338 results about "Conduction mode" patented technology

A power converter incorporating a synchronous rectifier implements adaptive gate voltage regulation for fast turn-off of the synchronous rectifier. In some embodiments, the adaptive gate voltage regulation circuit and method monitors the slope of the synchronous rectifier current during the on period of the synchronous rectifier. In response to detecting the synchronous rectifier current decreasing rapidly, a larger gate discharge current is applied to quickly discharge the synchronous rectifier gate voltage. In response to detecting the synchronous rectifier current decreasing more moderately, a smaller gate discharge current is applied to discharge the synchronous rectifier gate voltage in a moderate manner. When the synchronous rectifier can be turned off quickly, large reverse current and large drain voltage spike at the synchronous rectifier is avoided. The adaptive gate voltage regulation circuit and method is particularly useful when the power converter is operated in the discontinuous conduction mode.

The invention belongs to the technical field of power distribution, and discloses a direct current transformer soft switch and a control method.The direct current transformer soft switch comprises a medium-voltage direct current bus and low-voltage direct current buses, the medium-voltage direct current bus is electrically connected with a modular multi-level multi-port direct current converter, and the modular multi-level multi-port direct current converter is electrically connected with a plurality of low-voltage direct current converters; the plurality of low-voltage direct-current converters are electrically connected with a low-voltage direct-current bus and are used for realizing bidirectional power transmission from medium-voltage direct current to low-voltage direct current; according to the method, the medium-voltage side inductance value is reduced, the medium-voltage side current ripple is enabled to pass zero, the M3DC operates in an approximate critical conduction mode, a constant valley current control strategy is adopted, the minimum value of the medium-voltage side inductance current is controlled to be constant under different working conditions, and then zero-voltage switching-on of a switching device in a wide operation range and zero-current switching-off of an anti-parallel diode are achieved.

A method of operating a PFC circuit. The method includes receiving an input voltage at an input terminal, controlling a current in an inductor via a first switch having a drain terminal, a source terminal and a gate terminal, where the inductor is coupled between the input terminal and the drain terminal and where during an on-time of the first switch the current in the inductor increases from substantially zero to a peak, during a first off-time of the first switch the current in the inductor decreases from the peak to substantially zero, and during a second off-time of the first switch the current in the inductor is substantially zero, generating a first reference voltage that is inversely proportional to a sum of the on-time and the first off-time of the first switch, and controlling the on-time of the first switch in response to the first reference voltage.

A system may include a multi-level power converter comprising a power inductor and a plurality of switches and a controller configured to control the plurality of switches such that the multi-level power converter generates a regulated output voltage from an input voltage to the multi-level power converter, monitor an average inductor current through the power inductor, and operate the multi-level power converter in one of a continuous conduction mode and a discontinuous conduction mode based on the average inductor current.

The utility model provides a liquid cooling assembly, a battery module and a battery pack. The liquid cooling assembly comprises a heat exchange unit and a connecting pipe set, the heat exchange unit comprises a plurality of heat exchange parts arranged at intervals in the X direction, a cylindrical battery column is installed between every two adjacent heat exchange parts, each heat exchange part is used for being connected with the cylindrical battery column in a heat conduction mode, each heat exchange part is provided with a conveying flow channel, and each conveying flow channel is provided with a liquid inlet and a liquid outlet; the connecting pipe set comprises a liquid inlet branch pipe and a liquid outlet branch pipe, the liquid inlet branch pipe sequentially communicates with the multiple liquid inlets, an inlet allowing cooling liquid to flow in is formed in the liquid inlet branch pipe, the inlet is far away from the two heat exchange parts located on the edge in the multiple heat exchange parts, and the liquid outlet branch pipe sequentially communicates with the multiple liquid outlets. And an outlet through which the cooling liquid flows out is formed in one end of the liquid outlet branch pipe, so that the pressure drop difference caused by the length difference of pipelines can be reduced, enough cooling liquid flow can be ensured to be obtained by each heat exchange part, and the uniformity of cooling liquid flow conveying is improved.

