Constant power load stabilization

This paper proposes a high-performance control strategy for dc–dc converters supplying combined loads (constant current/power, and/or linear loads). This strategy combines a feedback law with a feedforward compensation. The feedback law is based on full feedback linearization, which guarantees that zero dynamics are avoided. To design a single controller for the three basic converter topologies (i.e., buck, boost and buck–boost), a unified model for these converters is introduced. From the resulting combined control law, the specific control law for each type of converter can be obtained by setting three constant coefficient to 0 or 1. The feedforward compensation is based on the estimated values of the load obtained via a nonlinear observer. The main advantage of this unified approach is that it is implemented by using a single algorithm which can be executed in a dedicated hardware, for instance, a single integrated circuit, providing a unified solution for the control of the mentioned topologies. The good performance of the proposed scheme is verified through simulations and tested via experimental application cases, concluding that this is a good unified solution to control dc–dc converters used in microgrid applications.

Section: Introductionmentioning

confidence: 99%

Modeling and Nonlinear Control of dc–dc Converters for Microgrid Applications

Solsona

Jorge²,

Busada³

2022

Sustainability

“…Uma CPLé caracterizada por ter uma dinâmica mais rápida que o feeder onde as variações instantâneas de potência diminuem a estabilidade do sistema (Singh et al, 2017). Mosskull (2018) explica os efeitos que a CPL pode ocasionar em um sistema de distribuição CC, em seguida apresenta diversas técnicas para mitigar estes efeitos via amortecimento passivo ou ativo e pelo uso de técnicas de controle lineares Mosskull (2018). Riccobono and Santi (2014) e Dragicevic et al (2016) realizam uma revisão de critérios de estabilidade aplicados a sistemas de distribuicão CC, onde através do conhecimento das características da carga, realizam o projeto do feeder.…”

Section: Introductionunclassified

Estratégias de controle aplicadas para mitigação de oscilações decorrentes de CPL em uma microrrede CC do tipo boost-buck

Medeiros

Anais Do Congresso Brasileiro De Automática 2020

et al. 2020

A utilização de fontes renováveis de energia em paralelo com o desenvolvimento da eletrônica de potência possibilitou o desenvolvimento de microrredes CC. Nesse sentido este trabalho realiza uma revisão de estratégias de controle clássicas aplicadas para mitigar oscilações de um conversor boost conetado a uma CPL buck, onde essas estratégias são aplicadas ao conversor boost que irá operar como um regulador de tensão. As metodologias escolhidas utilizam estrutura de realimentação de saída, através da solução da equação Diofantina e lugar geométrico das raízes, e estruturas de realimentação de estados, através da solução da equação de Lyapunov e da solução da equação de Riccati.

“…Microgrids are composed of feeders that must maintain a constant voltage of DC bus to which are connected DC loads as in (Marcillo et al, 2019;Singh et al, 2017). The behavior of the constant power loads (CPL) in the connection with the DC bus is studied in (Mosskull, 2018), where it is observed oscillations in the feeder due to the constant consumption of power of the CPL that causes a variation of current and voltage for the maintenance of the constant power. These variations result in the occurrence of a negative resistance in which its effects are observed in the form of oscillations in the DC bus (Marcillo et al, 2019;Singh et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

“…Ensuring the stability of the microgrid is fundamental to the proper functioning of the system and in (Riccobono and Santi, 2014) it is shown criteria that guarantee the stability of the system among which stands out the criterion of Middlebrook that ensure the DC microgrid stability if the output feeder impedance is less than the input impedance of CPL. The mitigation of CPL oscillations is already investigated in (Mosskull, 2018) that shows the relationship between good damping and small power variations, and in (Marcillo et al, 2019), that uses robust control strategies to reduce the oscillation effects. This paper proposes a DC microgrid model where the feeder is represented by a boost converter while the CPL is designed through a buck converter.…”

Section: Introductionmentioning

confidence: 99%

Comparative study of control strategies for oscillation damping in DC microgrids

Medeiros

Anais Do 14º Simpósio Brasileiro De Automação Inteligente

et al. 2019

Nowadays, the use of converters is attracting increasing attention due to diversification of electric power sources. In particular, DC-DC converters are used to ensure the stability in the DC supply responsible for feeding a DC microgrid with constant voltage. Thus, classical and modern controls methodologies are used to ensure the stability of the feed system when connected to a constant power load (CPL). This paper compares control methodologies for pole allocation using Diophantine equation, root locus, linear-quadratic regulator and the Lyapunov equation by using performance indices as integral of square error (ISE), integral of square weighted by time (ISET) and integral of square of control (ISSC).