276results about How to "Protect safe operation" patented technology

The invention discloses an AC/DC fault ride-through and energy dissipation method for wind power flexible direct grid connection. A system is mainly formed by a direct-drive permanent magnet synchronous generator, a full-power frequency converter, a hybrid MMC and a dissipative resistor. An AC and DC are controlled respectively through the hybrid MMC; during direct current faults, the MMC operatesnear a zero direct voltage through a negative input full-bridge sub-module, and DC fault ride-through can be achieved without needing to block MMC. In order to ensure the safety of a converter valveduring the fault, the dissipative resistor is used to absorb energy during the fault so that a wind farm is disconnected with a grid during the fault and still maintains normal operation.

The invention discloses a low voltage ride-through control method of a doubly fed induction aero-generator, which is used when a power network has short circuit faults. The control method is characterized in that a rotor exciting voltage positive-sequence control current and a rotor exciting voltage negative-sequence control signal are respectively formed through limiting a rotor slip frequency current and a rotor (2-s) rated frequency current when the power network has faults, and a generator is utilized for realizing the attenuation of stator flux transient DC components and reducing the rotor side influences of the stator flux transient components, positive-sequence components and negative-sequence components. The control method has the advantages that no hardware protecting device is required to be added; under the condition that the power network has symmetrical and asymmetrical faults, the overcurrent occurrence of the rotor can be effectively restrained, and the safe operations of the generator and a rotor exciting converter are protected; in the process that the power network has the faults, the transient generator impact to the power network and a mechanical system can be effectively reduced; the normal operation of the generator can be fast recovered after the faults are removed, and the timely support to the power network can be realized.

The present invention discloses a transmission line cleaning and bird repellent device. The device comprises an overhead track arranged along a transmission line, a travelling car arranged on the overhead track, a balance mechanism arranged at the bottom of the travelling car, an inspection robot arranged on the travelling car, a control center arranged on the travelling car and connected with the inspection robot, and a cleaning mechanism arranged on the travelling car and configured to clean the transmission line. Through cooperation of the overhead track and the travelling car, the inspection robot can move along the transmission line to monitor bird conditions on the transmission line and a tower, and a nest is cleaned through a nest pickup mechanism, and the transmission line cleaning and bird repellent device cannot have the inclination phenomenon when grabbing the nest through combination of the balance mechanism arranged at the bottom of the travelling car so as to protect the safety operation of the transmission line; and moreover, a natural bird repellent agent is employed to realize that birds cannot perform nesting again at a former address within a period of time.

The invention relates to a centre drive dual-muld disc casting machine, which comprises a chute, casting discs, a quantitative casting system, sprinkling systems, waste anode hoists, lifter and water channel systems, spraying systems, a control cabinet and a hydraulic system; the dual-mold casting discs are fixedly arranged on a concrete foundation; the quantitative casting system is distributed between the dual-mold casting discs; each sprinkling system behind the quantitative casing system is arranged above eight empty molds of each casting disc along the disc rotation direction; each waste anode hoist is arranged at the outer side edge of each casting disc along with each sprinkling system; each lifter and water channel system is arranged at the outer side edge of each casting disc along with each waste anode hoist; and each spraying system is arranged at the outer side edge of each casting disc along with the lifter and water channel system. The centre drive dual-mold disc casting machine can be matched with a rotary metallurgical furnace, a fixed type anode furnace or other melting furnace and is wide in using range, high in automation degree, safe and reliable and strong in casting capability.

A method for measuring DC resistances of transformer windings comprises the following steps of: 1, connecting an AB-phase test wire of a transformer to a degaussing machine, starting the degaussing machine, changing the wire to a BC phase after the AB phase is degaussed, and repeating the above steps till all residual magnetisms in an iron core of the transformer is eliminated; measuring the DC resistance Rac of a low-voltage side winding ac and the DC resistance RAO of a high-voltage side winding AO by using a magnetism optimization method through a DC resistance testing instrument, and repeating the step 1 to eliminate the residual magnetisms in the iron core of the transformer; measuring the DC resistance Rab of a low-voltage winding ab and the DC resistance RBO of a high-voltage side winding BO by using the magnetism optimization method through the DC resistance testing instrument, and repeating the step 1 to eliminate the residual magnetisms in the iron core of the transformer; and measuring the DC resistance Rca of a low-voltage winding ca and the DC resistance RCO of a high-voltage side winding CO by using the magnetism optimization method through the DC resistance testing instrument, and repeating the step 1 to eliminate the residual magnetisms in the iron core of the transformer. According to the method for measuring the DC resistances of the transformer windings, excessive magnetizing inrush current of the transformer no-load closing is avoided and the safety operation of the transformer is protected.

