Adaptive Hysteresis Current Control Research Articles

Improving the Dynamic Response during Field Weakening Control of IPMSM Drive System using Adaptive Hysteresis Current Control Technique

Abstract This paper presents the control of IPMSM drive in flux weakening region, for high speed applications. An adaptive hysteresis band current controller has been designed and implemented in this work to overcome the drawbacks which are present in case of conventional hysteresis band current controllers such as: high torque ripple, more current error, large variation in switching frequency etc. The proposed current controller is a hysteresis controller in which the hysteresis band is programmed as a function of variation of motor speed and load current. Any variation in those parameters causes an appropriate change in the band which in turns reduces the torque ripple as well as current error of the machine. The proposed scheme is modeled and tested in the MATLAB-Simulink environment for the effectiveness of the study. Further, the result is validated experimentally by using TMS320F2812 digital signal processor.

Supervisory Nearly Constant Frequency Hysteresis Current Control for Active Power Filter Applications in Stationary Reference Frame

This paper proposes a new constant frequency space-vector hysteresis-band current control (CF-SVHCC) in the stationary reference frame (SRF) for three-level active power filter applications when applied to isolated neutral point (INP) systems. CF-SVHCC is designed based on two recognized modulation methods: 1) space-vector modulation and 2) adaptive hysteresis current control. The proposed technique consists of a simple circular hysteresis strategy around the current-error vector in SRF with the purpose of employing the zero- and nonzero-voltage vectors of the three-level voltage source inverter. CF-SVHCC continuously estimates an adaptive outer hysteresis-band in the SRF using the inverter switching signals by a simple and fast artificial neural network method called the adaptive linear neuron algorithm. The main part of CF-SVHCC is a supervisory control unit that operates in the SRF to avoid interphase dependency and systematically uses the voltage vectors associated with the estimated outer hysteresis-band to prevent a high switching frequency and, in turn, maintain the switching frequency constant. CF-SVHCC retains most benefits of the conventional HCC and also introduces additional advantages, including a constant switching frequency and the interphases independency in three-phase INP systems.

Current Control Technique for Three Phase Shunt Active Power Filter by Using Adaptive Hysteresis Current Controller

Current Control Technique for Three Phase Shunt Active Power Filter by Using Adaptive Hysteresis Current Controller

Power quality problem mitigation by unified power quality conditioner: an adaptive hysteresis control technique

An adaptive hysteresis current and voltage control technique for controlling Unified Power Quality Conditioner (UPQC) is proposed in this paper. The novelty of the proposed method is the series and shunt active power filters (APF) present in the UPQC has been controlled by the separate adaptive controllers for reducing the voltage and current perturbations. Here, the adaptive control technique utilises Artificial Neural Network (ANN) and Fuzzy Logic Controller (FLC) for generating the control pulses of the series and shunt APFs. In the adaptive control technique, ANN builds a target hysteresis control data based on the inputs such as voltage and current. By using the hysteresis control data, the control parameters are generated by the FLC. According to the output of FLC, PWM pulses are generated for controlling the APFs. The effectiveness of the proposed adaptive hysteresis control technique is identified by using the comparison analysis with the existing techniques.

A control scheme employing an adaptive hysteresis current controller and an uncomplicated reference current generator for a single-phase shunt active power filter

In recent years, active power filters (APFs) have become popular because of their excellent current harmonics and reactive power mitigation ability. The performance of the APF is directly related to the selected control strategy, which is mainly divided into 2, the reference current generation and current control. Most of the reference current generation methods are very complicated and require precise mathematical expressions. Moreover, being the most preferred current control method, conventional hysteresis controllers have a fixed bandwidth, which causes different total demand distortion values under different load conditions. In this study, a novel control scheme for a single-phase shunt APF is proposed. The proposed scheme uses an uncomplicated modification of the sine multiplication method for extraction of the reference filter current. Moreover, it employs an adaptive hysteresis current controller that changes its bandwidth according to the active power demand of the load. Thus, the requirements of the current harmonics limits specified in IEEE Std. 519-1992 are always fulfilled under different load conditions. A single-phase shunt APF controlled by the proposed scheme is modeled and simulated under nonlinear load conditions using MATLAB/Simulink. The simulation results indicate that the APF effectively compensate the current harmonics and reactive power at the point of common coupling of the AC mains.

