Microgrid operation control is the critical technology for microgrid security and stability. It can be divided into two parts: local-level distributed generation（DG） control and system-level operation control. For the local-level DG control， the paper divides all kinds of DGs into two clusters: master type and power source type. The different control schemes for two DG clusters are proposed. The master type DGs use droop control scheme in the island mode and use PV control scheme in the grid-connected mode， while the power source type DGs use PQ control scheme in both modes. The DG and microgrid interface for plug and play is presented. For the system-level operation control， the paper adopts supervisory operation control system， and presents microgrid grid-connected operation control strategy and seamless control strategy. The testbed for microgrid operation control is designed and developed. The testbed comprises one distributed PV generator， one wind turbine， one Capstone C30 microturbine， a battery energy storage and controllable loads. Currently， the testbed is used to test the DG control schemes and seamless control scheme， and experiment results show that the proposed strategy for microgrid operation control is effective and promising. And these tests also proved that the testbed can perfectly undertake the research and test work of microgrid operation control technology.