The invention discloses a VSC (Voltage Source Converter) black start device and a black start method based on phase locked loop synchronization control. A solution to frequency establishment and voltage establishment under the condition that a VSC is not integrated into a power grid is provided, and thus, the voltage and frequency of equipment can be independently controlled. Step-by-step start isemployed in the method. Firstly, before start, charging of the direct side of a converter is completed, and the DC voltage is stabilized at the rated value; secondly, a corresponding switch in a control loop is turned off to wait for a black start signal; thirdly, after a black start signal is received, the start process begins, and the frequency and the voltage of equipment are established stepby step according to the signal; and fourthly, after the voltage and the frequency are stabilized, the switch is switched to the original control branch of the equipment according to the black start signal to realize closed-loop control, thus completing the start process. The class synchronization function of a converter based on phase locked synchronization under an isolated power grid is achieved. A feasible and effective solution is provided for the quick self-start of equipment using a VSC as a power grid interface after blackout.