53results about How to "Improve operational safety and stability" patented technology

The invention relates to a grid line relay protection method applicable to double line faults. According to the method, when a grid topology structure changes after double line fault tripping occurs on a grid, a grid branch admittance matrix and a grid node incidence matrix do not need to be amended, and then the variable quantity of current flowing through each line after the grid double line fault tripping occurs can be calculated directly, so that the calculation time is short, the protection action speed is high and is higher than of a line backup protection algorithm based on the local amount decision, the line can be reliably locked before a line overload relay protection faulty operation, other faulty lines can be isolated rapidly in a tripping mode, and the operation safety and stability of the grid are improved.

The invention relates to a power transmission line phase-to-phase distance protection section III protection method. The method comprises the steps that a fault phase-to-phase voltage, a fault phase-to-phase current and a fault phase-to-phase negative-sequence current at a power transmission line protective installation position are measured firstly, a phase-to-phase arc voltage at a phase-to-phase short-circuit fault point of the power transmission line is calculated, and then the amplitude of the phase-to-phase arc voltage and a rated voltage amplitude of the power transmission line are utilized to form a power transmission line phase-to-phase short-circuit fault relay protection criterion. According to the power transmission line phase-to-phase distance protection section III protection method, lumped parameters are adopted for modeling, the algorithm principle is simple, programs are implemented easily, the calculation amount is small, and protective action is high in speed. By means of the power transmission line phase-to-phase distance protection section III protection method, the power transmission line phase-to-phase short-circuit fault relay protection criterion is formed by utilizing the amplitude characteristics of the phase-to-phase arc voltage, motion performance is not affected by transition resistance and load current, large-area power outage of a power grid caused by great shift of power grid tidal current due to phase-to-phase distance protection III protection false operations under the condition of overload of the power transmission line is effectively prevented, and operation safety and stability of the power grid are reinforced.

The invention relates to a coal mine ventilation air methane back-heating catalytic oxidation device with a combined type oxidation bed. The coal mine ventilation air methane back-heating catalytic oxidation device with the combined type oxidation bed comprises a ventilation air methane inlet system, a ventilation air methane exhaust system, a back-heating system and a reaction chamber, wherein the ventilation air methane inlet system is communicated with the inlet of the reaction chamber, and the ventilation air methane exhaust system is communicated with the outlet of the reaction chamber; one end of the back-heating system is communicated with a ventilation air methane outlet pipe, and the other end of the back-heating system is communicated with a ventilation air methane inlet pipe; an electric heating wire and the combined type oxidation bed are sequentially arranged in the reaction chamber along an air flow direction. The coal mine ventilation air methane back-heating catalytic oxidation device with the combined type oxidation bed is characterized in that the combined type oxidation bed comprises multiple catalytic oxidation layers which are formed by the filling of honeycomb type catalysts, the catalysts adopted in the catalytic oxidation layers close to the electric heating have high active component loading capacity, large specific surface areas and high cell density, and the active component loading capacity, the specific surface areas and the cell density of the catalysts adopted in the other catalytic oxidation layers are reduced along the airflow direction in a stepped manner. The coal mine ventilation air methane back-heating catalytic oxidation device with the combined type oxidation bed has the advantages of low ignition temperature, high oxidation efficiency, good operation stability and the like.

The invention relates to a technical field of power grid generation control, in particular to provide an intelligent quantization weighted hydroelectric generating set automatic generation control system and arithmetic which comprises four functional modules: an electrical system zone control deviation calculation module, an intelligent quantization weighted automatic generation control module, a hydroelectric generating set subnet unbalancedness optimal operation output allocation module and a parameter self-adjusting optimal computation module. The intelligent quantization weighted hydroelectric generating set automatic generation control system and arithmetic is capable of quickly compensating random wavy load and the disturbance which the power imposes on line frequency and power balance, improving mains supply power quality, increasing the ability that the power grid absorbs wind power to generate electricity and improving the stability of security of operation of the electrical system.

The invention discloses an AC / DC decoupling control method of a modular multi-level converter. The method comprises the steps as follows: DC control is added to current inner loop control and comprises positive DC control and negative DC control, so that an output of AC control, an output of positive DC control and an output of negative DC control are taken as main components of output voltage reference values of various phase bridge arms of an MMC; and control on the main components of the output voltage reference values of various phase bridge arms of the MMC can be achieved by controlling the reference values and the outputs of the AC control, the positive DC control and the negative DC control, thereby preventing the converter from being locked due to overcurrent of the bridge arms in a DC failure. The invention further discloses an application of the method in the flexible DC power transmission system. According to the method disclosed by the invention, the condition that AC and DC are maintained within a safety range can be ensured, so that DC fault ride-through of the overhead flexible DC power transmission system is achieved.

