Study On Oil Flow Surging And Protection Optimization For On Load Tap Changer Of Converter Transformer

Thursday, 11 July 2024

The switches of the contacts stopped and an alarm circuit strengthened. According to OLTC stage voltage and rated current, AC arc energy during switching can be calculated by: where, The main contact and transition contact of the OLTC are swing rod devices with one end fixed, then the value of. The energy generated during tap switching process of the OLTC will cause thermal expansion and surging of the insulating oil in the chamber, resulting in the mis-operation of protective relay and threatening the safe and stable operation of the power system as well. A heavy fault inside of the OLTC incidentally generates pressure wave or Oil surge or Oil move in the direction of OLTC tank. Authors HZ, ZX, and JD were employed by the company Extra-High Voltage Transmission Company of China Southern Power Grid. Switching Process Simulation and Type-Selection Technology of On-Load Tap Changer of Converter Transformer.

Oil Surge Relay In Transformer Prime

In terms of OLTC operation characteristics analysis, electromagnetic transient simulation research has been carried out for the switching process of the OLTC, and quantitative analysis has been obtained from the two aspects of amplitude and phase. So, Let me interpret the major differences between them. 56, New Satguru Nanik Indl. 3 Setting of Arcing Time, Arcing Position, and Released Energy. Additional Information: Item Code: SO-4. Exclusive Features of our Buchholz Relay & Oil Surge Relay: Body is made of single piece die-cast aluminum alloy instead of casted CI body, in which microcracks may give leakage at any time. As gas bubbles migrate along the pipe, they enter the Buchholz relay and rise into the top chamber. Jaycoach, Goregaon East Mumbai Maharashtra India +918037304187. A definite cause of the gas bubbles must be determined and corrected before re-energization of the transformer. B)Model of the auxiliary contact and its fast mechanism. When the rate of rising pressure oil crosses a certain value then alarm and trip contacts operate. Now Enjoy lighter and faster IndiaMART Lite on the go! Buchholz Relay Working Principle The Buchholz relay working principle and operation is very simple.

Ref Relay In Transformer

Figure 33 – Buchholz Relay, Section. Thorne & Derrick stock and distribute an extensive range of Transformer & Switchgear Equipment for use in LV MV HV Substations including Porcelain Bushings | Bushings MV HV | DIN Bushings | Resin Bushings. This relay also serves a third function, similar to the sudden pressure relay. It is basically to save the Transformer from getting damaged due to any fault in the OLTC chamber. The oil level in the double element relay can be monitored against a graduated scale on the windows both sides. In the process of switching, when the moving and static contacts are separated from contact, the main contact and transition contact not only rotate with their own rapid mechanism but also rotate around their own rotating shaft under the action of the spring at the bottom of the contact. This unit functions by triggering the tripping circuit in the case when oil flow exceeds the specific levels.

Oil Filled Current Transformer

Transformer Oil Surge Relay. Exclusive Features of our Buchholz Relay: Microcracks may give leakage at any time. Predominate and rotate the whole system until it reaches the top stop, with the Mercury switch in the open position. The updating process of the mesh is completed automatically according to the change in boundary at each iteration step. 87, respectively, showing a negative correlation. Available Pipe Diameter. The least operating time of the Buchholz relay is 0. The contact process of dynamic and static contact of transition contact. The on-load tap changer (OLTC) is one of the key components of converter transformer. Complete range for pipe diameter. However, it can only modify the protection setting value based on experience to deal with the mis-operation case, due to a lack of mechanism research (Liang et al., 2016).

Oil Surge Relay In Transformer Formula

Therefore, the connecting rod mechanism is removed during the modeling, The motion equation of the main contact, the transition contact and the fast mechanism are comprehensively determined according to the contact structure of the dynamic and static contacts, the structure of the fast mechanisms, and the current change law in the switching process, such that it can simulate the motion of the moving contact and its fast mechanism in the switching process. 413 rad/s; in the contact stage, when the fast mechanism of the transition contact rotates by 1°, the moving contact rotates by 2° around its own rotating shaft. Keywords: on-load tap changer, fluid simulation, oil flow surging, protection optimization, transformer.

Sudden Pressure Relay In Transformer

The relay should be mounted in the connecting pipe between the transformer and the conservator tank. Therefore, we can obtain the reliable operating pressure range of the above three oil flow relays, that is, the oil pressure range of the three oil flow relays (1. 42°, that is, when the fast mechanism of the main contact rotates 1°, the moving contact rotates 4. Actually, there have been many cases of relay malfunctions, especially oil flow velocity relay. Select different T1, T2, and T3 to simulate the changes of oil flow speed and pressure in the oil chamber of the transfer switch when the on-load tap changer is switched under various combinations, as shown in Table 4. The grid at the contact between the moving and static contacts of the main contact and the transition contact has been densified. Contact us for information regarding our sample policy. Figure 8 shows the overall grid of the OLTC. 5 mm, and the grid of the adjacent surface is set to 1 mm; for the quick mechanism of the main contact and transition contact, the face grid adjacent to the main contact, transition contact, and rotating shaft is set as 2 mm, and the other face grids are set as 4 mm; for the switch base, the face grid adjacent to the rotating shaft is set as 2 mm, and the other face grids are set as 4 mm; for the transition resistance, since the distance between the resistance and the isolation plate is 5. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors, and the reviewers.

The flow field of oil chamber is simulated by realizable k-ε model (Wang, 2004; Wen, 2010), which is improved based on the standard k-ε model, that is, the k equation remains unchanged, while the equation of dissipation rate ε and the eddy viscosity equation are improved mainly. The generation term of the dissipation rate ε in Equation 5 (the second term on the right) does not include the turbulent kinetic energy. The process from the initial separation position to the contact is opposite to this process.