85 results about "DC distribution system" patented technology

Voltage command values are set according to voltage fluctuations of a plurality of power supply sources, and one of outputs from a plurality of power supply circuits which output DC voltages obtained by performing conversion according to the voltage command values is supplied to a power conversion circuit as control power so that the system can be continuously operated even at the time of an abnormality due to a device failure and a power outage, and control power consumption can be suppressed in the case of voltage fluctuations of the power supply sources.

The invention relates to the technical field of power electronics and power supply and distribution, and discloses a data center AC / DC power distribution system input and output voltage and current monitoring method, which comprises the following steps: deploying an intelligent sensing unit with edge computing capability at each monitoring node, sampling according to a basic frequency, and extracting effective values, harmonic distortion rates, differential change rates and other characteristics of voltage and current in real time; judging that the system is in a steady state, a quasi transient state or a strong transient state according to the multi-stage dynamic threshold value, and respectively executing feature abstract uploading, local high-frequency backtracking or collaborative full-waveform synchronous acquisition; and the central server classifies and stores the data, constructs a state evolution model, and dynamically optimizes threshold parameters. The system comprises an intelligent sensing unit, a central monitoring server and an industrial Ethernet link. According to the method, the steady-state data transmission quantity is remarkably reduced, transient details are completely captured, and adaptive adjustment of the monitoring sensitivity is realized.

The invention belongs to the technical field of ship power distribution, and particularly discloses a double-bus redundant direct-current power distribution system for a ship. Comprising a first direct-current busbar left, a first direct-current busbar right, a second direct-current busbar left, a second direct-current busbar right, a first circuit breaker, a second circuit breaker, a lithium battery pack, a first propulsion inverter cabinet, a first daily inverter cabinet, a second propulsion inverter cabinet, a second daily inverter cabinet, a direct-current voltage stabilizer and a system charging socket box. According to the invention, through setting the first direct-current busbar left, the first direct-current busbar right, the second direct-current busbar left, the second direct-current busbar right and the switching relation thereof, and adopting an operation mode that one group of busbars works and the other group of busbars is standby, flexible and balanced distribution of a power supply and a load is realized, and all loops can work without power failure; once any busbar or branch has a fault, the standby busbar is immediately started so as to start the standby loop, so that no power loss and no power reduction of the whole ship are ensured, and all equipment and components of the whole system are subjected to redundancy design so as to ensure that the power distribution system always supplies power normally.

To provide a load control device that suppresses a voltage rise on a DC bus even if a plurality of loads simultaneously generate regenerative power.SOLUTION: A DC power distribution system includes a DC bus, a plurality of regenerative loads connected to the DC bus, a storage battery connected to the DC bus via a DC / DC converter, and a load control device that performs regeneration control of the loads. The load control device includes a storage unit that stores regenerative power data of the loads and a preset upper limit charge power when charging the storage battery, and a control unit that controls the regeneration start time of each of the plurality of loads so that the upper limit charge power is not exceeded during the regenerative operation of the plurality of loads.SELECTED DRAWING: Figure 1

The invention discloses an electric tug energy efficiency management method based on a large model, and the method comprises the following steps: S1, energy dynamic distribution optimization: carrying out the optimization of energy dynamic distribution based on the large model according to the real-time load of an electric tug; s2, charging strategy optimization: according to the price gradient of the power grid, the charging time and the charging electric quantity of the electric tug are optimized; s3, safety protection of the battery system: monitoring the temperature, voltage and current of the battery in real time, and performing early warning protection on the battery; s4, safety guarantee of the propulsion system: monitoring operation data of the propulsion system in real time, and performing protection, fault monitoring and fault diagnosis on the propulsion system; s5, safety redundancy of the power supply system: monitoring and adjusting the electric energy quality of the DC power distribution system, and supplying emergency power to the AC power distribution system; according to the method, accurate power distribution, intelligent charging management, efficient safety protection and reliable power supply guarantee are achieved, and the energy efficiency and operation safety of the electric tug are improved.

