Rectifier transformer is a special transformer that converts the three-phase sinusoidal AC voltage of high-voltage power grid into the multi-phase low voltage required by rectifier device, and improves the operating characteristics of AC side and DC side through the transformation of phase angle. This product is widely used in aluminum, magnesium, zinc electrolysis, salt electrolysis and other electrochemical rectification occasions. , the load level is I-II.
Product structure and working principle
Winding:
The winding of rectifier transformer is usually wound with copper wire,
It is divided into phase-shifting winding, high-voltage winding, voltage regulating winding, integral transformer high-voltage winding and integral transformer low-voltage winding, and compensation winding with compensation. Some are also attached with windings of balanced reactors or saturated reactors.
Iron core: The iron core is made of domestic or imported high-quality cold-rolled oriented silicon steel sheets, and generally adopts fully inclined non-impact drawing belt or drawing plate structure. A single 12 phase yoke ferromagnetic core can also be used. Box: welded by high-quality steel plate, divided into box cover and half bell jar corrugated oil tank structure, beautiful and high strength; Small and medium capacity, less outlet on the valve side, using the top outlet of the box cover; Half-bell type side exhaust port is used for large-capacity and multi-valve side exhaust port. In order to reduce eddy current loss, magnetic isolation measures are taken around the outlet terminal on the valve side.
Voltage regulation: according to user's requirements, use non-excitation voltage regulating switch or on-load voltage regulating switch to adjust voltage. See the instruction manual of tap changer for details.
Voltage regulation of saturated reactor: by regulating the current of the control winding of saturated reactor, the magnetic characteristics of the reactor can be adjusted, so as to make adjustment.
The reactance of the reactor can adjust the DC voltage. Transportation and lifting
Mode of transportation: Highway, railway, waterway and other modes of transportation can be selected as required. The transformer carrying oil should be filled with qualified transformer insulating oil. At room temperature, the oil level is about 100~200mm from the top of the oil tank. Check whether there is any leakage, especially the oil-free part at the top of the oil tank. When transporting with a load switch, the oil in the load switch must be placed at a distance of 100~200mm from the top of the box, or the transformer oil tank must be connected with the switch oil tank with a special connecting pipe.
Nitrogen-filled transportation Nitrogen-filled transportation transformers shall be filled with pure nitrogen with purity greater than 99.9% and dew point not higher than -40℃. Nitrogen charging equipment and pressure gauge should be installed at the top of the oil tank. Before transportation, keep the positive pressure in the fuel tank between 0.025 MPa and 0.03 MPa, and the pressure during transportation shall not be lower than 0.02MPa, otherwise, the loading and fixing during transportation shall be carried out in accordance with the relevant regulations of the transportation department. In the whole transportation process (including railways, highways and waterways), the inclination of the transformer body shall not be greater than the long axis direction; Short axis direction is not large 10
Main lifting
The foundation of lifting equipment, spreader and loading and unloading place must be able to bear the lifting weight of transformer (i.e. transportation weight).
Lifting should be carried out at the designated lifting point, and lifting and mixing should be stressed at the same time. The included angle between the sling and the vertical direction shall not be greater than 30, otherwise, the sling shall be lifted with a lifting beam. During main body traction and lifting main body traction, the traction point should be below the center of gravity of the transformer, and the wire rope should be hung on the special traction hole of the next oil tank (or the wire rope should be tied to the transformer oil tank). Do not worry about parts and pipe joints that are not stressed.
When hauling by trolley or roller, the speed shall not be greater than 100m/h, the main body shall be loaded and unloaded on the slope, and the slope angle shall not be greater than 10, and anti-skid measures shall be taken. For transformers with oil, attention should be paid to the sudden drop of the center of gravity caused by the sloshing of the oil level.
When using the jack, it should be placed under the jack bracket of the oil tank, and the number of jacks used should match the number of jack brackets of the oil tank. rise and fall
When falling, it must be synchronized and at the same speed, and measures should be taken to prevent the jack from slipping.
Parts, components and assemblies that have been unpacked for inspection shall be kept according to their performance characteristics. For sealed transportation, the sealing condition should be checked to keep the sealing reliable. Measures should be taken to prevent rain, snow and corrosive gases from directly immersing. At the same time, attention should be paid to prevent surface corrosion.
Instruments and components with electrical components (such as switch transmission mechanism, main control cabinet, etc.). ) should be placed in a ventilated and dry place, and should have
Moisture-proof measures. For transformers transported by oil, instruments and motors should be kept indoors. If it is not installed within three months after arriving at the site, the oil storage tank (including the oil storage tank with on-load voltage regulating switch) must be installed within one month, qualified transformer oil should be injected into the oil level of the oil storage tank at the corresponding temperature, and a drying respirator should be installed on the oil storage tank. Supplementary oil must be supplied from the butterfly valve on the tank cover (or oil storage tank) to prevent air from entering the body. If the oil storage tank cannot be installed in time, the upper part of the oil storage tank should be evacuated and filled with nitrogen with purity of 0.02~0.03MPa and dew point below -40℃.
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