{"id":1880,"date":"2026-09-02T15:10:20","date_gmt":"2026-09-02T07:10:20","guid":{"rendered":"https:\/\/www.zishengelectric.com\/?post_type=product&p=1880"},"modified":"2026-11-09T13:56:16","modified_gmt":"2026-11-09T05:56:16","slug":"133kv-135kv-three-phase-power-transformer-high-voltage-substation-equipment","status":"publish","type":"product","link":"https:\/\/www.zishengelectric.com\/fr\/product\/133kv-135kv-three-phase-power-transformer-high-voltage-substation-equipment","title":{"rendered":"133kV 135kV Three-Phase Power Transformer \u2013 High Voltage Substation Equipment"},"content":{"rendered":"

The 133kV power transformer, also available as a 135kV design, is a three-phase oil-immersed transformer for high-voltage substations and medium-to-large transmission and distribution systems.<\/p>\n

It converts high-voltage electrical power to the required medium- or low-voltage level for subsequent distribution or industrial use. Zisheng can configure the transformer for the grid arrangement, site conditions, load characteristics and specified technical standards.<\/p>\n

The oil-immersed construction combines a magnetic core, HV\/LV windings, an oil-paper insulation system, a tank and a selected cooling arrangement. Applications include utility networks, industrial substations, renewable energy, mining and infrastructure projects.<\/p>\n

\"Oil-immersed<\/p>\n

Key Features<\/h2>\n

High-Voltage Insulation Coordination<\/h3>\n

Specify the highest voltage for equipment, AC and impulse withstand levels, neutral insulation and bushing creepage for each winding.<\/p>\n

Loss and Temperature Requirements<\/h3>\n

Evaluate no-load loss, load loss and temperature-rise limits at the stated rating, frequency and reference conditions. Guaranteed values belong in the approved technical offer.<\/p>\n

Short-Circuit Duty Review<\/h3>\n

Coordinate winding mechanical strength, system fault level, impedance and protection clearing time. The verification method is defined by the applicable standard and contract.<\/p>\n

Oil-Paper Insulation and Protection<\/h3>\n

Material selection, drying and oil processing support the insulation design. The accessory schedule defines temperature indication, pressure relief, oil level and any gas-actuated protection.<\/p>\n

Cooling and Tap-Changer Options<\/h3>\n

ONAN, ONAF and OFAF are design options rather than simultaneous standard equipment. Select the cooling-stage ratings and tap-changer arrangement for the operating duty.<\/p>\n

Construction, Materials and Main Components<\/h2>\n

The core uses grain-oriented electrical steel as specified in the approved design. Copper or aluminum winding conductors follow the order specification; neither material should be assumed from the product photograph. Solid cellulose insulation and insulating liquid provide the coordinated internal dielectric system.<\/p>\n

The main tank houses the active part. Radiators or coolers transfer heat to the surrounding air. Bushings provide insulated connections to the external circuit; their voltage class, current rating, terminal geometry and pollution performance must match the substation interface. A conservator and associated pipework are used where the selected oil-preservation system requires them.<\/p>\n

The approved bill of materials identifies valves, lifting and jacking provisions, earthing terminals, marshalling cabinet, cooling controls and protection devices. Buchholz relay applicability depends on the oil-preservation arrangement. Bushing CTs, online dissolved-gas monitoring and communication interfaces are supplied only when specified.<\/p>\n

\"Technicians<\/p>\n

Cooling and Voltage Regulation<\/h2>\n

ONAN means oil natural, air natural; ONAF adds forced-air cooling; OFAF uses forced oil and forced air. Compare the stated MVA rating at each cooling stage, available auxiliary supply, control logic and maintenance access. Do not use a forced-cooling rating as the natural-cooling rating.<\/p>\n

An off-circuit tap changer is operated only with the transformer isolated and de-energized. An on-load tap changer (OLTC) is selected when voltage adjustment during operation is required. Confirm the tapping winding, range, steps, drive supply and local\/remote control in the order documents.<\/p>\n

Information Required for Selection and Quotation<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n
RFQ item<\/th>\nInformation to provide<\/th>\n<\/tr>\n<\/thead>\n
Electrical duty<\/td>\nRequired MVA at each cooling stage; voltage and frequency of every winding; simultaneous demand, power factor, future load and contingency duty.<\/td>\n<\/tr>\n
System compatibility<\/td>\nSingle-line diagram; vector group and neutral earthing; network fault level; target impedance; existing transformer nameplate and test data where parallel operation is required.<\/td>\n<\/tr>\n
Insulation and terminals<\/td>\nHighest voltage for equipment, impulse\/AC withstand requirements, bushing creepage and terminal arrangement for each winding and neutral.<\/td>\n<\/tr>\n
Regulation and auxiliaries<\/td>\nTap range and steps, OLTC or off-circuit arrangement, auxiliary AC\/DC supplies, protection contacts and control interfaces.<\/td>\n<\/tr>\n
Site and logistics<\/td>\nAmbient temperature, altitude, pollution, corrosion, seismic and sound requirements; footprint, foundation loads, access route and lifting constraints.<\/td>\n<\/tr>\n
Acceptance and documents<\/td>\nGoverning standard and edition, inspection and test plan, witness\/hold points, report format, drawings, packing list, manuals and shipment-release requirements.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Case 1: Regional Utility Substation Retrofit<\/h2>\n