This invention discloses an active damping control method for bipolar DC distribution systems based on modulus decomposition. It incorporates line coupling into the system's stability criteria and active damping parameter design, deriving the pole-mode transformation matrix of the metal-return bipolar DC distribution system and obtaining a decoupling model of the bipolar DC line in the modulus component space. The modulus models of the source-side converter and load are also derived. Based on the established decoupling model of the bipolar DC distribution system in the modulus component space, an active damping control method based on modulus decomposition is proposed. This invention considers the impact of DC distribution lines on stability, incorporating line coupling into the system's stability criteria and active damping parameter design. The modulus damping control scheme proposed in this invention can more effectively suppress instability caused by the negative impedance characteristics of constant power loads and also provides a basis for parameter adjustment.

The application provides a DC power distribution network source-load-storage self-adaptive power distribution method based on flexible droop control, aiming at coordinating the logical relationship between the maximum power constraint of new energy, the residual capacity constraint of energy storage equipment and the controllable range constraint of load and the voltage-power droop control in the DC power distribution network, meanwhile, the application determines a droop coefficient setting method in the form of power standard, provides a unified droop coefficient setting rule for equipment of different categories, capacities and rated powers, and ensures that each equipment can determine the quota participating in the self-adaptive power distribution according to the current working condition under the droop coefficient setting scheme, compared with the existing scheme, the self-adaptability of the power distribution among the source, the load and the storage in the DC power distribution system is improved.

An alternating current to direct current (AC to DC) power converter assembly that converts a plurality of low voltage alternating current (AC) inputs into a high voltage DC power output. The converter includes two or more AC to DC power converters, each of the two or more AC to DC power converters including: a low power AC power input configured to receive an AC input from a low power AC power source; and a low power DC power output. The converter also includes two or more isolated DC to DC power converters, each DC to DC power converter electrically coupled at least one of the AC to DC power converters, wherein each DC to DC power converter includes an output and wherein each of the DC to DC power converters are connected in series to produce the high power DC power output.

The disclosure provides a method of detecting arc faults in a DC power distribution system. The method comprises: sampling, using one or more sensors, a voltage signal on a conductor forming a current path of the power distribution system to generate a voltage signal sample vector; sampling, using the one or more sensors, a current signal in the conductor to generate a current signal sample vector; generating one or more feature vectors based on the voltage signal sample vector and the current signal sample vector and having fewer elements than the current signal sample vector or the voltage signal sample vector; providing the one or more feature vectors to an arc fault classification model; and receiving as an output of the arc fault classification model an indication of whether an arc fault is occurring in the power distribution system.

The application discloses a kind of grid-connected detection method, equipment, medium and product of AC-DC distribution system, the method includes: establishing the power flow model of AC-DC distribution system before distributed power grid connection, and according to power flow model obtains time series power flow result, the reliability calculation of AC-DC distribution system is carried out, obtains reliability calculation index, according to time series power flow result and reliability calculation index, the comprehensive performance index of AC-DC distribution system is constructed, according to comprehensive performance index, the operation state information of AC-DC distribution system is generated for distributed power grid connection.According to operation state information, the weak link that AC-DC distribution system needs to be reformed can be determined, and technical support and guidance can be provided for distributed power grid connection strategy, which is conducive to promoting the safe and reliable operation of AC-DC distribution system.Through optimization scheduling and power supply planning, the operation efficiency of AC-DC distribution system can be improved, the operation cost is reduced, and the accuracy of grid-connected detection of AC-DC distribution system is improved.

The embodiment of the invention provides a mining DC power distribution system. In one specific embodiment, the system comprises a rectification filtering unit, an energy storage assembly, a first power-off change-over switch, a second power-off change-over switch, relay power generation equipment and a controller. The controller is used for acquiring a first conversion state of the first power-off automatic conversion switch, responding to the first conversion state as an instruction that the output end of the first power-off automatic conversion switch is connected with the standby input end, controlling the power generation equipment to be started, acquiring an operation state of the power generation equipment, responding to the operation state as an operation ready instruction, and controlling the power generation equipment to be started. And the coil of the relay is controlled to be electrified. The mining DC power distribution system can stably and continuously supply power for a long time.

