A synchronous generator is operating at lagging power factor (positive P & Q) when it is supplying P & Q to the system. P & Q are positive which means that they are flowing away from the bus where the generator is connected (overexcited case). On the other hand, it is operating at leading power factor when it is supplying P and absorbing Q. The sign of Q is negative which means that it is flowing towards the generator bus (underexcited case).
It depends on the maker. Many use nickel or brass. Some use rose brass (different color and a slightly darker sound). Brass is a slightly darker sound than nickel. Yamaha makes their valves out of an alloy (combination) of metals. This combination is more reactive to the saliva of certain people, and this may cause the valves on Yamahas to stick for some people. For this reason, it is important that you properly maintain the horn or simply do not buy a Yamaha if you find that you have this reactive saliva.
It is a term used in words, it doesn't really mean anything, so yeh that's it
As is the case with most historical divisions, including those involving music, successive periods are nearly always "reactive" to preceding periods in some significant ways while also being continuations in other ways. Musically, the Baroque Period reacted to the Renaissance by stressing complex harmony and refined ornamentation, along with natural themes and new forms. At the same time, it continued the Renaissance emphasis upon sacred themes and forms as the primary basis for composition.
Atoms that don't have a full octet are typically those that have fewer than eight electrons in their outer shell, which can make them more reactive. Examples include hydrogen, lithium, and beryllium, which can form bonds to achieve a stable electron configuration. Additionally, elements like boron may also have incomplete octets, often forming compounds where they share electrons with other atoms. These atoms tend to seek additional electrons through chemical bonding to reach a more stable state.
There is dust or corrosion in the potentiometer behind the knob. You need to turn the volume knob between 1 and 11 over 9000 times to wear the track clean again. If that does not help taking the electronics tray out of the amp (don't break the wires and don't electrocute yourself) to check if the volume potentiometer has any holes. Using a can of compressed air or non-reactive solvent from an electronics store with the thin nozzle tube supplied, blow or flush out the dust. If it really annoys you and you can't get rid of it, replacing the potentiometer(s) with new sealed ones will overcome the problem forever. or use standard ones and remember to turn the knobs every week to stop dust from settling. PS. if it is a high powered amp there will be capacitors inside that can seriously hurt you even when the amp is unplugged.
because the generator generate apparent power in kilos and it is written as ( kilo volt ampere OR KVA) it is the combination of active and reactive powers where active will be used by the consumers and the reactive will come back to the generator.
we do not use induction generator because it require an external source (synchronous generator) that provide reactive power to it.
reactive maintenance is a repair carried out when equipment fails.
Per factor is 1 when reactive power is zero.
In an electric generator, the function of a capacitor is to provide reactive power and improve the power factor of the generator. When a generator is connected to a load, the load may have a combination of resistive, inductive, and capacitive components. Inductive loads can cause the power factor of the generator to decrease, resulting in lower efficiency and voltage regulation. By adding a capacitor in parallel with the generator, the reactive power generated by the capacitor can offset the reactive power of the inductive load, leading to improved power factor correction. This helps to enhance the efficiency of power transfer and stabilizes the voltage. The capacitor absorbs and supplies reactive power, reducing the strain on the generator and ensuring a steady and efficient supply of electrical energy.
Generators can be required to generate real and reactive power. When operating in a leading mode, the generator is generating real and leading reactive power (inductive power). This means the generator is "sucking in VARS", which will pull down the terminal voltage similar to an inductor. It can also be operated in a lagging mode, which means it is generating real and lagging reactive power (capacitive power). The generator, then, is "pushing out VARS" like a capacitor, which will cause the terminal voltage to increase. Generators can only create so many leading and lagging VARs; in general lagging VARs are limited by the automatic voltage regulator output capabilities; leading vars are limitted by how much heat the stator can dissipate.
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.
They will run with different reactive power output, i.e. reactive load won't be equally shared between units.
Yes and no. One generator may be operating in the leading VAR region, and the other may be operating in the lagging VAR region. This would result in reactive current effectively circulating between the two generators.If you are talking about active (real) power, this should not happen, and will cause protective equipment to trip. Generators should generate real power, not consume it.
The reactive part dissipates no power because in a reactor the current is 90 degrees out of phase with the voltage. The effect of this is that any power that leaves the generator on one quarter-cycle comes back to the generator on the next. The net power is zero.
when excitation fails,Reactive power will be supplied by the system to which the generator is connected and generator will work as induction generator and its speed will rise a little. generator which was in over excitation mode will work in underexcitation.but there is under excitation limit which should not be reached so we should detect loss of excitation and trip 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.