Development and analysis of adaptive fuzzy controllers for photovoltaic system under varying atmospheric and partial shading condition

Control of power electronics converters used in PV system is very much essential for the efficient operation of the solar system. In this paper, a modified incremental conduction maximum power point tracking (MPPT) algorithm in conjunction with an adaptive fuzzy controller is proposed to control the DC–DC boost converter in the PV system under rapidly varying atmospheric and partial shading conditions. An adaptive hysteresis current controller is proposed to control the inverter. The proposed current controller provides constant switching frequency with less harmonic content compared with fixed hysteresis current control algorithm and sinusoidal PWM controller. The modeling and simulation of PV system along with the proposed controllers are done using MATLAB/SIMSCAPE software. Simulation results show that the proposed MPPT algorithm is faster in transient state and presents smoother signal with less fluctuations in steady state. The hardware implementation of proposed MPPT algorithm and inverter current control algorithms using Xilinx spartran-3 FPGA is also presented. The experimental results show satisfactory performance of the proposed approaches.

AN ADVANCED CURRENT CONTROLLER TECHNIQUE BASED ACTIVE POWER FILTER FOR POWER QUALITY IMPROVEMENT

Power Quality issues are becoming a major concern for today’s power system engineers. Large scale incorporation of non-linear loads has the potential to raise harmonic voltages and currents in an electrical distribution system to unacceptable high levels that can adversely affect the system. Active power filter (APF) based on power electronic technology is currently considered as the most competitive equipment for mitigation of harmonics and reactive power simultaneously. Instantaneous power theory is used for generation of reference current. This paper presents a comparative study of the performance of three current control strategies namely ramp comparison method, hysteresis current controller (HCC) and Adaptive hysteresis current controller(AHCC) and superiority of AHCC is established. Simulation results for all the method are presented using MATLAB/SIMULINK power system toolbox demonstrating the effectiveness of using adaptive hysteresis band.

A novel adaptive-fuzzy hysteresis current controller-based active power line conditioners for power quality enhancement

This paper presents a three-phase shunt active power line conditioner (APLC) for harmonics and reactive power compensation to enhance the power quality. The compensation process is based on sinusoidal extraction control method, which consists of positive-sequence voltage detector to regulate the distorted supply voltage and instantaneous real-power for fundamental component extraction from the distorted line current. The voltage source inverter (VSI)-based active filter switching pulses is generated through adaptive fuzzy hysteresis current controller (HCC). For the adaptive-fuzzy-HCC, bandwidth is calculated without precise knowledge of the APLC parameters (interface inductor and DC-link voltage), the hysteresis band value can be implemented with a fuzzy logic. A comparative assessment of fixed-HCC, adaptive-HCC and adaptive-fuzzy-HCC is carried out. The shunt APLC system is validated through extensive simulation under distorted supply voltage and non-linear load conditions.

Real-time implementation of adaptive fuzzy hysteresis-band current control technique for shunt active power filter

Optimising the performance of power system networks using conventional methods is quite difficult because of the complex nature of systems that are highly non-linear and non-stationary. In this study a hybrid adaptive fuzzy hysteresis current controller for shunt active power filter (SAPF) is proposed. The conventional adaptive hysteresis concept is hybridised with fuzzy logic controller (FLC), which facilitates discarding of uncertainty in the system. In fact, conventional proportional-integral (PI) controllers for shunt active filter are based on a linearised model that fails to react under transient events. On the other side, FLC has widened its applicability to many engineering fields and offers satisfactory results for a wide variety of operating conditions. It helps in fulfilling the need for perfection, such as stability and robustness for every system. All this motivated to adopt FLC for SAPF applications. By incorporating an adaptive fuzzy hysteresis band, active power filter (APF) gains outstanding compensation ability under steady-state and transient conditions. To validate the proposed approach, the system is implemented on a real-time digital simulator and adequate results are reported for its verification.