The invention discloses a switching power supply circuit and a power supply chip, and relates to the technical field of switching power supply chips, the switching power supply circuit is provided with a continuous conduction mode and an intermittent conduction mode, the switching power supply circuit comprises a switching circuit, the input end of the switching circuit is used for accessing an external power supply, and the output end of the switching circuit is used for accessing an external load; the switch control driving circuit is electrically connected with the controlled end of the switch circuit, the switch control driving circuit is used for controlling the switch circuit to work, and in the continuous conduction mode, the first feedback loop starts to work, generates a charging signal according to the first voltage signal, and outputs the charging signal to the switch control driving circuit to control the switch circuit to work; and in the interrupted conduction mode, the second feedback loop is started to work, generates a charging signal according to the second voltage signal, and outputs the charging signal to the switch control driving circuit to control the switch circuit to work, so that the problem of excessive working loops of the adaptive switching power supply chip detection loop can be reduced, and the power consumption of the chip is effectively reduced.

The invention discloses a zero-voltage turn-on circuit and a zero-voltage turn-on method of a switching tube in a switching power supply, and belongs to the technical field of circuits. In a critical conduction mode, when a low-side power tube is turned off, the rising edge zero-voltage starting circuit compares a switch node voltage with an input voltage or compares the switch node voltage with an output voltage under the control of a low-side gate driving voltage, outputs a high level to a high-side gate driving end when the switch node voltage is equal to the input voltage or the output voltage, and outputs a low level to a low-side gate driving end when the high level is equal to the output voltage. A high-side power tube is controlled through a high level to realize zero-voltage starting; in a critical conduction mode, when the high-side power tube is turned off, the falling-edge zero-voltage starting circuit compares an induced voltage with a pull-up resistor voltage under the control of a high-side gate driving voltage, outputs a high level to a low-side gate driving end when the induced voltage is equal to the pull-up resistor voltage, and controls the low-side power tube to realize zero-voltage starting through the high level. The induced voltage is equal to the sum of the pull-up resistor voltage and the switch node voltage. According to the invention, the transmission delay can be reduced.

The invention discloses a drive control circuit for large-scale optical switch signal switching. Control drive design on a silicon photon optical switch array is achieved through hardware model selection and circuit design, FPGA logic design and upper computer control optimization. The circuit comprises an overvoltage / anti-reverse connection protection circuit, an FPGA driving power supply circuit, an HV high-voltage conversion circuit, a feedback voltage regulation circuit, a high-voltage driving circuit and FPGA conduction logic. According to the invention, channel conduction data is generated by using a PC and upper computer software, so that a programmable modified optical switch conduction mode is realized, optical signal adjustable mode switching is realized, and signal low-loss interaction of a signal switching center is satisfied. Micromechanical voltage is adopted to drive the optical switch unit, and the problems that a traditional thermo-optical switch is high in power requirement, serious in heat dissipation requirement and the like can be solved; and the expansion capability limitation of high-voltage signals is solved through the serial-parallel conversion voltage driving module, and the function of driving the large-scale optical switching switch array is realized.

A switch control method is applied to a hybrid voltage converter including a switched capacitor unit and a freewheeling unit. The method including obtaining the output current of the hybrid voltage converter, when the output current is greater than a first current threshold, controlling the switches in the hybrid voltage converter to operate in parallel conduction mode, when the output current is less than the first current threshold, controlling the switches in the hybrid voltage converter to operate in sequential conduction mode. When the switches operate in parallel conduction mode, N switches in the switched capacitor unit are controlled to turn on and off with the same duty cycle and a phase shift of 360 / N degrees. When the switches operate in sequential conduction mode, each switch in the switched capacitor unit is controlled to conduct individually with the same duty cycle in sequence.