The present application relates to the field of power electronics and power supply and distribution technology, and discloses a monitoring method for input and output voltage and current of an AC / DC power distribution system in a data center, which comprises: deploying intelligent sensing units with edge computing capabilities at each monitoring node to sample at a basic frequency and extract real-time characteristics such as effective value, harmonic distortion rate and differential change rate of voltage and current; determining whether the system is in a steady state, quasi-instantaneous state or strong instantaneous state according to multi-level dynamic threshold values, and performing feature abstract upload, local high-frequency backtracking or collaborative full-waveform synchronous acquisition respectively; storing data in a central server and constructing a state evolution model to dynamically optimize threshold parameters. The system comprises intelligent sensing units, a central monitoring server and an industrial Ethernet link. The present application significantly reduces steady-state data transmission volume, completely captures transient details and realizes adaptive adjustment of monitoring sensitivity.

The invention discloses a direct-current system ground fault detection method and system, and the method comprises the steps: respectively connecting resistors with equal resistance values between a positive bus and a negative bus of a direct-current system and the ground to form a symmetric resistance network, and collecting positive / negative voltage to ground and the grounding current of each branch in real time; extracting a high-frequency component through wavelet transform and energy entropy analysis to generate a frequency domain mark; performing wavelet transformation and energy entropy calculation on the grounding current signal, and extracting a high-frequency detail component; and a hierarchical collaborative decision is executed, immediate tripping is triggered by double marks, a delay recheck mechanism is started by single mark triggering, tripping is executed after continuous triggering, and a fault is positioned and reported. According to the technical system, the comprehensive identification speed of the grounding fault of the direct-current system is improved, full-process closed-loop protection of rapid sensing and identification, reliable decision making and accurate positioning is formed, and the operation safety of the direct-current power distribution system is improved.

The application provides a Kun-type hybrid polarity direct current power distribution system and a four-transformer QAB converter h1 The positive pole of the high-voltage side bus is connected to the high-voltage side active bridge H l1 The positive pole of the low-voltage side bus is connected to the high-voltage side active bridge H h2 The negative pole of the high-voltage side bus is connected to the low-voltage side active bridge H l2 The negative pole of the low-voltage side bus is connected to the high-voltage side active bridge H h1 The high-voltage side active bridge H l1 is connected to the low-voltage side active bridge H r1 through a high-frequency transformer T h2 The high-voltage side active bridge H l2 is connected to the low-voltage side active bridge H r2 through a high-frequency transformer T l1 The low-voltage side active bridge H h2 and the high-voltage side active bridge H e1 are connected through a transformer T h1 The low-voltage side active bridge H l2 and the high-voltage side active bridge H e2 are connected through a transformer T The Kun-type hybrid polarity direct current power distribution system provided by the application has the function of true bipolar system interconnection and guarantees electrical isolation between bipolar systems, thereby ensuring the safety of user power supply.

The application provides a method and system for simulating operation of a direct current power distribution system with an energy storage device, comprising: setting an initial value of a direct current voltage in the direct current power distribution system; reading a control mode of a voltage source converter and the energy storage device in the direct current power distribution system and a state of charge of the energy storage device; adjusting the control mode of the voltage source converter and the energy storage device according to the initial value of the direct current voltage in the direct current power distribution system and the state of charge of the energy storage device; and performing power flow simulation calculation on the power distribution system after the control mode of the voltage source converter and the energy storage device is adjusted. The method and system can effectively cope with the characteristics of the energy storage device in the direct current power distribution system, such as the changeable state of charge and the flexible adjustment of the control mode, and meet the power flow calculation requirements of the direct current power distribution system with the energy storage device.

