Analysis And Computation On Limit Of Leading Phase Operation Of Powerformer

Powerformer is a new type of high-voltage generator. The stator winding of it is XLPE (cross-linked polyethylene) with high Voltage. This innovational structure makes it be able to generate high voltage of the grid and connect to the power line directly, it offers the power plant several advantages such as enhanced reliability, higher efficiency etc. So, it is necessary to study the operation of Powerformer systematically. The stability and depth of the leading phase operation of Powerformer is studied thoroughly in this paper.The developing background and study state at home and broad are introduced in this paper firstly, and the research significance of stability and depth of the leading phase operation of Powerformer is analyzed.Then, the stability and depth of the leading phase operation of Powerformer is analyzed, and the mathematical model of static and dynamic operation state for Powerformer is proposed, the expressions of static stable power characteristic and static stable limit for Powerformer are deduced. The influence of external reactance and field regulation on the static power characteristic of Powerformer is analyzed, it is proved that the decreased the static stability of leading phase operation of Powerformer with the contrast research method. The dynamic stability of leading phase operation of Powerformer is also analyzed in this paper, the physical processes of Powerformer system are analyzed respectively when the line has breakdown, the circuit diagram is plotted when Powerformer runs in normal state and fault state, the expression of power is deduced basing on the equivalent circuit when Powerformer runs in fault, the effect of fault state on leading phase operation of Powerformer is analyzed. the transient stability limit is obtained.At the same time, the physical process of reactive power regulation is analyzed systematically basing on the parameters of the Powerformer model, the expression of V curves is deduced, V curves is given by simulation, the change curves of parameter along with reactive power of leading phase operation of Powerformer are given.Finally, a simulation model of Powerformer is proposed in SIMULINK/SPS. The operation of Powerformer from steady-state to leading-phase state is simulated in a single-machine infinite-bus system. The simulations of stator voltage and current, power-angle and power factor under leading phase operation of Powerformer are obtained, the influence of field regulation on the leading phase operation of Powerformer is also analyzed, the effect on leading phase operation of Powerformer is analyzed.The conclusion of this paper provides some basis for the reliable design and operation of Powerformer, having certain theoretical significance and practical value.