The Heuristic Dynamic Programming Approach in Boost Converters

In this study, a heuristic dynamic programming controller is proposed to control a boost converter. Conventional controllers such as proportional-integral-derivative (PID) or proportional-integral (PI) are designed based on the linearized small-signal model near the operating point. Therefore, the performance of the controller during the start-up, the load change, or the input voltage variation is not optimal since the system model changes by varying the operating point. The heuristic dynamic programming controller optimally controls the boost converter by following the approximate dynamic programming. The advantage of the HDP is that the neural network-based characteristic of the proposed controller enables boost converters to easily cope with large disturbances. An HDP with a well-trained critic and action networks can perform as an optimal controller for the boost converter. To compare the effectiveness of the traditional PI-based and the HDP boost converter, the simulation results are provided

The Voltage Regulation of a Buck Converter using a Neural Network Predictive Controller

In this paper, a neural network predictive controller (NNPC) is proposed to control a buck converter. Conventional controllers such as proportional-integral (PI) or proportional-integral-derivative (PID) are designed based on the linearized small-signal model near the operating point. Therefore, the performance of the controller in the start-up, load change, or reference change is not optimal since the system model changes by changing the operating point. The neural network predictive controller optimally controls the buck converter by following the concept of the traditional model predictive controller. The advantage of the NNPC is that the neural network system identification decreases the inaccuracy of the system model with inaccurate parameters. A NNPC with a well-trained neural network can perform as an optimal controller for the buck converter. To compare the effectiveness of the traditional buck converter and the NNPC, the simulation results are provided

An Interleaved High Step-Up DC-DC Converter with Coupled Inductor and Built-In Transformer for Renewable Energy Applications

This paper introduces an interleaved high step-up DC-DC converter with high voltage gain, low voltage stresses on the switches, low current stresses on the components, and continuous input current with low ripple, all of which are beneficial for the renewable energy (RE) applications. The proposed converter is based on the integration of three voltage-boosting (VB) methods: coupled inductor (CI), built-in transformer (BIT), and switched-capacitor (SC) cells. The energies of the leakage inductances of the CIs and BIT are absorbed and recirculated to the output side, which further extends the voltage gain. In addition, the current-falling rates of the diodes are controlled by the leakage inductances, which leads to the reduced reverse-recovery losses of the diodes. The operating stages, steady-state analysis, and a comparison with similar existing topologies are presented in this paper. Furthermore, the performance of the proposed converter is verified through the experimental results of a 200-W prototype with an output voltage of 400 V and a voltage gain of 30

An Interleaved High Step-Up DC-DC Converter with Built-In Transformer-Based Voltage Multiplier for DC Microgrid Applications

This paper proposes a high step-up DC-DC converter with a built-in transformer (BIT)-based voltage multiplier (VM) that is suitable for integrating low-voltage renewable energy sources into a DC microgrid. A three-winding BIT is combined with the switched-capacitor (SC) cells to extend the voltage gain and reduce the voltage stress on the switches. The current-falling rates of the diodes are controlled by the leakage inductances of the BIT, alleviating the reverse-recovery problem of the diodes. The operating modes and steady-state analysis are presented. Additionally, the validity of the proposed converter is confirmed by the simulation and experimental results of a 400 W converter with an input voltage of 20 V and output voltage of 400 V. Moreover, a comparison study is presented to verify the superiority of the proposed converter over the closest existing topologies in the literature

A High Step-Up Dc-Dc Converter using a Three Winding Coupled Inductor for Photovoltaic to Grid Applications

A dual-switch high step-up DC-DC converter topology is proposed in this paper. The proposed topology uses two power switches, a three-winding coupled inductor (TWCI), and voltage multiplier cells to provide a high voltage gain. Furthermore, the voltage stresses on power semiconductor switches are low, resulting in lower switching and conduction losses. Moreover, the common electrical ground is preserved in this topology, making it a suitable candidate for photovoltaic (PV) to grid systems. The operating modes and steady state analysis of the proposed converter are presented, and a comparative study is carried out to demonstrate advantages of the proposed topology over the existing topologies. Finally, the simulation results of the proposed topology are presented using PLECS software along with the experimental results for a 200 W, 30 V to 400 V laboratory setup