Load Identification of DC-DC Buck Converter
01 Jan 2012-
TL;DR: In this article, the authors developed Signal Processing methods which increase the performance, functionality and reliability of dc-dc converters which is part of an ongoing project of Ericsson together with Blekinge Institute of Technology.
Abstract: The thesis is to develop Signal Processing methods which increase the performance, functionality and reliability of dc-dc converters which is part of an ongoing project of Ericsson together with Blekinge Institute of Technology. The aim of this project is to model the buck converter system of Ericson’s BMR450 using MATLAB Simulink and develop methods to identify the capacitive load. Our first approach is to derive the equation which gives relation of capacitive load with output voltage in time domain analysis. Our second method deals with resonant point of frequency response of buck converter using Linearization method. Our final method deals in frequency domain analysis using FFT. For different values, we calculated the capacitive load values using proposed methods and compared them to the original values to observe the percentage of errors.
References
More filters
Book•
01 Jan 1994
TL;DR: I. Models for Systems and Signals, physical Modelling, simulation and model applications.
Abstract: I. MODELS. 1. Systems and Models. 2. Examples of Models. 3. Models for Systems and Signals. II. PHYSICAL MODELLING. 4. Basic Principles for Physical Modelling. 5. Some Basic Physical Analogies. 6. Bond-graphs. 7. Computer Support for Physical Modelling. III. SYSTEM IDENTIFICATION. 8. Estimation of Transient Response, Spectra and Frequency Functions. 9. Parameter Estimation of Dynamical Models. 10. System Identification as Tool for Modeling. IV. SIMULATION AND MODEL APPLICATIONS. 11. Simulation. 12. Simulators. 13. Model Validation and Model Use. Appendix A: Linear Systems - Description and Properties. Appendix B: Linearization. Appendix C: Signal Spectra.
558 citations
24 May 2004
TL;DR: In this article, the authors discuss the impact of digital control in high-frequency switched-mode power supplies (SMPS), including point-of-load and isolated DC-DC converters, microprocessor power supplies, power factor correction rectifiers, electronic ballasts, etc., where high efficiency, static and dynamic regulation, low size and weight, as well as low controller complexity and cost are very important.
Abstract: In this paper, we discuss the impact of digital control in high-frequency switched-mode power supplies (SMPS), including point-of-load and isolated DC-DC converters, microprocessor power supplies, power-factor-correction rectifiers, electronic ballasts, etc., where switching frequencies are typically in the hundreds of kHz to MHz range, and where high efficiency, static and dynamic regulation, low size and weight, as well as low controller complexity and cost are very important. To meet these application requirements, a digital SMPS controller may include fast, small analog-to-digital converters, hardware-accelerated programmable compensators, programmable digital modulators with very fine time resolution, and a standard microcontroller core to perform programming, monitoring and other system interface tasks. Based on recent advances in circuit and control techniques, together with rapid advances in digital VLSI technology, we conclude that high-performance digital controller solutions are both feasible and practical, leading to much enhanced system integration and performance gains. Examples of experimentally demonstrated results are presented, together with pointers to areas of current and future research and development.
474 citations
"Load Identification of DC-DC Buck C..." refers background in this paper
...The steady state switch voltage is a periodic pulsating waveform has the amplitude approximately equal to the input voltage amplitude [2]....
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...Page 12 several buck or similar converter modules which operate in parallel to share the load current in order to improve dynamic response [2]....
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...The buck converter consists of main power switch, a diode, a low-pass filter (L and C) and a load [2]....
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TL;DR: This paper presents a modified correlation method for system identification of power converters with digital control by injecting a multiperiod pseudo random binary signal to the control input of a power converter, derived by cross-correlation of the input signal and the sensed output signal.
Abstract: For digitally controlled switching power converters, on-line system identification can be used to assess the system dynamic responses and stability margins. This paper presents a modified correlation method for system identification of power converters with digital control. By injecting a multiperiod pseudo random binary signal (PRBS) to the control input of a power converter, the system frequency response can be derived by cross-correlation of the input signal and the sensed output signal. Compared to the conventional cross-correlation method, averaging the cross-correlation over multiple periods of the injected PRBS can significantly improve the identification results in the presence of PRBS-induced artifacts, switching and quantization noises. An experimental digitally controlled forward converter with an FPGA-based controller is used to demonstrate accurate and effective identification of the converter control-to-output response.
248 citations
"Load Identification of DC-DC Buck C..." refers methods in this paper
...In [8], the system frequency response is obtained by using nonparametric method by means of correlation analysis....
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TL;DR: The proposed system identification technique is computationally efficient, based on a dichotomous coordinate descent algorithm, and uses an infinite impulse response adaptive filter as the plant model, and reduces the computational complexity of existing recursive least squares algorithms.
Abstract: This paper introduces a novel technique for online system identification. Specific attention is given to the parameter estimation of dc-dc switched-mode power converters; however, the proposed method can be applied to many alternative applications where efficient and accurate parameter estimation is required. The proposed technique is computationally efficient, based on a dichotomous coordinate descent algorithm, and uses an infinite impulse response adaptive filter as the plant model. The system identification technique reduces the computational complexity of existing recursive least squares algorithms. Importantly, the proposed method is also able to identify the parameters quickly and accurately, thus offering an efficient hardware solution that is well suited to real-time applications. Simulation analysis and validation based on experimental data obtained from a prototype synchronous dc-dc buck converter is presented. Results clearly demonstrate that the estimated parameters of the dc-dc converter are a very close match to those of the experimental system. The approach can be directly embedded into adaptive and self-tuning digital controllers to improve the control performance of a wide range of industrial and commercial applications.
81 citations
"Load Identification of DC-DC Buck C..." refers methods in this paper
...Where as in parametric estimation, a model structure is proposed and the parameter of the model is identified using information extracted from the system [4]....
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17 Jun 2007
TL;DR: In this paper, a discrete time-domain based system identification method for PWM DC-DC converters is presented, which is capable of successfully reconstructing the system's model from an arbitrary excitation at the command input.
Abstract: A discrete time-domain based system identification method for PWM DC-DC converters is presented. The proposed procedure is capable of successfully reconstructing the system's model from an arbitrary excitation at the command input. In this study, a step perturbation was applied, which is simple to apply and has an intuitive interpretation of the output response. The effects of switching and quantization noise were overcome by choosing the sampling instance to be after the switching oscillations decay significantly and by averaging the responses of synchronously perturbed sequences. The proposed method was evaluated on Buck and Boost converters. The digital data acquisition procedure was implemented on a TMS320F2407 DSP core. Excellent agreement was found between simulations and experimental results.
28 citations
"Load Identification of DC-DC Buck C..." refers methods in this paper
...So, better control can be obtained by using experimental data to determine the load information [3]....
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