122results about How to "Guarantee power supply reliability" patented technology

The invention discloses a ground fault current compensation system and method for a self-produced power supply phase power supply. The system comprises a phase power supply generator, a phase power supply phase compensator, a fling-cut switch, a controller and a voltage transformation device. An output end of a phase compensator of a power supply is connected to a system neutral point through thefling-cut switch. The system can passively generate power distribution network power supply phase power supply and harmonic phase power supply and input anti-phase power supply phase power supply andthe harmonic phase power supply into the system according to fault logic. The complete compensation of power distribution network grounding fault reactive current, harmonic current and active currentis achieved, the defect that compensation is incomplete by adopting a power electronic device inversion injection method after electricity is taken from a bus system is overcome, and the problems thatan active inversion method has a poor metallic grounding compensation effect and a traditional arc suppression coil cannot achieve full compensation are solved. The system is efficient and accurate and can completely compensate overvoltage and overcurrent generated by a grounding fault, the safety of a power grid and equipment is guaranteed, and the risk of electric shock of a human body is completely avoided.

The invention discloses a grounding fault current compensation system and method for a self-generated power supply phase power supply. The grounding fault current compensation system comprises a phasepower supply converter, a fling-cut switch, a voltage transformation device and a controller, wherein the input end of the phase power supply converter is connected with a bus, the output end of thephase power supply converter is connected with the input end of the fling-cut switch, the voltage transformation device is connected between the phase power supply converter and a system neutral pointin series, the controller is connected with a voltage transformer of the bus, and the output end of the controller is connected with the input end of the fling-cut switch. The system can passively generate a power distribution network power supply phase power supply and a harmonic phase power supply, and the reversed-phase power supply phase power supply and the harmonic phase power supply are put into the system according to fault logic, so that complete compensation of reactive current and harmonic current of the grounding fault of the power distribution network is achieved, the defect thatthe compensation is incomplete by adopting a power electronic device inversion injection method after electricity is taken from a bus system is overcome, and the problems that an active inversion method is poor in metallic grounding compensation effect and a traditional arc suppression coil cannot achieve full compensation are solved.

The invention provides a single-tube IGBT (Insulated Gate Bipolar Translator)-based three-stage brushless generator power control device and a power control method. The single-tube IGBT-based three-stage brushless generator power control device comprises a minimum system, a control circuit, a power unit, a power module, an auxiliary exciter, a main exciter, a generator, a first voltage measurement transformer, a second voltage measurement transformer, a third voltage measurement transformer, a first current transformer, a second current transformer, a Hall voltage sensor, a Hall current sensor, a given voltage circuit, an excitation relay, a deexcitation relay, an IGBT drive circuit, an analog input circuit, a phase-locked loop frequency doubling circuit, a discrete input photoelectric isolation module and a discrete output photoelectric isolation module. Because the single-tube IGBT is adopted as a power switching device, switching loss can be effectively reduced, the response speed can be effectively increased, and the reliability is high; a controller is adopted as a main control unit to accurately control the three-stage synchronous generator; because the single-tube IGBT-based three-stage brushless generator power control device can communicates with an upper computer to monitor the system, faults can be rapidly and conveniently diagnosed and overhauled.

The invention provides a greedy algorithm-based scheduling policy for the three-phase load balance of a real-time-allocating distribution network and relates to a scheduling policy for the three-phase load balance of the real-time-allocating distribution network. The scheduling policy comprises the steps of (1) establishing an array Z with the length thereof to be equal to the number of slave switching devices in the distribution network; (2) conducting the real-time online detection on the total currents of three phases Ia_ph, Ib_ph and Ic_ph, and the currents of all users loads of the slave switching devices; (3) determining the value of epsilon; (4) sorting user loads respectively accessed to three phases of A, B and C in the monotonically increasing manner, and respectively storing in linked lists a, b and c; and so on. Compared with the conventional algorithm, a corresponding scheduling scheme can be found out more quickly based on the greedy algorithm. Meanwhile, a plurality of slaves can be simultaneously controlled in the online manner, so that the three-phase unbalance degree of the distribution network is quickly decreased within a short period of time. Therefore, the time-varying characteristics of the electrical loads of the distribution network can be treated.

