Computer-Aided Design of Digital Compensators for DC/DC Power Converters

Digital control of high-frequency power converters has been used extensively in recent years, providing flexibility, enhancing integration, and allowing for smart control strategies. The core of standard digital control is the discrete linear compensator, which can be calculated in the frequency dom...

Full description

Bibliographic Details
Main Authors: Pablo Zumel, Cristina Fernández, Marlon A. Granda, Antonio Lázaro, Andrés Barrado
Format: Article
Language:English
Published: MDPI AG 2018-11-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/11/12/3251
_version_ 1811186313990242304
author Pablo Zumel
Cristina Fernández
Marlon A. Granda
Antonio Lázaro
Andrés Barrado
author_facet Pablo Zumel
Cristina Fernández
Marlon A. Granda
Antonio Lázaro
Andrés Barrado
author_sort Pablo Zumel
collection DOAJ
description Digital control of high-frequency power converters has been used extensively in recent years, providing flexibility, enhancing integration, and allowing for smart control strategies. The core of standard digital control is the discrete linear compensator, which can be calculated in the frequency domain using well-known methods based on the frequency response requirements (crossover frequency, <i>f<sub>c</sub></i>, and phase margin, <i>PM</i>). However, for a given compensator topology, it is not possible to fulfill all combinations of crossover frequency and phase margin, due to the frequency response of the controlled plant and the limitations of the compensator. This paper studies the performance space (<i>f<sub>c</sub></i>, <i>PM</i>) that includes the set of achievable crossover frequencies and phase margin requirements for a combination of converter topology, compensator topology, and sensors, taking into account the effects of digital implementation, such as delays and limit cycling. Regarding limit cycling, two different conditions have been considered, which are related to the design of the digital compensator: a limited compensator integral gain, and a minimum gain margin. This approach can be easily implemented by a computer to speed up the calculations. The performance space provides significant insight into the control design, and can be used to compare compensator designs, select the simplest compensator topology to achieve a given requirement, determine the dynamic limitations of a given configuration, and analyze the effects of delays in the performance of the control loop. Moreover, a figure of merit is proposed to compare the dynamic performance of the different designs. The main goal is to provide a tool that identifies the most suitable compensator design in terms of the dynamic performance, the complexity of the implementation, and the computational resources. The proposed procedure to design the compensator has been validated in the laboratory using an actual DC/DC converter and a digital hardware controller. The tests also validate the theoretical performance space and the most suitable compensator design for a given dynamic specification.
first_indexed 2024-04-11T13:43:27Z
format Article
id doaj.art-df3f5f712caf46269ec207356886206f
institution Directory Open Access Journal
issn 1996-1073
language English
last_indexed 2024-04-11T13:43:27Z
publishDate 2018-11-01
publisher MDPI AG
record_format Article
series Energies
spelling doaj.art-df3f5f712caf46269ec207356886206f2022-12-22T04:21:10ZengMDPI AGEnergies1996-10732018-11-011112325110.3390/en11123251en11123251Computer-Aided Design of Digital Compensators for DC/DC Power ConvertersPablo Zumel0Cristina Fernández1Marlon A. Granda2Antonio Lázaro3Andrés Barrado4Grupo de Sistemas Electrónicos de Potencia, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, 28911 Leganes, Madrid, SpainGrupo de Sistemas Electrónicos de Potencia, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, 28911 Leganes, Madrid, SpainGrupo de Sistemas Electrónicos de Potencia, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, 28911 Leganes, Madrid, SpainGrupo de Sistemas Electrónicos de Potencia, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, 28911 Leganes, Madrid, SpainGrupo de Sistemas Electrónicos de Potencia, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, 28911 Leganes, Madrid, SpainDigital control of high-frequency power converters has been used extensively in recent years, providing flexibility, enhancing integration, and allowing for smart control strategies. The core of standard digital control is the discrete linear compensator, which can be calculated in the frequency domain using well-known methods based on the frequency response requirements (crossover frequency, <i>f<sub>c</sub></i>, and phase margin, <i>PM</i>). However, for a given compensator topology, it is not possible to fulfill all combinations of crossover frequency and phase margin, due to the frequency response of the controlled plant and the limitations of the compensator. This paper studies the performance space (<i>f<sub>c</sub></i>, <i>PM</i>) that includes the set of achievable crossover frequencies and phase margin requirements for a combination of converter topology, compensator topology, and sensors, taking into account the effects of digital implementation, such as delays and limit cycling. Regarding limit cycling, two different conditions have been considered, which are related to the design of the digital compensator: a limited compensator integral gain, and a minimum gain margin. This approach can be easily implemented by a computer to speed up the calculations. The performance space provides significant insight into the control design, and can be used to compare compensator designs, select the simplest compensator topology to achieve a given requirement, determine the dynamic limitations of a given configuration, and analyze the effects of delays in the performance of the control loop. Moreover, a figure of merit is proposed to compare the dynamic performance of the different designs. The main goal is to provide a tool that identifies the most suitable compensator design in terms of the dynamic performance, the complexity of the implementation, and the computational resources. The proposed procedure to design the compensator has been validated in the laboratory using an actual DC/DC converter and a digital hardware controller. The tests also validate the theoretical performance space and the most suitable compensator design for a given dynamic specification.https://www.mdpi.com/1996-1073/11/12/3251power convertersdigital controldesign spacefrequency domain
spellingShingle Pablo Zumel
Cristina Fernández
Marlon A. Granda
Antonio Lázaro
Andrés Barrado
Computer-Aided Design of Digital Compensators for DC/DC Power Converters
Energies
power converters
digital control
design space
frequency domain
title Computer-Aided Design of Digital Compensators for DC/DC Power Converters
title_full Computer-Aided Design of Digital Compensators for DC/DC Power Converters
title_fullStr Computer-Aided Design of Digital Compensators for DC/DC Power Converters
title_full_unstemmed Computer-Aided Design of Digital Compensators for DC/DC Power Converters
title_short Computer-Aided Design of Digital Compensators for DC/DC Power Converters
title_sort computer aided design of digital compensators for dc dc power converters
topic power converters
digital control
design space
frequency domain
url https://www.mdpi.com/1996-1073/11/12/3251
work_keys_str_mv AT pablozumel computeraideddesignofdigitalcompensatorsfordcdcpowerconverters
AT cristinafernandez computeraideddesignofdigitalcompensatorsfordcdcpowerconverters
AT marlonagranda computeraideddesignofdigitalcompensatorsfordcdcpowerconverters
AT antoniolazaro computeraideddesignofdigitalcompensatorsfordcdcpowerconverters
AT andresbarrado computeraideddesignofdigitalcompensatorsfordcdcpowerconverters