35results about How to "Fast response to faults" patented technology

The invention provides a VRRP-based master- and backup- router switching method, and its kernel: when a master router in VRRP (virtual router redundancy protocol) backup group determines to need to make master and backup swithcing, it actively sends a state change request message and reserves the message in the VRRP backup group, and after all routers in the VRRP backup group receive the message, they at once start competing the master router. On the premise of fully assuring service stability, the invention increases switching speed of master and backup routers in the VRRP backup group and effectively shortens failure response time.

A ride-through and recovery method for DC short circuit faults of a hybrid modular multilevel converter based high-voltage direct current transmission (MMC-HVDC) system, the hybrid MMC including multiple full-bridge sub-modules and half-bridge sub-modules, and the method including: 1) detecting whether a DC short circuit fault occurs, and proceeding to step (2) if yes and continuing detecting if no; 2) realizing ride-through of the DC short circuit fault; 3) detecting whether a DC residual voltage increases, and proceeding to step (4) if yes and continuing detecting if no; and 4) realizing DC short circuit fault recovery.

The invention discloses a short trouble current limiter which is composed of a rectifier bridge, a first protective resistor (Rv), a high-temperature superconducting coil (SL), a switching tube (K), a direct current reactor (Lb), a second protective resistor (Ra) and a protected diode (Da), wherein the rectifier bridge is composed of a first diode (D1), a second diode (D2), a third diode (D3) and a fourth diode (D4); a protective resistor (Rs), the switching tube (K) and the high-temperature superconducting coil (SL) are connected in parallel, and the parallel branch is connected between the first direct current end M and the third direct current end P of the rectifier bridge; the second protective resistor (Ra) and the serial branch of the protected diode (Da) are connected with the direct current reactor (Lb) in parallel, and the parallel branch is connected between the second direct current end N and the third direct current end P of the rectifier bridge. The current limiter is connected with the direct current reactor and the high-temperature superconducting coil on the direct current end of the diode rectifier bridge to realize mutual current limiting.

The invention discloses a cascaded grid-connected inverter unit fault detection method based on pulse voltage comparison. The method is applicable to a carrier phase-shifting pulse width modulation (PWM) mode, and comprises three steps of output alternating voltage conditioning and sampling, detection condition judging and fault judging and positioning. An output phase voltage of a cascaded grid-connected inverter is subjected to analog/digital (A/D) sampling through a sensor and a conditioning circuit; when the output phase voltage of the inverter is a direct current side voltage of a single H-bridge unit, the fault can be judged and positioned through simple comparison according to a carrier phase-shifting PWM principle. According to the method, only the output three-phase voltage is required to be sampled and simply compared, so that a direct current side voltage value of the H bridge unit of the cascaded inverter can be rapidly and accurately obtained, the fault is further judged, the fault judgment can be conveniently realized through software, the cost is saved, the efficiency is improved, and the method has high research and application values in aspects of real-time fault detection and direct current side voltage balance control of the cascaded grid-connected inverter.

The invention discloses a saturated bridge type short circuit fault current limiter, which comprises a saturated reactor and a rectifier bridge. The connecting point of a first diode (D1) and a second diode (D2) of the rectifier bridge (Br) is a first alternating current end (A); the connecting point of a third diode (D3) and a fourth diode (D4) of the rectifier bridge (Br) is a second alternating current end (B); the connecting point of the first diode (D1) and the third diode (D3) of the rectifier bridge (Br) is a first direct current end (M); the connecting point of the second diode (D2) and the fourth diode (D4) of the rectifier bridge (Br) is a second direct current end (N); the saturated reactor (L) is connected between the first direct current end (M) and the second direct current end (N); one end of an alternating current power supply (Uac) is connected to the first alternating current end (A); the other end of the alternating current power supply (Uac) is grounded; one end of a circuit breaker (SW) is connected to the second alternating current end (B); the other end of the circuit breaker (SW) is connected with a load (RL) in series and is then grounded. The saturated reactor is realized by a permanent magnet and a direct current coil.

The invention provides a master-slave synergic control method and control system of a DC circuit breaker. The method comprises the steps of switching off a mechanical branch switch and recording faultgeneration time when a fault occurs and a breaking signal is given out from a slave control signal; breaking the mechanical switch when the fault generation time is smaller than a time threshold anda current is detected to be 0; and receiving a master control signal when the fault generation time is not smaller than the time threshold and that the mechanical switch is switched off to reach voltage resistance is detected, and judging whether a main branch switch of the DC circuit breaker is switched off or not according to the received master control signal, wherein the master control signalis a system detection signal, and the slave control signal is a changing signal of a DC voltage value in the DC circuit breaker. With the technical scheme provided by the invention, the system fault is judged by combining the accuracy of the system detection signal and the rapidness of slave control in the DC circuit breaker, rapid response speed and accurate judgment are achieved, and misoperation of the DC circuit breaker can be effectively prevented.

The invention discloses a fault operation method under doubly-fed wind power generator direct power control. By adopting the control method, complicated coordinate transformation and compensation adjustment in vector control are avoided, and the control instruction is simple, direct and easy to implement. When the grid voltage sags, weak-magnetic rotor flux prediction control is adopted, the given value of rotor flux is worked out based on the actual value of stator flux, the dynamic behaviors of a doubly-fed wind power generator rotor-side converter in different switching states are predicted according to a discrete model of voltage of the converter, seven voltage vector prediction results are evaluated through a value function, and finally, a voltage vector minimizing the value function is chosen. By adopting the algorithm, the optimal switching state can be predicted as a switching signal of the converter in each sampling period. The method needs neither synchronous rotating coordinate system conversion nor PI regulator design, and has the advantages of fast dynamic response, simple control instruction, and easy implementation. The operation capacity of a doubly-fed wind power generator in fault is improved.

