Smart substations feature digitalization of full-station information, networking of communication platforms and standardization of information sharing as their basic characteristics. They automatically complete basic functions such as information collection, measurement, control, protection, metering and monitoring, and support advanced functions such as real-time automatic control, intelligent regulation, on-line analysis and decision-making, and collaborative interaction of the power grid as required, realizing interaction with adjacent substations and power grid dispatching.

As an important station control layer device, the data communication gateway (remote terminal unit) of smart substations communicates with the bay layer devices in the station downwards and conducts real-time interaction of remote control information with dispatching centers at all levels upwards. It is a key device supporting the integrated dispatching and control operation of smart substations and is crucial to the safe and stable operation of the power grid. The joint commissioning of dispatching information between the master station and the substation has become a key task in the engineering commissioning stage of the smart substation monitoring system.

△ Integrated Acceptance Device for Substation Monitoring Information

The Integrated Acceptance Device for Substation Monitoring Information simulates the dispatching master station, communicates with the on-site remote terminal unit of the substation in real time, conducts synchronous acceptance inside the station, and sends acceptance signals to the dispatching master station in batches, improving the accuracy and speed of point checking.

△ System Schematic Diagram

System Principle

Before the optical fiber link between the dispatching center and the substation is established, the device simulates the dispatching master station for synchronous acceptance, solving the signal problems existing in the entire link of in-station signals originating from intelligent terminals, merging units, etc., passing through protection and measurement & control devices to the monitoring background and data communication gateway.

Configuration Verification

Verify whether the data communication gateway is configured in accordance with the point list and SCD file, and check for misconfiguration, missing configuration, redundant configuration and other irregularities. Two methods are adopted according to the presence or absence of an RCD file: one is to use panoramic information scanning to automatically match the IEC61850 data paths of the point list and SCD file; the other is to send data in sequence according to the point list based on the RCD file.

After the dispatching optical fiber link is established, the multi-IED MMS simulation module is connected to the data communication gateway. The module sends MMS messages with telemetry and remote signals as the input excitation end to replace the actual telemetry and remote signals of substation-side devices and transmits them to the master station, completing the acceptance of dispatching master station signals.

△ Application Site of a 500kV Smart Substation

Field Application

Before the commissioning of a 500kV smart substation, 3837 remote signal points, 493 telemetry points and 135 remote control points were collected in the dispatching information list. The DL-1801AC device is independent of switches, simulates cross-network segment communication of four dispatching master stations at the same time, and conducts synchronous acceptance in full accordance with the IP address of the master station dispatching center, with the whole process featuring simple wiring and easy operation.

Data Setting

Import the SCD file and the point list issued by the dispatching center, and set the IP address.

Synchronous Acceptance in Station

Simulate the dispatching master station through data setting, trigger signals on site, accept remote signal points according to the received action and reset signals, and accept telemetry points by applying actual analog quantities.

Master Station Acceptance

Through the imported SCD file, simulate the communication between all IED devices and the data communication gateway, automatically send all accepted remote signal points to the dispatching master station according to action and reset status, and send telemetry values of point number + 0.99 to the dispatching master station for acceptance.

By using the Integrated Acceptance Device for Substation Monitoring Information, the in-station synchronous acceptance work was completed in one week, and the acceptance work with the dispatching master station was finished in only 2 hours. The device features high efficiency and stable operation during use, greatly accelerating the project progress, winning time for the smooth commissioning of the substation, and receiving unanimous praise from on-site users.