RESULTS of the Vth All-Russia Conference "Development and Reliability Improvement of Distribution Networks"
(July 2-3, 2019, Moscow)
The Conference has been organized and held by PJSC "ROSSETI" and personally by Andrey Vladimirovich Mayorov, its Deputy Director General, Chief Engineer. Co-organizer - JSC "United Energy Company" (JSC UNECO), business program partner — "ELECTRIC POWER. Transmission and Distribution" journal.
The event has been dedicated to aspects of development and operation of MV (0,4-20 kV) distribution networks, in particular:
- digital transformation of distribution networks;
- key aspects of 20 kV network development;
- live work in 0,4 kV and 6-35 kV networks;
- sharing experience on hot issues, review of international practice.
Event Status: visiting session of International Forum "Power Grids" (PGIF-2019).
Participants: above 300 persons, including representatives of the Ministry of Energy of Russia, top managers and specialists of the Russian power grid (Rosseti Group, major regional grid companies: JSC Yugorsk Electric, JSC UNECO, JSC Mosoblenergo, JSC Oboronenergo, OJSC Grid Company (Kazan), etc.); experts of oil & gas companies, scientists of the Russian Academy of Sciences, higher educational establishments, experts from design companies, representatives of industrial companies - power equipment and material producers (according to the list).
On completion of discussion the participants of the Conference have come to the following conclusions:
- Distribution networks hold the great potential to improve operation reliability by using modern, including digital, technologies. In particular, a future-proof solution for metropolitan networks is transition to 20 kV voltage level with resistive neutral grounding. This needs application of IT solutions with regard to protection and online process control arrangement.
- The first step to digitalization should be introduction of IT solutions in monitoring and management systems of a grid company: transition to digital networks and substations, digital operating parameter measuring systems, condition monitoring of equipment and transmission lines, protection and emergency automation, and others.
- Digitalization of power transmission processes will fundamentally improve grid company's current business processes and establish new ones like optimized asset management, improved human resources management, new services (tariff menu, connection of small distributed generation, infrastructure for charging stations, etc.).
- With regard to stipulations of the concept "Digital transformation 2030", the draft of reviewed Uniform technological policy in PJSC "ROSSETI" power grid has been developed. Strategic trends and the content of such reviewed Uniform technological policy comply with advanced world trends and is aimed for implementing objectives of the Strategy of Russian Federation power grid development, functions and objectives of PJSC "ROSSETI", measures on digitalization of technological and production processes of Rosseti Group, provision of efficient set of technical, technological and organizational requirements and solutions to improve efficiency, reliability, security, profitability of power transmission and distribution.
- In the nearest future it's highly probable that approaches to grid company's capitalization will be re-estimated. In digital economics environment it will be defined not by the total of production funds, but by the company's efficient management system that can be localized to different client and external contractor requests.
- Due to automation and improved observability of the network it becomes possible to reduce the response and recovery time in "digital regional power grid" projects from 5 to 2 hours in average. In some cases automation and digitalization of grids by means of installing reclosers help to optimize capital costs of a grid company, to avoid construction of additional transmission lines - this is particularly true in constraint environment and hard-to-access locations (forests, swamps, high-density development, etc .).
- Introduction and mastering of "digital electrician" technologies will contribute to mobility of crews. Technical information (diagrams, regulatory documents, procedures, instructions) duly available at the work site, improved quality of routine, unscheduled and emergency response works, reduced labor costs for analysis of detected failures, thorough planning of technical maintenance and repair program, electronic data processing will help to improve the working hours efficiency into 20%. From the consumer's point of view, a very important consequence will be high reliability - at least 15% plus to reliability level and the supply restoration time. Due to improved efficiency of management and monitoring of personnel (mobile crew) movements and actions, avoiding non-productive activities, electronic switch cards with switching sequence monitoring, rate of personnel injuries can be reduced into 20%.
- Experience of introducing hybrid digital data transmission networks shows that such technologies enable major breakthrough with regard to available services and automation of operative dispatch control system (introduction of OMS/DMS), increase of communication infrastructure security and reduced average costs of network arrangement and operation.
- Over the last years Russian grid companies have obtained profound experience in construction of 20 kV distribution networks in different load density conditions, climatic zones and technical solutions implemented (see details in Conference reports).
- Investigations carried out by Rosseti Moscow Region have shown that economical effect of transferring to the diagram with multiple low power pole-type transformer substations installed close to house and grounds is achieved if only the number of connected current collectors is at least 32; the average annual capacity of current collectors should be at least 4,7–5 kW.
- Main factors affecting operation reliability and security of a 0,4–20 kV overhead line with self-supporting insulated wire in construction and acceptance at the contractor's are as follows:
– Mandatory incoming inspection in construction of a 0,4-10 kV overhead line with self-supporting insulated wire;
– Quality of overhead line accessories: banned use of counterfeit accessories for self-supporting insulated wire.
The ways of getting copies and counterfeit accessories for self-supporting insulated wires: dealers, structural contractors of 0,4-10 kV overhead lines with self-supporting insulated wires, companies that perform connection to an overhead line with self-supporting insulated wire within the project scope.
