transformer

Electromagnetic processes in transformers during their disconnection by vacuum switches

The influence of the operation of vacuum switches on the electromagnetic processes of transformers of distribution networks has been studied. It is shown that during the disconnection of transformers from the network with the connection scheme of the windings "Wye/Wye, with neutral brought out for grounding" causes significantly higher multiples of overvoltages in the windings than the disconnection of transformers with the connection scheme of windings "Delta/ Wye, with neutral brought out for grounding".

The Modes of the Power Supply Scheme of Own Needs During Start-up of the Power Units With an Additional Working Transformer

The efficiency of operation of power units of powerful thermal and nuclear power plants is largely determined by the reliability of power supply systems for their own needs. The main requirements for such systems are maintaining the required voltage level on the busbars of the distribution charters of their own needs and reduction of the time of forced power outages. Ensuring these requirements by the Ukrainian energy sector is complicated by the fact that most of its power plants are operated for a long time, and their equipment is significantly worn out.

Analysis of magnetic fields of electrical devices based on their circuit models

The article deals with an analysis of magnetic fields of electric machines and electromagnetic devices on the basis of their circuit mathematical models. The magnetic systems of electrical devices in these models are presented in the form of planar nonlinear magnetic circuits with lumped elements. The parameters of these elements are determined on the basis of geometric dimensions taking into account the design features of the devices and the physical parameters of the environment.

New directions in transformers designing

New principles of construction of magnetic systems of transformer are proposed. Selects the basic geometric dimensions of the magnetic system, which provides maximum coverage of the windings in the space as well as space-symmetric placement is achieved by improving their conditions for the occurrence of electromagnetic processes in the transformer. The result is a significant improvement in performance and new properties of transformers: automatic control of balancing stress with unbalanced load