Analysis and investigation on direct and cross coupling effect of small isolated and interconnected wind diesel power generating system

Abstract

This study presents the analysed result of wind-diesel system with the consideration of real power-frequency control, reactive power-voltage control as well as cross-coupling between reactive power-frequency and real power-voltage control. The system under study uses synchronous generator (SG) for diesel generator and induction generator (IG) for wind generation systems. The mathematical model of the system with both direct and cross-coupling effect is derived to simulate the behaviour of the wind-diesel system. The classical control technique and eigenvalue, participation factor matrix is used to study the strength of the direct and cross-coupling effect, in the studied system. The simulated responses of the system under various types of disturbances are presented to show the cross-coupling effect in the wind-diesel system. System performances under interconnected mode of operation is also studied. Nomenclature V, f system voltage and frequency, respectively δ angle between armature internal voltage and system voltage V av , V fd , E fd amplifier, exciter feedback, exciter voltage, respectively K E , K A , K F exciter, amplifier, stabiliser gain, respectively E q , E q ′ internal armature voltage at steady state and transient, respectively P l , Q l real and reactive load, respectively P ig , P sg real power output of IG and SG, respectively Q ig , Q sg reactive power output of IG and SG, respectively P iw output power of wind turbine P wt wind power r e , x e , s l equivalent resistance, reactance and slip of IG Δ small perturbation in the variable

Stability Improvement of Isolated Wind-Diesel System with Optimized STATCOM Controller

“…When optimized with the ITSE criteria the transients settle in 5 cycles. The optimal STATCOM controller designed here accurately settles the ∆V following disturbance to nearly zero compared to a case where no reactive power support is given [4]. Thus a faster control is achieved.…”

“…With the added demand for reactive power by IG, the generation faces mismatch. Thus, generator terminal voltage is more prone to fluctuation in such case and has detrimental effect on the supply quality and stability [4]. Hence, it is an important problem to be mitigated.…”

Coordinated regulation of voltage and load frequency in demand response supported biorenewable cogeneration‐based isolated hybrid microgrid with quasi‐oppositional selfish herd optimisation

“…The detailed linearised model of AVR with Controller2 is illustrated in Figure 1C. The system voltage is expected to be regulated by the inclusion of an IEEE type‐I excitation‐based AVR 31,32 to the proposed hμG coupled with ALFC, and the detailed design/modelling of this AVR is discussed in Anderson and Fouad, Tah and Das, Hussain et al 21,31‐32 The deviation in equivalent power ( ΔP EQ ) due to AVR action, and change in the terminal voltage ( Δu ) could be expressed as Equation (2). 21,34 The field responses ( ΔE f ), exciter responses ( ΔE e ), and error voltage ( ΔE u ) are expressed in Equations (3) to (5), respectively.…”

“…The DRC unit is supposed to include the charging stations of HEV of the locality, to support hμG during frequent load variations 30 . The coordinated regulation of voltage and load frequency in the proposed hμG are designed with IEEE type‐I excitation‐based AVR 31,32 and ALFC 30 respectively. The controller1 is deployed for ALFC 33 to coordinate BEGS output, and controller2 is solely deployed for AVR 34 of the proposed hμG, as viewed in Figure 1B.…”

The stability control for isolated wind‐diesel power system based on the cross coupling effect model

“…In a large-scale power system, the interaction of active power fluctuation for the voltage and reactive power fluctuation for the frequency is small because the line resistance can be ignored, so the active power and reactive power can be decoupled for the model construction. But it cannot be completely decoupled in the small-scale power system because of the line resistance influence, so the cross-coupling needs to be considered for improving the model construction accuracy as described in [20]. However, this can make the system model more complex for voltage and frequency control.…”