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A synchronous condenser is an overexcited synchronous motor, which draws leading currents from the system and hence compensates for lagging VARs. It is used as a reactive power compensator for power factor correction purposes. This synchronous motor running without load i.e. over excited is synchronous condenser.
How can a synchronous motor be used as a synchronous condenser explain also compare a synchronous condenser with the static condenser?
Unlike a static capacitor bank, the amount of reactive power from a synchronous condenser can be continuously adjusted. Reactive power from a static capacitor bank decreases when grid voltage decreases, while a synchronous condenser can increase reactive current as voltage decreases.
When the synchronous motor is called a synchronous condenser?
When the motor is operated at no load with over-excitation, it takes a current that leads the voltage by nearly 90 degrees. Thus, it behaves like a capacitor and under such operating conditions, the synchronous motor is called a synchronous capacitor.
What are synchronous condensers used for?
Technology Types. A synchronous condenser is a conventional solution that has been used for decades for regulating reactive power before there were any power electronics compensation systems. A conventional synchronous condenser is an AC synchronous motor that is not attached to any driven equipment.
What is a synchronous motor used for?
Synchronous motors are normally used in applications in which a constant and precise speed is required. Typical applications of these low power motors are positioning machines. They are also used in robot actuators. Synchronous motors are also used in ball mills, watches, record players, and turntables.
What are the disadvantages of synchronous condenser?
(i) There are considerable losses in the motor. (ii) The maintenance cost is high. (iii) It produces noise.
How does synchronous condenser operate explain with phasor diagram?
Synchronous Capacitor or Condenser V Curve As the active power provided to motor is 0, at unity P.F that means armature current is zero. As the IF is augmented over this point, the line current upsurges in a linear manner until get saturation. The given figure shows the result of increment in IF on phasor diagram.
How do you start a synchronous motor?
Starting a Synchronous Motor Using Slip Ring Induction Motor The resistance is gradually cut-off as the motor gains speed. When it achieves near synchronous speed, DC excitation is given to the rotor, and it is pulled into synchronism. Then it starts rotating as a synchronous motor.
What do you mean by synchronous speed?
: a definite speed for an alternating-current machine that is dependent on the frequency of the supply circuit because the rotating member passes one pair of poles for each alternation of the alternating current.
How much does a synchronous condenser cost?
Normally, the mean cost for a synchronous condenser is between $10 to $40 per kVAR and the maintenance cost ranges from about $0.4 to $0.8/kVAR per year.
How does a synchronous condensers work?
The synchronous condenser aids voltage regulation by drawing leading current when the line voltage sags, which increases generator excitation thereby restoring line voltage. A capacitor bank does not have this ability.
Which among these is the advantage of synchronous condenser?
Helps in achieving the stepless control of power factor. b. The motor windings have a lower thermal stability.
Where are synchronous condenser installed?
Installed at strategic intervals along a transmission system, synchronous condenser systems are either new electrical rotating equipment or existing turbogenerators reconfigured to perform as reliable grid stabilizers.
What are the main parts of synchronous motor?
The Construction of Synchronous Motors A synchronous motor is generally made up of two parts, a stator the stationary part of the machine that carries the armature winding in which the voltage is generated, and a rotor the rotating part of the machine that produces the main field flux.
How do you know if a motor is synchronous?
The speed of the rotating stator field is called the synchronous speed. The frequency of the power supply and the number of poles of the machine determine the synchronous speed. A synchronous motor is one in which the rotor turns at the same speed as the rotating magnetic field in the stator.
What are 3 types of motor controls?
There are mainly there are three types of motor control circuits: Direct On Line Starter (DOL starter) Star Delta Starter. Auto Transformer Starter.
Why synchronous motors are not self starting?
Above a certain size, synchronous motors are not self-starting motors. This property is due to the inertia of the rotor; it cannot instantly follow the rotation of the magnetic field of the stator. Once the rotor nears the synchronous speed, the field winding is excited, and the motor pulls into synchronization.
What are the advantages of synchronous compensator?
Advantages of synchronous condenser: The reactive power can be adjusted continuously. They are giving better performance than the static capacitor in the high voltage system. Maintenance-free. A high degree of safety can be maintained.
Why Statcom is used?
The Static Synchronous Compensator (STATCOM) is used in an HVDC system to provide reactive power compensation. It makes use of the Voltage Source Converter (VSC) to synthesize a controllable sinusoidal voltage at the fundamental frequency.
What do u mean by synchronous condenser?
In electrical engineering, a synchronous condenser (sometimes called a synchronous capacitor or synchronous compensator) is a DC-excited synchronous motor, whose shaft is not connected to anything but spins freely. Synchronous condensers are an alternative to capacitor banks for power-factor correction in power grids.
Which of the following is true for synchronous condenser?
It is a synchronous motor with capacitor connected across stator terminals to improve power factor. It is an over-excited synchronous motor partially supplying mechanical load, and also improving power factor of the system to which it is connected.
How an over excited synchronous machine improves power factor?
By varying the DC excitation of the motor, the power factor of the motor can be varied widely. Overexcited synchronous motors operate at leading power factor and provide reactive kVAR-like capacitors. This yields an improved power factor for the power-supply system.
Why the speed of synchronous motor is constant?
Synchronous motors are constant speed motors. They run at the synchronous speed of the supply. As you can see, the synchronous speed depends on the frequency of the supply and the number of poles of the rotor. Changing the number of poles is not easy, so we do not use that method.
What is the formula of synchronous speed?
The synchronous speed of an AC motor is determined by the frequency of the source and the number of poles. The RPM is calculated by multiplying the frequency times 60 and dividing by the number of pairs of poles. This was explained in Chapter 6. Some motors are designed to operate at synchronous speed.
Which type of starter is used for synchronous motor?
Controllers for synchronous motors have four components: a three-pole starter for the ac stator circuit, a contactor for the dc field circuit, an automatic synchronizing device to control the dc field contactor, and a cage-winding protective relay to open the ac circuit if the motor operates too long without.
