Control and Intelligent Optimization of a Photovoltaic (PV) Inverter
An important technique to address the issue of stability and reliability of PV systems is optimizing converters'' control. Power converters'' control is intricate and affects the
Performance and stability analysis of single-phase grid
PV inverter system considering the PLL dynamics and resonance frequency, for the frequency range of interest, i.e., !<<2 fres, Cf does not in uence the inverter output current, and iinv = ig
Robust Suppression Strategy for Photovoltaic Grid
In this paper, in response to the problem of grid-connected resonance of the cluster inverter in a 200 MW large photovoltaic power station, a corresponding equivalent mathematical model was established based on the
Harmonics in Photovoltaic Inverters & Mitigation Techniques
PV inverters use semiconductor devices to transform the DC power into controlled AC power by using Pulse Width Modulation (PWM) switching. Resonance: When a harmonic current ˚ow
A review on modulation techniques of Quasi-Z-source inverter for
Additionally, ZSI can reliably work with a wide range of DC input voltage generated from PV sources. So, ZSIs are widely implemented for distributed generation systems and electric
Damping Method of Current Source Grid-Connected Photovoltaic Inverters
The circuit topology of the current source photovoltaic grid-connected inverter is shown in Fig. 1 [] the figure, u dc is the output voltage of the photovoltaic cell, L dc is the DC
Modeling and Analysis of Common-Mode Resonance in Multi-Parallel PV
With increasing penetration of renewable energy sources into distributed power systems, multi-parallel inverters are commonly employed in the interface to the utility grid,
Adaptive control technique for suppression of
Equation clearly shows that the harmonic impedance, and thus resonance phenomena, of the PV inverter system, is a complex function of the LCL filter components, grid impedance, PWM and current controller
Adaptive control technique for suppression of resonance in grid
even when individual PV inverter units have initially been commissioned to comply with the regulations. For this reason, the grid-connected PV inverter should ideally be designed to
6 FAQs about [ Ground resonance of photovoltaic inverter]
What is the resonance mechanism of photovoltaic grid-connected system?
The resonance mechanism of photovoltaic grid-connected system is analyzed based on frequency domain analysis method. The notch filter is added into the active damping control method, and the active damping of the system is enhanced by using the notch characteristics.
Why does a PV inverter have a series parallel resonance?
When the PV inverter is connected to the grid, series–parallel resonance may occur due to the dynamic interaction between multiple inverters operating in parallel and between the PV inverter and the grid impedance. Consequently, this leads to changes in the output voltage harmonic characteristics of the PV plant.
What is 'harmonic resonance' in grid-connected inverters?
On the basis of the traditional concept of ‘circuit resonance,’ the resonance in grid-connected inverters has been analyzed [25, 26]. However, the circuit resonance is not very helpful for analyzing system stability or harmonic amplification. In this paper, a new resonance concept is proposed which is called ‘harmonic resonance.’
Why do inverter-grid systems have a resonance phenomenon?
In inverter-grid systems, some studies have pointed out that a resonance phenomenon can arise when the inverter output impedance matches the grid impedance, due to various grid impedances [20, 21, 22, 23]. In addition, frequency-varying resonances were analyzed in . Consequently, the harmonics in the grid current can be inordinate.
How many resonance peaks are there in a photovoltaic grid-connected system?
1. There are usually two resonance peaks in photovoltaic grid-connected system, one of which is the natural resonance peak produced by LCL filter. The other is the coupling resonance peak formed by the parallel connection of multiple inverters and the impedance coupling of the power grid.
Is there an equivalent impedance model for a grid-connected inverter?
In this paper, an equivalent impedance model of a grid-connected inverter is established based on the traditional dual-control-loop strategy. Then, two kinds of resonance are introduced, i.e., circuit resonance based on zero resistance and harmonic resonance based on minimum impedance.