Effects of Power Tracking Algorithms on Lifetime of Power Electronic Devices Used in Solar Systems

Abstract

Abstract:In photovoltaic solar energy systems, power management algorithms (PMAs), usually called maximum power point tracking (MPPT) algorithms, are widely used for extracting maximum available power at every point in time. However, tracking the maximum power has negative effects on the availability of solar energy systems. This is due, mainly, to the created disturbances and thermal stresses on the associated power electronic converters (PECs). This work investigates the effects of PMA on the lifetime consumption, thermal stresses and failures on DC-DC converters used in solar systems. Firstly theoretical analysis and modelling of photovoltaic solar systems including converter's electro thermal characteristics were developed. Subsequently, experiments on photovoltaic solar systems were carried out using two different PMAs, namely, perturb and observe (P&O) and incremental conductance (IC). Real-time data was collected, under different operating conditions, including thermal behavior using thermal imaging camera and dSPACE. Converters' thermal cycling was found to be approximately 3 • C higher with the IC algorithm. The steady state temperature was 52.7 • C, for the IC while it was 42.6 • C for P&O. Although IC algorithm offers more accurate power management tool, it causes more severe thermal stresses which, in this study, has led to approximately 1.4 times greater life consumption compared to P&O.

Open- and Short-Circuit Fault Identification for a Boost dc/dc Converter in PV MPPT Systems

“…Here, the FI signalδ f can be observed in the Figure 7a. As can be seen in Figure 7, the FI signal at steady-state decreases up to approximately∆ f = −75.0, as expected from the result given in (9). Once more, a constant fault profile can be visualized from Figure 7.…”

“…In addition, the steady-state value for∆ f under SOCSF can be verified departing from Equations (7) and (9). Finally, a block diagram of the FI system suggested in this paper is illustrated in Figure 2.…”

“…On the other hand, switching devices are the most fragile components in PEC [7], which are mainly affected by thermal stress conditions [8]. Recently, the negative effects of conventional MPPT algorithms on the thermal stresses and reliability of PEC were presented in [9]. Therefore, a fault identification (FI) system for short-and open-circuit switch faults (SOCSF) in MPPT systems would be useful to increase the efficiency and reliability of PV systems.…”

Using an Integrated Script Control Unit (ISCU) to Assist the Power Electronics Education

“…dSPACE is one set of platform comprised of software and hardware, which can eliminate the process of designing the relevant PCB boards [35,36]. The hardware system consists of a digital processor and abundant I/O interfaces, and the software system involves the whole toolkits for automatic generation, load, execution, and debugging of the source codes.…”

Mejora de la Vida Útil en los Módulos de Electrónica de Potencia de un BLDCM Mediante la Optimización de un Control Difuso

“…En (Qin y Wang et al, 2015) se presentan estrategias de modulación SVPWM y DPWM, para el convertidor de potencia en un aerogenerador, esto para reducir las oscilaciones debidas a las variaciones de viento. (Andresen y Ma et al 2018), adicionalmente estas estrategias de control también consideran un control térmico activo como en (Murdock y Torres et al, 2006), así bajo estas consideraciones se puede manipular la relación entre las pérdidas de potencia debidas a la frecuencia de conmutación y la corriente de salida, lo cual se puede traducir en un incremento en el tiempo de vida (Held et al, 1997;Bayerer et al, 2008;ABB, 2014;Ma et al, 2016;Parker et al, 2016;Batunlu et al, 2016). Así, el diseño del controlador tiene un rol importante si se desea incrementar el tiempo de vida de los semiconductores, las pedidas de potencia y las condiciones de operación de los semiconductores deben ser tomadas en cuenta en el diseño del controlador (Held et al, 1997;Bayerer et al, 2008;Infineon, 2012;Fuji Electric, 2015).…”