Mitja Truntič

FPGA implementation of digital controller for DC-DC buck converter

This paper describes a complete digital controlled dc-dc buck converter performed by FPGA circuitry. All tasks as are analog to digital conversion, control algorithm and pulse width modulation were implemented in the FPGA. This approach enables high-speed dynamic response and programmability of the controller without external passive components and more the controller structure could be changed from linear to non-linear easily also without external components. The applied algorithm enables the switching frequency of 100 kHz.

Voltage and Current-Mode Control for a Buck-Converter based on Measured Integral Values of Voltage and Current Implemented in FPGA

This paper describes a complete digitally controlled dc-dc buck converter performed by field-programmable gate array (FPGA) circuitry. The voltage and current-mode control is based on a voltage control oscillator (VCO) performed measurements regarding output-voltage and inductor current, respectively. This measurement principle also uses digital-counters (digital-integrators) in order to obtain integral values for the output-voltage and inductor current. In analog current-mode control, the instantaneous inductor current-value-measurement is used for the switching action. When the VCO is used for the inductor current measurement, the integral is measured during the switching-on time set as an observation interval and the switching action occurs based on this measurement. Such a principle enables full digitalization of the voltage- and current-control loop and also the used measurement principle is capable of rejecting the switching disturbances during current and voltage measurements. All the tasks for current and voltage control were implemented within the FPGA. The algorithm was verified by simulation and experimentation at a switching-frequency of 25kHz.

DCM-Based Zero-Voltage Switching Control of a Bidirectional DC–DC Converter With Variable Switching Frequency

This paper investigates a control approach for achieving reliable zero-voltage switching transitions within the entire operating range of a conventional nonisolated bidirectional dc-dc converter that utilizes synchronous rectification. The approach is based on operation in the discontinuous conduction mode with a constant reversed current of sufficient amplitude, which is achieved by load-dependent variation of the switching frequency. This paper focuses on the obtained resonant voltage transitions and provides analytical models for determining the reversed current and timing parameters that would ensure safe, reliable, and highly efficient operation of the converter. In addition, the proposed approach solves the synchronous transistors spurious turn-on and body diode reverse recovery induced issues, does not require any additional components or circuitry for its realization, and can be entirely implemented within a digital signal controller. The effectiveness and performance of the presented control approach was confirmed in a 1-kW experimental bidirectional dc-dc converter that achieved 97% efficiency over a wide range of output powers at switching frequencies above 100 kHz.

Digital current mode and voltage control for the dc-dc step-up converter based on the FPGA technology

This paper introduces a digitally performed voltage and current control mode for dc-dc step up converter based on FPGA technology. The voltage and current measurement was realized by using A/D converters as peripheral units of the FPGA system. Special attention was performed with current measurement and its A/D conversion due to the used predictive current mode algorithm which enables the fully digitalization of the whole control processes.

Voltage and current-mode control for a multiphase bi-directional DC-DC converter

This paper describes a completely digitally controlled bidirectional multi-phase dc-dc converter capable to operate in buck-and boost mode. All necessary tasks are performed within a FPGA circuitry. The voltage and current mode control is based on a voltage to frequency converter (u/f), also called voltage control oscillator (VCO), performing measurements of input/output-voltages and inductor-currents, respectively. This measurement principle uses digital counters (digital integrators) in order to obtain the average values of the output-voltages and inductor-currents. In analogue current-mode control the instantaneous current-value-measurement is used for the switching action. In case of using VCO measurement principle the digital equivalents of average values of input/output voltages and all measured currents will appear in the counter, which is the part of FPGA unit. All other tasks, like control algorithm and pulse width modulation, were also implemented within the FPGA. This approach enabled programmability and configurability of the control tasks. The proposed approach was verified experimentally.

Power management approach for hybrid multi-input/multi-output converter

Power management scheme for a converter system with multiple inputs and outputs is presented in the paper. The hybrid control approach was applied due to the required operation in various regimes. System collects the energy from multiple sources. The operation is supported by the battery.

Inter power electronic building blocks’ communication over two optical rings

Abstract Power electronic building blocks, initiated and sponsored by the Office of Naval Research, are based on the integration of power semiconductor elements with some degree of intelligence and data communication capability in compact form. This article addresses the communication issues between power electronic building blocks. A study case of Inter PEBB communication is described, based on two-optical ring topology and the possibility of complete implementation in a single FPGA for slave nodes.

Automotive Quality Universities – AQU – Integration of Modular Content into the Higher Education Studies

This paper introduces and discuss the integration of originally modular VET course AQUA (original idea about integrating teaching of Automotive SPICE, Functional Safety and Six Sigma content) into the higher education studies. The goal is to integrate industry courses to higher education learning, provide certification and examination appropriate for the higher education learning without extensive practical experience and thus prepare the students for their future jobs and trainings in automotive development in these fields. An idea about combination of industry and higher education levels learning, certification and examination is presented. Example of possibilities and experiences of integrated teaching from the universities involved in Automotive Quality Universities (AQU) project is also presented and discussed.

Functional safety in power electronics converters

Modern systems are becoming ever more complex and, thus, the possibility of failures in their operation is also growing. The complexity makes it practically impossible to make the hardware and software error-free without the special effort invested in the design process. Recently, a design methodology with the objective to avoid unacceptable risk of physical injury or of damage to the health of people, named Functional Safety, has been gaining importance. The paper presents the basics of the design process to be applied for the development of electrical / electronic / programmable electronic devices to be applied in safety critical applications.

Microinverter with pulse-density modulated HFAC-link and active decoupling circuit

This paper proposes a pulse-density modulated flyback-based microinverter with high-frequency ac link and active decoupling circuit. The converters structure and basic operating principle are analyzed. The advantages of utilizing an active decoupling circuit and the demand for using pulse-density modulation are explained. The operation of the proposed microinverter was verified by experiment.