408 results about "Dc circuit" patented technology

The invention discloses a charging and discharging control method and device for an elevator energy storage system, a medium and a product, and relates to the field of data processing. The method comprises the steps that real-time operation data such as the position and the load capacity of an elevator car are obtained, and the instantaneous power generation power and the power change rate of a traction machine are determined accordingly; determining a power change predicted value in a future preset time period based on the parameters, and obtaining the total amount of power generation energy required to be stored by the energy storage system through zero setting of a positive value, integral operation and efficiency compensation; according to the power change rate, the state of the energy storage unit and the power grid electricity price time period, the charging and discharging priorities fed back by the super capacitor, the lithium battery and the power grid are determined; controlling the bidirectional DC / DC circuit to switch charging and discharging modes according to the priority, and adjusting the PWM duty ratio of the brake resistor; and based on the charging and discharging mode and the duty ratio, charging and discharging control over the elevator energy storage system is achieved. According to the method, the problem of inaccurate real-time matching of the dynamic load and the energy fluctuation of the current elevator energy storage system can be relieved.

The utility model provides an electric energy meter calibrating device comprising a calibrating box body, the calibrating box body comprises a first plate and a second plate which are arranged at intervals along a first direction, and at least one of the first plate and the second plate is provided with at least one first air port; the second air opening is formed in the plate body for connecting the first plate and the second plate; the supporting partition plate is arranged in the verification box body in the first direction, and the space in the verification box body is divided into a first cavity and a second cavity by the supporting partition plate; the plurality of direct-current circuit boards are connected with the supporting partition plate, the direct-current circuit boards are arranged in the first cavity, and at least one direct-current circuit board is provided with a first heating piece; the at least one first fan is arranged on the supporting partition plate, and the first fan and the first heating piece are oppositely arranged; and the plurality of alternating-current circuit boards are connected with the supporting partition plate and are arranged in the second cavity. According to the technical scheme, the direct current circuit board and the alternating current circuit board are arranged in a layered mode, the heat dissipation capacity of the device is remarkably improved, and the temperature of the whole system is kept stable.

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 energy storage technology and discloses a synchronous testing platform for multiple energy storage converters and its control method. The testing platform of this invention includes: an incoming line switch, a pre-charge circuit, a transformer, an auxiliary power supply switch, an AC circuit breaker, a DC circuit breaker, and a unit controller. The power grid is connected to the high-voltage side of the transformer sequentially through the incoming line switch and the pre-charge circuit. One side of the AC circuit breaker is connected to the windings on the low-voltage side of the transformer, and the other side is connected to the AC side of the energy storage converter. The DC side of the first group of energy storage converters is connected to the DC side of the second group of energy storage converters through DC circuit breakers. The first group of energy storage converters is connected to the auxiliary power supply. In this invention, after the first group of PCS (Power Storage Converters) is pre-charged, the pre-charge circuit is bypassed. Then, the first group of PCS is unlocked and controlled in DC voltage mode, and the second group of PCS is started sequentially, thereby achieving synchronous charging and discharging testing of 2N PCS, greatly improving the charging and discharging testing efficiency of the energy storage converter.

The invention relates to the technical field of vehicle charging sockets, in particular to a charging socket signal switching mode. According to the charging socket signal switching mode, a socket shell is included, an inner cavity of the socket shell is divided into a DC cavity and an AC cavity, a DC circuit board and an AC circuit board are connected with SMD thermistors respectively so as to measure the temperature of DC and AC power terminals, the DC circuit board and the AC circuit board are connected with multi-PIN connectors respectively, and multi-PIN contact pins are integrated in the socket shell. The two ends of the multi-PIN pin extend into the DC cavity and the AC cavity respectively and are connected with the multi-PIN connector of the DC circuit board and the multi-PIN connector of the AC circuit board in an inserted mode, so that a DC power terminal temperature signal is transmitted to the AC circuit board through the multi-PIN connector of the DC circuit board, the multi-PIN pin and the multi-PIN connector of the AC circuit board in sequence and led out through the low-voltage connector of the AC circuit board. Through a signal switching mode of integrating the PINs in the socket shell, the split type design of the AC cavity and the DC cavity can be realized, so that the assembling performance and the sealing reliability of the product are improved.

The embodiment of the invention discloses a primary and secondary fusion pole-mounted switch self-adaptive energy supply system and method, and relates to the technical field of intelligent power distribution network equipment. The system comprises a capacitor electricity taking module located on the primary side of the primary and secondary fusion pole-mounted switch, and a super capacitor, a power management module, a storage battery, an energy management control unit and a DC-DC circuit which are located on the secondary side of the primary and secondary fusion pole-mounted switch. Dynamic coordination of two energy storage elements, namely a super capacitor and a storage battery, in a steady-state low-power-consumption monitoring and transient-state high-power driving scene is realized, energy distribution optimization, closed-loop charging guarantee and abnormal fault-tolerant design are combined, and the problems of high steady-state power consumption and insufficient transient-state driving capability existing in a traditional primary and secondary fusion pole-mounted switch power supply scheme are solved.

