单片机实现用脉冲宽度按正弦规律变化而和正弦波等效的PWM波形即SPWM波形控制逆变电路中开关器件的通断，使其输出的脉冲电压的面积与所希望输出的正弦波在相应区间内的面积相等，通过改变调制波的频率和幅值则可调节逆变电路输出电压的频率和幅值，进而控制逆变输出电压。(The singlechip realizes the switching of the switch device in the inverter circuit, which is controlled by the pulse width according to the sine law and the PWM waveform equivalent to the sinusoidal wave, that is, the SPWM waveform. The area of the output pulse voltage is equal to the desired output sine wave in the corresponding interval, and the frequency and amplitude of the variable modulation wave can be adjusted to the inverse. The frequency and amplitude of the output voltage of the circuit are changed to control the output voltage of the inverter.)