Search Product
  • PCS-993 Out-of-Step Controller

  • Power systems are required to remain stable after experiencing any disturbance, which may be caused by a fault, loss of a generator, or loss of a transmission line. Some disturbances may cause out-of-step between the interconnected systems, which may lead to blackouts and equipment damages if no remedial measures are taken to prevent this. In order to avoid these results, the PCS-993 out-of-step controller presents an effective way to prevent system collapse caused by out-of-step.

    When the out-of-step condition is detected, the PCS-993 controller will take corresponding actions to maintain a balance between load and generation. These measures include tripping associated circuit breakers to separate the power system into two or more smaller islands at the pre-selected points, shutting down some generators, shedding appropriate loads and triggering other related synchronizers preparing for the system synchronism after the system separation.

    The PCS-993 controller adopts the advanced multi-processor platform, supporting IEC 61850-8-1 MMS. In addition, it incorporates the RJ-45 faceplate port for testing and setting in order to make commissioning and maintenance easier.

  • Send Inquiry Now

Protection & Control
  • Out-of-step discrimination.
    Based on measurement impedance, R-X plane is divided into six sequential zones. The PCS-993 controller provides two tripping modes for different oscillation cycles; which are the fast tripping mode and the slow tripping mode. The fast tripping mode can operate in the first cycle of out-of- step for oscillation cycles of 200ms and above. The fast tripping mode operates in the second cycle of out-of-step for oscillation cycles of 100ms~200ms. The slow tripping mode operates with the same criteria as fast tripping mode but after 2~15 cycles out-of-step subject to the setting. Therefore, it only serves as a backup operation.
  • Protection zone restriction
    According to dedicated zone measurement elements, the operating zone is individually determined.
  • Out-of-step protection. (78)
    • Separation
    • Shutdown
    • Trigger synchronism

Monitoring and Measurement
  • VT circuit supervision (VTS)
  • CT circuit supervision (CTS)
  • Self diagnostic.
  • Event recorder including 1024 change-of-binary-input events, 1024 supervision events and 1024 operating logs
  • Disturbance recorder including 32disturbance records with waveforms (The format of disturbance recorder is compatible with COMTRADE.)

  • Up to 4 10Base-T/100Base-TX copper Ethernet ports using IEC 61850 protocol, DNP3.0 protocol or IEC 60870-5-103 protocol over TCP/IP
  • Up to 2 100Base-FX optical Ethernet ports using IEC 61850 protocol, DNP3.0 protocol or IEC 60870-5-103 protocol over TCP/IP ( Sharing with 2 copper Ethernet ports)
  • 2 RS-485 serial ports using IEC 60870-5-103 protocol
  • 1 RS-485 serial port for clock synchronization

User Interface
  • HMI interface with large-size LCD and 9-button keypad on the front panel
  • 1 front RJ-45 port for testing and setting
  • 1 RS-232 or RS-485 rear port for printer
  • Language selection – English + selected language
  • Assistant software - PCS-Explorer
  • Measured impedance characteristic with perspicuous physical conception employed for out-of-step condition detection.
  • Data measurement, protection calculation, logic discrimination, event recording and protection logic calculation are processed within one sampling period.
  • Out-of-step discrimination for parallel lines is integrated for diverse parallel-line applications.
  • Fast tripping mode and slow tripping mode are provided for different oscillation cycles.
  • The patented adaptive floating threshold is immune to system unbalance and disturbance.
  • Unique two-out-two logic is adopted in hardware design to improve security, coordinating with a redundant protection scheme, which improves dependability. The two independent data acquisition paths are provided to prevent mal-operation caused by component failure. One works as a fault detector and the other is designed for protection logic. Both data acquisition paths supervise tripping outputs.
  • The relay is designed based on NR Electric’s well- established and proven hardware platform with multi- processor architecture. The multi-CPU technology supports parallel operation.