Synchronous condensers are rotating machines that help provide voltage support and reactive power compensation in AC (alternating current) power systems. They are used to improve the stability and efficiency of the electrical grid. Here's how synchronous condensers achieve these functions:
Voltage Support:
Voltage support is essential for maintaining the voltage levels within acceptable limits to ensure the proper functioning of electrical equipment connected to the grid. Synchronous condensers can help with voltage support in the following ways:
a. Reactive Power Injection: Synchronous condensers are designed to generate or absorb reactive power without producing active power (real power). When the grid experiences a voltage drop or a sudden increase in demand, synchronous condensers can inject reactive power into the system to help raise the voltage levels and stabilize the grid.
b. Voltage Regulation: Synchronous condensers can adjust their field excitation to control their reactive power output. By doing so, they can regulate the voltage at their connection point and help maintain the grid voltage within acceptable limits.
Reactive Power Compensation:
Reactive power compensation involves balancing the reactive power consumption and generation in the grid. Reactive power is needed by inductive loads like motors and transformers but does not contribute to useful work. Synchronous condensers can provide reactive power compensation as follows:
a. Capacitive and Inductive Mode: Synchronous condensers can operate in both overexcited (capacitive mode) and underexcited (inductive mode) states. In overexcited mode, they act as a source of capacitive reactive power to compensate for inductive loads, while in underexcited mode, they provide inductive reactive power to compensate for capacitive loads.
b. Power Factor Correction: By adjusting the excitation level, synchronous condensers can achieve power factor correction, which means bringing the power factor closer to unity (1). A power factor close to unity reduces reactive losses in the system and optimizes the use of electrical energy.
c. Dynamic Response: Synchronous condensers offer rapid response to changes in reactive power demand due to their rotating nature. They can quickly absorb or inject reactive power, making them valuable assets in supporting grid stability during sudden changes or disturbances.
Overall, synchronous condensers play a crucial role in maintaining grid stability, voltage regulation, and reactive power compensation in AC power systems, making them an important tool for grid operators to ensure reliable and efficient power distribution.