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. Transformer Oil Surge Relay is a protection device for On Load Tap Changers used in Transformers. Our service range includes a wide range of pressure relief valve t-6 and oil surge relay for transformer. According to the structure of on-load tap changer provided by the actual converter station and the field measured results, the separation process of the dynamic and static contacts of the main contact and transition contact is finally determined as follows: 1) During the switching process, the main contact quick mechanism rotates a total of 28° (14° on one side), and the rotation angle of its moving contacts during the separation of the moving and static contacts is 26°. Fusion Energ 37, 346–353. For example, Xu et al. Rivas-Trujillo, E., Laniado-Jácome, E., San-Román, J. L., and Díaz, V. (2010). C) Variation curve of oil flow and oil pressure with total arc energy.
What is the difference between OSR and BUCHHOLZ relay of transformer? Offered range is used to protect the malfunction developed inside the on load tap changer. Buchholz relay is gas directed relay that is motivated by the gases moving through and assembled in buchholz relay, whereas oil surge electrical device is actuated when the oil flow-rate is exceeded by the preset value. UV Proof pure polyester powder coated body. When a sudden surge of oil happens, the trip contact is activiated, this activation of the trip contact can be utilized to switch of the OLTC and prevent further damage. When a slight or incipient fault occurs within the transformer, the gas generated will collect in the top of the relay housing. Types of OSR relay: - OSR with mercury switch (Increase of bucket types relay).
The dielectric strength of the oil is the most important property of oil. In the event of serious oil loss from the transformer, both alarm and trip elements operate in turn, in the manner previously described for gas collection. Among that, the right part is the in port of oil flow, and its pipe extends into the changer cylinder for 1. We also manufacture Oil Surge Relays for protection of O. L. T. C. Transformer Buchholz Relay. Since the gasification of transformer oil caused by arcing is not considered in the simulation, the actual oil flow velocity should be higher than that of the numerical simulation, so it is necessary to consider increasing the setting value of oil flow relay. The complete tap changing process is shown in Figure 2, which includes two arc extinguishing processes (in step d and step f, respectively), and the breaking current, recovery voltage, and switching capacity of the two arc extinguishing processes are shown in Table 1. The particularity of the operating conditions of the commutator tap changer is revealed, and the technical points of the selection of the commutator tap changer are proposed (Lei et al., 2018; Fan et al., 2018).
Buchholz Relay Advantages and Disadvantages The following are the pros of Buchholz relay. If a fault occurs in the transformer, a pressure wave (surge) is created in the oil. Silica gel Dehydrating Breather: The silica-type breather is used for drying the air drawn into the oil conservator when they drop in load and temperature causes the oil to contract. Keeping in sync with the latest market norms and policies, we are indu... This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). In HI POT test what is reason for applying the AC VOLTS and DC VOLTS in different applications what is the nessesity for this? Side entries and alternative thread sizes can be supplied for most types upon request. We are a big name that deals in the manufacturing and supplying of heavy-duty Oil Surge Relay (OSR) that is used as a safety unit for the protection of internal faults within tap changer circuits. To ensure this the oil has to be tested and if any change in parameters observes, it has to be either replaced or oil filtration is needed. Therefore, all structures outside the diaphragms are removed during modeling. Figure 33 – Buchholz Relay, Section. In addition, an equivalent experimental platform is built to carry out the static action characteristic experiment of OLTC oil flow relay, the corresponding relationship between the change range of oil pressure at the top of the chamber, and the oil velocity under typical value (1. This relay can detect only when the oil level is below.
Hence only single float is provided in the OSR connected to OLTC to avoid unwanted interruption of supply to the Transformer and ensures safety tripping when any internal fault occurs or low oil level condition in the OLTC tank. The temperature difference in the whole cylinder is very small, only 1. The corresponding transport equation is: where. We have manufacturing facilities in two cities and dozens of global distributors and warehouses with whom we can ship to any country in the world. A heavy fault inside of the OLTC incidentally generates pressure wave or Oil surge or Oil move in the direction of OLTC tank. The trip element will be operated by an oil surge in the event of more serious faults such as: The trip element will also operate if a rapid loss of oil occurs. The correlation coefficient between oil flow and oil pressure is 0. The test principle is shown in Figure 12. During this test the relay was vibrated to an. Relay Type: Oil Surge Relay. Experimental Study on Heavy Gas Setting Value of Domestic on Load Switch for Large Capacity Transformer. Apart from low oil level condition, upper float acts when gasses accumulate due to minor internal faults in the Transformer and lower float acts when sudden rush in oil towards to conservator tank is sensed due to major internal faults in the Transformer. 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. 76 rad/s; in the contact stage, it rotates 12°, and its angular velocity is 76.
No need to treat for porosity, since no microcracks are developed. The oil pressure on the cylinder wall changes little, about 100. In this article, in Section 2, the mathematical simulation model of OLTC is established; in Section 3, the simulation result is analyzed, and besides the experimental method, the result is proposed; the change law of the oil speed and oil pressure at the top of the chamber when the OLTC operating under different transition resistances is analyzed, so as to provide guidance for the OLTC protection configuration. Lei, Y., Zhao, L., Peng, Z., Bao, L., Yang, J., Zhang, X., et al. Testing of the dielectric strength of the oil is normally conducted on-site to get a quick check of the purity of the oil. This unit functions by triggering the tripping circuit in the case when oil flow exceeds the specific levels.
The connection pipe and relay cover should have 1. Therefore, taking the typical dual-transition resistance-type OLTC as an example, a numerical modeling method of OLTC oil flow surging based on the realizable k-ε model is proposed, and the fluid simulation model is established based on the FLUENT software. Product Price: Rs 8, 500 / UnitGet Best Price. Viat supplies to over 500 transformer OEMs in 70 countries and is widely approved by utilities and OEMs globally. The oil level in the double element relay can be monitored against a graduated scale on the windows both sides. The flow rate at which the paddle activates the. The process from contact to separation is the opposite.