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G. Narayanan - One of the best experts on this subject based on the ideXlab platform.

  • a simple Analog Controller for single phase half bridge rectifier
    IEEE Transactions on Power Electronics, 2007
    Co-Authors: R. Ghosh, G. Narayanan
    Abstract:

    A simple Analog Controller is proposed for the single-phase half-bridge pulsewidth modulation rectifier to maintain near unity power factor at the input and balance the voltages across each half of the dc bus. The Controller works in the principle of constant-frequency current programmed control. The required gating pulses are generated by comparing the input current with a linear and bipolar carrier without sensing the input voltage. Two voltage Controllers and a single reset-integrator are used to generate the carrier. All the necessary control operations are performed without using any phase locked loop, multiplier, and/or divider circuits. Resistor based sensors are used to measure the voltages across two halves of the dc bus and the input current. The Controller can be fabricated as a single integrated circuit. The averaged small signal models and all the necessary design equations are provided. The condition of stability against subharmonic oscillation is analyzed. Calculation of switching and conduction losses is presented. The control concept is validated through simulation and also experimentally on an 800-W half-bridge rectifier. Experimental results are presented for ac-dc application, and also for ac-dc-ac application with both linear and nonlinear loads at two different output fundamental frequencies (50 and 60Hz)

  • A Simple Analog Controller for Single-Phase Half-Bridge Rectifier and its Application to Transformerless UPS
    2005 IEEE 36th Power Electronics Specialists Conference, 2005
    Co-Authors: R. Ghosh, G. Narayanan
    Abstract:

    A simple, low-cost, constant frequency, Analog Controller is proposed for the front-end half-bridge rectifier of a single-phase transformerless UPS system to maintain near unity power factor at the input and zero dc-offset voltage at the output. The Controller generates the required gating pulses by comparing the input current with a periodic, bipolar, linear carrier without sensing the input voltage. Two voltage Controllers and a single integrator with reset are used to generate the required carrier. All the necessary control operations can be performed without using any PLL, multiplier and/or divider. The Controller can be fabricated as a single integrated circuit. The control concept is validated through simulation and also experimentally on an 800 W half-bridge rectifier. Experimental results are presented for ac-dc application, and also for ac-dc-ac UPS application with both sinusoidal and nonlinear loads. The simulation and experimental results agree well

R. Ghosh - One of the best experts on this subject based on the ideXlab platform.

  • a simple Analog Controller for single phase half bridge rectifier
    IEEE Transactions on Power Electronics, 2007
    Co-Authors: R. Ghosh, G. Narayanan
    Abstract:

    A simple Analog Controller is proposed for the single-phase half-bridge pulsewidth modulation rectifier to maintain near unity power factor at the input and balance the voltages across each half of the dc bus. The Controller works in the principle of constant-frequency current programmed control. The required gating pulses are generated by comparing the input current with a linear and bipolar carrier without sensing the input voltage. Two voltage Controllers and a single reset-integrator are used to generate the carrier. All the necessary control operations are performed without using any phase locked loop, multiplier, and/or divider circuits. Resistor based sensors are used to measure the voltages across two halves of the dc bus and the input current. The Controller can be fabricated as a single integrated circuit. The averaged small signal models and all the necessary design equations are provided. The condition of stability against subharmonic oscillation is analyzed. Calculation of switching and conduction losses is presented. The control concept is validated through simulation and also experimentally on an 800-W half-bridge rectifier. Experimental results are presented for ac-dc application, and also for ac-dc-ac application with both linear and nonlinear loads at two different output fundamental frequencies (50 and 60Hz)

  • A Simple Analog Controller for Single-Phase Half-Bridge Rectifier and its Application to Transformerless UPS
    2005 IEEE 36th Power Electronics Specialists Conference, 2005
    Co-Authors: R. Ghosh, G. Narayanan
    Abstract:

    A simple, low-cost, constant frequency, Analog Controller is proposed for the front-end half-bridge rectifier of a single-phase transformerless UPS system to maintain near unity power factor at the input and zero dc-offset voltage at the output. The Controller generates the required gating pulses by comparing the input current with a periodic, bipolar, linear carrier without sensing the input voltage. Two voltage Controllers and a single integrator with reset are used to generate the required carrier. All the necessary control operations can be performed without using any PLL, multiplier and/or divider. The Controller can be fabricated as a single integrated circuit. The control concept is validated through simulation and also experimentally on an 800 W half-bridge rectifier. Experimental results are presented for ac-dc application, and also for ac-dc-ac UPS application with both sinusoidal and nonlinear loads. The simulation and experimental results agree well

Paolo Mattavelli - One of the best experts on this subject based on the ideXlab platform.

