231 results about "Dc circuit" patented technology

The invention relates to a ripple suppression PI loop control method, a storage medium and a device, and the method comprises the steps: extracting a frequency doubling component in an inversion power flow based on the filtering and Park transformation of a secondary second-order generalized integrator, determining the reverse compensation amount at each moment based on the frequency doubling component and a battery connected with a DC circuit, and carrying out the control of the ripple suppression PI loop. And finally, based on the sum of the reverse compensation amount at each moment and an original reference current value output by a voltage outer ring on each bridge arm of the DC circuit, determining a current reference instantaneous value after reverse compensation of a current inner ring input to each bridge arm at each moment. According to the method, a pure frequency doubling component with very high dynamic performance and related to ripple information is obtained, then according to the extracted frequency doubling component and battery parameters, the reverse compensation amount used for suppressing ripple in loop control is obtained, and then the reverse compensation amount is accumulated to a voltage outer loop, so that the ripple information is suppressed. Therefore, ripple suppression with good dynamic performance and good suppression effect in loop control is realized.

This invention relates to the field of DC circuit breakers, and discloses a thyristor-type DC circuit breaker and its control method. The DC circuit breaker structure is a thyristor T... m1 Anode-connected thyristor T m2 The cathode forms the A terminal of the circuit breaker, T m1 Cathode connection T m2 The anode of the thyristor forms the B terminal of the circuit breaker; the thyristor T p1 anode, thyristor T p2 The cathode is connected to terminal A; T p1 Cathode connection T p2 After anode, it passes through resistor R in sequence. g Switch RCB g Grounding; T p1 Cathode connection T p2 After the anode, it also passes through inductor L p Capacitor C is connected to terminal B; one end of the surge arrester MOV is connected to terminal T. p1 The cathode is connected to the first terminal, and the other end is connected to the B terminal. This invention has a simple structure and significant cost advantages; under normal operating conditions, only a single thyristor is conducting, resulting in extremely low losses and extremely high circuit breaker efficiency. Combined with control methods, it can actively and reliably connect or disconnect bidirectional operating current or bidirectional fault current; it can also achieve fast reclosing functionality.

This utility model discloses a substation emergency backup power supply system and a substation power outage control system. The substation emergency backup power supply system includes: a main control circuit, an AC-to-DC circuit, an auxiliary power supply, a battery module, a constant current charging circuit, a battery voltage acquisition circuit, a battery switching circuit, and a motor control circuit. The output terminal of the main control circuit is connected to the input terminal of the motor control circuit, enabling it to send control signals to the motor control circuit. The motor control circuit is connected to a drive mechanism, which is connected to the substation high-voltage switch, enabling it to control the switching action of the substation high-voltage switch. The substation emergency backup power supply system and substation power outage control system proposed in this utility model can improve the safety and intelligence of substation power outage shutdown.

The invention discloses an alternating current and direct current excitation device for a pumped storage unit excitation system, which comprises a direct current excitation loop, an alternating current excitation loop, a field suppression switch and a rotor loop, and is characterized in that the direct current excitation loop and the alternating current excitation loop are connected in parallel, the output end after parallel connection is connected with one end of the field suppression switch, and the other end of the field suppression switch is connected with the rotor loop; a connection path of the alternating current excitation loop comprises an alternating current power supply, an alternating current switch, a fuse F1, a transformer and a rectifier bridge, and a connection path of the direct current excitation loop comprises a direct current power supply, a direct current switch, a fuse F2, a divider resistor R1 and a diode. Isolation and mutual crossing prevention of an alternating current circuit and a direct current circuit are achieved through a rectifier bridge of the alternating current excitation loop and a diode of the direct current excitation loop, automatic mode switching is achieved in cooperation with an excitation regulator, seamless switching to the alternating current excitation loop can be achieved when the direct current excitation loop breaks down, and it is guaranteed that the pumped storage unit is reliably started when a power grid is dispatched emergently.

This invention provides a switching power supply, an AC-DC circuit, an input voltage detection circuit, and a method. The first end of the secondary coil of a transformer is connected to the anode of a rectifier diode, and the cathode of the rectifier diode is connected to the positive terminal of a filter capacitor. The second end of the secondary coil of the transformer, the negative terminal of the filter capacitor, and the positive terminal of the sampling capacitor are all grounded. The cathode of the diode is connected to the first end of the secondary coil of the transformer, and the anode is connected to the negative terminal of the sampling capacitor. The negative terminal of the sampling capacitor is grounded sequentially through a third sampling resistor and a second sampling resistor. The common terminal of the third and second sampling resistors is connected to a voltage detection terminal and, through a first sampling resistor, to a reference voltage input terminal. A reference voltage is input to the reference voltage input terminal. The control unit detects the voltage at the voltage detection terminal and calculates the magnitude of the input AC voltage based on the relationship between the AC voltage and the voltage at the voltage detection terminal.