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.

The application discloses a fault current analysis method and system of a multi-terminal flexible DC circuit, wherein the method comprises the following steps: analyzing fault current data when a modular multilevel converter DC side is short-circuited to obtain time sequence segmentation rule data; performing equivalent processing on the modular multilevel converter based on the segmentation rule data to obtain an equivalent circuit model comprising an RLC series circuit and a time-varying current source; constructing a second-order differential equation describing the fault current according to the equivalent circuit model, and solving the second-order differential equation to obtain a fault current expression containing dynamic AC feed-in; constructing a fault equivalent network of the multi-terminal flexible DC circuit; constructing a state space equation of the fault equivalent network based on a branch current method and the fault current expression, and solving the state space equation to obtain fault current data of the multi-terminal flexible DC circuit. The method improves the accuracy of fault analysis.

The present application discloses a variable frequency power supply device with dual-circuit electric energy balance, which includes a rectifier unit, two inverter units, two DC circuits, two voltage collection units, an energy transmission unit, and an energy balance control unit. The input end of the rectifier unit is connected to the AC power grid; the output ends of the two inverter units are used to be connected to two loads respectively; the two ends of the two DC circuits are respectively connected to the output end of the rectifier circuit and the input end of the two inverter units; the two voltage collection units are respectively connected to the two DC circuits; the two ends of the energy transmission unit are respectively connected to the two DC circuits; and the energy balance control unit is connected to the two voltage collection units, the energy transmission unit, and the two inverter units. The variable frequency power supply device with dual-circuit electric energy balance makes the voltages of the two DC circuits tend to a balanced voltage, thereby achieving a complementary state of electric energy for the two loads, reducing power consumption, and preventing power accumulation and impact on the AC power grid.

The application discloses a bidirectional DCDC circuit and a photovoltaic energy storage inverter. The photovoltaic energy storage inverter is used for connecting a photovoltaic module, a battery and an alternating current end. The bidirectional DCDC circuit comprises a first direct current end, a second direct current end, a transformer, a first full-bridge circuit connected between the first direct current end and a primary side of the transformer, a second full-bridge circuit connected between a secondary side of the transformer and the second direct current end and a first capacitor. The first full-bridge circuit is directly connected with the primary side of the transformer and / or the second full-bridge circuit is directly connected with the secondary side of the transformer. The first capacitor is located between the second full-bridge circuit and the second direct current end and is connected with positive and negative poles of the second direct current end. The bidirectional DCDC circuit provided in the application uses leakage inductance of the primary side of the transformer and the first capacitor to form an LC resonant circuit instead of an LC resonant circuit arranged at two ends of the transformer, so that the function of the resonant circuit is realized while the number and volume of electrical elements of a topological structure are reduced, thereby reducing the cost.

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.

The utility model discloses a universal conversion device for converting an LVDS (Low Voltage Differential Signaling) input signal into a V-By-One output signal, which comprises an LVDS input interface, a master control conversion chip, a V-By-One output interface, an NS / JEIDA configuration, a partition selection configuration, a direct current-direct current circuit, a nonvolatile memory chip and an expansion power supply head, the main control conversion chip is electrically connected with the LVDS input interface and receives a 2-port LVDS signal, the main control conversion chip outputs an 8-Lane V-By-One signal, the V-By-One output interface is electrically connected with the main control conversion chip and receives the 8-Lane V-By-One signal, and the NS / JEIDA configuration is electrically connected to the main control conversion chip.

The invention discloses a power transmission line induction power taking system and a self-adaptive variable step size maximum power tracking method. The power taking system comprises a CT type induction power taking unit, the CT type induction power taking unit is connected with a rectification circuit, the rectification circuit is connected with a filter circuit, and the filter circuit is connected with a DC-DC circuit. The power taking system further comprises an MOS tube arranged on the rectification side, the MOS tube serves as a bypass switch and is connected with the controller, and the controller is connected with the voltage and current sampling circuit and the load. When the output power needs to be reduced, the MOS is conducted. The controller controls the work of each module and monitors sampling signals of voltage and current in real time. If the output voltage exceeds the discharge voltage, the bypass switch MOS tube needs to be controlled to be conducted, and when the current of the power transmission line is low, power can be taken at the maximum power. The maximum power tracking algorithm realizes dynamic stability of the power under the condition that the voltage and the current are stable. The automatic adjustment step length is designed based on the self-adaptive variable step length perturbation and observation method, and the maximum power point can be tracked at a high speed and with high precision.

This application provides an uninterruptible power supply (UPS), an uninterruptible power supply control method, a related apparatus, and a system. In one example, the UPS determines a target value of a SOC of a battery of the UPS; and controls, based on the determined target value, a rectifier circuit and a direct current-to-direct current circuit in the UPS to charge the battery to make the SOC of the battery equal to the target value, or controls, based on the determined target value, an inverter circuit and a direct current-to-direct current circuit in the UPS to discharge the battery to make the SOC of the battery equal to the target value.