The invention provides an identification method and device for the denial of service attack. The identification method for the denial of service attack comprises the following steps of obtaining the total amount of access requests sent to a target host within a first preset time period, and recording as a first request amount; judging whether the first request mount exceeds a threshold value which is obtained by calculating the page view of the target host; and if so, determining that the target host is subjected to the denial of service attack. According to the technical scheme disclosed by the invention, the total amount of the access requests sent to the target host within the preset time is used as a judgment target, the threshold value is obtained by the page view statistics of the target host to serve as a criteria to judge whether denial of service attack is received, the denial of service attack phenomenon is concluded to identify the denial of service attack so as to bring convenience to take corresponding measures, the identification accuracy of the denial of service attack is greatly improved, and the safety protection of the host is realized.

A bird-repellent device for an insulator of an electric power tower is characterized by comprising a U-shaped ring base, a fastening bolt, a locking gasket, a fastening nut, an anti-bird horn installation groove and anti-bird horns, wherein the U-shaped ring base is clamped on the electric power tower, the fastening bolt penetrates through a threaded hole in the bottom of the U-shaped ring base to abut against the locking gasket, the fastening nut is in match connection with the fastening bolt, the anti-bird horn installation groove is fixedly formed in the upper portion of the U-shaped ring base, and the anti-bird horns are fixedly arranged in the anti-bird horn installation groove. The bird-repellent device for the insulator of the electric power tower has the advantages that by means of the fixing mode of the U-shaped ring base, the protection radius can be enlarged effectively to be higher than 0.7 meter under the premise that a cross arm of the tower is unchanged, the insulator can be covered completely, birds are repelled, and lines can be used safely.

Provided is a turbine-generator shaft system torsional vibration protection method and device. The method includes the steps of collecting shaft system torsional vibration signals, determining the threat situation of the torsional vibration on the safety of units through a fatigue inverse time limit criterion (protection criterion I), a static instability criterion (protection criterion II) and a quick operation criterion (protection criterion III), and performing protection trip and warning to avoid more damage of the torsional vibration to a turbine-generator shaft system. The torsional vibration protection device comprises a speed sensor, a pulse input module (PI), a main control module (CM), a digital input module (DI), an analog input module (AI), a digital output module (DO) and a power supply module (POW). The speed sensor is connected to the pulse input module of the protection device through a cable. The protection device is in communication with a human machine interface (HMI) of a master station through Ethernet.

The invention relates to an electrical locomotive overvoltage suppression absorbing system, which comprises an overvoltage suppression absorbing device and an overvoltage suppression absorbing system control device, wherein the overvoltage suppression absorbing device and electrical locomotive core electric equipment are connected in parallel to a secondary side winding of an electrical locomotive high voltage transformer, and the overvoltage suppression absorbing device is used for suppressing and absorbing overvoltage generated by operation when an electrical locomotive passes a split phase; and the overvoltage suppression absorbing system control device is connected with the overvoltage suppression absorbing device and is used for controlling the action of the overvoltage suppression absorbing device when the electrical locomotive passes the split phase, and cutting off the overvoltage suppression absorbing device after the electrical locomotive passes a split phase area. In addition, the invention also discloses a control method for the electrical locomotive overvoltage suppression absorbing system. The Electrical locomotive overvoltage suppression absorbing system and the control method thereof can better solve the problem of operating overvoltage of the electrical locomotive, protect locomotive equipment and power supply system equipment from the influence of the overvoltage, and further improve the railway transportation safety.

The invention relates to an online monitoring system and an online monitoring method of the deflection of a portal crane girder, which belong to the technical field of deflection monitoring of the portal crane girder. The system comprises a reflecting device, a pulse distance measuring device, a data recording device and a data analyzing and processing device, wherein the reflecting device is installed on a lower cover plate of the portal crane girder, the pulse distance measuring device is installed on a support leg of a portal crane, the output end of the pulse distance measuring device is connected with the input end of the data recording device, and the output end of the data recording device is connected with the input end of the data analyzing and processing device. According to the system, the deflection change of the portal crane girder can be monitored in real time in the process of operation, the whole management level is increased, the safe operation of the crane can be greatly guaranteed, the personal safety of working personnel is protected, and accidents are avoided. Compared with the prior art, the system has the advantages of reasonable design, convenience in use and capability of stable long-term real-time monitoring and detection.