The invention discloses a power supply method for a grid-connected and off-grid dual-purpose wind and light complement power generation system. The grid-connected and off-grid dual-purpose wind and light complement power generation system comprises a photovoltaic module, a fan, a wind and light complement controller, an inverter, a storage battery, a load and an unloading box, wherein the wind and light complement controller is used for converting power energy acquired by the photovoltaic module and the fan into direct current which is connected into a direct current bus; the storage battery is connected onto the direct current bus; and the inverter is connected onto the direct current bus and is used for converting the acquired direct current into alternating current. An operation method of the system is adjusted according to the state of a main network and the electricity quantity of the storage battery. According to the power supply method for the grid-connected and off-grid dual-purpose wind and light complement power generation system, which is provided by the invention, the problems that no power is supplied to rural users, the reliability of power supply is poor and the like are solved; clean renewable energy sources are fully utilized and the waste of the clean renewable energy sources is avoided; and the loss of the service life of the system is reduced while the power supply reliability of a user is ensured and the service life of the system is prolonged.

A multilevel hierarchical control method of transmission congestion management based on a multi-source active distribution network includes the steps of acquisition of operating data, active reconstruction operation, active islanding operation, demand response operation and the like. The method has the advantages that controllable resources in the multi-source active distribution network can be fully utilized, topological optimization and active isolating operation of the multi-source active distribution network is dynamically achieved, the power demand of the load end of an upstream transmission line can be effectively lowered, a brand-new idea is provided for the congestion control and management of the transmission line, auxiliary services can be provided for the transmission network congestion management at the premise of ensuring operational safety and stability of the distribution network, transmission line congestion can be partly relieved in emergency situations, power supply reliability of the distribution network can be guaranteed as far as possible, and the network has certain engineering application prospect.

The invention relates to a transformer station equipment cloud maintenance system and a monitoring system. The cloud maintenance system comprises a transformer station monitoring subsystem and a remote maintenance subsystem, wherein the transformer station monitoring subsystem comprises a monitoring layer and an evaluation layer, the monitoring layer is used for monitoring the relevant state information of transformer station equipment and outputting the state information to a server of the evaluation layer to acquire health status data of the transformer station equipment, and the remote maintenance subsystem comprises a cloud maintenance work station in remote communication connection with the evaluation server through the network and is used for receiving the health status data of the transformer station equipment sent by the evaluation server. The system is stored with all the operation state information of the whole far-end transmission transformer station, the health status data of the transformer station equipment is acquired through far-end transmission, the data is not scattered data, data bulk is relatively small, so loss of the data does not easily occur, and the cloud maintenance work station further does not misjudge the operation state of the transformer station.

The invention provides a parallel online automatic commutation device of a low-voltage load. The commutation device comprises a control circuit, an input module, a commutation switch module and an output module; and the control circuit receives a commutation phase sequence state instruction sent by a distribution and transformation terminal, calculates an operation instruction of the commutation switch module, and realizes online commutation of the low-voltage load. The invention also provides an operation method of the device. The operation method comprises that 1) the three-phase voltage of power grid, a current of the low-voltage load and a phase sequence state when the low-voltage load is connected to the power grid are collected; 2) the commutation phase sequence state instruction is calculated; and 3) the operation instruction of the device is calculated, and online commutation of the low-voltage load is realized. Compared with the prior art, the device and operation method thereof use an intelligent optimized algorithm to optimize and select the phase sequence state combination of the low-voltage load in a power distribution district, and change the low-voltage load randomly among phases A, B and C, and three-phase loads in the power distribution district are balanced.