Some embodiments provide a DC solid state protection device that includes a capacitor configured such that in the event of a short-circuit condition, the capacitor provides all the short-circuit current required for the solid state protection device to detect a current indicative of a short-circuit condition and to cause a solid state switch to be opened, thereby tripping the solid state protection device.

The positive and negative current overcurrent protection self-locking circuit comprises a power supply circuit, a positive and negative current detection circuit, a positive current comparison circuit, a negative current comparison circuit, a level self-locking circuit, an overcurrent reset circuit and a control output circuit, one end of the positive current comparison circuit and one end of the negative current comparison circuit are respectively connected with the positive and negative current detection circuit, the other end of the positive current comparison circuit and the other end of the negative current comparison circuit are respectively connected with the level self-locking circuit and the overcurrent reset circuit, and the overcurrent reset circuit is further connected with the level self-locking circuit. The level self-locking circuit is connected with the control output circuit; the power supply circuit is connected with the positive and negative current detection circuit, the positive current comparison circuit, the negative current comparison circuit, the level self-locking circuit, the overcurrent reset circuit and the control output circuit. By adopting the over-current protection circuit, accurate and reliable over-current protection can be provided for a direct-current circuit.

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.

The invention relates to the technical field of distribution boxes, and discloses an AC / DC intelligent distribution box, which comprises a box body, an upper flip cover hinged to the front side of the box body and an AC distribution module arranged in the box body, and also comprises a DC distribution module comprising a rectifier module and a main transformer arranged in the box body, the main transformer is respectively connected with a plurality of direct-current circuit breakers arranged in the box body through direct-current power transmission lines, branch transformers corresponding to the direct-current circuit breakers are arranged in the box body, alternating current is converted into direct current through a rectifier module after passing through a main power switch of the alternating-current power distribution module, and then voltage regulation is carried out through the main transformer; a temperature control heat dissipation module and a self-soot-blowing top cover; the self-soot-blowing top cover is arranged at the top of the box body, and soot blowing cleaning is carried out through the temperature control heat dissipation module; compared with the prior art, the power connection socket has the advantages that an alternating current power supply and a direct current power supply are provided for the power connection socket at the same time, and dust falling on the top can be automatically cleaned.

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 provides a mainboard test system, which comprises an external device, a PC mainboard, a backlight power supply circuit and an AC-to-DC circuit, and the external device comprises a storage board or a control device. The PC mainboard is electrically connected with external equipment, the control end of the backlight power supply circuit and the control end of the AC-to-DC circuit, the input end of the AC-to-DC circuit is electrically connected with an AC power supply, the first output end of the AC-to-DC circuit is electrically connected with the input end of the backlight power supply circuit, and the output end of the backlight power supply circuit is electrically connected with a display screen. In the test system, the PC mainboard, the backlight power supply circuit and the AC-to-DC circuit can be tested without the participation of a display screen, so that the test cost is reduced.

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.

The application describes a method for detecting an arc (50) in a DC circuit, comprising the steps: - operating a DC / DC converter (21, 22) of a two-stage inverter (10) in a first operating mode (BM1) with a first intermediate circuit voltage (UZWK,1) applied to a DC intermediate circuit (31), - checking values ​​of current and / or voltage assigned to a DC connection (11, 12) of the inverter (10) for the presence of an indication of an arc (50) in the first operating mode (BM1) of the DC / DC converter (21, 22), wherein, when the values ​​of current and / or voltage indicate an arc (50), the DC / DC converter (21, 22) is operated in a second operating mode (BM2) with a second intermediate circuit voltage (UZWK,2) which is greater than the first intermediate circuit voltage (UZWK,1) and which is greater than or equal to the open circuit voltage (ULL) of the DC source (60), and wherein the following is carried out in the second operating mode (BM2): - Deactivating the DC / DC converter (21, 22) connected to the DC terminal (11, 12) in the second operating mode (BM2) of the DC / DC converter (21, 22).

The utility model discloses a direct-current monitoring device for an open-loop direct-current circuit of a distributed energy station, and the open-loop direct-current circuit of the distributed energy station comprises two 220V direct-current circuit branches, and the two 220V direct-current circuits pass through a direct-current power distribution room and a high-voltage power distribution room and are connected to a small bus at the top of a screen for power supply. The two 220V direct current circuits are respectively provided with an upper-level switch and a lower-level switch; the system also comprises a monitoring module which is connected with the two 220V DC circuit branches. The monitoring module is used for monitoring a DC load. The superior switch and the subordinate switch in the same branch are in interlocking control through a switch auxiliary contact; a locking unit of the monitoring module adopts different branch subordinate switch opening AND gate logic as a locking condition for judging closing behaviors of different branch subordinate switches. According to the utility model, automatic switching can be realized when the screen top miniature bus loses power, the overall operation condition of associated equipment can be checked in real time, and faults can be found in time.

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.