating zone of the generator These limitations are: # excitation current (rotor current ) limitation # Stator current limitation # load angle( not the power factor) limitation According to these limitations, the designers of the generator draw the capability curve at certain cold air temperature A circle with the radius of the maximum excitation current limitation, another circle with maximum stator current. The point where these two circles intersect is called the "Design point" of the generator.
What is the background of the study of generator from a toy motor?
It has electric!
Why electric generator drop the load?
Too much load for the generator, the generator began to under speed / overspeed, the governor / part of the generator went into failure, the generator capability was not up to the requirements placed by the system (needing to push out/pull in too many VARs), etc. there are many reasons for a generator to drop a load. Because a load dropped, this does not infer that the generator was the cause either (fault on the system, system instability limits reached, system protection tripped - non-generator related protection).
What is mechanisms of van de graaff generator?
The purpose of the Van de Graff generator was for it to be used to study static charge
How many years does a chartered accountant study to complete his degree?
its usually 4 years but depends on your capability to complete
How do you become the smartest girl in class?
First you need to be born with the intellectual capability and then you need to study really hard.
What is compounding curve in synchronous motor?
The operation of a synchronous generator delivering power to a constant power-factor load is demonstrated by means of compounding curves. A compounding curve shows the field excitation needed to maintain rated terminal voltage as the load is varied.
Advantages and disadvatages of a self excited induction generator?
The main disadvantage should be obvious - when the output voltage of the generator is used to provide field current to the generator....what happens if the output voltage sags? If the output voltage becomes depressed, the output power of the generator is compromised (becomes less and less), this in turn can cause the output to become more depressed, leading to an incrementally decreasing output capability. The main advantage is cost savings.
