39results about How to "Reduce the scope of failure" patented technology

The invention relates to a low-expense high-survivability PON protection structure, and belongs to the technical field of optical networks. A plurality of different functional units of logic decision, backup transmitting-receiving, protection path control, and the like are additionally arranged in an optical line terminal; the switching of an optical switch is confirmed by the logic decision unit according to received logic signals; protection wavelength of a faulty component is tuned by the backup transmit-receive unit to enable a WDM part to conduct switching operation just on the faulty component to realize low expense concentrated protection; a cross concentration line structure is adopted at a TDM part; quick distributed protection switching is realized when ONU detects fault. According to the invention, the number of components participating in the protection switching in the WDM / TDM-PON system is effectively decreased; influence range of the fault is reduced; protection resource expense on the fault is reduced; full protection to all optical fiber fault in the whole system is realized.

The present application discloses a DC short-circuit fault ride-through control method and related devices, including breaking the DC circuit breaker on the island side in the faulty pole to remove the fault; The transmitted active power determines the type of power transfer condition; if the type of power transfer condition is self-consumption condition, control the island-side converter station in the non-faulty pole to increase the output power to pass the non-faulty pole after the fault is removed. The middle-island-side converter station transfers all the active power of the island-side converter station in the faulty pole; if the power transfer condition type is non-self-consumption condition, control the non-faulty-pole middle-island-side converter station to run at full power and control the wind farm to increase the load, so as to pass all the active power of the converter station on the island side in the non-faulty pole and the converter station on the island side in the fault pole of the wind farm after the fault is removed. This method can effectively reduce the fault influence range and maintain the power balance of the islanded system.

The invention provides a cascade system and method for realizing an automatic circuit bridge connection. The cascade system comprises a central controller and multiple cascaded functional sub-units, wherein each functional sub-unit comprises: a micro-control module, for transmitting bridge control information to a drive module, when the heartbeat detection result of the environment monitoring plate of the current level functional sub-unit is abnormal, after the cascade system powers on; a drive module, for generating a bridge drive signal according to the received bridge connection control information transmitted by the micro-control module; a circuit switching module, for bridge-connecting, according to the bridge connection control signal transmitted by the drive module, the functional sub-unit of the lower level to the functional sub-unit of the upper level or the central controller via a transmission wire, which realizes the automatic bridge connection of the circuit. In the present invention, by using the circuit switching module to bridge-connect the functional sub-unit of the lower level to the central controller or the functional sub-unit of the upper level when the functional sub-unit of the current level has a fault, the effect range of the fault is reduced and the operation reliability of the system is improved.

The invention discloses a precision agronomic control system and method for automatic fertilization and water supply using distributed control. The system includes a plurality of field subsystems, irrigation execution subsystems, and upper monitoring subsystems; each field subsystem communicates with the irrigation execution subsystem through a communication bus. The subsystems are connected to send irrigation requirements to the irrigation execution subsystem; the field subsystem is connected to the upper monitoring subsystem through the communication bus to transmit the working status of the field subsystem; the field subsystem is mainly composed of the field control computer and the temperature sensor connected to it, shallow Layer soil moisture sensors, deep soil moisture sensors, ion concentration sensors, and weather stations; the irrigation execution subsystem is mainly composed of irrigation control computers and connected water pumps, filtering equipment, fertilizer dispensers, and flow monitoring equipment; connected to a field irrigation After the irrigation demand issued by the subsystem, quantitative watering or fertilization is carried out according to the demand. The invention has higher flexibility, higher operation reliability and higher work efficiency.

The present invention relates to the technical field of power systems, and discloses a line selection method, device and storage medium for AC-DC line collision faults. Two current components; the voltage component is the 50Hz component of the voltage of the busbar, the first current component is the 50Hz component of the DC line current flowing into the busbar, and the second current component is the 50Hz component of the DC line current flowing out of the busbar; when the voltage When the component, the first current component and the second current component meet the preset safety conditions, calculate the first power direction and the second power direction of the busbar according to the voltage component, the first current component and the second current component; The first power direction and the second power direction determine the DC line where the AC-DC line collision fault occurs. The invention can realize accurate fault line selection, reduces power loss, and narrows the scope of fault influence.

The invention discloses a double-bond polymer quantum dot film and a preparation method thereof. The prepared ABA three-layer quantum dot primary base film with a thickness of 10-200 μm and B layer with a thickness of 18-300 μm is prepared, and then processed by fluorination technology on both surfaces of the quantum dot primary base film. Double-bond polymer quantum dots prepared by obtaining a quantum dot secondary base film with an ABA three-layer film structure, and then coating a thermosetting resin on both surfaces of the quantum dot secondary base film and forming a coating with a drying thickness of 1-10 μm Membrane; the water vapor transmission rate of the membrane is 0.01~0.1g / m 2 ·24 hours, 1000 hours at 85℃, 85% humidity or 60℃, 90% humidity, the edge failure is 0~0.2mm, used in various display fields, can increase the luminous effect, and make the color more colorful.

A short-circuit test method for a medium-voltage bus of an EMU, which is characterized in that it includes the following steps: 1) The train is provided with multiple auxiliary converters, each auxiliary converter is connected in parallel for output, and N coupling switches are set on the medium-voltage bus, and the normal operation is In the closed state, ensure that the medium-voltage bus runs through all columns; 2) Once a short-circuit fault occurs in the vehicle, first confirm whether it is an internal fault in the auxiliary converter to reduce the scope of the fault; 3) If there is no short-circuit fault in the auxiliary converter, the vehicle will Start the external short-circuit test program, open N coupling switches, divide the medium-voltage bus into N+1 sections, and then put in the auxiliary converters to judge the faulty bus section; 4) After confirming the faulty bus section, open the adjacent 1 or 2 coupling switches, and the non-adjacent coupling switches are closed to ensure the normal operation of medium voltage loads in the bus section without short circuit. The invention can refine the short-circuit fault point, reduce the range of fault influence, even avoid the fault influence, and maintain the operation of the vehicle to the greatest extent.

The embodiment of the present invention discloses a bus tie protection method with an outgoing line reactor. By setting low-voltage blocking and quick-break protection on the bus tie and section circuit breakers, it can be used in the section protection of the bus tie section with an outgoing line reactor. Realize the distinction between internal and external faults of the bus, and combine with conventional current protection to realize the rapidity of bus tie protection, which can quickly remove faults, thereby reducing the scope of fault influence. The bus-tie protection method with outgoing line reactor of the present invention includes: setting a bus-tie circuit breaker and / or a section circuit breaker on the system, and setting a low-voltage lockout on the bus-tie circuit breaker and / or the section circuit breaker Quick break protection and current protection; obtain the current value of the bus tie circuit breaker and the voltage value of the bus where the bus tie circuit breaker is located; compare the current value with the bus tie current setting value, and the voltage value with the bus tie voltage setting value, Obtain a bus tie comparison result; enable bus tie protection according to the protection action logic of the bus tie circuit breaker and the bus tie comparison result.

The present invention provides a protection method and system for partitioning a DC power grid. The protection method includes the steps: the protection method includes the steps: a DC protection unit RPU installed on the tie line of the DC power grid collects fault protection information of a fault isolation device, And judge whether to start its own protection action according to the fault protection information to realize partition fault isolation between DC grids; the local measurement and protection unit LMPU located in the DC grid partition judges whether to start its own protection action based on the fault protection information to realize Fault isolation between the DC grid and the AC grid. The present invention adopts a layered and partitioned DC power grid fault protection framework, each LMPU system is independent of each other, and the coupling relationship between each LMPU and between the LMPU and the upper RPU is less.