  • Digital gain-scheduled control of a high frequency parallel resonant DC-DC converter
    2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC), 2012
    Co-Authors: Marko Vulovic, Dushan Boroyevich, Paolo Mattavelli
    Abstract:

    The nonresonant-coupled parallel resonant converter is discussed and a reference classical Analog Controller is designed and simulated. Based on the strong relationship observed between low-frequency converter gain and operating point, a band-limited gain-scheduled digital Controller is proposed, designed, and simulated, showing 5:1 improved worst-case control bandwidth as compared with the Analog Controller. A prototype is designed and built which experimentally validates the simulation results with good correlation. The effect of digital modulator resolution is discussed.

  • A Simple Digital Autotuning For Analog Controller in SMPS
    IEEE Transactions on Power Electronics, 2010
    Co-Authors: Stefano Saggini, Alessandro Costabeber, Paolo Mattavelli
    Abstract:

    This paper discusses the self-tuning capabilities of an Analog current-mode Controller for switch-mode power supplies. The proposed tuning techniques are based on the insertion of nonlinear (NL) blocks in the Analog control loop and the generation of a controlled oscillation on the output voltage, in order to measure the closed-loop properties like gain margin, phase margin, and crossover frequency and to tune the Analog Controller according to the desired specifications. The NL blocks are based either on the NL gain or NL phase. The most relevant properties are as follows: 1) the oscillation amplitude is controlled by the NL action during the tuning procedure; 2) A/D converters are not required; 3) the parameter variations can be obtained with ancillary Analog blocks (variable gain operational transconductance amplifier, switched capacitors, etc.); and 4) the tuning digital control algorithm is simple. Experimental results on a 10 A, 1.5 V point-of-load converter, where the Controller tuning has been implemented using components off-the-shelf and a field-programmable gate array are provided to show the properties of the proposed system.

  • A Simple Digital Auto-Tuning For Analog Controller in SMPS
    2009 Twenty-Fourth Annual IEEE Applied Power Electronics Conference and Exposition, 2009
    Co-Authors: Stefano Saggini, Alessandro Costabeber, Paolo Mattavelli
    Abstract:

    This paper discusses the self-tuning capabilities of an Analog current-mode Controller for switch-mode DC-DC converters. The proposed tuning techniques are based on the insertion of non-linear blocks in the Analog control loop and the generation of a controlled oscillation on the output voltage in order to measure the closed-loop properties like gain margin, phase margin and crossover frequency and to tune the Analog Controller according to the desired specifications. The non-linear blocks are based either on the non-linear gain or non-linear phase. The most relevant properties are: 1) the oscillation amplitude is controlled by the non-linear action during the tuning procedure; 2) A/D converters are not required; 3) the parameter variations can be obtained with ancillary Analog blocks (variable gain Operational Transconductance Amplifier (OTA), switched capacitors, etc.); 4) the tuning digital control algorithm is simple. Experimental results on a 10 A, 1.5 V point-of-load converter, where the Controller tuning has been implemented using Components Off-The-Shelf (COTS) and a Field Programmable Gate Array (FPGA) for the digital tuning algorithm, are provided to show the properties of the proposed system.

K M Smedley - One of the best experts on this subject based on the ideXlab platform.

  • a new Analog Controller for three phase four wire voltage generation inverters
    IEEE Transactions on Power Electronics, 2009
    Co-Authors: K M Smedley
    Abstract:

    This paper introduces a new Controller for three-phase four-wire inverters, with the control goal of generating high-quality three-phase output voltages for all sorts of linear/nonlinear and balanced/unbalanced loads. The proposed Controller employs a circuit-level decoupling method, and it is implemented by logic circuitry in combination with a control core and a feedback signal processor. Almost all dc-dc control methods can be adapted as the control core, while the feedback signal processor can be implemented by either voltage compensator and/or current compensator. The implementation of the Controller is simple and flexible with only logic and Analog circuitry needed. Yet, it demonstrated experimentally excellent load handling and source voltage noise rejection ability. The prototype is tested under balanced and unbalanced resistive and nonlinear loads, as well as under extreme load transients. It is also tested with power from a noisy dc input source. In all cases, the prototype demonstrated high-quality output voltages.