The invention provides a distribution network maintenance scheme optimization method and a distribution network maintenance scheme optimization device based on an element failure model. The method comprises the steps of establishing a transformer aging failure model, an overhead line aging failure model, a transformer random failure model and an overhead line random failure model; obtaining a transformer element failure model according to the transformer aging failure model and the transformer random failure model; obtaining an overhead line element failure model according to the overhead line aging failure model and the overhead line random failure model; establishing a distribution network maintenance optimization model according to the transformer element failure model and the overhead line element failure model on the basis of distribution network system constraints and maintenance resource constraints by using the minimum failure risk of a distribution network system as an object; solving a distribution network through a genetic algorithm on the basis of the distribution network maintenance optimization model, so as to obtain an optimal distribution network maintenance scheme.

The invention discloses a power supply seamless switching device and method of an electrified railway traction substation. Four paths of voltages, namely two-phase voltages of buses a and b of a contact network and voltages of a bus I and a bus II of a power supply, and four switching position signals, namely switches 201A and 201B of a low-voltage side of a main transformer 1B and switches 202A and 202B of a low-voltage side of a main transformer 2B are accessed to the switching device. During application, the current running mode of the traction substation is identified according to access quantity, automatic charging is achieved to prepare for switching if the running mode is normal, and discharging is performed to lock a switching function if the running mode is abnormal; three switching modes of parallel automatic switching, parallel semi-automatic switching and series switching can be performed; an optimal switching-on mode can be selected according to a real-time relation between the bus voltages of the power supply and the bus voltages of the contact network during switching on; and six modes of parallel rapid switching, rapid switching, same-phase lead phase angle switching, same-phase lead time switching, residual voltage switching and long delay switching can be performed, and uninterruptible power supply switching of two power supplies of the electrified railway traction substation can be achieved.

The invention provides a double parallel active power filtering apparatus which comprises a DSP, a power supply, a voltage current sampling module, a serial port communication module, an IGBT gate pole drive circuit, a high frequency APF circuit and a low frequency APF circuit. An input terminal of the voltage current sampling module is connected to an electrical network, and an output terminal of the voltage current sampling module is connected to a DSP pin. An output of the DSP is connected to a pin of the IGBT gate pole drive circuit. An output of the IGBT gate pole drive circuit is connected to an IGBT of the high frequency APF circuit and the low frequency APF circuit respectively. The high frequency APF circuit and the low frequency APF circuit are connected to the electrical network back. The power supply and the serial port communication module are externally connected to a DSP port. A voltage transformer is in parallel connection with a current transformer to acquire a signal, a high frequency circuit is parallel connection with a low frequency circuit and the signal is returned to the electrical network, the DSP is taken as a processing unit, a harmonic wave is effectively filtered, and electrical network current is accurately tracked. A soft switch drives the IGBT gate pole drive circuit, zero voltage zero current connection and disconnection of the IGBT are realized, resonance loss is reduced effectively, and precision is raised.

The invention discloses a grounding fault current compensation system and method for a self-produced power supply phase power supply. The system comprises a phase supply power converter, an on-off switch, a voltage regulator and a controller. The input end of the phase power supply converter is connected with a bus, and the output end is connected with the input end of the on-off switch. The common connection point of the on-off switch and the system neutral point are connected on the non-homonymous ends on the two sides of the voltage regulator, and the remaining connection points of the voltage regulator are grounded. The controller is connected with the voltage transformer of the bus. The output end of the controller is connected with the input end of the on-off switch and the voltage regulator. The system can passively generate the power supply phase power supply and the harmonic phase power supply of a distribution network and put the reverse phase power supply and the harmonic phase power supply into the system according to the fault logic so as to realize complete compensation of reactive current, harmonic current and active current of the distribution network grounding fault and solve the problems of poor metal grounding compensation effect of the active inverter method and inability of complete compensation of the traditional arc suppression coil.

