35KV-66KV Oil Immersed Power Transformer
1. Scope of application
35KV-66kV series oil immersed power transformer has optimized design using advanced technologies, in order to offer low noise, low loss low partial discharge, high short circuit withstand capability. Advance design software are used for electromagnetic calculation and design of transformer, while 3-D,2-D CAD software for structural design ensure sufficient safety margin during short circuit period. This is based on in-depth theoretical and experimental studies on magnetic, thermal, mechanical strength and short circuit strength. To ensure reliability of the transformer, the insulation are decided based on calculation on main and vertical insulations. The accurate calculation of the electric filed distribution in inner coils will ensure voltage gradient and at coil end it will ensure low partial discharge.
2. Product standards
GB/T1094.1-5 GB/T1094.7 JB/T10088 GB/T6451
GB/T7595 JB/T3837 GB20052 IEC60076
3. Operation environment
1) Altitude: ≤1000 meters.
2) Ambient temperature: Maximum +40ºC, Minimum -40ºC.
3) Max outdoor wind speed: ≤45m/s.
4) Max Ground ramp degree: ≤3°.
5) Seismic level: ≤3m/s2 at horizontal direction and ≤1.5m/s2 at vertical direction.
6) Installation environment: No obvious and heavy pollution, no explosive and corrosive gas and dust, with good air ventilation and no severe vibration and shock.
7) If the application environment is different from the above standard conditions, please contact for customized designs.
4. Product advantages
1) Potential distribution is effectively improved by application of software to calculate the impact and gradient potential distribution. The potential calculation is also done between various parts of the coil including between the coil and earthing.
2) Low loss
Correctly control the radiation of leakage flux into various parts of transformer on the base of calculation of the magnetic flux leakage in order to adopt corresponding measures to effectively reduce the stray loss, and in the mean time effectively prevent local overheating to control equilibrium temperature rise, lower temperature rise of winding hot spots. Application of electromagnetic optimizing design software to optimize the design of core and winding.
3) High resistance to short-circuit capacity
Apply transformer resistance to short-circuit capacity accounting software to design HV winding and LV winding. HV winding will be designed as central outlet, up and down parallel connection with axial oil path; the regulating winding will be designed as central outlet in the middle of HV winding with up and down parallel connection to improve transformer short-circuit resistance.
4) Low noise
Lower the noise level by choosing high quality steel core material; right flux density and the self-vibration frequency of the core; application of high resistance to short-circuit of the body structure; and improving the connection method of tank and active part.
5) Low temperature rise
Apply reasonable oil flow distribution structure by calculation of oil flow distribution; reduce the winding hot spot temperature rise and the average temperature rise in order to increase overload capacity of each part, extend the life of transformers.
6) Low partial discharge, extend transformer service life.
6.1) Analytical calculation of electric field to improve the electric field concentrated region.
6.2) The way of vacuum oil filling, effectively prevention of formation of air bubbles inside the transformer and insulation parts to reduce partial discharge.