According to the frequency jittering method and circuit and the quasi-resonant flyback converter applying the same, when the quasi-resonant flyback converter works in an intermittent conduction mode, frequency jittering is carried out in the following mode that in an Mth switching period group, after the system working frequency reaches a frequency limiting line, a main switching tube is controlled to be conducted at the valley bottom after an ith zero-crossing signal is detected; in the Nth switching period group, when the working frequency of the system reaches a frequency limiting line, the main switching tube is controlled to be switched on at the valley bottom after the jth zero-crossing signal is detected; wherein M and N are two adjacent switching period groups; i is not equal to j. Through the above arrangement, when the quasi-resonant flyback converter is in an intermittent conduction mode, the two adjacent switching period groups control the conduction of the main switching tube at two different valley bottoms, the frequency spectrum of EMI can be effectively dispersed, the function of optimizing EMI is realized, and compared with a mode of jittering peak current or jittering working frequency in the prior art, the frequency spectrum of the quasi-resonant flyback converter is greatly improved. And a better EMI optimization effect is achieved.

A power factor correction (PFC) control circuit includes a pulse-width modulation (PWM) circuit configured to control a switch of a switching power converter. The PFC control circuit further includes a mode control circuit configured to select a conduction mode from a plurality of conduction modes for the switching power converter based at least in part on an output power of the switching power converter and to control a beginning of a switching cycle of the switching power converter based on the selected conduction mode. In addition, the PFC control circuit includes a current regulation circuit configured to provide a regulation signal to the PWM circuit to regulate an average coil current of the switching power converter in each of the plurality of conduction modes.

A method for charging a battery pack via an offboard energy source uses an interleaved boost converter and closed-loop control. The energy source outputs a charging current via a DC charge port during a direct current fast-charging (DCFC) process. A controller detects a voltage disparity condition in which a voltage capability of the battery pack exceeds a voltage capability of the energy source. In response to this condition, a rise of the charging current over time is recorded as a current trajectory and an open-loop equivalent time constant is extracted from the current trajectory. A time constant of the PI control block is set substantially equal to the equivalent time constant. The PIM is controlled in closed-loop using proportional-integral control. The charging current is controlled in a continuous current conduction mode during the DCFC process.

A power converter incorporating a synchronous rectifier implements adaptive turn-off voltage control for fast turn-off of the synchronous rectifier in the continuous conduction mode. In some embodiments, the synchronous rectifier turn off detection threshold is adaptively changed as a function of the detected operation mode of the power converter. In response to detecting the power converter being operated in the continuous conduction mode, the synchronous rectifier turn off detection threshold is set to a voltage value farther away from zero volt as compared to the nominal turn off detection threshold. In this manner, the synchronous rectifier can be turned off earlier while in the continuous conduction mode. When the synchronous rectifier can be turned off quickly, large reverse current or negative current as well as large drain voltage spike at the synchronous rectifier can be avoided. The reliability of the synchronous rectifier and the power converter is improved.

A power converter includes a plurality of power stages configured to generate an output current that has an output voltage based on an input current that as an input voltage a control circuit coupled to the plurality of power stages. The control circuit is configured to control operation of the plurality of power stages. The control circuit includes a plurality of constant-on-time loops for the plurality of power stages. The power converter is configured to operate in a single-phase mode or a multiphase mode. A first power stage of the plurality of power stages supports a continuous conduction mode and a discontinuous conduction mode when the power converter operates in the single-phase mode.

The invention belongs to the technical field of electrical equipment, and discloses an isolating switch and switch equipment, the isolating switch comprises a static contact seat, a static contact, a moving contact seat and a moving contact, and the moving contact can slide in the moving contact seat in a reciprocating manner so as to be matched with the static contact to realize opening and closing; a hollow air cavity is formed in the end portion of the moving contact, an air guide hole is formed in the end portion of the air cavity and communicated with the air cavity, and a heat conduction piece is further arranged in the air cavity and connected with the moving contact in a heat conduction mode. When the moving contact is separated from the static contact, an electric arc is generated, heat energy released by the electric arc is conducted into the air cavity through the moving contact and the heat conduction piece, insulating gas in the air cavity is heated and expanded, air pressure in the air cavity is increased, and the gas is jetted out along the gas guide hole under the action of high pressure and quickly blown to the root of the electric arc. And the arc extinguishing performance of the isolating switch is improved, so that the isolating switch obtains shorter arcing time, the contacts are prevented from being ablated by the arc, and the insulation performance of the isolating switch is prevented from being reduced too fast.