Double Band Adaptive Hysteresis Current Control Employed in Active Power Filter

Double Band Adaptive Hysteresis Current Control Employed in Active Power Filter

Fuzzy Adaptive Hysteresis Band Current Controller for Solar Photovoltaic Inverter

Photovoltaic inverters are important solar energy application. This paper presents a novel Fuzzy Adaptive Hysteresis Current Controller to control the inverter, used in the non-linear time-variant solar photovoltaic cell. The proposed controller has the advantages of both fuzzy as well as adaptive controller. It is capable of reducing the total harmonic distortion and to provide acceptable switching frequency. The mathematical model of Photovoltaic array is developed using the Newton’s method using the parameter obtained from a commercial photovoltaic data sheet under variable weather conditions, in which the effect of irradiance and temperature are considered. The modeled Photovoltaic array is interfaced with DC-DC boost converter, AC-DC inverter and load. A DC-DC boost converter is used to step up the input DC voltage of the Photovoltaic array while the DC-AC single-phase inverter converts the input DC comes from boost converter into AC. The performance of the proposed controller of inverter is evaluated through MATLAB-Simulation. Unlike standard adaptive controller designs, this adaptive fuzzy controller does not require an explicit mathematical model of the system. The results obtained with the proposed algorithm are compared with those obtained when using conventional fixed hysteresis current controller for single-phase photovoltaic inverter in terms of THD and switching frequency.

Review and Simulation of Fixed and Adaptive Hysteresis Current Control Considering Switching Losses and High-Frequency Harmonics

Hysteresis Current Control (HCC) is widely used due to its simplicity in implementation, fast and accurate response. However, the main issue is its variable switching frequency which leads to extraswitching losses and injecting high-frequency harmonics into the system current. To solve this problem, adaptive hysteresis current control (AHCC) has been introduced which produces hysteresis bandwidth which instantaneously results in smoother and constant switching frequency. In this paper the instantaneous power theory is used to extract the harmonic components of system current. Then fixed-band hysteresis current control is explained. Because of fixed-band variable frequency disadvantages, the adaptive hysteresis current control is explained that leads to fixing the switching frequency and reducing the high-frequency components in source current waveform. Due to these advantages of AHCC, the switching frequency and switching losses will be diminished appropriately. Some simulations are done in MATLAB/Simulink. The Fourier Transform and THD results of source and load currents and the instantaneous switching frequency diagram are discussed to prove the efficiency of this method. The Fourier Transform and THD results of source and load currents are discussed to prove the validity of this method.

Adaptive Hysteresis Current Control Of A Pwm Inverter At Constant Modulation Frequency Applied To Shunt Active Power Filters

This paper proposes a novel adaptive hysteresis current control strategy of a voltage-fed PWM inverter, where the switching frequency always remains constant and the harmonic ripple is minimum, irrespective of dc link voltage fluctuation and load parameter variation. The developed algorithm works well for single-phase as well as multi-phase inverters, although single-phase inverter operation, particularly in active harmonic filter mode, is emphasized in this paper. The algorithm uses fuzzy logic-based current error compensation, and it is simple to implement and does not involve any hysteresis-band calculation. The control strategy has been implemented digitally with a high-speed digital signal processor (TI-TMS320F2812). The proposed scheme has been thoroughly evaluated in laboratory by simulation as well as in experimental studies on a single-phase inverter, and its performance was found to be excellent.

A new adaptive hysteresis current control with unipolar PWM used in active power filters

This paper presents a new adaptive hysteresis current control with unipolar pulse width modulation based on magnitude and time errors. Variable switching frequency due to fixed hysteresis bands is known as a drawback of hysteresis current control used in power system applications, which generates sub-harmonics and low order harmonics, and affects the quality of the power systems. Adaptive hysteresis band is a classical method to control the switching frequency. Several issues and solutions have been discussed and proposed in this paper to keep the switching frequency constant. Simulations have been carried out to verify the proposed adaptive hysteresis band controller and the results are discussed in this paper.

A dead-beat adaptive hysteresis current control

A dead-beat adaptive hysteresis current control

Digital adaptive hysteresis current control with clocked commutations and wide operating range

A new hysteresis current control technique for voltage source inverters is proposed, which uses digital calculation to predict the proper band amplitude in order to minimize the error and give a switching frequency synchronized with a clock. The technique is self-adapting to supply and load parameters, and is easily extended to three-phase systems using the decoupling approach already proposed by the same authors. The proposed technique exhibits both the advantages typical of the hysteresis methods, and those of the digital controls. The implementation of the control is done by means of a standard microcontroller and simple additional circuitry. Simulations and experimental tests confirmed the advantages and the excellent performance of the new modulation method. >

Automated adaptive hysteresis current control technique for a voltage-fed PWM inverter

An adaptive hysteresis current control technique where the hysteresis band is automatically modulated by the input voltage integrator without the load information to maintain the modulation frequency nearly constant is presented. The computer simulation for the proposed current controller has been done and the results show good static and dynamic performances.