The invention relates to a synchronous reference voltage generation device for improving the precision of trigger pulses. According to the application characteristics of DC transmission, the positive phase sequence digital filtering technology, the voltage synchronous control technology and a step-length-adjustable built-in hardware phase integrator are adopted to achieve real-time accurate measurement of the original side voltage of a converter transformer, a reference waveform synchronous with the voltage strictly is restored in a control system, the original side voltage of the converter transformer is compared with a trigger angle to generate high-precision trigger pulses of a converter valve, and then the purpose of accurately controlling the turn-on moment of the valve is achieved.