Industrial Switch Solution of Smart Substation

The tide of smart substation construction has come, and more smart substations will stand on the vast land in the future.Experts believe that the construction of smart grid will become a strategic opportunity for China's economy to promote the transformation of the domestic demand system, and will drive the innovation and development of nearly 100 upstream and downstream industries.

Smart substation is a modern substation that is constructed by layers of intelligent primary equipment and networked secondary equipment on the basis of IEC61850 communication protocol, which can realize information sharing and interoperability among intelligent equipment.The most fundamental difference between smart substations and traditional substations is information networking.Among them, the Industrial Switch, which is the core equipment of the communication system of the intelligent substation, is responsible for the transmission of various control signals and management information.Under the background that merging units are generally used in smart substations to digitize sampling values at the process level, and data transmission relies on GOOSE messages to transmit primary device status and control commands, industrial switches, in addition to carrying traditional station-level communication services, began to gradually replace traditional cables. Maintain the central equipment associated with primary and secondary equipment.This change in role and importance has put forward very high requirements on the function, performance and reliability of industrial switches.How to measure and assess the relevant indicators of industrial switches is a problem that power users are more concerned about.

The so-called industrial switch, that is, an industrial Ethernet switch, means that it is technically compatible with commercial Ethernet switches (IEEE 802.3 standard), but it should be able to meet the needs of industrial sites in terms of material selection, product strength and applicability. That is to meet the needs of industrial sites in terms of environmental adaptability, reliability, safety and installation and use.Therefore, for the requirements of power industry switches, the focus is on the related functions of smart substations and the safety and reliability that meet the environmental requirements of substations.

The characteristics of digital substation network data are strong suddenness, large amount of data, and low requirements for real-time transmission.The characteristics of GOOSE network data are that the amount of data is small and bursty, and the transmission requires high reliability and real-time performance.By using virtual local area network to divide the VLAN network on the industrial switch side, the forwarding range of broadcast packets can be reduced, and network storms can also be suppressed.Industrial switches need to support priority and virtual LAN.This requires that industrial switches must be equipped with network management software, so that users can easily set parameters.

Basic requirements for industrial switches in smart substations

According to the definition of State Grid's "Technical Guidelines for Smart Substations", smart substations have basic requirements such as digitalization of all station information and networking of communication platforms, and these requirements put forward the following basic requirements for industrial Ethernet switches that carry communication networks: 1. High-performance information transmission to ensure the priority transmission of high-priority user data; 2, network flow control; 3, redundant network; 4, network condition monitoring and fault diagnosis; 5, high-precision network time synchronization protocol.

In response to the above requirements, Houshi Network has customized and developed industrial communication products such as the ISC1000 series, and its industrial switches already have relevant functions corresponding to them:

◆Completely follow the IEC61850 standard stipulation, fully compatible with all kinds of intelligent equipment in substations;

◆Adopt PRP parallel redundancy technology to realize dual access network, enhance network reliability, and network self-healing time is less than 20ms;

◆Provide access means for various serial signals of measurement and control devices, and convert them into standard Ethernet signals to realize transparent transmission of serial data;

◆Provide two optional synchronous clock schemes, either the IRIG-B code clock can be provided by the serial port, or the IEC61588 synchronous Ethernet clock can be provided by the Ethernet interface, and the time synchronization accuracy of a single unit can reach within ±10ns;

◆Through various mechanisms such as large-capacity cache, eight-level priority division QoS guarantee, VLAN isolation, controllable multicast, link redundancy and other mechanisms, zero packet loss is achieved for important multicast packets at the process layer such as GOOSE and SMV;

◆Industrial switch power supply is generally designed for redundant dual power supply, DC power supply mode, which effectively improves the safety and reliability of the system.

◆Inspection of dielectric strength and impulse voltage, the test standard is IEC 60255-5 or IEEE 1613, good insulation performance

◆Compact body, fanless shell heat dissipation design, working temperature range -40-+85℃, to meet the requirements of harsh and complex environments

◆Through comprehensive electromagnetic compatibility test, strong anti-interference ability

In general,our Industrial switches support power protocol requirements and level requirements, meet IES61850-3, IEEE1613 and other specifications, support various industrial power supply access, support high and low temperature, EMC protection level and enclosure protection level, etc. And the corresponding product tests meet the requirements of Various industry certification.