DSP Implementation of a Real-Time Boost Converter Simulator Handling Inter-step Switching Delay
Felipe Novaes Francis Dicler1; Matheus Soares da Silva1; Gustavo Figueiredo Gontijo1; Thiago Cardoso Tricarico1; Marcello da Silva Neves1; Mauricio Aredes1; Luis Guilherme Barbosa Rolim2
1 LEMT-COPPE-UFRJ; 2 LAFAE-COPPE-UFRJ
Baixar PDF doi:10.20906/CPS/CBA2018-1247
Resumo
This paper introduces the development and implementation of a boost converter real time simulator dealing with inter-step switching delays, which occur due to the different time steps and resulting asynchronism between the digital controller that outputs switch firing signals and the microprocessor that simulates the boost converter. It is shown that, if left unaccounted for, these delays can cause inaccuracy levels such as to make both closed and open loop simulations unreliable. In order to avoid this, a time step changing algorithm is implemented. This algorithm is based on the detection of switching orders and a subsequent correction routine to account for the delay by calculating the system state at the detection moment. The boost circuit is modeled through the differential equations of each possible converter state-configuration (that is, each mode of the circuit). The equations are then numerically solved by Backward Euler method.The real-time platform is composed by two Texas Instruments DSPs, the first one simulating the converter and the other implementing the Proportional-Integral control system.The implemented algorithm works as intended and allows for an increase in the converter simulation time step to values which would previously give incorrect results.
Palavras-chave: Discrete event simulation; Real time simulation; Inter-step time switching; Hardware-in-the-loop