On-site measurement of load and no-load losses of GSU transformer
Present development and production of power transformers with lower losses in addition to replacement of outdated transformers assume regular measurement of losses in both load and no-load regime. These measurements are very demanding especially in the case of on-situ measurements. The complexity of the measurements grows with the size of transformer. This paper presents one typical test of losses measuring in load and no-load regime of power transformer with nominal power of 40 MVA in HPP Perucica.
No-load loss measurements of power transformers under distorted supply voltage waveform conditions
The problem of correcting the results of no-load loss measurements of power transformers for the effect of distorted supply voltage waveform on the magnetic flux in the core and hence on both the hysteresis and eddy current loss components of core losses is presented. The instrumentation requirements for no-load loss measurements to ensure proper application of the correction formula are described.
Heat Transfer Characteristic for a New Plate Metal Hydride Reactor
The property of major metal hydride reactors in the world was analyzed and a new plate metal hydride reactor was designed.An experimental facility to test the metal hydride reactor was also designed correspondingly.The effective thermal conductivity of the plate metal hydride reactor was measured by varying the initial metal hydride packing fraction,the kind of filled gas and the pressure of the filled gas,cycle numbers.The test results show that the effective thermal conductivity of the reactor,has exceeded(7.5) W/(m·K) before activation,which is increased greatly.After alloy activation,the effective thermal conductivity of the reactor has a linear change trend with the hydrogen pressure during the interval 0.1~3.5 MPa.The effective thermal conductivity of the reactor just only decreases quickly at the beginning,but becomes stable after several cycles.