Hot line operational bypass system
Considering the increase of equipment lifetime in installed lines in the urban electricity distribution network and development of these lines, which are not easily accessible, the necessity of equipping a system with the ability to be replaced in the condition of repairing or preventive maintenance (PM) in overhead networks, is strongly felt.
Thus, Kian Transfo, according to the proposal of Mashhad Electricity Distribution Company experts, started to design and manufacture all parts of medium voltage equipment along with functional quickly installed connections to provide power supply without blackouts to the subscriber. This system is a bypass system and a temporary replacement for overhead power transmission lines with hard accessibility.
In this situation, it is necessary to have a vehicle that has minimum weight and dimensions, which not only has a high speed in transportation, but also has complete protection equipment for sensitive and emergency loads that cannot be interrupted for a long time.
Therefore, the bypass system has been designed, built and ready for operation from the dispatching center with the possibility to monitor the status of the switches and the network.
Advantages and Applications:
- Temporary replacement of the main line and branches in order to prevent the power loss to the subscribers connected to the medium voltage line during the PM,
- Branching capability along the bypass path for transformers installed in the path or network junctions through two-way, three-way and four-way junctions,
- Possible to monitor the status of the switches and also observe the project operation by CVR on the dispatching system (current level),
- Possible to connect overhead networks and branches in 6 points,
- Possible to increase the length of the bypass route using 200 meter cables,
- Easy transportation of the maneuvering system switch box to different places,
- Quick installation of cables according to the covers designed by Kian Transfo Company.
Temporary electricity supply system for subscribers in emergency situations (Mobile Substation)
Considering the increase of equipment lifetime in installed lines in the urban electricity distribution network and development of these lines, which are not easily accessible, the necessity of equipping a system with the ability to be replaced in the condition of repairing or preventive maintenance (PM) in overhead networks, is strongly felt.
Therefore, according to the proposal of Mashhad Electricity Distribution Company experts and in cooperation with Kian Transfo Company, the design and manufacturing of modular and mobile equipment got started, which includes all parts of medium voltage and low voltage equipment along with functional quickly installed connections to provide power supply to the subscriber.
This system is used as an emergency substation and a temporary replacement for fixed pad mounted substations such as full-oil, gas-oil, gas and oil switchgears, kiosks and distribution transformers with hard accessibility.
Advantages and Applications:
- Temporary replacement of all types of compact substations, switchboards and kiosks that are damaged in emergencies, in which maintenance is time-consuming and it is not easily accessible to repair.
- Providing temporary electricity to subscribers or sensitive projects, as well as increasing the network capacity temporarily (in the shortest possible time)
- Increasing the speed of replacing or moving the damaged equipment of the distribution networks quickly, by using pre-planned trailers, especially in cases where the damaged equipment is not in a suitable place and it is not possible to use a crane and forklift.
- Changing the wheels of ground transformers using hydraulic jacks pre-planned at the location as quickly as possible.
- Establishing a ring of double-feeder plug-in cables in order to bypass and remove the substation temporarily, especially in faulty RMUs.
Medium Voltage Switch Bypass Operation System
Due to the need to increase the lifetime of the equipment of the substation installed in the urban electricity distribution network and extending of these substations, which are sometimes not easily accessible, the need for a bypass power system in preventive maintenance conditions is always felt. Therefore, suggested by Mashhad Electricity Distribution Company experts and in cooperation with Kian Transfo Company, the design and manufacturing of modular and mobile equipment was started, which includes all parts of medium voltage and low voltage equipment along with functional connections to provide a quick link for power supplying to the main board entry of substation.
This system must be highly flexible and have the ability to connect to all types of indoor overhead substations available in the kiosk network. On the other hand, there must be the necessary protections in the system during operation to prevent any fault cost in the network and avoid equipment damages. These protections will cover the connections of the mobile substation for the temporary power supply.
Advantages and Applications:
- Medium voltage switch bypass for hot-line during maintenance
- Provision of temporary medium voltage electricity for subscribers or large projects in a limited time
- Quick operation to bypass and repair damaged equipment, especially in cases where it is not possible to use heavy equipment such as cranes and forklifts due to the poor accessibility of the place.
- Setting up a two-feeder ring in order to temporarily bypass the power supply during the substation repair.
- Mobile and minimum dimensions according to the space limitations of the MV switchgear
- Possible to add dispatching equipment to the substation, such as possibility to view the incoming and outgoing current, possibility to install a CVR camera and the status of the substation switch.
15 MVA, 63/20 KV High Voltage Compact Substation
According to increasing the use of electricity in the world and based on dependence of most industry performances to this kind of energy, supplying consumers' energy requirement is a major priority and duty of the electricity industry for all countries around the world. Due to land required for construction of high voltage conventional substation, the idea of designing and producing the equipment with the minimum dimensions was proposed and became operational.
Also the first high voltage compact substation in the world with the range of 15 MVA, 63/20 KV is installed in a site of 40 m².
A brief introduction of the high voltage compact substation:
In addition to designing and manufacturing procedures and with considering technical issues in these high voltage equipment, finding and determining a suitable site for placing and installing the equipment is a challenging point that must be considered (specially with the importance of land price in big cities). Due to this adorable reduction of compact substation dimension, the use of this type of high voltage equipment in the cities can have a significant budget saving in land cost.
Decreasing installation and commissioning cost and saving time for connecting mentioned equipment to the network are some other advantages of using this kind of modularized high voltage equipment.
It should be noted that the mentioned equipment is entirely made in Iran and we are proud to say at this point that all main parts are produced and assembled in Iran.
The main modules of this equipment, including 63 KV GIS incoming equipment module, transformer module and 20 KV switchgear are connected together through the special high voltage and mid voltage connectors.
One of the most important ideas in this project is about placing all equipment including the main transformer, auxiliary transformer, earthing transformer and all measuring equipment in one module to reduce these equipment distances in order to optimize final substation dimension.
A brief information about different parts of substation:
- 63 KV incoming and 63 KV current transformer.
- 20 KV outgoing and related circuit breaker.
- 2‐position and 4‐position switches for testing equipment such as main transformers, auxiliary transformers, current transformers, etc.
- Control panel, internal power supply, protection equipment and cooling systems.
- 110 V Battery room and charger.
- Monitoring devices such as oil level and oil temperature indicator, winding temperature indicator and Buchholz relay.
- HVI/RTU for sending data to the dispatching center.
- Terminal box for measuring equipment (20 KV current transformers and potential transformers).
Advantages and benefits:
- Reduction of the required site dimension by removing all control room, monitoring devices and 20 KV switchgear,
- Reducing network losses with the ability of installing equipment near the main load,
- Controlling and monitoring all data (including all digital and analogue signals) using SCADA and no need to have operators with designing special RTU (with one‐third dimension compared with other common substations),
- Paying special attention to tank designing to be corresponded with the surrounding environment,
- Increasing operator’s safety,
- Faster and easier installation and operation compared with common substation (specially in high‐density urban areas),
- Installing all control panels, protection devices, internal power supplies (AC / DC), battery charger and SCADA on the main tank and locating all required ventilation devices during peak load,
- A significant reduction in cabling distances with omitting the control room,
- Unaffected by environmental pollution and climatic factors,
- Considering all safety requirements for network operators and using Iranian protective relays,
- Reducing used concrete volume in concrete casting compared with popular substation foundation,
- Removing all clamps, connectors and insulators between the main and auxiliary transformers,
- Compatibility of transformer module with GIS switchgear with consideration of easy cable connection.