110 kV substations digital transformation case analysisAbstract This paper briefly introduces the basic concept of digital substation, Analysised substation digitization reconstruction examples based on 110 kV substationsA. detailed analysised of the substation secondary equipmentsuch as changes in operating mode.Digital Substation discussed possible options for reform, and according to the results of the operation of digital substation work out countermeasures and Recommended.Key words digital substation 。 automation。 Electronic TransformerWith automation and computer network traffic monitoring and protection technology, the rapid development in Past two decadeshas made substantial progress has been achieved for the digital substation automation system . Network laid the technical foundation for fulfilling the other hand, with the special high-voltage large-capacity .The gradual formation of large scale grid, the grid stable and reliable control of the safety information exchange ， And put forward higher requirements of the urgent. Digital Substation substation construction will be Trends .1. the characteristics of digital substationThe basic features of digital substation can be summarized as: intelligent primary equipment, secondary equipment network, automated operation and management system. Since the station relative to conventional integrated, digital substation equipment, the protective principle, the internal algorithm, logic has not fundamentally changed, but in sampling digital, networked communication medium, communication interface standardization brought changes to improve the reliability of substation automation system. Reliability of information transmission can be achieved。 secondary wiring is simple。 measurement accuracy。 share unified information platform, reduce duplication of equipment 。 easy functionality expansion。 management automation.2. 110 kV Substation rehabilitation programs1 a part of. 110kV single busbar sub-main wiring methods, 110kV line 3 times, with a standby power source。 the main volume into 2 sets of 3 variables 。 35kV main connection method for the Single Bus, 35kV line 5 back。 10kV main connection is a single busbar way, 2 sets of capacitors, 10kV line 18 back, 2 sets of ground change, the replacement of transformers for the electronic, installation of PT parallel combiner。 replacement in situ terminal box, installation switches intelligent unit, to achieve local control switch 。 configuration integrated digital protection monitoring devices and digital power meter, equipped with digital standby power source device, care monitoring devices and focus group screen interval of combiner.2 station control layer. Station control layer consists of a units monitoring host, 2 Machines GPS communications management component to form the station control level star network, monitoring the host machine automatically selects the host communication management, communication management unit and the interval as an independent link layer device, and the bay level devices communication, access to remote, telemetry data, only the host with the remote authority, communication management unit interval of five anti-blocking cross-sequence and function of small1 / 8current grounding line, for the interval layer and process layer device when the hard right.3 spacer. Interval layer is the core of the station automation, communications related to the implementation of the process level GOOSE 35kV, 10kV lines, capacitors, ground change, sub-protective and monitoring local installation 。 110kV Main Transformer Protection and Control focus group back screen, installed in the control Room, located optical interface screen, providing the distance to the control room of the optical conversion interface。 three sides of the main transformer backup protection one, 110kV segmentation and one prepared from the cast。 monitoring interface communication, lockout protection association。 private GOOSE network to achieve important, the key trip control, station control layer GOOSE network, to achieve control of auxiliary tripping minor, such as the low cycle load shedding.4 the process level. Parallel combination provides voltage voltage, the output interval of combiner to provide the voltage signal。 the main transformer and back of each side of the differential transformer is divided into, setting separate combiner, combiner transformer transformer protection group in the main screen。 110kV line segment combiner configured individually, group within the control room screen line combiner。 35kV 10kV PT 1 set of each combiner configured to achieve PT parallel functions。 arranged in the sub-cabinet。 35kV 10kV part of the access by small-signal combiner, arranged in switch cabinet.5 communication network. a. station control station control interlayer layer network layer network: set a switch, the Internet communications management unit