Abstract: A method for checking a medium-term and long-term maintenance plan of a power grid. A predicted load value and one or more historical load values of a power grid are acquired and clustered through a clustering algorithm, and a historical moment at which a historical load value is in a same cluster as the predicted load value and has a largest load value is selected as a target historical moment. A power grid operation mode model at the target historical moment is acquired, and the power grid operation mode model is updated according to the maintenance plan and open loop point information by using a full wiring approach to obtain a future-state power grid operation mode model. Ground state power flow data of the power grid are calculated based on the operation mode model, and safety check is carried out according to a preset ground state power flow limit.

Abstract: A device and method for evaluating long-term operation of a transformer oil pump. An inlet of an oil pump is connected to an outlet of an oil tank through an oil pipe, and an outlet of the oil pump is connected to an inlet of the oil tank through an oil pipe. A pressure gauge is provided on the oil pipe to the inlet and the outlet of the oil pump, respectively. An ultra-high-frequency (UHF) sensor is provided on an inner wall of an oil pipe close to the oil pump. A pressure difference between the oil pipes to the inlet and to the outlet of the oil pump is monitored. A three-phase unbalanced current of a stator winding is monitored. The vibration of the oil pump is monitored. The rotor-to-stator rub is monitored. Based on the above inspection, a long-term health status of the oil pump is determined.

Abstract: Provided in the present disclosure are an IGBT device backside structure and a preparation method therefor, and an IGBT device, the IGBT device backside structure comprising a buffer layer, the buffer layer comprising a first activation efficiency buffer area corresponding to an active area of the IGBT device and a second activation efficiency buffer area corresponding to a terminal area of the IGBT device, the activation efficiency of the first activation efficiency buffer area being less than the activation efficiency of the second activation efficiency buffer area.

Abstract: A device and method for evaluating long-term operation of a transformer oil pump. An inlet of an oil pump is connected to an outlet of an oil tank through an oil pipe, and an outlet of the oil pump is connected to an inlet of the oil tank through an oil pipe. A pressure gauge is provided on the oil pipe to the inlet and the outlet of the oil pump, respectively. An ultra-high-frequency (UHF) sensor is provided on an inner wall of an oil pipe close to the oil pump. A pressure difference between the oil pipes to the inlet and to the outlet of the oil pump is monitored. A three-phase unbalanced current of a stator winding is monitored. The vibration of the oil pump is monitored. The rotor-to-stator rub is monitored. Based on the above inspection, a long-term health status of the oil pump is determined.

Abstract: An evaporative condenser radiating module for steam exhaust of a steam turbine comprises tube bundles and steam-water separating chambers. A steam-water separating chamber (4) between a section A and a section B, a section A downflow cooling section tube bundle (3), a section B downflow cooling section tube bundle (5), and a counter flow cooling section tube bundle (8) are disposes at the left side of a central steam-water separating chamber (7). An upper sealed space (10) of the steam-water separating chamber (4) between the section A and the section B is in communication with the central steam-water separating chamber (7) through the counter flow cooling section tube bundle (8). A lower sealed space of the steam-water separating chamber (4) between the section A and the section B is in communication with the central steam-water separating chamber (7) through the section B downflow cooling section tube bundle (5).

Abstract: An automatic monitoring and alarming device based on large strain of a power transmission tower comprises a solar cell (7), a wireless alarm sending device (6), an insulation basement (5) and a truss with great probability of generating large strain on the power transmission tower. One end of two invar alloy fine rods is respectively fixed on the insulation basement (5). The first invar alloy fine rod (1A) is fixedly adhered to the truss with great probability of generating large strain on the power transmission tower, and the arrangement direction of which is the same as the strain generating direction of the truss. The second invar alloy fine rod (1B) is sleeved with an insulation bushing (4) and is suspended on the outside of the truss with great probability of generating large strain. The solar cell (7), the wireless alarm sending device (6), a metal probe (2) and a metal contact (3) together form an alarm circuit.

Abstract: Disclosed is a method for determining the spatial location of a conducting wire and an aerial earth wire of a power transmission line, so as to solve the problem that the method in the prior art is not applicable to determining the spatial location of the conducting wire and the aerial earth wire of the conventional power transmission line with respect to lightning shielding failures.

Abstract: A main stream temperature control system for a large boiler comprises a PID module, A/D converters (M2, M3, M4, and M5), D/A converters (M6 and M7), electrical water spray adjusting valves (AA101 and AA102) and main stream temperature sensors (T1, T2, T3, and T4) for the boiler. The system uses a function module (f (x)), a differential module, a division module, multiplication modules (F1 and F2), addition and subtraction modules (J1, J2, J3, and J4), set value modules (K1-K6), selection modules (N1 and N2), a time pulse module (S1) and small value comparison modules (Z1 and Z2) in a distributed control system, so as to construct a real-time online optimized circuit and form an independent automatic control system for dynamic tracking and stable control, thereby increasing the thermal economic index of the boiler, and achieving the objective of energy saving and emission reduction.

Abstract: An evaporative condenser radiating module for steam exhaust of a steam turbine comprises tube bundles and steam-water separating chambers. A steam-water separating chamber (4) between a section A and a section B, a section A downflow cooling section tube bundle (3), a section B downflow cooling section tube bundle (5), and a section C counter flow cooling section tube bundle (8) are disposes at the left side of a central steam-water separating chamber (7). An upper sealed space (10) of the steam-water separating chamber (4) between the section A and the section B is in communication with the central steam-water separating chamber (7) through the section C counter flow cooling section tube bundle (8). A lower sealed space of the steam-water separating chamber (4) between the section A and the section B is in communication with the central steam-water separating chamber (7) through the section B downflow cooling section tube bundle (5).

Abstract: An automatic monitoring and alarming device based on large strain of a power transmission tower comprises a solar cell (7), a wireless alarm sending device (6), an insulation basement (5) and a truss with great probability of generating large strain on the power transmission tower. One end of two invar alloy fine rods is respectively fixed on the insulation basement (5). The first invar alloy fine rod (1A) is fixedly adhered to the truss with great probability of generating large strain on the power transmission tower, and the arrangement direction of which is the same as the strain generating direction of the truss. The second invar alloy fine rod (1B) is sleeved with an insulation bushing (4) and is suspended on the outside of the truss with great probability of generating large strain. The solar cell (7), the wireless alarm sending device (6), a metal probe (2) and a metal contact (3) together form an alarm circuit.