研究目的
To improve a single-phase transformerless inverter for PV systems by eliminating leakage current and enabling reactive power capability through modifications in topology and modulation techniques.
研究成果
The modified inverter topology with clamping and revised modulation successfully achieves constant CMV, eliminates leakage current, and enables reactive power generation. THD is reduced by 82%, but efficiency decreases by up to 2% at higher switching frequencies due to conduction losses. The approach is suitable for next-generation PV inverters requiring reactive power support.
研究不足
The efficiency of the system decreases with reactive power generation due to increased conduction losses from the bidirectional current path. The study is simulation-based, so real-world validation is not included. The use of SiC MOSFETs may involve higher costs, and the topology modifications add complexity.
1:Experimental Design and Method Selection:
The study involves modifying an existing H6 transformerless inverter topology with a clamping method to achieve constant common mode voltage (CMV) and eliminate leakage current. A modified unipolar PWM modulation technique is developed to create a bidirectional current path for reactive power generation. Simulations are conducted to evaluate performance.
2:Sample Selection and Data Sources:
The system parameters are defined, including input voltage, grid voltage, frequency, switching frequencies, capacitors, and power levels. No specific datasets are mentioned; simulations are based on theoretical models.
3:List of Experimental Equipment and Materials:
The inverter uses switches (e.g., S1-S7), DC link capacitors, and SiC MOSFETs. Specific models or brands are not provided in the paper.
4:Experimental Procedures and Operational Workflow:
Simulations are performed using PSIM and MATLAB/SIMULINK software. The workflow includes setting up the inverter with parameters, applying modulation techniques, and analyzing CMV, leakage current, THD, and efficiency under different conditions (e.g., unity and non-unity power factors, switching frequencies).
5:Data Analysis Methods:
Data is analyzed for CMV clamping, leakage current elimination, THD reduction, and efficiency calculations based on the California Energy Commission (CEC) formula. Results are compared between conventional and modified techniques.
独家科研数据包,助您复现前沿成果,加速创新突破
获取完整内容