A regional utility substation retrofit brings a 133kV incoming supply onto an existing 33kV distribution bus. The load combines daytime industrial demand, evening residential demand and transferred feeders during an adjacent-bay outage. Selection starts with simultaneous demand and the required contingency operating condition, rather than the sum of feeder breaker ratings.<\/p>\n

\"Aerial<\/p>\n

The replacement unit must fit the available bay, foundation and oil-containment area. Bushing positions, bus clearances, neutral connections and transport access require a coordinated drawing review. If temporary parallel operation with an existing transformer is needed, compare voltage ratio, vector group, tap positions and impedance characteristics before approving the arrangement.<\/p>\n

\n\n\n\n\n\n\n\n\n
Engineering issue<\/th>\nConfiguration and acceptance requirement<\/th>\n<\/tr>\n<\/thead>\n
Electrical interface<\/td>\n133kV\/33kV, three-phase; project-approved MVA and cooling-stage ratings; matching vector group, earthing and protection interfaces.<\/td>\n<\/tr>\n
Voltage regulation<\/td>\nSelect OLTC and automatic control only where required; coordinate settings and parallel-control logic with the existing bus.<\/td>\n<\/tr>\n
Site restrictions<\/td>\nVerify foundation loads, terminal geometry, oil containment, crane or jacking access and the outage sequence against approved drawings.<\/td>\n<\/tr>\n
Release and site acceptance<\/td>\nRequire serial-number-linked FAT reports, inspection release and transport records; verify reassembly, fluid condition and protection operation before energization.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

\"Oil-immersed<\/p>\n

Case 2: Water-Supply Pumping Substation<\/h2>\n

A water-supply pumping substation uses a 135kV incoming connection and an 11kV motor bus. Duty and standby pumps, staged starts and service continuity govern the load schedule. The transformer rating must reflect simultaneous electrical demand, operating power factor and the agreed reserve; motor shaft power also requires the motor efficiency to determine electrical input.<\/p>\n

\"Aerial<\/p>\n

The main engineering issue is maintaining an acceptable bus voltage during pump starting and recovery after a supply interruption. Confirm the starting method, largest permitted motor start, restart sequence and interlocks. Where variable-frequency drives are used, assess harmonic current and heating with the drive supplier instead of applying a blanket transformer derating.<\/p>\n

\n\n\n\n\n\n\n\n\n
Engineering issue<\/th>\nSelection and acceptance requirement<\/th>\n<\/tr>\n<\/thead>\n
Supply and load<\/td>\n135kV\/11kV, three-phase; approved duty\/standby schedule, power factor, starting duty and MVA rating at each cooling stage.<\/td>\n<\/tr>\n
Starting and harmonics<\/td>\nReview impedance with the network and motor-starting study; coordinate drive harmonic data, starting-voltage limits and protection.<\/td>\n<\/tr>\n
Site conditions<\/td>\nPlace equipment above the agreed flood level; coordinate oil containment, earthing, cable interfaces and maintenance access.<\/td>\n<\/tr>\n
Acceptance documents<\/td>\nCheck the approved datasheet, loss\/impedance and dielectric reports, tap\/control records and installation instructions; prove the agreed pump restart and interlock sequence during site commissioning.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Cooling and tap control should support the required operating duty during hot weather and planned maintenance. The electrical designer must coordinate transformer protection with the motor feeders, neutral-earthing arrangement and site emergency operating procedure.<\/p>\n

\"Large<\/p>","protected":false},"excerpt":{"rendered":"

133kV \/ 135kV Three-Phase Power Transformer is a high-voltage oil-immersed transformer designed for substations, utility networks, industrial power systems, and large-scale transmission and distribution projects.<\/p>\n

Core, winding and insulation design are coordinated with the specified losses, temperature limits, short-circuit duty and site conditions.<\/p>\n

Custom voltage ratios, capacity, vector groups, cooling systems, tap changers, and accessories are available according to project requirements.<\/p>","protected":false},"featured_media":2685,"template":"","meta":{"themepark_post_bcolor":"#f5f5f5","themepark_post_width":"1022px","themepark_post_img":"","themepark_post_img_po":"left","themepark_post_img_re":false,"themepark_post_img_cover":false,"themepark_post_img_fixed":false,"themepark_post_hide_title":false,"themepark_post_main_b":"","themepark_post_main_p":100,"themepark_paddingblock":false},"product_brand":[],"product_cat":[71],"product_tag":[],"class_list":["post-1880","product","type-product","status-publish","has-post-thumbnail","product_cat-oil-immersed-transformer","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/product\/1880","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/media\/2685"}],"wp:attachment":[{"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/media?parent=1880"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/product_brand?post=1880"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/product_cat?post=1880"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.zishengelectric.com\/fr\/wp-json\/wp\/v2\/product_tag?post=1880"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}