The invention relates to a gas compressor on-line characteristic analysis method based on the temperature control function of a gas turbine. The method is characterized by comprising the following steps: 1) performing rationality analysis on the differential pressure data of the intake manifold of the gas compressor and getting rid of some irrational data; 2) working out the air mass flow of the gas compressor according to the data sample acquired in step 1) and the size of the side section of the intake manifold, measuring and calculating the operating performance of the gas turbine by combining the data communication system (DCS) data, and adopting the operating data with small relative error as the modeling sample; 3) establishing a variable working condition model of the gas compressor comprising 3-1) establishing a temperature control rule model for the inlet guide vane (IGV) of the side section of the intake manifold of the gas compressor of the gas turbine; 3-2) establishing a pressure ratio model of the gas compressor; 3-3) establishing a flow model of the gas compressor; 3-4) establishing an intake resistance model of the gas compressor; and 3-5) establishing a gas compressor efficiency-flux characteristic curve based on the temperature control rule for the IGV of the side section of the intake manifold of the gas compressor. According to the invention, the air mass flow entering the gas compressor is limited through adjusting the blade angle of an adjustable guide vane, so that the purposes of protecting safe operation of the unit and improving the operating efficiency are realized.

The invention relates to a method and device for protecting safe operation of an intelligent device. The method comprises the following steps: monitoring the operational condition of a program on the intelligent device in real time; determining the program which is infected with virus according to the operational condition of the program; and interrupting the operation of the program which is infected with the virus, and replacing the operation with the back-up program which is not infected with the virus. According to the embodiment of the invention, an anti-virus function is realized on the premise of not establishing a virus feature library and not performing virus scanning; and the user operation is simplified, the anti-virus time is saved, the infringement of the intelligent device virus to the intelligent device is also effective prevented, and the safe operation of the intelligent device is protected.

The embodiment of the invention discloses a coal mill starting control method, system and coal mill starting equipment, relates to the field of starting control, and solves the problems caused by the excessive power of the coal mill in the prior art to the power grid and the motor. A technical problem with too much impact. The method in the present invention includes: before starting the coal mill, the coal mill starting equipment obtains the soft start parameters and interlocking signals for starting the coal mill; the coal mill starting equipment configures according to the soft start parameters; After the configuration is completed, the coal mill starting device determines whether the interlock signal meets the soft start condition; when it is determined that the soft start condition is satisfied, the coal mill starting device starts the coal mill according to the configuration. The embodiments of the present invention are mainly used for starting high-power equipment such as coal mills.

The invention discloses an oil purifier for oil used in an anti-explosion boat. The oil purifier for the oil used in the anti-explosion boat is characterized by comprising a bottom plate and an oil inlet portion, a filtering portion, an oil outlet portion and a control portion, wherein the an oil inlet portion, the filtering portion, the oil outlet portion and the control portion are arranged on the bottom plate. The oil inlet portion is provided with an oil pump which is used as oil power, and an oil inlet end of the oil pump is provided with an oil suction filter for primary filtering; and then the filter portion is sequentially provided with a protection filter, a coalescing separator and a fine filter so as to achieve multiple-layer filtering. By adopting the coalescing separator and combining the principle of comprehensive multiple-layer filtering, the oil purifier for the oil used in the anti-explosion boat is capable of achieving high-efficiency dehydration and meeting demands of fine separation and real-time separation, and has the advantages of being small in size, low in energy consumption, little in vibration, long in service life, easy and convenient to operate and maintain, low in operation cost, good in anti-explosion performance, safe and reliable and high in automatic degree.

