Study On Operation Of Self-Synchronous Paralleling And Asynchronous Paralleling Of Powerformer

Powerformer is a new type of high-voltage generator. Profiting from using XLPE cable as its stator winding, Powerformer can generate very high voltage and can be connected to the power grid directly without step-up transformer.At present, there is no Powerformer running experience in China. Though several Powerformers have been running abroad and some running experience has been obtained, there is little theory study about Powerformer running and paralleling with power grid. In order to make sure Powerformer can be paralleled with power grid successfully and runs well, we need to do enough study about running and paralleling. When Powerformer is about to be get running in power-systems, many problems should be considered, including the way of paralleling and the fault while paralleling, et.This paper studies problems about self-synchronous paralleling of Powerformer. Electromagnetic process of self-synchronous paralleling is analyzed. With properly assumptions, mathematical expressions of armature current, rotor current and electromagnetic torque are deduced. And the expressions are used to calculate transient current and electromagnetic torque of self-synchronous paralleling of Powerformer.In the paper, superposition principle is used to analyze asynchronous paralleling of Powerformer. The complex process is split into two separated easier ones. Then expressions of current and electromagnet torque are deduced. The method is use to calculate transient current and electromagnetic torque of asynchronous paralleling of Powerformer.Finally, the paper provides a numerical method for the calculation of self- synchronous paralleling and asynchronous paralleling. Equation of state is used. At last, this paper mainly discussed current and torque of asynchronous as a function of phase difference between Powerformer and power grid.