The invention provides a DC micro-grid insulation resistance monitoring device for an optical storage DC flexible system. The DC micro-grid insulation resistance monitoring device comprises a detection circuit and a controller communicating with the detection circuit. The device is connected to multiple paths of positive direct current buses including distributed photovoltaic branches and energy storage system branches in a direct current micro-grid through a Y-shaped connecting circuit, and relay logic is switched by utilizing a controller to obtain an output voltage signal. The core judgment logic is to compare whether the output voltage is in a reasonable interval defined by a coefficient gamma (the value can be dynamically adjusted according to the energy storage voltage grade) and the bus voltage, so that the insulation abnormity of the direct current micro-grid system under the flexible interaction working condition is quickly identified, and an alarm is given. According to the device, the operation process of multi-branch complex impedance is simplified, and the detection efficiency of the ground insulation state of the direct current end is remarkably improved.

The invention relates to a temperature control system control method and device, computer equipment and a storage medium, and relates to the technical field of temperature control. The method comprises the following steps: acquiring the bus voltage of a direct current power distribution system of a building where the temperature control system is located and the state information of the temperature control system, and determining the set temperature of the temperature control system by using a prediction model of the temperature control system according to the bus voltage and the state information; wherein model parameters of the prediction model are respectively related to the temperature control system and the building where the temperature control system is located, the temperature control system is controlled according to the set temperature, and the output power after the temperature control system is controlled is smaller than the output power when the temperature control system starts to be controlled. By adopting the method, flexible operation of the temperature control system can be controlled, power consumption is reduced, and the purposes of low power consumption and low carbon are achieved.

The invention discloses an optimal power flow calculation method for a multi-voltage-class bipolar direct-current power distribution system. The method comprises the following steps: 1, constructing a power flow decoupling model of a bipolar direct-current power distribution network; 2, constructing a direct current transformer DCT interelectrode decoupling and control model; 3, constructing a multi-voltage-level bipolar direct current optimal power flow model; 4, constructing an optimal power flow linearization and second-order cone relaxation model; and 5, obtaining the optimal power flow distribution of the system by solving the multi-voltage-level direct-current power distribution system network, and realizing stable and safe operation of the direct-current power distribution network. According to the method, the voltage quality of the direct current power distribution system can be ensured to be within an operation allowable range, so that the bipolar direct current power distribution network realizes higher electric energy quality and better power flow distribution, and safe and stable operation of the system is ensured.

The application discloses a direct current system grounding fault detection method and system, equal resistance is connected between the positive and negative bus of the direct current system and the ground to form a symmetrical resistance network, the positive / negative ground voltage and the branch ground current are collected in real time, the voltage deviation is calculated to generate a time domain fault mark, a high frequency component is extracted by wavelet transform and energy entropy analysis to generate a frequency domain mark, the ground current signal is subjected to wavelet transform and energy entropy calculation to extract a high frequency detail component, hierarchical collaborative decision is executed, double mark triggering immediately trips, single mark triggering starts a delay review mechanism, and after continuous triggering, tripping is executed and fault positioning and reporting are performed. The technical system improves the comprehensive identification speed of the direct current system grounding fault, forms a whole-process closed-loop protection of fast sensing and identification, reliable decision and accurate positioning, and improves the operation safety of the direct current distribution system.

The invention discloses a direct-current power distribution system energy mutual aid and power coordination control method, application and system, aiming at non-ideal disturbance, load fluctuation and parameter uncertainty existing in the system, VFESO is introduced, rapid estimation and compensation of generalized disturbance are realized through self-adaptive adjustment of observation gain and feedback bandwidth, and based on an observation result of the VFESO, the energy mutual aid and power coordination control of the direct-current power distribution system is realized. An improved reference feed-forward control law is designed, the reference current change rate and the disturbance observed quantity are comprehensively considered in the control law, a disturbance compensation item is directly introduced into control input, and feed-forward compensation and dynamic linearization of a current control loop are achieved; according to the invention, the system can maintain high-precision voltage and power control under the conditions of new energy fluctuation, energy storage switching and load disturbance.

