Yuncong Jiang

Adaptive Step Size With Adaptive-Perturbation-Frequency Digital MPPT Controller for a Single-Sensor Photovoltaic Solar System

This paper presents a load-current-based maximum power point tracking (MPPT) digital controller with an adaptive-step-size and adaptive-perturbation-frequency algorithm. Only one sensor is needed in the controller circuitry since the MPPT controller is only utilizing the load current information. By utilizing a variable step-size algorithm, the speed, accuracy, and efficiency of the PV system MPPT are improved when compared to the fixed step-size load-current-based algorithm. Furthermore, the proposed adaptive algorithm utilizes a novel variable perturbation frequency scheme which further improves the controller speed. The concept and operation of the load-current adaptive-step-size and adaptive-perturbation-frequency MPPT controller are presented, analyzed, and verified by results obtained from a proof-of-concept experimental prototype.

Matlab/Pspice hybrid simulation modeling of solar PV cell/module

The power generated by solar photovoltaic (PV) module depends on surrounding irradiance, temperature and shading conditions. Under partial shading conditions (PSC) the power from the PV module can be dramatically reduced and maximum power point tracking (MPPT) control will be affected. This paper presents a hybrid simulation model of PV cell/module and system using Matlab®/Simulink® and Pspice®. The hybrid simulation model includes the solar PV cells and the converter power stage and can be expanded to add MPPT control and other functions. The model is able to simulate both the I-V characteristics curves and the P-V characteristics curves of PV modules under uniform shading conditions (USC) and PSC. The model is used to study different parameters variations effects on the PV array. The developed model is suitable to simulate several homogeneous or/and heterogeneous PV cells or PV panels connected in series and/or in parallel.

Improved solar PV cell Matlab simulation model and comparison

This paper presents an improved mathematical and simulation model for Solar Photovoltaic (PV) cells and compares it to an existing model. The model is able to simulate both the I-V characteristics curves and the P-V characteristics curves. The model is used to study different parameters variations effects on the PV array including operating temperature and solar irradiation level The results of the PV characteristics curves are compared to the curves provided by BPSX150 PV module datasheet. Matlab®/Simulink® software is used to implement the models and obtain the simulation results.

Study and evaluation of load current based MPPT control for PV solar systems

Because the power from Photovoltaic (PV) solar arrays depends on the array operating and surrounding conditions, it is beneficial to implement a maximum power point tracking (MPPT) technique to enlarge the amount of output power. There are several MPPT concepts and algorithms presented in the literature. This paper evaluates a load/output current based MPPT (LOC-MPPT) technique using P&O algorithm which requires the load current sensing only as the control variable. The LOC-MPPT technique is experimentally evaluated in this paper with different perturbation step sizes using a PV solar system prototype. The effect of the perturbation step size value on controller speed and accuracy is experimentally analyzed.

Energy Efficient Fine-grained approach for Solar Photovoltaic Management System

The papers main objective is to develop an Energy Efficient Solar Photovoltaic (PV) Management System that especially addresses the partial shading effects, among other cells mismatches, in a solar PV array/panel. In the presented Fine-Grained (FG) system, each single solar PV cell or a group of solar PV cells has its own MPPT (Maximum Power Point Tracking) controller and the power converter associated with it. The FG MPPT PV solar power management approach can ensure true maximum power point tracking (extract higher amount of power) under unified illumination conditions and under partial shading conditions. While the FG MPPT approach can have digital or/and analog implementations, this paper focuses on proposing an analog circuit implementation to reduce cost and size and to simplify system integration. Orcad/Pspice® simulation results verify the operation and advantages of the proposed FG system and circuits.

AC PV solar system distributed architecture with maximum power point tracking

Mismatching effects are major drawbacks existing in todays photovoltaic (PV) solar systems. To improve power system stability and energy conversion efficiency, distributed maximum power point tracking (DMPPT) techniques are developed. In this paper, single-stage DMPPT power management DC-AC inverter architecture (SS-AC-DMPPT) is presented and verified by Matlab®/Simulink® simulation model results. In the SS-AC-DMPPT PV solar system architecture, multiple inverters are connected in series in order to yield higher AC output voltage to the load such as the grid, each inverter is directly connected to a PV solar panel or cell, and MPPT control is performed by each inverter.

Single-cell photovoltaic with integrated converter

Dust and shade have severe effects on the output of Photovoltaic (PV) modules especially in urban area. This problem is a major issue in order to achieve low cost and high efficiency PV system. This paper proposes a Power Conditioning System (PCS) suitable for PV module using single-cell architecture. The Ripple Correlation Control (RCC) has been employed to harvest the maximum cell power with 1 MHz switching frequency. This high switching frequency gives the advantage of decreasing the whole PCS components size drastically through applying integration techniques. This also enables to attach the developed integrated PCS into the PV cell itself. The paper provides PCS components design and simulation results as well as demonstrates the proposed idea.

Load current based analog MPPT controller for PV solar systems

Analog maximum power point tracking (MPPT) controller circuit for photovoltaic solar panels/cells is an attractive solution due to its low cost and simple implementation. The paper presents an analog Maximum Power Point Tracking (MPPT) controller for a Photovoltaic (PV) solar system that utilizes the load current to achieve maximum output power from the solar panel. Compared to the existing MPPT controller circuitry which requires multiplication of the sensed PV panel voltage and current to yield panel power, the cost and size of the proposed circuit are reduced. The tracking performance of the proposed MPPT controller is validated by simulation results. The proposed MPPT controller circuit can be further implemented by CMOS technology and fabricated on-chip to perform distributed maximum power point tracking (DMPPT) in PV system.

MPPT Control and Architecture for PV Solar Panel with Sub-Module Integrated Converters

Photovoltaic (PV) solar systems with series-connected module integrated converters (MICs) are receiving increased attention because of their ability to create high output voltage while performing local maximum power point tracking (MPPT) control for individual solar panels, which is a solution for partial shading effects in PV systems at panel level. To eliminate the partial shading effects in PV system more effectively, sub-MICs are utilized at the cell level or grouped cell level within a PV solar panel. This study presents the results of a series-output-connection MPPT (SOC-MPPT) controller for sub-MIC architecture using a single sensor at the output and a single digital MPPT controller (sub-MIC SOC-MPPT controller and architecture). The sub-MIC SOC-MPPT controller and architecture are investigated based on boost type sub-MICs. Experimental results under steady-state and transient conditions are presented to verify the performance of the controller and the effectiveness of the architecture.

Multiple solar panels maximum power point tracking using the output current

This paper focuses on developing an MPPT controller suitable for multiple PV panel maximum power points tracking. In the presented PV system MPPT controller, instead of sensing both the voltage and current from the PV panel, only the output current of the power converter following the solar array is sensed and used as the control variable in the P&O algorithm. This results in reduced cost and size. The controlled operation is tested and verified experimentally by using a proof-of-concept laboratory prototype.