高压大容量光伏系统新方案研究

A NOVEL SCHEME FOR PV SYSTEM WITH HIGH VOLTAGE AND LARGE CAPACITY

针对并网电压10～35kV容量10MW以上的光伏系统,提出一种基于多重化技术的新方案。系统中的DC/DC变换由多个功率单元并联,各功率单元由光伏电池阵列和多重升压斩波器组成,系统中的DC/AC变换等效为电压源和电流源串联,电压源由方波逆变器和变压器组成,电流源由PWM逆变器组成。仿真结果显示了此新方案应用于高压大容量光伏系统时的优越性能。

A novel scheme based on muhipulse technology was proposed for PV system with high voltage and large capacity. The power conversion of PV system is divided into two stages, i.e. DC/DC power conversion and DC/AC power conversion. In DC/DC stage, many power units are connected in parallel, each one of which includes a PV array and an interleaved boost converter that controlled by muhipulse technology of carrier phase-phifting. The DC/ AC power conversion is equivalent to a voltage source in series with a current source. Square wave inverters together with transformers are employed for the voltage source, which is controlled by multipulse technology of square wave superposition. PWM inverters are employed for the current source. The simulated results show excellent perform- ance of a high-voltage large-capacity PV system that adopts the proposed scheme.