Abstract: An integrated electric oil pump and an operation method thereof are disclosed. The integrated oil pump includes a pump housing; an oil inlet; an oil outlet; a fixed shaft in the pump housing; an inner gear eccentrically and rotatably connected with the fixed shaft; an outer gear coaxially connected with the fixed shaft and rotatably arranged in the pump housing, the outer gear is located at an outer periphery of the inner gear and engaged with the inner gear; a motor rotor, the motor rotor is fixedly connected to an outer periphery of the outer gear; and a motor stator at an outer periphery of the rotor, the motor stator is fixedly connected with the pump housing; one end of the channel is in communication with the oil inlet, and an internal circulation of the cooling oil is achieved through the channel.

Abstract: An electric oil pump, including a pump housing, a fixed shaft in the pump housing, an inner gear eccentrically and rotatably connected to the fixed shaft, an outer gear coaxially connected to the fixed shaft and rotatably arranged in the pump housing, the outer gear is located at an outer periphery of the inner gear and engaged with the inner gear, a motor rotor fixedly connected to an outer periphery of the outer gear, and a motor stator at an outer periphery of the motor rotor, the motor stator is fixedly connected to the pump housing. A projection area of the motor stator, a projection area of the motor rotor, a projection area of the outer gear, a projection area of the inner gear and a projection area of the fixed shaft on a plane through an axis of the fixed shaft at least partially overlap.

Abstract: The present disclosure provides a comprehensive utilization method and test equipment for surface water, a goaf and geothermal energy in a coal mining subsidence area. The method comprises the following steps: determining a geothermal water collection area, arranging heat energy exchange equipment in a main roadway, and arranging a geothermal water extraction system, wherein the geothermal water extraction system comprises geothermal wells, extraction pipelines and tail water reinjection pipelines, the extraction pipelines are connected with the heat energy exchange equipment, and the tail water reinjection pipelines are connected with a water outlet of the heat energy exchange equipment; arranging a water channel on the surface, and arranging a drainage system on a subsidence trough to guide surface water to flow underground; and controlling directional and ordered flow of surface water through the coal mining subsidence area formed by ground mining to achieve sustainable mining of underground water.

Abstract: Disclosed is an optimized energy interconnection system for an urban railway train in the technical field of urban railway transportation power supply, for addressing the technical problem that distribution of regenerative braking energy flows cannot be accurately determined. The system includes a DC intermediate bus and a multi-port flow controllable energy router. The multi-port flow controllable energy router can comprehensively control a source and a load connected in parallel on the DC intermediate bus and thus can accurately determine the distribution of regenerative braking energy flows, thereby forming a well-developed system for evaluating usage of the braking energy.

Abstract: The present disclosure provides a comprehensive utilization method and test equipment for surface water, a goaf and geothermal energy in a coal mining subsidence area. The method comprises the following steps: determining a geothermal water collection area, arranging heat energy exchange equipment in a main roadway, and arranging a geothermal water extraction system, wherein the geothermal water extraction system comprises geothermal wells, extraction pipelines and tail water reinjection pipelines, the extraction pipelines are connected with the heat energy exchange equipment, and the tail water reinjection pipelines are connected with a water outlet of the heat energy exchange equipment; arranging a water channel on the surface, and arranging a drainage system on a subsidence trough to guide surface water to flow underground; and controlling directional and ordered flow of surface water through the coal mining subsidence area formed by ground mining to achieve sustainable mining of underground water.

Abstract: Disclosed is an optimized energy interconnection system for an urban railway train in the technical field of urban railway transportation power supply, for addressing the technical problem that distribution of regenerative braking energy flows cannot be accurately determined. The system includes a DC intermediate bus and a multi-port flow controllable energy router. The multi-port flow controllable energy router can comprehensively control a source and a load connected in parallel on the DC intermediate bus and thus can accurately determine the distribution of regenerative braking energy flows, thereby forming a well-developed system for evaluating usage of the braking energy.