In response to the problem of voltage exceeding limits caused by the large-scale grid connection of distributed energy, a joint dispatch method of "power network-information network" for adjustable load spatiotemporal migration in data centers was proposed. Firstly, an emergency power support strategy was proposed for voltage exceeding limits, which effectively recovers the voltage by adjusting the active power of each node. On this basis, an joint dispatch method considering adjustable load in data center and aggregated power generation from distributed power sources was proposed to meet emergency power support needs with the minimum cost of power regulation. Finally, to meet the real-time and reliable requirements of communication transmission for emergency power dispatch instructions, a communication transmission path dispatch method driven by joint emergency dispatch business requirements was proposed. The results show that this method can recover the voltage exceeding limits within 0.2 s while utilizing communication networks, tapping into the potential of distributed power aggregation and regulation, and adjustable capability of data center loads. The reliability of the method reaches 99.999%, which is of great significance for ensuring safe power supply to the power network under high penetration of distributed energy.