Optimal AGC regulator for multi-area interconnected power systems with parallel AC/DC links

IET Renewable Power Gen

2021

A maiden attempt was made to demonstrate the impact of realistic high‐voltage direct current (RHVDC) tie‐line along with realistic dish‐Stirling solar thermal system (RDSTS) models in multi‐area load frequency control studies under a deregulated scenario. Area‐1, area‐2 and area‐3 comprise thermal‐RDSTS systems with relevant generation rate constraints. Each area includes two generation and two distribution companies. A new secondary controller with a cascaded combination of fractional order (FO) proportional derivative with filter coefficient (N) and FO‐proportional‐integral‐derivative with filter coefficient (N) (FOPDN‐FOPIDN) is proposed for the first time. The performance indices (peak magnitude, settling time and oscillations magnitude) of the proposed controller shows the dominance in comparison with the existing FOPI, PIDN and FOPIDN controllers in the policy schemes like poolco, bilateral and contract violation. A recent metaheuristic algorithm named the crow‐search algorithm is successfully applied for simultaneous optimisation of the proposed FOPDN‐FOPIDN controller gains and RDSTS parameters under the deregulated environment for the first time. Under the above policy schemes, the effect of RDSTS and RHVDC tie‐line using FOPDN‐FOPIDN controller is investigated, and the use of RHVDC tie‐line with AC tie‐line is explored. System dynamic response comparison with parallel AC‐RHVDC tie‐lines reveals better performance over AC tie‐line and RHVDC tie‐line when used alone.

Δ P_{tie, DC} = \frac{K_{DC}}{1 + s . T_{normalDC}}

where Δ P tie , DC is the power in the DClink. HVDC gain constant is K DC and is given by 1.0; T DC is settling time for a small load disturbance and is given by 0.2 s.…”

Section: A Brief Description Of the System Model Under The Deregulatementioning

confidence: 99%

Load frequency control of a multi‐area system incorporating realistic high‐voltage direct current and dish‐Stirling solar thermal system models under deregulated scenario

IET Renewable Power Gen

2021

“…By comparing (18) and (19), it can be stated that for a sudden change on the input signal R j (s) does not affect the derivative (K Dj , j ) and proportional (K Pj , j ) terms. This shows the superiority of FOPI-FODF over conventional FOPIDF controller.…”

Section: Fo Proportional Integral Minus Fo Derivate With Filter Contrmentioning

confidence: 99%

“…The benefit of combining DC links with AC links was discussed in [17]. The approximate transfer function model of the HVDC link was used in many AGC studies [17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Automatic generation control of a solar thermal and dish‐stirling solar thermal system integrated multi‐area system incorporating accurate HVDC link model using crow search algorithm optimised FOPI Minus FODF controller

IET Renewable Power Generation

2019

This article demonstrates the automatic generation control of a multi-area system incorporating various sources. Area-1 and area-2 consist of thermal and parabolic trough solar thermal plant (PTSTP) of fixed and random solar insolation, respectively, and area-3 comprises of thermal and realistic dish-stirling solar thermal system units. A maiden effort has been made to use a fractional order (FO) proportional-integral minus FO derivative with filter coefficient (FOPI-FODF) controller as a secondary controller. The controller gains are optimised using a novel algorithm called crow search algorithm. Comparisons of system dynamic response with and without renewable energy sources for FOPI-FODF, and for some commonly used integer order and FO controller's reveals the better performance of FOPI-FODF controller. A study comparing both fixed and random solar insolation in PTSTP of different areas have been tested. An accurate high-voltage direct current (AHVDC) line model is designed using inertia emulation strategy and is placed instead of AC tie line, and with parallel AC tie lines resulting in better system dynamic performances than AC tie line alone. The selection of the optimum location of AHVDC line in parallel AC tie line exposes the AHVDC line connected with the area where the system is disturbed.

“…Higher values of L result in complex approximations and ripples are eliminated. L should be chosen in advance and are given by (21) to (25).…”

Section: Fo Proportional-integral-fo Integral Derivative With Filtementioning

confidence: 99%

“…If this mismatch is hampered, it leads to deviations in tie‐power and frequency from actual values . Many research articles are available on AGC in the past . The early works on AGC started with single‐area thermal system and further extended to multiarea thermal systems.…”

Section: Introductionmentioning

confidence: 99%

AGC of a multiarea system incorporating accurate HVDC and precise wind turbine systems

Int Trans Electr Energ Syst

2019

This article highlights the dynamic model of an accurate high‐voltage direct current (AHVDC) using inertia emulation control strategy of a transmission line in automatic generation control (AGC) of a multiarea different source system. The three‐area system composes of thermal and precise wind turbine system using fixed and random wind velocities in areas 1 and 2. Area 3 composes of thermal and solar thermal power plants. Governor dead band and appropriate generation rate constraints are considered for thermal systems. A new fractional‐order cascaded controller named as fractional‐order proportional‐integral cascaded with fractional‐order integral derivative with filter (FOPI‐FOIDN) is used as a secondary controller. The controller gains and other parameters are optimized by using crow search algorithm in AGC studies for the first time. Comparison of system dynamics with various fractional‐order controllers and proposed FOPI‐FOIDN controller while considering one at a time reveals better dynamic performance of the latter. Comparison of dynamic response of the system with AC tie‐line, AHVDC tie‐line, and parallel combination of AC‐AHVDC tie‐lines while considering one at a time reveals better performance of the latter. The optimum location of AHVDC tie‐line in parallel AC tie‐line is found in the area where the system is disturbed.