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Large installations of synchronous condensers are sometimes used in association with high-voltage direct current converter stations to supply reactive power to the alternating current grid. Synchronous condensers are an alternative to capacitor banks for power-factor correction in power grids.
What is advantage of synchronous condenser?
The advantages of a synchronous condenser are that we can control the power factor of system smoothly without stepping as per requirement. In case of a static capacitor bank, this fine adjustments of power factor cannot be possible rather a capacitor bank improves the power factor stepwise.
Which device is suitable for a synchronous condenser?
A synchronous condenser is operated in a borderline condition between a motor and a generator with no mechanical load to fulfill this function. It can compensate either a leading or lagging power factor, by absorbing or supplying reactive power to the line. This enhances the power line voltage regulation.
What is synchronous condenser Quora?
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 in some systems for power factor correction purposes.
What are the advantages and disadvantages of synchronous motor?
Synchronous motors requires dc excitation which must be supplied from external sources. Synchronous motors are inherently not self starting motors and needs some arrangement for its starting and synchronizing. The cost per kW output is generally higher than that of induction motors.
Why the synchronous motor is 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 two factors determine 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 is a main advantage of the synchronous condenser compared to Statcoms?
It’s one that can be overcome by an unexpected technology—the synchronous condenser. Adding synchronous condensers can help with reactive power needs, increase short-circuit strength and thus system inertia, and assure better dynamic voltage recovery after severe system faults.
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 is synchronous speed and its formula?
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. Actual speed of the induction motor will be less than the synchronous speed.
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.
Which of the following is true for a synchronous condenser?
Right Answer is: D Synchronous condenser is an over-excited synchronous motor operating at no-load with leading power factor. The efficiency of long power transmission lines may be increased by placing synchronous condensers along the line to compensate lagging currents caused by line inductance.
Which is the case of under excitation?
Hence in this case the motor is said to operate under lagging power factor and the is said to be under excited. CASE 3: If the field current is more than the normal field current, motor is said to be over excited.
What are the advantages of installing a synchronous condenser in electrical system illustrate your answer with an example?
(i) By varying the field excitation, the magnitude of current drawn by the motor can be changed by any amount. This helps in achieving step less control of power factor. (ii) The motor windings have high thermal stability to short circuit currents. (iii) The faults can be removed easily.
When synchronous condensers are used to provide VARS leading vars are provided by?
VAR Compensator: For this purpose, a synchronous condenser can be used, as it can provide the required VARS by adjusting its excitation.
What are the applications of synchronous motor?
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 is 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.
Why does the synchronous motor run at synchronous speed?
The synchronous speed is the speed of the revolution of the magnetic field in the stator winding of the motor. Thus, an AC machine in which the rotor moved at a speed and built a constant relationship between the frequency of the voltage in the armature winding and the number of poles is called a Synchronous Machine.
What is the difference between synchronous motor and synchronous condenser?
The only difference between a synchronous motor and a synchronous condenser is the synchronous condenser shaft is not connected to anything—it simply spins unimpeded. The sole purpose of a synchronous condenser is to adjust conditions (power factor) on the electric power transmission grid.
Why synchronous motor is called a condenser?
Why synchronous motors are known as synchronous capacitors? 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.
Which generator can run at synchronous speed?
An induction generator produces electrical power when its rotor is turned faster than the synchronous speed. For a typical four-pole motor (two pairs of poles on stator) operating on a 60 Hz electrical grid, the synchronous speed is 1800 rotations per minute (rpm).