An electric propulsion system for an aircraft, comprising: - an electrical power source (1) including a synchronous generator (11) driven by a heat engine (12), - a first synchronous electric motor (3) connected to an output of the synchronous generator by an alternating current electrical circuit (2), - a rotating propulsion unit (7), characterized in that it comprises: - a direct current electrical circuit (4) comprising, from an input connected to the alternating current electrical circuit: a first alternating / direct current converter (41), a direct current electrical link (42) and a second direct / alternating converter (43), - a second electric motor (5) connected to an output of the direct / alternating converter, - a differential gear train (6) including a first input shaft (61) connected to the first synchronous electric motor,a second input shaft (62) connected to the second electric motor and an output shaft (63) connected to the rotating propulsion unit. Figure for the abbreviation: Figure 1,

The present application provides a power supply device compatible with AC / DC input and a control method thereof, the device comprising a power factor correction circuit, a direct current-to-direct current (DC / DC) circuit, a bypass circuit, an input sampling circuit, and a controller. The power factor correction circuit is connected to the DC / DC circuit. The bypass circuit is connected to a boost circuit input end of the power factor correction circuit and an input end of the DC / DC circuit. The controller is connected to the input sampling circuit and the power factor correction circuit respectively, for controlling the power factor correction circuit to stabilize the output voltage within a preset range according to an input signal collected by the input sampling circuit, or turning off the power factor correction circuit and providing power for the DC / DC circuit via the bypass circuit.

In the RF-DC circuit of a wireless power receiving device, the device connected to the power supply voltage terminal is not protected. [Solution] In an RF-DC circuit of a wireless power receiving device, the RF-DC circuit comprises a capacitor provided between the positive terminal of the antenna and the power supply voltage terminal, and a diode connected in parallel with the capacitor and capable of outputting an overvoltage input from the positive terminal of the antenna to the GND output, wherein the RF-DC circuit is not connected to an overvoltage protection element between the positive terminal of the antenna and the capacitor.

This invention discloses an insulation detection method, device, and traction converter for the main circuit of a traction system, relating to the field of rail transit technology. The method includes: when in the insulation detection mode of the traction motor, blocking the pulses of non-target modules connected to the intermediate DC circuit and disconnecting the contactors of the non-isolated circuits connected to the intermediate DC circuit; using the grounding detection circuit in the intermediate DC circuit to obtain the insulation detection voltage information of the traction motor; and determining the insulation resistance to ground of the traction motor based on the insulation detection voltage information. This invention enables rapid and proactive identification and quantitative detection of the insulation resistance of the main circuit of the traction system while ensuring the existing functions of the traction converter remain unchanged. This allows for early identification of insulation performance degradation in the main circuit before a fault occurs, enabling vehicle users to accurately and reliably understand potential fault points in advance and take preventative maintenance measures, achieving intelligent early warning and autonomous real-time monitoring.

The invention relates to the technical field of signal switching, in particular to a signal switching structure, and solves the problems that in the prior art, a signal switching and assembling structure of an AC / DC circuit board is complex in assembling process, and assembling consistency is difficult to guarantee. The AC power terminal and the DC power terminal are installed in the socket shell, the low-voltage connector is used for collecting and leading out temperature signals, a DC cavity and an AC cavity are formed in the socket shell, the side edges of the DC cavity and the side edges of the AC cavity are communicated, and a circuit board assembly is arranged in the socket shell; the circuit board assembly comprises an AC circuit board installed in the AC cavity and a DC circuit board installed in the DC cavity, and the AC circuit board and the DC circuit board are electrically interconnected and mechanically fixed through a plug-in. The integrated circuit board assembly has the advantages that the AC circuit board and the DC circuit board are connected and fixed in advance through the plug-in to form the integrated circuit board assembly, synchronous assembly of the AC circuit board and the DC circuit board is achieved through the integrated structure, the assembly process is simplified, and deviation accumulation caused by step-by-step assembly is avoided.