To quickly and accurately detect an incident generated in a DC power distribution system.SOLUTION: A DC power distribution system for distributing power from a power supply device to a load device via a power distribution network comprises: a measuring instrument provided in the power distribution network, the measuring instrument comprising a nano optical modulator for converting a measured value of an electric signal to an optical signal for transmission using an optical fiber; and a controller comprising a determination unit that acquires a voltage value and current value measured by the measuring instrument using a nano optical receiver for converting the optical signal to an electric signal through the optical and determines an operation state of the DC power distribution system on the basis of predetermined information on the voltage value and the current value. The determination unit determines that any of states of inrush current, load connection, load ON / load OFF, and load fluctuation has occurred as the operation state.SELECTED DRAWING: Figure 1

The invention relates to a solid-state switch fault protection system for a direct-current power distribution system, which is applied to a ship direct-current power distribution system, the ship direct-current power distribution system comprises a direct-current bus, the direct-current bus is divided into a left direct-current bus and a right direct-current bus, and the left direct-current bus and the right direct-current bus are connected through a solid-state switch. The solid-state switch fault protection system comprises an energy management system, a converter and the like which are connected with a ship direct-current power distribution system, a power supply is connected with a direct-current bus through the converter, a propelling system is connected with the direct-current bus through a motor driver module, and a side propelling system is connected with the direct-current bus through a power inverter module. The energy management system adopts a redundant PLC control system based on a looped network so as to quickly monitor faults of the solid-state switch, and can quickly provide a control scheme according to an online system. In addition, the system has the advantages of good stability, safety and the like.

The application relates to the technical field of shell circuit breakers, and provides a compact DC molded case circuit breaker and a DC power distribution system. The compact DC molded case circuit breaker comprises a shell, an operating mechanism and an arc extinguishing module, two arc extinguishing cavities are arranged in the shell, the operating mechanism comprises an operating unit and a first rotating shaft which are connected with each other, one end of the operating unit is located outside the shell, the first rotating shaft is located in the shell, and the operating mechanism is located between the two arc extinguishing cavities; the arc extinguishing module is arranged in each arc extinguishing cavity, the arc extinguishing module comprises a second rotating shaft, a first grid group, a second grid group, a third grid group and a contact assembly, the first grid group and the second grid group are oppositely arranged on the two sides of the contact assembly, the third grid group is arranged on one side of the contact assembly, and the first grid group, the second grid group, the third grid group and the contact assembly form a leaving area for accommodating the contact assembly. The application can maximize the arc extinguishing cavity volume and the wiring space within a specific width.

The invention relates to the technical field of building direct-current power supply and distribution and power electronic control, and discloses a double-ring multi-module phase-shifting soft switching coordination control method, system and device for a B2G converter and a medium, and the method comprises the steps: achieving the performance optimization of the B2G modular converter in a steady-state, high-dynamic and wide-load range through a pure software control means. On the premise that the hardware topology is not changed, the full load efficiency of the system reaches 97% or above, and the efficiency is reduced by less than 2% when the load is 20%. The DC bus voltage is stable during load fluctuation, the controllable transition time is very short, and no impact current or overvoltage exists during bidirectional power switching; the power modules are balanced in heating, stress is reduced, and overall reliability is improved. The control strategy can be widely applied to current conversion equipment of an optical storage DC flexible DC power distribution system, and has remarkable popularization potential.

This invention discloses an adaptive DC voltage control method for a three-terminal flexible DC distribution system, belonging to the field of power technology. The method includes the following steps: constructing a three-terminal flexible DC distribution system; analyzing the deviation value of the DC voltage in the three-terminal flexible DC distribution system; determining the magnitude of the DC voltage deviation value; and controlling the change and voltage value of the DC voltage in the three-terminal flexible DC distribution system. This invention superimposes an active power command correction controller onto the constant power control mode (PQ mode) of the flexible DC converter, enabling the flexible DC converter to dynamically adjust the output active power according to the instantaneous state of the DC voltage, thereby improving the DC voltage recovery speed.