The invention relates to the field of voltage data measurement methods, and provides a voltage monitoring and management system data deepening analysis method comprising the following steps that the corresponding index analysis diagram of the voltage detection data and the data list are displayed according to the type of the voltage monitoring point and the voltage grade; different types of voltage monitoring data are acquired and displayed; the unqualified voltage data discovered in acquisition are marked and listed to the abnormal data series; and the qualified voltage rate is calculated according to the specific value of the qualified voltage data to the total voltage data. According to the method, inquiring and statistics of the voltage situation of different voltage grades and different regions can be realized and the line or the transformer area of which the qualified voltage rate is not up to the standard is alarmed. According to the method, inquiring and statistics of the situation of different voltage grades and different regions can be realized and the measuring points of which the qualified voltage rate is not up to the standard are alarmed so that the voltage situationof all the lines and the transformers areas of the power grid can be comprehensively monitored.

The invention discloses a small current grounding comprehensive wire selection method based on electric quantity and non-electric quantity. The method includes the following steps: if a bus voltage abnormal alert is started, acquiring a zero-sequence current of a voltage abnormal bus associated line, determining whether it is established that a certain line has the largest zero-sequence current and the largest zero-sequence current is the sum of zero-sequence currents of the other lines, and if it is established, the line has a grounding breakdown; and if it is not established, acquiring the non-electric quantity information of the voltage abnormal bus associated line, using the method of weighting to compute breakdown probability of each line, successively cutting and removing corresponding lines according to the sequence of the breakdown probability, if the bus voltage returns to normal, then determining that the line has a grounding breakdown. The method can schedule a main station end and accurately identify lines with grounding breakdowns, enables closed-loop processing through remote controlling in a fast and efficient manner, increases the accuracy of small current grounding and switching off, shortens time for processing breakdowns, reduces the work load of scheduling workers, and effectively ensures reliability of grid power supply.

The invention provides a portable cable flaw detection robot system. The portable cable flaw detection robot system comprises a high-definition anti-shake camera, a raspberry part, an LED light, a steering gear cloud platform, a follow camera, an infrared thermal imaging camera, an ultrasonic sensor, a main control panel, a motor drive panel, a power supply, a motor, a trolley body, a support platform, a GPS module and a journey calculation module. the portable cable flaw detection robot system provided by the invention has the following beneficial effects that the portable cable flaw detection robot system has the characteristics of convenience and flexibility, can replace manual inspection, meets the requirements of a large number of daily cable inspection work for substation cable trenches, improves the work efficiency, saves a lot of manpower and material resources, lowers the operating cost, simultaneously greatly guarantees the reliability of the power supply of the substation, and provides a good foundation for big data analysis of the later cable operation management of the substation.

The invention provides a remote detection method and system for a switch cabinet in a distribution network. The method includes the following steps: the environmental information of a switch cabinet in a distribution network is acquired in real time; the environmental information is transmitted to a remote server in real time; the remote server processes the environmental information in real timeand generates display information; and the remote server analyzes and displays the display information. By using the remote detection method and system for a switch cabinet in a distribution network provided by the invention, the temperature, humidity and sulfur hexafluoride gas concentration in a switch cabinet can be monitored, so as to prevent equipment failure and ensure the safe operation ofequipment and the reliability of power supply.

The invention discloses a ground fault current compensation system and method for a self-produced phase power supply, The ground fault current compensation system includes a phase power supply generator, a phase power supply phase compensator, a switch, a controller, and a voltage regulator. The input end of the phase power supply generator is connected to a bus. The output end of the phase powersupply generator is connected to the input end of the phase power supply phase compensator. The voltage regulator is connected in series between the phase power supply phase compensator and the neutral point of the system. The controller is connected to the voltage transformer of the bus. The output end of the controller is connected to the switch. The system passively generates the phase power supply, and puts the inverted power supply phase and the harmonic phase power supply into the system according to the fault logic. The ground fault current compensation system achieves the complete compensation of the reactive current, the harmonic current and the active current of the ground fault of a distribution network, and solves the problems that the power electronic device inversion injection method cannot achieve full compensation and is complex to control after taking power from the system.

