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S-PRO Sub-Harmonic Protection Relay

S-PRO Sub-Harmonic Protection Relay

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The S-PRO sub-harmonic protection relay protects various power system equipment including generators, wind turbines, PV system, series compensated transmission lines, FACTS devices and power transformers from uncontrollable sub-synchronous oscillation conditions known as:

  • sub-synchronous torsional interaction (SSTI)
  • sub-synchronous control interaction (SSCI)
  • sub-harmonic resonance (SSR)
  • sub-harmonic ferroresonance

 These sub-synchronous oscillation conditions introduce opportunities for an exchange of energy at a given sub-synchronous frequency of the system. This exchange of energy results in stress on the power system elements involved that can lead to severe damage.

The S-PRO relay detects these undamped sub-synchronous oscillations and allows the utility to monitor and protect the power system by isolating the healthy grid from sub-harmonic generation sources.

Features and Benefits

  • Provides real time processing of voltage and current signals at all sub-harmonic frequencies in the range of 5 - 55 Hz (60 Hz system) and 5-45 Hz (50 Hz system) with a detection resolution of 0.2 Hz
  • Operating speed between 200-450ms
  • Provides incident trending to protect generators and other equipment against sustained sub-harmonics beyond normal levels that may not exceed levels that will cause SSR
  • Operations per duration settable for durations from 1-60 minutes
  • Events accumulated over a long period of time can be used to flag maintenance requirements
  • Sub-harmonic measurements monitoring through 61850 GOOSE, DNP 3 and Modbus.
  • Total Sub Harmonic Distortion (TSHD) reporting
  • 59, 27 and 50LS protection at <1.5 cycles
  • 2nd and 5th Harmonic Blocking for reliable operation under inrush conditions
Flexible Communications
  • State-of-the-art communications (2 rear ports, 100BASE-TX RJ-45 or 100BASE-FX 1300 nm multimode optical with ST style connector to accommodate the industry’s latest network-based communications)
  • Ethernet ports with 2 unique MAC addresses that easily accommodate network access security needs
  • Front panel USB and 100BASE-TX RJ-45 Ethernet port interfaces (readily accommodate modern standard laptops)
    Reduced Cost
    • Substation automation cost - includes IEC61850 protocol to display and transfer operational data via local-area network (LAN) for local HMI and wide-area network (WAN) for remote monitoring SCADA
    • Substation engineering, installation and commissioning cost and times - IEC 61850 GOOSE messages communicate high-speed information between IED’s on the substation LAN (including transfer trips, interlocking, load-shedding, and commands)
    • Product setting time - 240 x 128 LCD graphical user interface provides convenient means to check/change specific settings and parameters
      Improved Overall Response Time
      • Expedited response to systems events (11 generic front panel LEDs can be mapped to internal elements) allowing operators to quickly identify the cause of system events
        Easy to Use
        • Flexible programmable logic for building customized schemes with ProLogic™ statements User-friendly,
        • Windows®-based relay setting and record analysis software
        • Enhanced DNP3.0 Level 2 SCADA communication protocol including user-selectable point lists, class support and multiple master station support
        • Exceptional fault recording capabilities with 96 s/cycle, all channels with events

          Download Items:

          S-PRO 4000 Data Sheet

          S-PRO 4000 Manual