The invention provides an equivalent test circuit and test method of a hybrid multi-port direct current circuit breaker, and an equivalent transfer branch, an equivalent energy consumption branch, a first equivalent switch branch and a second equivalent switch branch of the equivalent test circuit are connected in parallel and are all connected between a first port and a second port. A hybrid multi-port direct current circuit breaker is simplified into an equivalent test circuit with only two ports, functions of all transfer branches and energy consumption branches in the multi-port direct current circuit breaker are integrated through the equivalent transfer branch and the equivalent energy consumption branch, all ports and branches do not need to be re-etched, hardware investment and occupied area of a test platform are greatly reduced, and the test efficiency is improved. Meanwhile, only the first equivalent switch branch and the second equivalent switch branch which are directly related to the fault port are reserved, complex logic of multi-port cooperative control is avoided, the building difficulty and the operation and maintenance cost of the test system are remarkably reduced, and the test period is shortened.

1. The name of the design product: shunt (17). 2. The use of the design product: for sampling detection of current limiting, backflow, current sharing in DC circuit. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

Solid-state circuit breakers (SSCBs) have been witnessing an impressive progress with the aid of wide bandgap (WBG) devices such as silicon carbide (SiC) MOSFETs. Along with obtaining high efficiency as the result of low on-state resistance, response times have been gaining remarkable achievements in microseconds range. Not only that, the reported successes in control and gate drivers design and incorporating fault detection / location techniques in SSCBs are promising. A MOV-resistive capacitive switch (MOV-RCS) snubber for solid state circuit breakers addresses the following: 1) the MOV degradation issue in DCCBs is solved, 2) the maximum allowable DC bus voltage on DCCBs is extended. The solid state circuit breaker and an active clamping snubber includes a first circuit including a fault current bypass based solid state breaker for low voltage direct current systems.

1. The name of the design product: air-cooled power supply printed circuit board (60kw). 2. The use of the design product: component 1 is a direct current circuit board, component 2 is a power factor correction circuit board, both of which are used as printed circuit boards of air-cooled power supply modules. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: combined state diagram 1.

A smart home power control device includes an AC power input terminal, an AC-DC circuit, a DC voltage conversion circuit, a power distribution circuit, multiple power distribution branches, a multi-channel LED dimming control circuit, several power switches, and a controller. The input and output terminals of the AC-DC circuit are connected to the AC power input terminal and the voltage input terminal of the power distribution circuit, respectively. The voltage output terminal of the power distribution circuit is connected to the voltage input terminals of the multiple power distribution branches. The voltage output terminals of the multiple power distribution branches are connected one-to-one with the voltage input terminals of the multi-channel LED dimming control circuit. Several power switches are connected in series between the voltage output terminals of every two adjacent power distribution branches. The controller controls the operation of the power distribution circuit, the multiple power distribution branches, the multi-channel LED dimming control circuit, and the power switches. This invention enables a single power supply to power multiple loads and supports power sharing.

This application relates to a single-phase power conversion system, a three-phase power conversion system, and a control method thereof. The controller of the power conversion system determines whether to receive a corresponding shutdown signal by confirming the actual bus voltage values ​​of multiple power conversion modules. According to the control method described above, the power conversion system of this application prioritizes shutting down the power conversion modules with lower actual bus voltage values, thereby achieving bus voltage balance under extremely light loads. This increases the power entering the DC / DC circuit and gradually achieves voltage equalization among the multiple power conversion modules.

The application provides a DC-DC circuit and a power control method thereof. The method comprises the following steps: after detecting that an output end of the DC-DC circuit is connected to a charged device, requesting a maximum bearing voltage and a maximum bearing current from the charged device, until obtaining the maximum bearing voltage at a first time, calculating a limit current by taking a ratio of a test upper limit power and the maximum bearing voltage; during a period from a time when the charged device is connected to the first time: maintaining an output voltage at a default voltage, and maintaining an output current below a default current; during a period from the first time to a set time: maintaining the output voltage at the maximum bearing voltage, and maintaining the output current to be greater than the test upper limit current and below the maximum bearing current; after the set time: maintaining the output voltage at the maximum bearing voltage, and maintaining the output current below a smaller one of the test upper limit current and the limit current.

A DC-DC conversion circuit and an electronic device, the DC-DC conversion circuit comprising: a switching control circuit for outputting a control signal for controlling the switching circuit; the switching circuit is connected with the direct current input end and the switching control circuit and used for being switched on or switched off based on the control signal; the step-down circuit is connected with the switching circuit and is used for converting the input voltage of the direct current input end into output voltage based on turn-on and turn-off of the switching circuit; the charging circuit is connected with the step-down circuit and is used for charging a bus capacitor in the charging circuit based on the energy of the inductance follow current stage of the step-down circuit, and the bus capacitor can be used for supplying power to the switch control circuit and / or the feedback circuit; and the feedback circuit is connected with the step-down circuit and is used for sampling an output signal of the step-down circuit and feeding back the sampled signal to the switch control circuit. The direct current-direct current conversion circuit can solve the problems of high price, high standby power consumption and the like of an integrated chip scheme adopted by the existing direct current-direct current circuit.