The invention discloses a slow decarbonization-nanofiltration combined softening treatment system and method for the circulating cooling water of a thermal power plant. The system comprises a circulating water cooling tower, a raw water tank, a desulfurizing absorption tower, a nanofiltration system and a slow decarbonization system, wherein the slow decarbonization system comprises a coagulation tank, a flocculation tank, an efficient clarifying tank, a coagulant storage tank, a lime milk storage tank and a coagulant aid storage tank. The system and method disclosed by the invention can be adopted for treating the circulating cooling water while the operation is simple and the cost is relatively low.

The invention discloses a package printing setting management system based on big data. According to the system, various information acquisition modules are arranged in the data acquisition module, so that the system can acquire data of each process in the packaging and printing process, the accuracy supervision in the packaging and printing process is improved, and the operation safety and stability of the system are improved. A data acquisition drive program is arranged in the big data management module, the development workload can be greatly reduced through the platform, user maintenance is facilitated, and data can be normally acquired when new equipment is accessed. Data collected by the Internet of Things platform are stored in databases such as an equipment database, a production database and a log database, so that the production efficiency is improved, and the labor burden of workers is relieved.

The invention provides filtering equipment for water in transformer oil and a use method thereof. The filtering equipment comprises an air compressor, a dryer and a triple filtering device, wherein connecting hoses are arranged among the air compressor, the dryer and the triple filtering device; the triple filtering device comprises a first filtering tank, a second filtering tank and a third filtering tank which are connected in sequence; each of the first filtering tank, the second filtering tank and the third filtering tank comprises an upper cover, a tank wall, a lower cover and super-hydrophobic filter cloth; the super-hydrophobic filter cloth is arranged above the lower cover, and the edge of the super-hydrophobic filter cloth is arranged between the tank wall and the lower cover; and a groove is formed in the middle of one side of the lower cover, an oil outlet hole is formed in the middle of the groove, and the oil outlet hole is provided with an oil outlet switch. The filtering equipment is used for removing trace moisture in the transformer oil without a large amount of energy consumption, and meanwhile, filtering precision can be improved; and moisture in insulating oil is finely filtered, so the operation safety and stability of oil filling equipment are improved.

The invention relates to the technical field of elevator manufacturing, in particular to a traction machine brake. The traction machine brake comprises a brake disc. A left brake pad and a right brake pad are arranged on the two sides of the left surface and the right surface of the brake disc respectively. The side, backing on to the brake disc, of the left brake pad is fixed to an armature plate. The side, backing on to the brake disc, of the right brake pad is fixed to an iron core plate right opposite to the armature plate. A connecting part is fixed to the side, close to the brake disc, of the armature plate and located above the brake disc, a connecting part is fixed to the side, close to the brake disc, of the iron core plate and located above the brake disc, and the two connecting parts can be crossed in the left-and-right direction. The connecting part of the armature plate and the connecting part of the iron core plate form a combined connecting part after being crossed and are connected in series through a connecting shaft rod arranged in the front-and-back direction, and the part, in front of the armature plate and the iron core plate, of the connecting shaft rod and the part, at back of the armature plate and the iron core plate, of the connecting shaft rod are connected to a brake installation base. The part, above the connecting shaft rod, of the iron core plate is provided with an electrified coil and a brake spring used for abutting against the armature plate. The traction machine brake is high in safety and stability, small in loss and low in noise and cost.

The invention provides a secondary air online measuring method for a turbulent burner, and the secondary air online measuring method is used for measuring the air speed in a secondary air duct of theturbulent burner. The measuring method comprises the following steps of selecting three measuring radiuses in the secondary air duct, wherein three circumferences taking the central point of the secondary air duct as the center of a circle by the three measuring radiuses, and the three circumferences are successively an inside circumference, a middle circumference and an outside circumference; anddividing the radial cross section of the secondary air duct into four annular regions by the three circumferences, wherein the radiuses of the three circumferences are successively r1, r2 and r3. Themethod provided by the invention can measure the blast capacities of secondary air hoses truly and effectively, provides a good basis for optimizing air distribution, optimizes the air distribution mode, reduces the electric consumption of a fan, reduces the station service power consumption rate, and improves the economical efficiency of a boiler.

