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  • Based on advanced technologies and vast engineering experiences, NR Electric provides innovative and field-proven solutions for AC transmission system to achieve reliable and flexible performance throughout the system. NR Electric analyzes the situation of each project and tailors the solutions to build the most suitable and valuable system to optimize our client’s investment. Currently, our solutions have been widely applied to over 10,000 substations ranging from 110kV to 1000kV with all over the world.

  • Protection & Control Automation Energy Management System De-Icing FACTS

    NR is dedicated to providing diverse protection and control products with well-proven technologies that have been widely applied to thousands of projects worldwide. The protection and control solution covers all primary assets including: generator, transformer, transmission line, busbar, circuit breaker, reactor, capacitor, feeder, motor etc.

    As for hardware architecture, NR's innovative two-out-of-two logic is implemented to eliminate mal-operations due to the component failure. The combination of the two-out-of-two logic and the implementation of a redundant scheme ensure the dependability and security of our protection and control solution systems. NR invented the Deviation of Power Frequency Component (DPFC), a protection principle, which can help identify and confirm the fault in milliseconds and aid in the issuing of control commands accordingly. NR's continuous focus on research and development has led to the creation of many innovative technologies and patents that have greatly improved the performance of NR’s protection products. 


    • Full-range protection and control solutions covering transmission line, transformer, busbar, circuit breaker, generator, reactor, feeder, motor and capacitor.

    • Successfully applied to the world highest voltage level - 1000kV UHVAC substations.

    • High speed fault clearance capability and well immunity to power swing and load fluctuation

    • System security and dependability enhanced by two-out-two logic in hardware design

    • Unique power swing blocking releasing logic to prevent mal-operation of distance protection for internal faults during power swing

    • Improved system security during CT saturation and sensitive to internal faults.

    • Fast and reliable busbar protection during CT saturation due to patented adaptive-weight anti-saturation algorithm and harmonic restrain algorithm

    • Both Δ→Y and Y→Δ phase angle compensation to realize phase segregated inrush blocking.

    • Customized system scheme such as flexible hardware design, scalable function library, programmable logics, configurable I/Os and definable LEDs

    • Fully compatible with IEC 61850 application Powerful disturbance recording function supporting post-fault analysis 

    NR’s superior automation systems enable realtime monitoring and control of system operating data, including asset management, power system status monitoring, remote/local control, fault analysis and evaluation, operators’ authorization, history data statistic analysis and communication for dispatching centers.

    The integrated automation solution is suitable for newly built substations and/or retrofit substations. The solution complies with IEC 61850 standards over double-star LAN or ring LAN. The network is composed of Bay Control Unit, Protective Relay, Fault Recorder, PMU, Protocol Converter, Gateway, GPS Receiver, Gigabit Switch and HMI Software. NR can also integrate metering and CCTV devices into the automation system. 


    NR’s automation solution is designed based on Ethernet communication and the whole system is hierarchical and distributed. The system adopts functional diversification and object-oriented design to improve availability for different applications.

    • Flexible and open system architecture

    • Advanced real-time database and historical database

    • Fully support the IEC61850 standard(Ed1 and Ed2)

    • Advanced IGML modeling

    • Friendly human machine interface

    • System offline maintenance and online update

    The Energy Management System (EMS) is an advanced control center solution to monitor, control, manage and optimize the generation and transmission network. It helps utilities or industrial customers to improve economic efficiency and lower operation cost. 

    With more than three decades of experience in supplying EMS to the electric utility, NR’s EMS Solution is the right control center solution to manage your complex power system, while ensuring the required level of cyber security. It is also an energy information system that provides reliable process information to all levels of decision makers in the organization. With the best service and hundreds of licenses deployed in China and all over the world from Substation, Wind farm to the largest National Dispatching centers, NR’s EMS solution is a versatile system to facilitate an efficient, secure and reliable grid operation, not only for managing today’s power network but also for tomorrow’s Smart Grid.


    • Distributed architecture with open-standard system to ease users’ operations

    • Unified supporting platform with increased reliability and simplified system integration

    • Extendable communication front-end to save your future investment

    • Realtime monitoring and control function with advanced visualization capabilities and user configurable dashboard

    • Precise regional Automatic Generation Control(AGC) function

    • Network analysis software with indispensable operation direction and practical algorithm

    • Dispatcher training simulator offering easy learning with a mirroring training system

    • Paperless dispatching management function 

    Severe weather conditions, such as frozen rain, can create ice coating on transmission lines and steel towers. More severe icing of conductors on steel transmission lines can cause the towers to buckle and the structure to fail, leading to interruption of power supply and threatening the safe operation of the whole power system. NR provides the innovative and versatile DC De-Icing solution to help customers solve the dangerous icing problems.

    The De-Icing solution adopts thyristor rectifier to convert AC current into DC current, and the DC current flows through the line resistance producing heat for de-icing. In severe climate situations, the De-Icer serves to melt the ice cover and reduce the risk of tower collapse. In other situations, the De-Icer could be used as SVC to compensate the reactive power in the power grid. NR can provide both fixed and relocatable De-Icing solutions depending on requirement from customer.


    • The use of thyristor rectifiers can reduce the impact on power system during ice melting and ease the switch-over operations.

    • The DC de-icer device supports large current and large angle continuous stable operation. It is applicable to tranmission lines with different conductor diameters and lengths.

    • The PCS-9590/9591 DC de-icer can adopt container type installation and valve hall installation, effectively saving the land resource, shortening the site construction period and easing the equipement transportation.

    • The device adopts reliable and compact structure with watercooling system and compact valve banks.

    • The PCS-9590/9591 is equipped with 6 phase seg circuit breakers enabling the automatic switchover among various ice melting modes and realizing the balanced ice melting for AC lines.

    • NR Electric also provides the high performance control and protection system for DC de-icing melting characteristics has been developed and features and high reliability.

    • Primary system of DC ice melting device requires only very small number of operations to realize SVC function. 

    Flexible AC Transmission System (FACTS) is a power electronics-based system that can enhance controllability, capacity and flexibility of the AC power network. NR’s FACTS solutions are built upon in-depth acknowledge of existing transmission systems, providing utility companies with fast voltage regulation, effective active power control and load flow control to improve the reliability and quality of power supply.

    Case Study ---- NR Protects China's First 1000kV UHVAC Link
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