The embodiment of the invention discloses a direct-current pulse power supply, a control method and semiconductor process equipment, a controller responds to a direct-current output instruction, the working mode of a first switch is controlled to be a conduction mode, and the working modes of a second switch and a third switch are controlled to be a disconnection mode, so that the negative electrode of the direct-current power supply is conducted with a second output port; therefore, the direct-current pulse power supply is in a direct-current output mode. And controlling the working modes of the first switch to the third switch to be switched between a first control state and a second control state through the controller in response to the pulse output instruction, so that the negative electrode of the direct-current power supply and the positive electrode of the bias power supply are alternately conducted with the second output port, and the direct-current pulse power supply is in a pulse output mode. On the basis, the direct-current pulse power supply can be compatible with a direct-current output mode and a pulse output mode, so that the utilization rate of equipment can be improved, and the cost and the site area can be reduced.

The invention relates to a resonant converter, which comprises a primary side switch circuit; the resonant cavity comprises a transformer, a primary winding and a secondary winding, and the primary winding is electrically connected to the primary switching circuit; the secondary side switching circuit is electrically connected to the secondary side winding and comprises a first switching bridge arm and a second switching bridge arm, and a phase shift angle exists between the first switching bridge arm and the second switching bridge arm; wherein secondary side current flowing through the secondary side winding selectively works in a forced continuous conduction mode, a continuous conduction mode or a critical conduction mode according to the operation of the primary side switching circuit and the secondary side switching circuit; and the control circuit is used for adjusting the switching frequency and the phase shift angle of the primary side switching circuit and the secondary side switching circuit when the secondary side current flowing through the secondary side winding works in a forced continuous conduction mode or a continuous conduction mode, so that the secondary side current flowing through the secondary side winding is gradually adjusted to work in a critical conduction mode. And the actual voltage gain value of the resonant converter is controlled at the default voltage gain value.

The invention relates to the technical field of new energy, in particular to a signal acquisition assembly and an installation method thereof, a battery module and a battery system. The signal acquisition assembly comprises a PCB which comprises a third surface along one side of the thickness direction of the PCB, and a first bonding pad, a second bonding pad and a third bonding pad which are separated from each other; the first bonding pad is used for welding a voltage acquisition line, and the second bonding pad and the third bonding pad are used for welding a temperature acquisition line; the temperature sensor is installed on the PCB in a heat conduction mode and electrically connected between the second bonding pad and the third bonding pad in series; and the conducting strip comprises a first part and a second part, the first part is fixed on the PCB and is electrically connected with the first bonding pad, the second part is used for being welded on a conducting bar electrically connected with an electrode terminal of the battery monomer, the conducting bar is combined with the battery monomer in a heat conduction manner, and the conducting bar is provided with a first surface for the third surface to be attached and contacted.

The utility model discloses a deicing device which is used for deicing a battery replacing vehicle, a battery pack of the battery replacing vehicle is installed at the bottom of a vehicle body through a locking mechanism so that quick replacement of the battery pack can be achieved, the deicing device comprises a movable vehicle body and an electromagnetic heating unit installed on the vehicle body, and the electromagnetic heating unit can generate an alternating electromagnetic field on the periphery of the electromagnetic heating unit; the machine body can move to the bottom of a vehicle body of the battery changing vehicle and enables the bottom of the vehicle body and / or the locking mechanism to be heated under the action of the alternating electromagnetic field of the electromagnetic heating unit so as to conduct deicing operation on the bottom of the vehicle body and / or the locking mechanism. Heat for hot melting of the ice layer comes from heat energy generated by the locking mechanism and / or the vehicle body, and the heat energy is transmitted into the ice layer in a direct contact solid conduction mode, so that the transmission loss of the heat energy from the locking mechanism and / or the vehicle body to the ice layer is greatly reduced, the ice layer receives the heat from the locking mechanism and / or the vehicle body to a large extent, and the service life of the ice layer is prolonged. And the ice melting efficiency is greatly improved.

