Measuring & Control Unit NSD500V

NSD500V is a new bay level intelligent bay control unit for measurement and control of high voltage and extra-high voltage substations and network control system of large power plants. It meets the IEC standard for structure of automatic substation systems. The device supports both traditional and electronic transformer sampling. For electronic transformer sampling, the digital quantity of AC current/voltage is directly connected to the protective device via the merging unit (MU). The digital input interfaces are subject to the protocols defined in IEC61850-9-2 with the quantity meeting the demand to direct connection with several MUs. The device tripping/closing commands and other signals can be output in traditional cabling modes or in GOOSE.

  • Overview
  • Application
  • Features

NSD500V measuring and control unit is an intelligent device which can be applicable to monitor the electric parameters of the lines, busbars or main transformers in substations of 110kV and above. The device can realize the measuring and control functions in local bay, such as AC sampling, digital signal collecting, synchronism checking, switch control, and anti-misoperation block, etc.

NSD500V is a new bay level intelligent bay control unit for measurement and control of high voltage and extra-high voltage substations and network control system of large power plants. It meets the IEC standard for structure of automatic substation systems. The device supports both traditional and electronic transformer sampling. For electronic transformer sampling, the digital quantity of AC current/voltage is directly connected to the protective device via the merging unit (MU). The digital input interfaces are subject to the protocols defined in IEC61850-9-2 with the quantity meeting the demand to direct connection with several MUs. The device tripping/closing commands and other signals can be output in traditional cabling modes or in GOOSE.

The diagram of the protection system based on the combinations of different sampling situations is showed in Figures below.

  • Hardware design platform of high performance, modular design of CPU (central processing unit) and DSP (digital signal processor);
  • Whole panel, fully enclosed enclosure, separation of weak/strong current: The associated anti-disturbance measures are taken during software design, which will greatly improve the anti-jamming capability of the device;
  • High-speed 80-point sampling, real-time parallel calculation, re-sampling based on software frequency tracking, 64-point FFT fast software algorithm, and high measuring precision;
  • With perfect timing and time-keeping functions, the device supports IRIG-B timing and second pulse timing protocol, adopts high-precision temperature compensated crystal oscillators, and supports long-time high-precision time keeping;
  • Station control level adopts double 100M optical fiber Ethernet or electric interface Ethernet;
  • Full-station logic lockout function. Each output object has independent logic lockout contact output; the data of the whole station are shared; and the device can realize the logic lockout of full-station control operation;
  • Power grid harmonic monitoring function. The device monitors 2~13 times of harmonic content HRUk of voltage and 2~13 times of harmonic content HRIk of current;
  • The device has the function of synchronous breaker closing, and supports the differential frequency closing, same-frequency closing and no-voltage closing of breaker, as well as the amplitude compensation and phase angle compensation of voltage at both sides of synchronous point;
  • Perfect device self-check strategy;
  • Friendly human-machine interface.