The invention discloses a method and a device for monitoring the working state of an access channel in a wireless network system. The method comprises the following steps of: counting successfully demodulated data packet numbers in the access channel in real time by taking a preset counting time length as a unit, when the number of continuous counting time lengths of which corresponding data packet numbers are 0 and which comprise a current counting time length is greater than a first preset threshold value and data packet numbers corresponding to a plurality of historical counting time lengths meet the conditions of a second preset threshold value, determining that the working state of the access channel is abnormal. By the method and the device, the working state of the access channel can be timely and automatically judged and further confirmed, so a failure response is quicken and system performance is improved; and failures of the access channel of the system can be discovered without the field inspection of real users and informed to an operator for timely processing, so complaints of the users are reduced and the system maintenance cost of the operator is decreased at the same time.

The invention discloses a power generation and distribution intelligent monitoring system comprising a touch screen, an integrated management device, multiple power generator set control devices, multiple load monitoring instruments, a commercial power monitoring instrument, a power generator set air switch, a load air switch and a commercial power switch. RS485 asynchronous serial communication is performed among the integrated management device and the power generator set control devices, the commercial power monitoring instrument and the load monitoring instrument respectively. The touch screen and the integrated management device are connected by adopting an RJ45 interface. The integrated management device controls the power generator set air switch, the load air switch and a commercial power switch closing-switching brake according to monitoring data. Commercial power, power generation and power utilization situations are monitored in a concentrated way; the number of power generator sets in use and the generated power of each power generator set are automatically controlled in a remote way according to the size of electricity loads; the power generator sets are managed in a remote and parallel connection way so that parallel operation of any combinations of the power generator sets can be realized; and automatic grid connection and seamless switching of the power generator sets and commercial power can be controlled in the remote way.

The invention discloses an operation state monitoring and fault control system for a low-voltage transformer district. The system comprises a plurality of line monitoring units which are used for acquiring the operating parameters of a line end meter box and a branch box, a topology information acquiring unit which is used for obtaining the topological structure information of the low-voltage transformer district, a processing unit which is used for detecting whether a line and equipment in the low-voltage transformer district are failed or not based on the obtained operating parameters and topological structure information and generating a fault repair list when a fault is determined, and a pushing unit which is used for pushing the fault repair prompt information to maintenance personnelbased on the fault repair list. Through the technical solution of the invention, the fine monitoring of the operating state of the low-voltage transformer district is realized, the fault is timely predicted and repaired, the fault response speed is improved, and the power supply quality and power supply reliability of the power distribution transformer district are ensured.

The invention relates to a two-stage photovoltaic grid-connected power generation optimization device, a control system and a method. The device comprises a double-frequency suppression unit which isused for filtering double-frequency components in the voltage of a medium-voltage direct-current bus and the inductive current of a medium-voltage direct-current bus side, and a control unit which isused forfiltering the voltage of the medium-voltage direct-current bus of the double-frequency component and the inductive current of the medium-voltage direct-current bus side of the double-frequencycomponent according to the voltage instruction value of the medium-voltage direct-current bus, the current of the medium-voltage direct-current bus and the inductive current of the medium-voltage direct-current bus side, and determining an input current optimal instruction value of a DC/DC converter connected with a photovoltaic system through a low-voltage direct-current bus. According to the invention, when a low-voltage fault occurs in two-stage photovoltaic grid-connected power generation, the double-frequency fluctuation of the voltage of the medium-voltage direct-current bus can be suppressed, and the electric energy quality of the medium-voltage direct-current bus is improved.

The invention relates to the technical field of digital medical treatment and artificial intelligence, and particularly discloses a disaster recovery method and device based on an active-active system, equipment and a storage medium. The method comprises the following steps: when it is detected that a disaster occurs in a first machine room, acquiring configuration information of the first machine room, matching a preset fault scene according to the configuration information, and acquiring a corresponding directed acyclic execution stream according to the fault scene; obtaining an execution request sent by a client, and generating an execution instruction of each task node according to the directed acyclic execution flow based on the execution request; obtaining a mapping relation between a corresponding task node and an execution server and corresponding execution script information according to the execution instruction; and determining a target execution server according to the mapping relationship, and running the execution script information on the target execution server to switch the first machine room to the second machine room. By means of the mode, the fault response speed can be increased, and the problem of data loss and damage caused by man-made or natural disasters is solved.

The invention provides a data processing method, a device, electronic equipment, a computer program product and a computer readable storage medium. The method comprises the steps of obtaining multiple pieces of target data for a target application; performing fault recognition processing on the multiple pieces of target data to obtain multiple pieces of fault data in the multiple pieces of target data; performing word segmentation processing on each piece of fault data to obtain at least one keyword of each piece of fault data; performing clustering processing based on the keyword on the multiple pieces of fault data to obtain multiple fault data clusters of the target application; and determining a fault label corresponding to each fault data cluster according to the keyword of the fault data of each fault data cluster. Through the application, the order of magnitude of the fault data can be reduced and the accuracy can be improved through the fault label of each cluster, so that the fault response speed is effectively improved.