Poor control of the nuclear steam generator (SG) water level of pressurized Water Reactor can lead to frequent reactor shutdowns. In addition, the steam generator is a highly complex, nonlinear and time-varying system and its parameters vary with operating conditions. The dynamics of a nuclear steam generator is very different according to the power levels and changes as time goes on. Therefore...

The objective of this paper is to assess 10 MW directdrive permanent-magnet (DDPM) generator systems with different control strategies namely pitch control and active speed stall control. In the active speed stall control concept, there is no pitch mechanism, and the rotor speed is actively controlled by the generator to control the output power. The active speed stall control wind turbine with...

An accurate average value model of synchronous machine-rectifier system considering the effect of stator resistance is derived in this paper. A proper voltage-behind-reactance synchronous machine model without any approximations is used for the generator that allows effective calculation of commutation displacement angle. All rectification modes of the rectifier are studied. A detailed switchin...

The vast majority of wind turbines that are currently being installed use one of the three main types of electromechanical conversion system. The first type is known as the Danish concept. The second type uses a doubly fed induction generator instead of a squirrel cage induction generator. The third type is called the ‘direct-drive wind turbine’ because it does not need a gearbox. In this paper...

The objective of the work at Chalmers test station is to carry out research, maintain and run the wind turbine at the plant. The station is used for research projects and as a demonstration and lab facility. The turbine is equipped with a permanent magnet direct-driven generator and an electrical system with a DC link suited for variable speed operation. Research focuses mainly on the generator...

This paper proposes an optimal transmission expansion planning (TEP) which is based on determining share of each line in merchandizing surplus (MS) of system, determining by Independent System Operator (ISO). The more share of a line in MS of system denotes the priority of a line for expansion. The procedure of determining MS of each line in a power system is based on determining the MS share o...

In this paper a new algorithm based on phasor measurements for estimating the Thévenin Equivalent (TE) and system inertia constant is proposed. The method estimates the network TE seen from a generator terminal and equivalent system inertia constant by means of phasor data that is available at Phasor Data Concentrator (PDC) center. It is shown that the parameters of the TE could be estimated at...

A detailed model of wind power station, including Double Fed Induction Generator, DFIG is presented in this paper. Two control mechanisms are included in the model. The inner control system uses stator flux oriented control for the rotor side converter and grid voltage vector control for the grid side converter. The outer control system is used for wind turbine pitch angle. PSCAD/EMTDC is us...

This paper presents actual cases of steady reactive power oscillation of Distributed Generations (DGs) during parallel operation with the main grid. The cause of the problem was found to be the adverse effects of excitation system voltage regulation. It is shown, through preliminary investigation and detailed simulation studies, that how the excitation control system can be modified to overcome...