光伏逆变效率与开关控制脉冲的关系

Relationship between inversion efficiency and switching control pulse

为了提高光伏逆变的效率,更好地利用太阳能,分析了正弦脉宽调制技术(SPWM),得出了SPWM波作为开关控制脉冲时光伏逆变的效率,分析了正弦脉宽调制中正弦调制波的幅度与三角波载波幅度的不同比值所对应的开关控制脉冲不同的波形形式,提出了一种新的准SPWM波,得出了光伏逆变效率与控制脉冲调制幅度比的关系,结果表明光伏逆变效率随调制幅度比的增大而提高,且当调制幅度比增大到1.9时逆变效率达到最大,当继续增大调制幅度比时逆变效率会变小,因此得出可以通过改变逆变电路的开关控制脉冲的调制幅度比来提高逆变效率,从而使逆变效率达到最大.

In order to improve the efficiency of photovoltaic inverter,making full use of solar energy,this paper analyzes the sinusoidal pulse width modulation（SPWM）technology,obtaining the inversion efficiency of photovoltaic inverter when the SPWM wave is used as switching control pulse,and analyzing the different wave forms of switching control pulse corresponding to different ratios of the sinusoidal modulation wave amplitude and the triangle carrier wave amplitude of sinusoidal pulse width modulation,putting forward a new quasi SPWM waves,obtaining the relationship between inversion efficiency and the modulation amplitude ratio of the switching control pulse.The results show that the inversion efficiency will increase as the modulation amplitude ratio increases;and the inversion efficiency will reach the maximum when the modulation amplitude ratio increases to 1.9;the inversion efficiency will decrease when the modulation amplitude ratio continues to increase.Finally,it is concluded that we could switch to change the modulation amplitude ratio of the switching control pulse of inversion circuit to improve the inversion efficiency so that the inversion efficiency is maximized.