The invention discloses a charging device, electronic equipment, a communication method and a charging system, and relates to the technical field of terminals. The charging device includes a first DC / DC circuit, a first charging circuit, a first battery, and a charging terminal. The first DC / DC circuit is used for charging the first battery by using the input direct current and outputting the direct current to the input end of the first charging circuit; the first charging circuit receives a first modulation signal sent by the electronic equipment, demodulates the first modulation signal, and sends a first modulation response signal to the electronic equipment when a demodulation result comprises a first current, the first modulation signal comprises the first current, and the first current is used for identifying that the electronic equipment initiates communication with the charging device; or, a second modulation signal is sent to the electronic equipment, a second modulation response signal sent by the electronic equipment is received, the second modulation signal comprises the first voltage, and the first voltage enables the second charging circuit of the electronic equipment to be disconnected from the second battery. According to the scheme, two-way communication between the charging devices can be realized.

The present disclosure provides a voltage presence indicator (VPI) circuit (100) for electrical safety application in electrical panel to indicate the presence of electrical potential of one or more electrical power input lines of an AC or DC circuit. The VPI circuit (100) includes plurality of voltage clipper circuits (VC1-VC5), bi-directional current limiter circuits (CL1-CL3), full bridge rectifier circuits (RC1-RC5), unbalance sensing circuits (SR1-SR2), signal conditioning circuits (S1-S2), comparator circuits (U1-U2), and flasher circuits (F1-F5). The flasher circuits (F1-F5) includes of plurality of solid state light emitting diodes (LEDs) disposed in a human viewable arrangement. The electrical circuitry of the VPI (100) converts electrical energy potential between the lines in the range of about 40 Volts to about 3000 volt into electrical inputs that drives the flasher circuit consisting of LEDs to produce light output.

The application belongs to the technical field of low-voltage electrical apparatus, and particularly provides a low-power under-voltage release based on relay driving, which comprises a surge absorption circuit, a rectification circuit, a DC / DC circuit, a voltage detection and release driving circuit, a starting time control circuit, a starting current control circuit, a release control circuit and a release coil; the rectification circuit is connected with the surge absorption circuit, the DC / DC circuit and the starting current control circuit respectively; the DC / DC circuit is further connected with the voltage detection and release driving circuit and the starting time control circuit respectively; the voltage detection and release driving circuit is further connected with the release control circuit; the release control circuit, the starting time control circuit and the starting current control circuit are connected in sequence; and the release control circuit and the starting current control circuit are both connected with the release coil. The low-power under-voltage release based on relay driving has the advantages of low power consumption, long service life, stable action voltage and the like.

The application discloses a control method and device of a vehicle-mounted charger, a vehicle-mounted charging system and a vehicle, and relates to the technical field of vehicle-mounted charging. The control method comprises the following steps: through controlling the action of the secondary side power switch tube of the isolation type DC / DC circuit in the vehicle-mounted charger, the pre-charging process of the DC bus capacitor is realized by using the electric energy of the power battery to charge the DC bus capacitor; the soft start of the isolation type DC / DC circuit is realized by gradually increasing the duty cycle at the start time, the oscillation of the resonance current is avoided, and the smoothness of the charging voltage output to the DC bus capacitor is improved; meanwhile, the loss in the isolation type DC / DC circuit is reduced by reducing the switching frequency after the duty cycle is stable, so that the gain of the output charging voltage is improved, and the fast charging of the DC bus capacitor is realized. The whole pre-charging process is realized by reusing the isolation type DC / DC circuit in the vehicle-mounted charger, no additional hardware is needed, and the application cost of the vehicle-mounted charger is effectively saved.

The invention discloses a pre-charging circuit of a multi-level converter, and is applied to the field of multi-level converter design. A current-limiting switch circuit and a first diode are added in a conventional DC / DC circuit, and the current-limiting switch circuit and the first diode are connected with a flying capacitor. The circuit is turned off when the input voltage of the DC / DC circuit is greater than the bus output voltage, and the input voltage charges the flying capacitor; and when the input voltage is smaller than the bus output voltage, the first bus capacitor, the flying capacitor and the first diode form a loop, and the flying capacitor is charged through the first bus capacitor, or the second bus capacitor, the first diode and the flying capacitor form a loop, so that the flying capacitor is charged through the second bus capacitor. Therefore, the circuit can charge the flying capacitor under any condition, so that the flying capacitor reaches half of the bus output voltage, and the phenomenon that starting cannot be completed due to voltage imbalance is avoided.

