Design of robust self‐tuning regulator adaptive controller on single‐phase full‐bridge inverter

IET Control Theory & Appl

Jouybari

et al. 2022

Self Cite

The design of an on-line generalised predictive control (GPC) technique with a novel identification method is presented in this paper for a single-phase full-bridge inverter in the presence of different disturbances. The controller uses system discrete-time model to reach the control variables with a prediction over these values, followed by computing a cost function for control aims. However, in this controller, the need for the mathematical model of the system is removed since the black-box identification strategy is used. Moreover, GPC structure has many advantages including low computational complexity, systematic design procedure, and fixed switching frequency that makes it a good alternative for practical applications. Various disturbances can have a negative impact on a DC-AC inverter; thus, considering robust dynamics and ease of implantation, the GPC scheme is used along with an improved exponential regressive least square identification algorithm as an adaptive strategy in the controller. Moreover, the prediction horizons of this controller have been increased, resulting in its low steady-state error and better performance. Furthermore, harmonics in the sinusoidal signal can decrease the total efficiency of the system; thus, an LC filter is used to reduce the level of total harmonic distortion. However, the stability of the filter is the most challenging issue in designing a suitable controller. Finally, the strength of the current controller is verified using experimental and simulations results. INTRODUCTIONNowadays, power inverters are utilised in connecting renewable energy sources for power generation. Single-phase inverters are well-known and used in various industrial applications. A DC-AC H-bridge voltage source inverter (VSI) topology is selected here to feed different linear loads [1,2]. The generated sinusoidal waveform of an inverter must have a constant amplitude and frequency with a minimal rate of THD. To limit the THD level, various filters are suggested including LLCL, L, LC, and LCL. In fact, characteristics of the LC-type filter, make it can be the most suitable one for stand-alone structures (load connected) [3][4][5][6]. Stability proof of the filter is the primary concern which can harm system dynamics; thus, two strategies were presented for this challenge: passive and active damping schemes.In passive damping strategy, the inductor is modelled with a series resistor, while total system efficiency can be affected. However, for the second scheme, a closed-loop control strategies have been introduced [7]. However, the following This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Section: Rls Identification Processmentioning

confidence: 99%

Generalised predictive controller (GPC) design on single‐phase full‐bridge inverter with a novel identification method

Memeghani

IET Control Theory & Appl

Jouybari

et al. 2022

Self Cite

“…However, providing this strategy over the estimator can prevent an exponential increase of the covariance matrix when the regressive matrix is fixed. This novel improved strategy is introduced by (24).…”

Section: Improved Erls Identification Algorithmmentioning

confidence: 99%

A novel adaptive cascade controller design on a buck–boost DC–DC converter with a fractional‐order PID voltage controller and a self‐tuning regulator adaptive current controller

Mollaee

Saadat

et al. 2021

IET Power Electronics

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The design of a cascade controller is demonstrated for a buck-boost converter that is combined with two control loops consisting of inner and outer controllers. The outer loop is implemented by a fractional-order proportional-integrated-derivative (FO-PID) controller that works as a voltage controller and generates a reference current for the inner control loop. To provide faster dynamic performance for inner loop, a self-tuning regulator adaptive controller, which tries to regulates the current with the help of a novel improved exponential regressive least square identification in an online technique, is designed. Moreover, in the outer loop, to tune the gains of the FO-PID controller, a novel algorithm of antlion optimizer algorithm is used that offers many benefits in comparison with other algorithms. The system provided by the boost mode is a non-minimum phase system, which creates challenges for designing a stable controller. In addition, a single loop controller is proposed based on a PID controller tuned by a particle swarm optimization algorithm to be compared with the cascade controller. Cascade loop can present significant benefits to the controller such as better disturbance rejection. Finally, the strength of the presented cascade control scheme is verified in different performing situations by real-time experiments.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

“…All the issues mentioned by these strategies are covered by refs. [38,39], which proposed a novel robust identification method with a simple structure. Nonetheless, the main drawback concerned by this technique is its high dependency on parametric estimation.…”

Section: Introductionmentioning

confidence: 99%

Adaptive backstepping controller design on Buck converter with a novel improved identification method

Saadat

IET Control Theory & Appl

Mollaee

2022

Self Cite

An adaptive backstepping method is presented by this paper for a DC-DC Buck converter utilising a strategy for system identification with pulse width modulation in the presence of parametric uncertainties, load variations, and high variance noises. In this control structure, the system is assumed as a black-box block that can decrease the computational burden providing faster dynamics. An adaptive mechanism is adopted for the BSM using the Lyapunov definition, providing robust dynamics for the controller against various disturbances. In addition, a novel improved exponential recursive least-squares identification algorithm is proposed, which shows higher robustness in parametric estimations and can decrease the negative impact of disrupting factors on the estimator. Moreover, a particle swarm optimisation algorithm-based PID controller is designed to be compared with the proposed controller. Finally, the merits of the presented controller are validated for various working conditions through simulations and experiments. It can be seen that the adaptive backstepping method with the improved identification technique provides much better results with faster dynamics.