■ Product Introduction
The application of high-voltage direct current transmission, flexible alternating current transmission system (FACTS), and large-scale integration of new energy have introduced a large number of power electronic devices into the power grid, injecting a large amount of inter harmonic and sub/super synchronous oscillation signals into the grid, which poses great risks to the safety and economic operation of new energy power plants. To strengthen the monitoring and analysis capabilities of the power system dispatch center for dynamic stability of the power system, broadband measurement devices are installed in important substations, converter stations, new energy stations, etc., gradually constructing a wide area broadband measurement system for the power system. To analyze the dynamic process of the power system for the dispatch center, provide sufficient data, and combine with the EMS system and safety automatic control system to strengthen the monitoring of the dynamic safety and stability of the power system.
The system achieves broadband oscillation monitoring, sub synchronous/ultra synchronous oscillation monitoring, waveform recording, and real-time data transmission through broadband measurement devices. The NseaDB Xihe database is used to store and analyze millisecond level harmonic components and microsecond level waveform recording data.
■ System functions
Broadband measurement device: responsible for synchronous acquisition, measurement, waveform recording, and real-time data transmission; It has real-time monitoring of harmonics/interharmonics, low-frequency oscillation monitoring, sub/ultra synchronous oscillation monitoring, broadband oscillation monitoring, time synchronization and monitoring functions. Mainly supports the following functions:
• High frequency synchronous sampling
• Power frequency phasor measurement
• Non power frequency electrical quantity measurement
• Subsynchronous/hyper synchronous and wideband oscillation measurement
Broadband processing unit: a device used for collecting, storing, and forwarding broadband measurement data at the station end. It has data preprocessing and analysis capabilities, supporting customized transmission of raw measurement data, preprocessed data, and diagnostic analysis results to the main station, while receiving operational commands issued by the main station. Mainly supports the following functions:
• Data storage and long wave recording
• Battlefield data analysis
• Collaboration between main and secondary stations
• Data preprocessing and analysis functions