The invention discloses a liquid light hydrocarbon gasification system. The liquid light hydrocarbon gasification system comprises a gasification pipeline, an auxiliary starting pipeline, a detectionpipeline, a jet flow mixing tank, a cyclone spiral tube and a distributor; the upper end of the jet flow mixing tank is provided with a liquid light hydrocarbon inlet and an air inlet; the lower end of the jet flow mixing tank communicates with one end of the cyclone spiral tube, the other end of the cyclone spiral tube communicates with one end of the distributor, and the other end of the distributor is provided with an air outlet; the gasification pipeline is sequentially connected with a first electromagnetic valve and a proportional regulating valve from the inlet end to the outlet end ofthe gasification pipeline; the auxiliary starting pipeline is sequentially connected with a second electromagnetic valve, a manual adjusting valve and a time relay from the inlet end to the outlet endof the auxiliary starting pipeline; and the detection pipeline comprises a safety probe and an oil return pump. According to the liquid light hydrocarbon gasification system, under the action of thejet flow mixing tank, air can be fully contacted and mixed with liquid light hydrocarbon; and gas mixed in the jet flow mixing tank can further promote mixture between the light hydrocarbons and the air and improves the mixing effect through the cyclone flow guiding function of the cyclone spiral tube.

The invention provides a turbulent burner secondary air on-line measuring system. The turbulent burner secondary air on-line measuring system comprises three sets of primary measuring elements which are radially distributed in three circumferences of radial sections of secondary air ducts. The three circumferences use the center points of the secondary air ducts as a center of a circle, and the three circumferences are sequentially the inner circumference, the middle circumference and the outer circumference. The radiuses of the three circumferences are sequentially r1, r2 and r3, and the radiuses are in units of meters. The radius of a first inner wall is rh, and the unit is meter; the radius of a second inner wall is re, and the unit is meter; and r1 is greater than rh, and r3 is less than re. The turbulent burner secondary air on-line measuring system truly and effectively measures the air volume of the secondary air ducts, provides a good foundation for optimizing air distribution,optimizes the air distribution mode to save power consumption of a fan, reduces the power consumption rate of a plant, and improves the economy of a boiler.

The invention provides a rotor structure of a permanent magnet motor, which can balance the axial temperature distribution of the permanent magnets, including a rotor core, a plurality of permanent magnets and eddy current rings; a plurality of permanent magnets and eddy current rings are embedded in the rotor core; The iron core extends axially and is arranged around the axis of the rotor iron core. The section of each permanent magnet is V-shaped; the outer surface of each permanent magnet is fitted with an eddy current ring, and the eddy current ring is located in the axial middle of the permanent magnet. The rotor structure provided by the present invention reduces the eddy current loss where the permanent magnet is wrapped by the eddy current ring by putting the eddy current ring on the axial center of the permanent magnet, thereby balancing the axial temperature distribution of the permanent magnet and reducing thermal stress. Problems with permanent magnet motor failure caused by balance. At the same time, the eddy current ring can reduce the maximum temperature of the permanent magnet, avoid the problem of partial demagnetization of the permanent magnet caused by local high temperature, and improve the safety and stability of the permanent magnet motor.

The invention provides a power coordination control device and method for inertia support and primary frequency modulation of an energy storage power station, a whole station coordination control module is introduced on the basis of a power outer ring and a voltage inner ring of an energy storage converter, and a whole station inertia, primary frequency modulation and dynamic reactive power control unit is arranged in the whole station coordination control module. Therefore, the energy storage power station has millisecond inertia, primary frequency modulation and dynamic voltage regulation response capability. According to the method, the in-station energy storage converter can have the primary frequency modulation characteristic and the inertia response characteristic with higher consistency, the requirements of inertia support and primary frequency modulation of the whole station are met, and the active and reactive power output external characteristics of the energy storage power station are improved; high-precision frequency sampling is achieved, the problem that PCS sampling precision is insufficient is solved, the supporting capacity of an energy storage power station for power grid frequency and stability is improved, and power grid operation safety and stability are improved.