The application provides a bidirectional DCDC circuit and a control method thereof. In the bidirectional DCDC circuit, a first power module, a second power module, a main circuit, a first sampling circuit, a second sampling circuit, a first driving circuit, a second driving circuit and a controller are correspondingly connected, so that the topology structure and the circuit loop can be simplified, and the device cost is reduced. When the power is transmitted between the first power module and the second power module, the controller determines the target ratio combination of the main circuit according to the first regulating signal and the second regulating signal, and then controls the main circuit to switch to the target ratio combination based on the switching control signal through the first driving circuit and the second driving circuit, so that the input and output voltage and the input and output current of the main circuit are controlled according to the target ratio combination, the unified driving signal is used for driving, and the stability of the output voltage and current is ensured.

The invention discloses an energy storage battery heating method, equipment and a medium. The method comprises the following steps: constructing a current reference of a battery cluster, wherein the current reference comprises a direct-current component and an alternating-current component; performing phase distribution on the alternating current component corresponding to each battery cluster, so that the vector sum of the alternating current components corresponding to all the battery clusters subjected to phase distribution is zero; and generating a heating current instruction of the battery cluster according to the current reference after the phase distribution is completed, and inputting the heating current instruction to the corresponding bidirectional DC / DC circuit. The device and the medium are both used for implementing the method. The beneficial effects of the invention are that the technical scheme is implemented completely based on an existing current control architecture, extra devices such as a heating sheet, a PTC, an H-bridge heating unit and the like are not needed, cost rise and reliability hidden dangers caused by hardware extension are avoided, and direct deployment in an existing energy storage platform is facilitated.

The utility model discloses a vehicle-mounted TBOX low-voltage starting prevention switching circuit which is composed of a power input circuit, a protection circuit, a decoupling circuit, a fuse, a slow starting circuit, an MOS switching tube circuit, a filter circuit, a decoupling circuit, a low-voltage starting prevention circuit and a system main power supply DC / DC circuit. The protection circuit comprises an electrostatic, filtering and anti-surge circuit; the low-voltage starting prevention circuit is controlled to start by elements such as a Zener diode. When the vehicle-mounted battery supplies power, the circuit is subjected to multiple processing, and when the voltage is lower than a safety threshold value, the TBOX communication terminal is prevented from being started, battery discharging is slowed down, premature over-discharging is avoided, meanwhile, the problems that the input voltage is too low, and a power supply is frequently started for power failure are solved, and stable operation of the vehicle-mounted battery and a TBOX system is effectively guaranteed.

The invention discloses a grid-connected current distortion suppression method for a miniature single-phase bidirectional grid-connected inverter. The method comprises the following steps: respectively acquiring primary bus voltage at a first moment and a second moment of a current switching period to obtain first voltage and second voltage; calculating a bus voltage actual value based on the collected data; extracting fluctuation characteristics based on the bus voltage actual value, updating a preset bus voltage mathematical model to obtain a target bus voltage data model, and smoothing the bus voltage actual value to obtain a bus voltage average value of the current switching period; and calculating a theoretical predicted value of the bus voltage based on the target bus voltage data model and the average value of the bus voltage, and performing closed-loop control on the miniature single-phase bidirectional grid-connected inverter through the theoretical predicted value of the bus voltage. According to the method, bus fluctuation can be decoupled, under the condition that multiple DC / DC circuits are connected to the bus for energy input or output, the inverter side can still stably control the average voltage value of the bus, grid-connected current distortion is effectively restrained, and the electric energy quality is improved.

The invention relates to an SEPIC-ZETA bidirectional DC-DC efficient converter based on improved RCD passive absorption and active clamping. The SEPIC-ZETA bidirectional DC-DC efficient converter comprises a bidirectional DC-DC isolation conversion module, a first-stage RCD clamping absorption unit, a second-stage RCD clamping absorption unit, a third-stage RCD clamping absorption unit and an active clamping circuit module. According to the bidirectional DC-DC high-efficiency converter, stress of a switch tube can be effectively clamped when the SEPIC-ZETA works bidirectionally, meanwhile, energy of leakage inductance is absorbed through the corresponding RCD clamping absorption unit and fed back to a bus to be utilized, and the working efficiency and the dynamic performance of the isolation converter are greatly improved. Through efficiency optimization and the working characteristics of the SEPIC-ZETA circuit, the converter can be better suitable for a DC-DC bidirectional circuit, and PWM closed-loop control is used under the condition that the efficiency of the converter is kept, so that the converter can be better applied to more power supply devices such as an energy storage inverter, a UPS, a server power supply and the like.