A method for controlling output current of photovoltaic inverter under asymmetrical fault conditions
A photovoltaic inverter and output current technology, applied in photovoltaic power generation, electrical components, circuit devices, etc., can solve problems such as not comprehensive consideration, emphasis on harmonic suppression or power fluctuation, etc.
Active Publication Date: 2018-09-28
STATE GRID HENAN ELECTRIC POWER ELECTRIC POWER SCI RES INST +1
View PDF6 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0004] The purpose of the present invention is to provide a photovoltaic inverter output current control method under asymmetrical fault conditions to solve the problem that the existing control strategies of photovoltaic inverters under asymmetrical fault conditions mainly focus on harmonic suppression or power fluctuations. point, rather than comprehensive consideration
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0041] A method for controlling the output current of a photovoltaic inverter under an asymmetrical fault condition according to the present invention comprises the following steps:
[0042] Step A: Build a photovoltaic array model;
[0043] The preferred solution is that the photovoltaic array model of the present invention adopts the 5-parameter photovoltaic cell model proposed by the U.S. SEL Laboratory (Solar Energy Laboratory), and the equivalent circuit of the 5-parameter photovoltaic cell model is a current source connected in parallel with a reverse diode and an equal The effective parallel resistance, and then an equivalent series resistance in series; the 5-parameter photovoltaic cell model contains 5 parameters in total: the photogenerated current I pv , Diode reverse saturation leakage current I 0 , ideality factor a, equivalent parallel resistance R p and equivalent series resistance R s ; The output characteristic I-V equation of the 5-parameter photovoltaic c...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a photovoltaic inverter output current control method in an asymmetric fault condition. The method comprises the following steps: A, a photovoltaic array model is built; B, positive, negative and zero-sequence voltage components are extracted from three-phase voltage outputted by the photovoltaic inverter; C, based on a multi-parameter photovoltaic inverter output current control strategy, output active power and reactive power fluctuation rates and an output current total harmonic distortion rate of the photovoltaic inverter are analyzed; and D, in a stationary coordinate system, a proportional resonant PR controller is used for designing the grid-connected current control structure of the photovoltaic inverter. The proportional resonant controller is used in the stationary coordinate system to realize simultaneous output current positive and negative-sequence components of the photovoltaic inverter, and the problem that the existing photovoltaic inverter control strategy in the asymmetric fault condition mainly focuses on either harmonic suppression or power fluctuation rather than whole aspects can be solved.
Description
technical field [0001] The invention relates to the field of photovoltaic power generation control, in particular to a method for controlling output current of a photovoltaic inverter under asymmetrical fault conditions. Background technique [0002] Due to the occurrence of three-phase asymmetrical faults in the power grid, there are positive and negative sequence components and harmonic components in the grid voltage at the same time; as we all know, the negative sequence component will cause double frequency fluctuations in the grid voltage and current, and even cause output current Waveform distortion will increase the harmonic loss of the inverter; at the same time, it will also cause the output power of the inverter to fluctuate, thereby affecting the maximum power tracking control of the photovoltaic cell and reducing the conversion efficiency of the photovoltaic cell. Instability and burn the inverter. [0003] At present, most of the control strategies of photovolt...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): H02J3/38
CPCH02J3/383Y02E10/56
Inventor 李琼林王忠强代双寅刘书铭张博唐钰政朱明丽
Owner STATE GRID HENAN ELECTRIC POWER ELECTRIC POWER SCI RES INST