The invention discloses a safety control method and system for suppressing continuous commutation failure of a DC system, including a DC safety and stability control master station, a rectification and commutation control subsystem, and an inverter side state detection subsystem. Based on the commutation failure mechanism, through The number of commutation failures in the DC system and the commutation bus voltage on the inverter side are detected, and the DC power is rapidly reduced, thereby realizing the suppression of continuous DC commutation failures. The present invention can still reduce the risk of continuous commutation failure in the weak AC state of the receiving end power grid, can effectively prevent the continuous commutation failure of the DC system, and improve the safety and stability of the AC-DC hybrid system.

The invention discloses a novel oscillating water column type oxygenation ship based on a turbocharging technology and an oxygenation method thereof.The novel oscillating water column type oxygenation ship comprises a main ship body, a steel frame platform is installed on the main ship body, a U-shaped oscillating water tank is installed on the steel frame platform, and water is injected into the U-shaped oscillating water tank to divide the two sides of the U-shaped oscillating water tank into two air chambers which are not communicated; a one-way air inlet valve and a one-way air outlet valve which are communicated with the air chamber on the side are arranged on the two sides of the U-shaped oscillation water tank respectively, the two sides of the U-shaped oscillation water tank are each provided with a compressor, air inlets of the two compressors are communicated with the one-way air outlet valve on one side of the U-shaped oscillation water tank through pipelines respectively, and air outlets of the two compressors are communicated with pipelines extending to the bottom of the ship respectively. Turbines in the two compressors are respectively connected with an impact turbine at the bottom of the ship through a vertical rotating shaft, the upper portion and the lower portion of each shell are open, and fixed blades are installed on the upper portions and the lower portions of the impact turbines. The oxygenation ship disclosed by the invention is simple in structure, economical in material, low in cost and suitable for being put into production and use; the compressor and the impact turbine are arranged to improve the air outlet oxygenation depth.

The invention discloses a power transmission line grounding distance protection III segment protection method. The method is characterized in that grounding fault phase voltage, grounding fault phase current, grounding fault phase negative sequence current, and zero sequence current of a power transmission line protection installation part can be measured; a grounding arc voltage phase can be calculated by using the phase of the grounding fault phase negative sequence current, and a grounding arc voltage amplitude of a power transmission line grounding fault point can be calculated, and a voltage amplitude variable quantity corresponding to a power transmission line grounding fault front / rear grounding fault point can be calculated, and then the grounding distance protection III segment protection criterion can be formed by using the voltage amplitude variable quantity corresponding the grounding fault point and the power transmission line rated phase voltage amplitude. The power transmission line grounding distance protection III segment protection criterion can be formed by using the grounding arc voltage amplitude characteristic of the power transmission line grounding fault point, and in principle, the influence of the additional impedance caused by the transition resistance on the grounding distance protection III segment protection motion performance can be eliminated, and then the capability of tolerating the strong transition resistance and the strong load current influence can be provided, and therefore the power transmission line grounding distance protection III segment protection correct motion can be guaranteed, the power grid flow big transfer caused by the back-up distance protection motion can be effectively prevented, and the safety and stability of the operation of the power grid can be enhanced.

The invention provides a generator neutral point displacement voltage limiting method, comprising the following steps: after the generator voltage circuit is installed, measure the generator three-phase stator circuit voltage and the current neutral point displacement voltage in real time; The difference between the maximum value and the minimum value among the three-phase stator circuit capacitances determines the capacitance that needs to be supplemented by the three-phase stator circuit; according to the determined supplementary capacitance of the three-phase stator circuit and the above-mentioned capacitance parameter setting requirements, the capacitor type is selected; clear After the capacitor, install the capacitor at the designated position; after the installation, measure the neutral point displacement voltage of the compensated three-phase stator circuit capacitance of the generator in real time to check whether the requirements are met; if the requirements are not met, repeat the above steps until Meet owner or standard requirements. The invention effectively suppresses the neutral point displacement voltage of the generator.

The invention particularly discloses an improved fan oil station electrical control system, which comprises a main loop and a secondary loop, wherein the main loop comprises a primary power supply circuit of an oil station pump; the secondary loop comprises a control loop of the oil station pump and an instrument-controlling instrument control loop; primary power supplies of the oil station pump in the main loop respectively supply power directly; phase-sequence relays are introduced to direct power supply ends of the primary power supplies of the oil station pump; second power supplies in the oil station pump control circuit in the secondary loop are respectively introduced by C-phase power supplies of the first power supply; and a two-position relay and a DCS (Distributed Control System) control point are arranged in the oil station pump control loop of the secondary loop.