secureC is a process KBR has developed to ensure the safe operation of reactive current compensation systems. It consists of different technical and organizational measures:
- Resonance frequency monitoring of each individual stage.
- Capacitance monitoring of each individual stage.
- Stage fuse monitoring.
- Stage contactor monitoring.
- Advanced temperature management of the stages and cabinets.
- KBR ventilation concept.
- Durable multicond UHPC capacitors.
- Highly linear multiind inductors.
For secureC systems, the user will receive an extended warranty on the system. With only a few exceptions (target cos / current transformer, etc.), only specially trained service personnel may access the individual controller setting parameters.
Monitoring resonance frequency, stage back-up fuse and relay contacts
resonance frequency is continually changing. This means that even a correctly set up unit can become a potential danger the longer it is in operation. The inevitable shift of the resonance points through loss of capacitance is accounted for by secureC as it calculates the resulting new resonance frequency. Evaluating the resonance frequency is performed taking into account the programmed inductor factor. If critical frequencies are reached, the display issues corresponding warnings that are logged in the event memory. If previously defined resonance frequencies are exceeded, the stages involved are switched off or blocked if necessary. The secureC concept also detects when individual fuses blow or contactor contacts ‘stick’.
Temperature management
The secureC concept also features a special temperature management system. Conventional controllers simply switch off the entire system if a limit temperature is reached, and put up with not only reactive current costs but also very high apparent current, which can also trigger switches. The temperature management system of secureC on the other hand, ensures that such cases are avoided as far as possible. As before, the fans are activated when the first temperature threshold is reached – separately for each cabinet, of course. If this is not sufficient, and an equivalent stage is available in another cabinet (stage power, detuning, thyristor/contactor), this is used as an alternative. Even if the emergency switch-off temperature is reached despite these preventive switching operations, not all stages are taken out simultaneously, but one after another, with a delay of two minutes.