- Main factors affecting operation reliability and security of a cable line in construction and acceptance at the contractor's are as follows:
– Mandatory incoming inspection of main cable equipment (cables, joints) and accessories (ducts, manholes, transposition boxes, etc.) coming to construction sites;
– Performance of commissioning testing of cable lines;
– Application of equipment and materials that help to detect and localize cable damages before it is put into service.
- Undertaking live work by grid companies will sufficiently improve reliability, reduce damage from power undersupply and the number of consumer claims on unsatisfactory service delivery.
- In the process of implementing the Concept of digital transformation, development and reliability improvement of distribution networks, grid companies face a lot of problems. Very often their solution requires action synchronization and sharing experience between different proprietors and harmonization of regulatory technical base. Therefore, it is advisable to hold All-Russia research and technical conference "Development and Improvement of Operation Reliability of Distribution Networks" annually.
On completion of discussing reports the grid companies get the following recommendations:
- To accept and carry out the concept "Digital transformation 2030" developed by Rosseti Group and the draft of reviewed edition of the Uniform technological policy in the power grid. To launch "Digital Regional Power Grid" and "Digital Electrician" projects.
- To pay more attention to introducing such advanced technologies and tools like digital alter ego and digital shadows, to consider possible increase of process automation, robotics, 3D printing technologies, etc. To optimize process flows and financial expenses by applying digital technologies that describe module-based solutions.
- To pay special attention to cyber security and digital data safety issues when integrating advanced digital solutions.
- To take into account and, if supported by feasibility study, to make use of the experience of 0,4-20 kV distribution network construction and results of pilot projects specified in reports of Conference participants, including:
– network construction diagrams with 6-10/0,4 kV low capacity pole-type transformer substations installed close to consumers and 0,95 kV networks;
– composite towers for 0,4-10 kV overhead lines;
– vibrated reinforced concrete racks for 0,4-10 kV lines similar to series СВ-95, СВ-110, made of high weight concrete modified by carbon nanotube dispersion;
– anchor steel multi-sided towers for 0,4 kV lines;
– new generation conductors (with cores made of steel and aluminium alloys or composite non-magnetic materials, with cylindrical surface made of trapezoidal, z-shape or other wires with less aerodynamic drag factors);
– multi-chamber insulator arrester based on the pin porcelain insulator ИРШФМК-10(-20);
– energy storage systems;
– 10 kV substations of underground and embedded design;
– methods and means of fault location detection in 6-10 kV overhead transmission lines;
– 35 kV prefabricated tower for carrying out emergency response and restoration works.
- Provide reliability and security of a 0,4-20 kV overhead line with self-supporting insulated wire and cable lines in construction and acceptance from contractors, purchase of other electromechanical products and electrical safety devices to observe the following principles:
– To include technical specialists having a deciding (not consultative) vote into tender (purchase) commissions.
– To precise purchasing documents to set priorities for high quality products.
– To perform sample acceptance of sites implemented by contractors together with representatives of Customer, Contractor and Manufacturer.
– Approved manufacturers should provide the set of original products for possible checking.
– When performing the works on own, participation in purchase within the scope of energy service contracts, to admit only certified manufacturers or manufacturers that provide the complete set of testing protocols for compliance with company's standards performed by an accredited laboratory.
– Within the scope of a tender application to provide the manufacturer's letter on guarantee obligations, with indication of the country of origin of products, manufacturer trademark, specific construction site.
– Oblige contractors to get certificates in training centers to observe wiring technology.
– To prepare proposals on formation of the uniform list of counterfeit product suppliers.
- Consider application of mobile step-up transformer substations for different power ranges to provide sustainable power supply of consumers during emergency response and restoration works.
- To consider possible live works such as replacement, leveling of towers on a 0,4 kV overhead line, replacement of an insulator, a protective cap, a tie-in, adjustment of deflection in a 0.4 kV overhead line, replacement of a 0,22-0,38 kV tapping from a 0,4 kV overhead line, revision of contact joints, double grounding wiring, execution of requests of sales companies, connection of new consumers. Requirements of Rules of occupational health and safety in electric installation operation should be strictly observed.
- To consider the draft of the Standard "20 kV network of a metropolitan city. Norms of technological design" prepared by JSC UNECO together with JSC "Institute Energosetproect". Provide proposals and supplements to the document.
- To share experience with foreign experts, increase the number of major international events that Russian specialists participate in, like regular CIRED conferences.
- To share experience between Russian specialists with regard to development and improvement of operation reliability of distribution networks, send proposals on topics and issues for discussion and adding to the agenda of VIth All-Russia Conference "Development and Improvement of Operation Reliability of Distribution Electric Networks" on June 30 — July 1, 2020, to the Conference organizers.
- Review of the Vth All-Russian Conference "Development and Reliability Improvement of Distribution Networks" from the "ELECTRIC POWER. Transmission and distribution" journal
- Program of the Vth All-Russian Conference "Development and Reliability Improvement of Distribution Networks"
- Photo report: Vth All-Russian Conference "Development and Reliability Improvement of Distribution Networks"