The application discloses a kind of topology circuit, device and method of active promotion equipment of direct current power supply quality, circuit includes: double active converter DAB and direct current active filter DC-APF;Device includes direct current distribution system power quality management circuit and control module;Method includes: real-time detection whether there is voltage deviation and direct current ripple condition;When detecting voltage deviation, control the conduction of diagonal switch tube in first DC-APF and second DC-APF;When detecting direct current ripple, control first DC-APF and second DC-APF output reverse compensation current to suppress ripple;The application can realize voltage, harmonic self-regulating coordination, with direct current ripple management, voltage deviation suppression capability.

The invention relates to a flexible interconnection device-based self-adaptive multi-target cooperative scheduling method for a power distribution area, and belongs to the technical field of electric power. The method takes minimization of voltage fluctuation and flexible load fluctuation of an AC / DC power distribution system as a target, an optimization target function is constructed, and meanwhile, SOP power constraint, system power flow constraint, system operation safety constraint, energy storage constraint and flexible load constraint are taken as constraint conditions; dividing the operation mode of the transformer area, and then respectively constructing dynamic weight coefficients in a steady-state operation mode, a voltage early warning mode and a secondary voltage recovery mode; and solving the optimization objective function, and scheduling according to a solving result. According to the method, multi-target collaborative optimization is realized, and the economic operation and source load fluctuation impact coping capability of each transformer area in the power distribution transformer area are improved; by detecting voltage fluctuation in real time, the adjusting function of a controllable device can be fully played, the system power flow can be rapidly and accurately adjusted, and economical and reliable operation of the system is achieved.

The application discloses a three-phase grid-connected converter control method, a circuit, a device and a medium, and relates to the technical field of AC-DC power distribution systems. The three-phase grid-connected converter control method provided by the application establishes a mathematical model of the three-phase grid-connected converter, combines the causes and suppression mechanism of the leakage current, controls the filter capacitor voltage in the zero sequence loop to be a constant value through a PI regulator, and effectively attenuates the leakage current. The phase angle of the grid voltage is obtained in a three-phase stationary coordinate system, the sampling quantity is coordinate-transformed according to the angle, a modulation signal is obtained, and the power switch tube in the grid-connected converter is controlled according to the modulation signal. Since only one connected wire needs to be added between the middle point of the filter capacitor and the common point of the lower bridge arm in the scheme, the cost is low, and the leakage current caused by the existence of the parasitic capacitance of the DC side power distribution device to the ground can be limited to the microampere level.

The invention discloses a multi-dimensional multi-resource comprehensive voltage regulation and control optimization method for a multi-voltage-class bipolar direct-current power distribution network. The method comprises the following steps: 1, establishing control models of a bipolar direct-current transformer DCT, an electric vehicle, energy storage equipment and a power flow controller; 2, establishing a multi-dimension multi-resource coordination control model of the multi-voltage-level bipolar direct current power distribution network; 3, establishing a comprehensive voltage regulation and control optimization model of the multi-voltage-level bipolar direct-current power distribution network; 4, establishing a linearization and relaxation model constrained by the bipolar direct-current power distribution network comprehensive voltage regulation and control model; and 5, obtaining a comprehensive voltage regulation and control optimization strategy of the bipolar direct-current power distribution system by solving the multi-voltage-level bipolar direct-current power distribution network. According to the method, the load demand and the distributed energy fluctuation can be quickly responded, the stability of the voltage at the low-voltage side is ensured, the problems of voltage unbalance degree and out-of-limit between the positive electrode and the negative electrode are effectively controlled, and the stability of the system voltage is improved.

This DC power distribution system supplies power from power supplies (20, 21) through a DC bus (2) to a plurality of devices (23, 24, 25, 26) in a logistics warehouse, and comprises: first power converters (10, 11) that supply power unidirectionally from the power supplies (20, 21) toward the DC bus (2); second power converters (13, 14, 15) that supply power bidirectionally between the DC bus (2) and built-in storage battery loads (23, 24, 25); a third power converter (16) that supplies power bidirectionally between the DC bus (2) and a motor load (26); and a control device (1) that instructs the first power converters (10, 11) and the second power converters (13, 14, 15) to transmit a target voltage value on the DC bus side and operation parameters being the power conversion directions.