  • a new Analog Controller for three phase voltage generation inverter
    IEEE Transactions on Industrial Electronics, 2008
    Co-Authors: Taotao Jin, K M Smedley
    Abstract:

    This paper introduces a new Controller for a threephase inverter, with a control goal of generating desired threephase output voltages. The proposed Controller employs a circuit-level decoupling method, and it is implemented by logic circuitry in combination with a control core and a feedback signal processor. Almost all DC-DC Controllers can be adapted as the control core, whereas the feedback signal processor can be implemented by either voltage compensator and/or current compensator. The Controller's implementation is simple and flexible with logic and Analog circuitry. Yet, it demonstrates experimentally excellent load handling, source voltage noise rejection, and reference tracking ability. The prototype is tested under resistive load, highly nonlinear load, and extreme load transients; aside from that, it is also tested under noisy source voltage and sudden reference change. In all cases, the prototype demonstrated high-quality output voltages.

  • a new Analog Controller for three phase four wire voltage generation inverters
    Applied Power Electronics Conference, 2008
    Co-Authors: K M Smedley
    Abstract:

    This paper introduces a new Controller for three-phase four-wire inverters, with the control goal of generating high quality three-phase output voltages for all sorts of linear/nonlinear and balanced/unbalanced loads. The proposed Controller employs a circuit-level decoupling method and it is implemented by logic circuitry in combination with a control core and a feedback signal processor. Most DC-DC control methods can be adapted as the control core, while the feedback signal processor can be implemented by either voltage compensator and/or current compensator. The implementation of the Controller is simple and flexible with only logic and Analog circuitry needed. Yet, it demonstrated experimentally excellent load handling and source voltage noise rejection ability. The prototype is tested under balanced and unbalanced resistive and non-linear loads, as well as under extreme load transients. Besides, it is also tested with power from noisy DC input source. In all cases, the prototype demonstrated high quality output voltages.

Hanchung Lee - One of the best experts on this subject based on the ideXlab platform.

  • Analog Controller ic design for single stage photovoltaic inverters
    Fuzzy Systems and Knowledge Discovery, 2011
    Co-Authors: Yeongchau Kuo, Lijen Liu, Hanchung Lee
    Abstract:

    In this paper, the Analog Controller integrated circuit (IC) design is implemented for single-stage photovoltaic (PV) inverters. This research employed IC design technology to implement the Controller for the proposed PV inverter. And then, the IC and system models are integrated into a PV energy conversion system in order to verify the total system performance. The key circuits of Analog Controller IC are operational amplifier, voltage-controlled oscillator, and hysteresis comparator. The Controller IC has been fabricated with TSMC 0.35um 2P4M mixed-signal CMOS process through the support of Chip Implementation Center. Computer simulations and experimental results demonstrate the accuracy and the superior performance of the proposed technique.

  • FSKD - Analog Controller ic design for single-stage photovoltaic inverters
    2011 Eighth International Conference on Fuzzy Systems and Knowledge Discovery (FSKD), 2011
    Co-Authors: Yeongchau Kuo, Lijen Liu, Hanchung Lee
    Abstract:

    In this paper, the Analog Controller integrated circuit (IC) design is implemented for single-stage photovoltaic (PV) inverters. This research employed IC design technology to implement the Controller for the proposed PV inverter. And then, the IC and system models are integrated into a PV energy conversion system in order to verify the total system performance. The key circuits of Analog Controller IC are operational amplifier, voltage-controlled oscillator, and hysteresis comparator. The Controller IC has been fabricated with TSMC 0.35um 2P4M mixed-signal CMOS process through the support of Chip Implementation Center. Computer simulations and experimental results demonstrate the accuracy and the superior performance of the proposed technique.