# MPPT and SPPT Control for PV-Connected Inverters Using Digital Adaptive Hysteresis Current Control

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Digital Grid Router

## 3. Adaptive Hysteresis Current Control

_{o}of the inverter be controlled by switch devices S

_{1}and S

_{2}to track a given reference current i

_{ref}The adaptive hysteresis current control is employed as shown below [16].

## 4. Hysteresis Current Control for PV-Connected Inverter

#### 4.1. Algorithm for MPPT Control

#### 4.2. Algorithm for SPPT Control

## 5. Experimental Results

#### 5.1. Grid-Connected PV System

#### 5.2. Simple Model for PV Panel

_{DC}= V + RI.

#### 5.3. Experimental Results

_{g}= 1.1 mH, and C = 6.8 µF. The reference voltage of the DC bus ${V}_{dc\_ref}$ is set at 175 V. The analog/digital converter (ADC) has the sampling frequency of 4 MHz. The switching transistors in the inverter circuit are IGBT devices with the dead-time at 1.5 µ sec. The constant switching frequency in the adaptive hysteresis current control is at 20 kHz. The control algorithm is implemented on a FPGA board, which has a clock frequency of 160 MHz. The grid has an AC voltage of 100 V and frequency of 50 Hz. The DC power source of the PV model ${V}_{DC}$ in Figure 10 is at 250 V. The step-size $\delta i$ of the reference current is at 0.1 A.

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 12.**Responses of grid-connected and PV-connected inverters under MPPT control with $R=80\text{}\mathsf{\Omega}$.

**Figure 13.**Responses of grid-connected and PV-connected inverters under SPPT control with $R=80\text{}\mathsf{\Omega}$.

**Figure 14.**Responses of grid-connected and PV-connected inverters under MPPT control when the resistor $R$ changes from 60 W to 100 W.

**Figure 15.**Responses of grid-connected and PV-connected inverters under MPPT control when the resistor $R$ changes from 100 W to 60 W.

Resistor $\mathit{R}\text{}\left[\mathsf{\Omega}\right]$ | Measured Current $\mathit{I}\text{}\left[\mathbf{A}\right]$ | Measured Voltage $\mathit{V}\text{}\left[\mathbf{V}\right]$ | Measured Power $\mathit{P}\text{}\left[\mathbf{W}\right]$ | Calculated Power $\mathit{P}\text{}\left[\mathbf{W}\right]$ |
---|---|---|---|---|

100 | 1.19 | 131 | 155 | 156 |

80 | 1.38 | 140 | 194 | 195 |

60 | 1.87 | 136 | 254 | 260 |

Resistor $\mathit{R}\text{}\left[\mathsf{\Omega}\right]$ | Measured Current $\mathit{I}\text{}\left[\mathbf{A}\right]$ | Measured Voltage $\mathit{V}\text{}\left[\mathbf{V}\right]$ | Measured Power $\mathit{P}\text{}\left[\mathbf{W}\right]$ | Specified Power ${\mathit{P}}_{\mathit{s}}\text{}\left[\mathbf{W}\right]$ |
---|---|---|---|---|

100 | 0.9 | 161 | 145 | 150 |

80 | 0.76 | 191 | 144 | |

60 | 0.72 | 208 | 148 |

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**MDPI and ACS Style**

Nguyen-Van, T.; Abe, R.; Tanaka, K.
MPPT and SPPT Control for PV-Connected Inverters Using Digital Adaptive Hysteresis Current Control. *Energies* **2018**, *11*, 2075.
https://doi.org/10.3390/en11082075

**AMA Style**

Nguyen-Van T, Abe R, Tanaka K.
MPPT and SPPT Control for PV-Connected Inverters Using Digital Adaptive Hysteresis Current Control. *Energies*. 2018; 11(8):2075.
https://doi.org/10.3390/en11082075

**Chicago/Turabian Style**

Nguyen-Van, Triet, Rikiya Abe, and Kenji Tanaka.
2018. "MPPT and SPPT Control for PV-Connected Inverters Using Digital Adaptive Hysteresis Current Control" *Energies* 11, no. 8: 2075.
https://doi.org/10.3390/en11082075