The invention belongs to ancillary fittings of current supply equipment, in particular to a plug-in type exhaust fan for a switchgear. The exhaust fan mainly comprises an external fixed frame, a fan and an internal fixed frame, wherein the inside of the external fixed frame is provided with a guide rail; the fan is fixed in the internal fixed frame; the external side of the internal fixed frame is provided with a cam block matched with the guide rail; a power lead of a drive motor of the fan is connected with a power plug. According to the invention, the installation mode of the exhaust fan of the switchgear is reconsidered, the power plug of the exhaust fan is provided, the installation mode that the guide rail is demountable is adopted, the purpose of replacing the exhaust fan quickly on the premise that the operation of the switchgear is not influenced is realized, and the safe operation and the reliable power supply of the switchgear can be effectively guaranteed.

The invention relates to the field of power intelligent energy systems and discloses an intelligent energy system based on a power electronic transformer, which comprises a power electronic transformer, an AC/DC converter, an AC/AC converter, a DC/AC converter, a DC/DC converter, a photovoltaic and the like distributed power supply, an electric automobile, an energy storage system, a DC load, an AC load and various AC generators. According to the intelligent energy system based on the power electronic transformer disclosed in the invention, the power electronic transformer module is formed bythe AC/DC converter, a two-way DC/DC converter and the AC/DC converter, the power electronic transformer can thus be used for switching among four states of DC low voltage, AC low voltage, DC high voltage and AC high voltage, and compared with the traditional transformer which is only suitable for transmission of single-frequency and one-way voltage, the power electronic transformer can be almostsuitable for voltage two-way transmission under all conditions, frequency and voltage conversion is very flexible, and fault transmission at the two ends of the transformer can be effectively blocked.

The invention provides an intelligent video monitoring system for an internal state of an electric cabinet, and belongs to the intelligent technical field of the electric cabinet. The system comprises a measurement control device, a camera, a strong light and a fixing mechanism. An intrusion detection probe is connected with a control panel and a sound and light alarm module which are arranged out of the electric cabinet through the measurement control module. Moreover, the intrusion detection probe is also connected with a portable terminal or a network server at a control center. Real-time intelligent video monitoring is carried out on the internal state of the electric cabinet; a problem is discovered as early as possible and is discovered timely; and the electric cabinet is ensured to be always in a secure operation state. According to the system, any cabinet internal condition can be observed through the control panel, the control center or the portable terminal anytime; when there is the problem, the problem can be accurately located and timely processed; the power supply reliability is greatly guaranteed; the working efficiency is improved; and the security of an operator is ensured. The system is applicable to intelligent monitoring of the internal device or internal space security of the cabinet.

The invention relates to an information transmission control system and a method based on an overhead line wireless fault indicator. The system comprises a public network fore-placed computer, a data concentrator and a wireless fault indicator arranged on the overhead line. The wireless fault indicator arranged on the overhead line is connected onto the data concentrator by adopting a wireless cascade mode; the data concentrator is connected with the public network fore-placed computer in a wireless mode; and the public network fore-placed computer is connected with a power distribution network master station via a physical isolation device. the method comprises steps: the wireless fault indicator detects remote signaling displacement and telemetering information in the line and the remote signaling displacement and the telemetering information are uploaded to the public network fore-placed computer; and the public network fore-placed computer is matched with the power distribution network master station for realizing steps of overhead line fault information distribution and real-time telemetering information monitoring. The system and the method of the invention are reasonable, overhead line fault information distribution and real-time telemetering information monitoring function can be realized in a wireless channel transmission mode, and service application needs by the wireless fault indicator can be met.