The more sophisticated a protection algorithm, the more information on both steady-state and transient behavior of a protected element required for proper designing, setting and testing of a given relay. In the case of a power transformer, the most important phenomena to be modeled from the standpoint of protective relaying are: magnetizing inrush including initial, recovery and sympathetic inr...

In flammable or explosive environments, an ultrasonic sensor for distance measurement poses an important engineering safety challenge, because the driving circuit uses an intermediate frequency transformer as an impedance transformation element, in which the produced heat or spark is available for ignition. In this paper, an intrinsically safe ultrasonic ranging sensor is designed and implement...

The reliability of smart substations has a great significance on the safety and stability of smart grid operation. Taking the protection system in smart substation as an example, this paper constructs comprehensive reliability models to evaluate the reliability of smart substations with different architectures. The paper first illustrates two important aspects which affect the reliability of th...

It is an effective measure for power enterprises to improve the voltage level of system by raising and lowering tap position main transformer. For parallel operation transformer, whole process adjusting must strictly meet conditions operation. Aiming at a case backup protection action transformer caused improper implementation regulation measures, this paper analyzes uneven load distribution in...

A distribution system was designed and operated by considering unidirectional power flow from a utility source to end-use loads. The large penetrations of distributed generation (DG) into the existing distribution system causes a variety of technical problems, such as frequent tap changing problems of the on-load tap changer (OLTC) transformer, local voltage rise, protection coordination, excee...

This paper deals with permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS) integrated with grid with two back to back connected converters with a common DC link. The aim of this research is to model control of direct driven 1.5 MW wind turbine permanent magnetic synchronous generator (PMSG) which feeds alternating current (AC) power to the utility grid .The m...

Transformer protection is critical issue in power system as the issue lies in the accurate and rapid discrimination of magnetizing inrush current from internal fault current. Artificial neural network has been proposed and has demonstrated the capability of solving the transformer monitoring and fault detection problem using an inexpensive, reliable, and noninvasive procedure. This paper gives ...