Optimal current calculation for a PMSG based wind energy system integrated into an unbalanced weak grid

Abstract

Grid connection is an important consideration when it comes to integrating an energy source. A common problem with the existing wind energy conversion systems is that they are often located far from energy consumption centres. Owing to their remote location these systems are sometimes forced to connect with weak distribution networks which are usually designed for small linear loads. When the nature of these loads is changed, the voltage level at the point of common coupling may go above or below the nominal value which may result in power system instability. To improve the voltage variation, this study discusses an optimal current calculation technique based on Thevenin equivalent parameters of an electrical network. The functional capability of the technique is demonstrated with the help of a traditional converter topology utilised as a power conditioning system for a permanent magnet synchronous generator connected to a weak grid. The system in particular monitors a medium voltage distribution line, measures line load impedance and redistributes the currents in a way that provides maximised power transfer into a network with least incurred losses. A real-time controller with built-in data acquisition/fieldprogrammable gate array modules is used for the execution of experimental investigations.

Improved active power dynamic response of voltage‐controlled doubly fed induction generator

“…With the increase of single-unit capacity in wind farms, the voltage and frequency support capacity of the grid is becoming more and more insufficient. The wind farm encounters more serious challenges under the weak grid [5][6][7]. In the conventional control strategy of the wind power converter, the current control mode based on phase-locked loop (PLL) synchronisation is adopted, which externally shows the characteristics of a low-inertia current source [8,9].…”

Classical control algorithms for permanent magnet synchronous generator driven by diesel engine for power quality

“…This has been analyzed by THD analysis. There are few more application of control algorithm for effective utilization of PMSG is found in Khan et al 22 and Huynh et al 23 The optimal current control strategy has been discussed to control the output of PMSG which is working with weak and unbalance grid conditions 22 . The PMSG generator with rectifier is utilized for low speed applications in Huynh et al 23 …”

“…There are few more application of control algorithm for effective utilization of PMSG is found in Khan et al 22 and Huynh et al 23 The optimal current control strategy has been discussed to control the output of PMSG which is working with weak and unbalance grid conditions. 22 The PMSG generator with rectifier is utilized for low speed applications in Huynh et al 23 In this paper, a DG set with DE-driven PMSG and BESS-connected DSTATCOM at DC bus has been used for power quality improvement such as load balancing, harmonics mitigation, and reactive power compensation using different control algorithms. The main objective of BESS at DC link of VSC is to function as the load during light-load condition and function as the source during overload condition.…”