The invention discloses a fuel gas distributed type energy supply device for cooling inlet air by using solar energy. The fuel gas distributed type energy supply device comprises an air filter (1), a gas turbine generator set (2), a double-pressure residual heat boiler (3) and a steam turbine generator set (4), and further comprises a solar heat collector (5), a heat collection system heat exchanger (6), a hot water storage tank (7) and an absorption type refrigerator (8) which are connected in sequence by a pipeline, wherein the hot water storage tank (7) is connected with the side of a tail heat exchanger of the double-pressure residual heat boiler (3) through a pipeline; and the absorption type refrigerator (8) is connected with the air filter (1). According to the fuel gas distributed type energy supply device, solar heat absorption type refrigeration is used for cooling inlet gas of a gas turbine and the output power and efficiency of the gas turbine are improved, and the fuel cost is saved; meanwhile, combined cycle residual heat of fuel gas and steam is sufficiently utilized and the economy of the system is improved; and the aims of complementary advantages, energy conservation and environmental friendliness of renewable energy sources and a fuel gas distributed type energy supply system can be realized.

The invention relates to the field of equipment manufacturing in the sludge treatment industry and provides an automatic pressure balancing device for a pressure filter. The automatic pressure balancing device comprises a thrust plate, filter plates and a pressing plate, wherein the thrust pate, the filter plates and the pressing plate are arranged in sequence. The pressing plate is connected with a main cylinder. A feeding pump and a water inlet pipe are connected with the filter plates. The automatic pressure balancing device is further provided with a material-oil conversion leather bag, a water-oil conversion leather bag, an oil cylinder and air cylinder assembly and a pressure stabilizing gas storage tank. A small oil cylinder is located on the upper portion of the oil cylinder and gas cylinder assembly, and a large oil cylinder is located on the lower portion of the oil cylinder and gas cylinder assembly. A piston rod of the small oil cylinder is connected with a piston rod of the large oil cylinder. Pre-pressing air cylinders are arranged on the left side and the right side of the large oil cylinder correspondingly. The piston rod of the large oil cylinder is connected with piston rods of the two pre-pressing air cylinders through a cross rod. Four cylinder bodies of the small oil cylinder, the large oil cylinder and the pre-pressing air cylinders are connected through a square frame. The automatic pressure balancing device is further provided with a proximity switch. The large oil cylinder is connected with the material-oil conversion leather bag and the water-oil conversion leather bag. The small oil cylinder is connected with the main cylinder. The pressure stabilizing gas storage tank is connected with the two pre-pressing air cylinders. By the adoption of the automatic pressure balancing device, the dynamic balance between the material pressure or water pressure and the oil pressure of the main cylinder is achieved, the situation that the filter plates are damaged under excessively high pressure is avoided, the structure is simple, and maintenance is convenient.

The invention discloses a double-fed induction generator wind turbine Crowbar resistance design method based on a fuzzy membership function. The double-fed induction generator wind turbine Crowbar resistance design method comprises the following steps: according to an equivalent circuit model of a double-fed induction generator wind turbine in case of a power grid fault, and with the combination of a maximum fault current limiting condition and a direct-current bus capacitor voltage limiting condition, acquiring extreme value constraint relationship equations of rotor current and the Crowbar resistance as well as the direct-current bus voltage and the Crowbar resistance; respectively establishing fuzzy membership functions of the two constraint relationship equations according to the membership degree function concept of the fuzzy control principle; confirming the cross point of the two fuzzy membership functions in one same coordinate axis, thereby obtaining the Crowbar resistance corresponding to the cross point which is taken as the Crowbar resistance confirmed by using the method. By adopting the method, both the influence of over current of a rotor current transformer and the limiting condition of over voltage of direct current procedures of the rotor current transformer are considered, so that the security operation of the rotor current transformer of the double-fed induction generator wind turbine in a fault period is ensured to a maximum extent.

A body holding apparatus of a transformer belongs to the manufacturing technical field of matching accessories of transformers. The body holding apparatus mainly comprises a coil pressure plate (9) and an iron core upper clamping piece (1) installed at the upper part of a coil (10), a washer (8) equipped with a lock block sheath (7) and installed on the coil pressure plate (9), a belleville spring (6) and a lock block (5) installed in the lock block sheath (7), and a compressing screw rod (4) equipped with a screw nut (2) and a connecting piece (3) and installed on the lock block (5). One end of the connecting piece (3) is fixedly welded with the iron core upper clamping piece (1). The body holding apparatus has the advantages of reasonable integral structure design, low cost and simple installment, and can overcome the defects that when the transformer is transported, the coil and the coil pressure plate separate from each other due to the shock caused in turning, sudden braking, bumping and normal and safe running of a transport vehicle, thereby ensuring that the coil pressure plate can stand a sustained pressure and the compactness of the structure of the body, and improving the transformer resistance to short-circuit.