Rigid Parallel Coupling Circuit
The rigid coupling principle allows a very compact coupling cell design and stable (load independent) signal voltages in the network. It consists of a band pass filter tuned to the ripple control frequency and an isolating transformer to separate low and medium voltage.
Experience has shown that most customers prefer the rigid type of coupling, and that, with time, they will change from other types of coupling (e.g. loose coupling) to the rigid coupling because of its advantages.
The high coupling efficiency of the rigid coupling, with consequent low losses, leads to an economical transmitter design. It guarantees a stable ripple control injection voltage that is within the specified range almost independently of the load. The coupling circuits offered by Swistec are designed for the necessary signal level taking into consideration the parameters of the MV network.
The main benefits of rigid parallel coupling circuit are:
- Stable ripple control injection voltage
- The output can be selected using different taps at the isolating transformer
- The ripple control signal is load independent
- Easy tuning of each phase by choosing the correct tapping on the coil
- Easy retuning in case of a capacitor change
- High quality factor
- Low losses
- Compact construction, especially when mounting components above one another
- The rigid parallel coupling is the most widely used type of ripple control coupling throughout the world