In addition to contributing to the stable supply of power, regular inspections of T&D facilities are essential to prevent the future accidents and damages. We offer a variety of inspections utilizing our knowledge of equipment and experience as maintenance specialists. From planning to execution, we also offer total support for the early detection of signs of the degradation and for maintenance decisions on the timing of repairment or renewal of deteriorated equipment.
Gas Insulated Switchgear (GIS)
Transformer
Switchgear/Monitoring Equipment
Electricity is created at power stations, transmitted and distributed to consumers (factories, buildings, homes, etc.). These points are substations and switching stations, and substations handle the receipt, conversion, distribution, and supply of sent electricity under one roof. Here, GISs and other switchgears are important equipment to quickly intercept and minimize damages from unforeseen circuit incidents. As GIS is so complicated through high voltage or high pressure gas, regular inspections and repairment need specialist usually. Hitachi Power Solutions can offer precision inspection services that meet customers' needs.
We suggest items for inspection corresponding to customer requests.
Example of Items for Inspection
Checking for abnormal odors, abnormal sounds, pressure gauges, opening/closing indicators, and fault indicators
Visual inspection (tanks, cases, generating line piping, insulators, etc.)
Visual inspection and cleaning of the interior of operation cubicles
Visual inspection and testing of operation mechanisms, links (springs, operating rods, etc.), and lightning guards
Testing of gas density detectors, and various other measurements/tests
Example of Items for Inspection
Greasing up of operating mechanism and links (springs, operating rods, etc.)
Inspection of circuit breakers, disconnectors and earthing switches
Measurement of moisture content in SF6gas
Testing of opening/closing characteristics of circuit breakers
Replacement of parts
We flexibly respond to the specifications and requests for customer equipment.
Part Replacement
Cubicle insulation
Gas pressure gauges, gas monitors and sensors
Voltage detectors
Support switches, support relays
Closing and trip coils
Disconnecting Switch/Earthing Switch actuator parts
Dash pots (overhaul or part replacement)
Replacement of window packing
Replacement of gas pressure gauge
Replacement of disconnecting switch actuator
Deterioration and cracks in insulating materials (bushings and spacers) used in gas insulated switchgears, etc. are some of the problems that are difficult to discover in regular inspections. This is because these defects in the bushings and spacers are hard to discover visually. Ultrasonic flaw detection technology is effective in the early discovery of these defects. Utilizing this technology, we contribute towards the prevention of equipment accidents and operation shutdown by diagnosing internal integrity from the reflected waves and discovering separation, cracks, and other abnormalities early.
Because electricity is sent from power stations at a high voltage, we need to convert this high voltage to an appropriate lower voltage for consumer use. Transformers are used to convert power voltage to lower or higher voltage at some substations and are requested to have a service life of 50 - 70 years. Planned inspections and repairment are important to allow for stable use of transformers and to prevent accidents and damage. We propose and offer a variety of inspection and repairment services for stable operation, based on our experience.
We suggest items for inspection corresponding to customer requests.
Example of Items for Inspection
Checking for abnormal sounds, compound pressure gauges (pressure gauges), thermometers and oil gauges
Checking for abnormalities with pressure discharge equipment
Checking for the presence of oil leakage
Visual inspection of main circuit terminal and bushings (looseness, discoloration, damage, etc.)
Visual inspection (looseness, discoloration, damage, etc.) and internal cleaning of junction boxes, lead piping, live oil purifiers and electrical operation equipment
Analysis of gas in insulating oil
SF6gas analysis (SF6gas insulated transformer)
Example of Items for Inspection
Oiliness analysis, furfural analysis (as necessary)
Remaining life estimation analysis
Inspections of electrical operation equipment
On-load tap changer inspection
Replacement of cooling fan bearings
Replacement of gas circulation blower (SF6gas insulated transformer)
We flexibly respond to repairment and replacement of parts.
Switchgears refer to cubicles and switchboards that are equipped with circuit breakers and disconnectors for opening and closing circuits, meters for measuring voltages and currents, and protection devices for detecting abnormalities. For switchgear's stable operation, we offer repairs in addition to detailed inspection including replacement of aging parts after consultations with the customers.
We suggest items for inspection corresponding to customer requests.
Example of Items for Inspection
Checking for abnormal smell, noise, overheating , discoloration, etc.
Checking the meters, protective relays (appearance), fault indicators, counters
Visual inspection and cleaning of the entire panel, main circuits, support insulator, visual inspection of disconnectors and load switches ,inspection and operation test of mechanical parts.
Inspection of vacuum circuit breakers
Characteristic test of protective relays
Example of Items for Inspection
Parts replacement for the aging devices inside the panel
Inspection of built-in devices (Vacuum circuit breaker, etc.)
Opening/Closing Characteristic Test (Timing Test)
Example of Items for Inspection
Visual inspection of monitoring equipment
Measurements of power supply voltage, inspection of wiring
Replacement of parts and computers
We flexibly respond to repairment and replacement of parts.
Protective relay
Air circuit breakers
Fuse