The invention relates to an operation mode control technique for a power factor correction circuit. A power factor correction (PFC) control circuit includes a pulse width modulation (PWM) circuit configured to control a switch that switches a power converter. The PFC control circuit also includes a mode control circuit configured to select a conduction mode from a plurality of conduction modes for the switching power converter based at least in part on an output power of the switching power converter, and controlling a start of a switching cycle of the switching power converter based on the selected conduction mode. Further, the PFC control circuit includes a current regulation circuit configured to provide a regulation signal to the PWM circuit to regulate an average coil current of the switching power converter in each of the plurality of conduction modes.

The invention discloses a spreader control hydraulic circuit, a reachstacker hydraulic control system and a reachstacker, belonging to the technical field of reachstackers. The spreader control hydraulic circuit includes a leveling cylinder, a leveling valve group and an oil supply port P1; the leveling valve group includes a first leveling valve, a second leveling valve and a reversing control valve; when the first leveling valve and the second leveling valve are simultaneously conducted, the spreader performs adaptive leveling under the action of gravity; the reversing control valve is provided with a first conduction mode and a second conduction mode; by switching the first conduction mode and the second conduction mode through the reversing control valve, the tilting direction of the spreader is switched. The invention can enable the spreader to perform adaptive leveling and switch the tilting direction of the spreader, reducing the lifting difficulty.

The invention discloses a multi-mode switching control method suitable for a grid-connected isolation inverter, and the method comprises the steps: in each half power grid voltage period, according to a power grid instantaneous voltage phase Theta g outputted by a phase-locked loop in the isolation inverter, the phase Theta g is within [0, pi], then the phase Theta g is compared with given power grid voltage phases Theta g1 and Theta g2, the Theta g1 and Theta g2 meet the condition that Theta g1 is smaller than or equal to Theta g2, and the Theta g1 is smaller than or equal to Theta g2; a variable-frequency discontinuous conduction mode, namely a variable-frequency DCM mode, is adopted in the ranges of 0 < theta g < theta g 1 and pi-theta g 2 < theta g < pi, a main switching tube of a flyback converter in the isolation inverter is controlled to be switched on when the period is larger than a given switching period and the drain-source voltage valley value, and a critical conduction mode, namely a BCM mode, is adopted in the range of theta g 1 < theta g < pi-theta g 2. And controlling a main switch tube of the flyback converter to be switched on at the drain-source voltage valley value. Different working modes are adopted under different output voltages, so that the switching loss of the isolation inverter in a full-load range is reduced, and the energy conversion efficiency of the isolation inverter is greatly improved.

The invention relates to the technical field of soil temperature increasing test simulation, and provides a field soil temperature increasing simulation device and method.The device comprises a heating pipe used for increasing temperature of soil in a simulation area, the heating pipe comprises a plurality of sections, the sections are laid in the simulation area in a layered mode according to the soil depth, and the heating pipe is used for heating the soil in the simulation area; the subsections in each layer are continuously and uniformly laid; the heating pipe comprises an insulating pipe and an electric heating wire penetrating through the insulating pipe; the power supply assembly is used for supplying power to the electric heating wire under the condition that the insulating tube is filled with the liquid, and the electric heating wire heats the liquid in the insulating tube under the condition that the electric heating wire is electrified; and the temperature controller is used for controlling the heating temperature of the heating pipe. According to the soil temperature increasing device, soil temperature increasing is achieved in a layered arrangement and heat conduction mode, soil disturbance is small, meanwhile, the temperature increasing mode is mild and stable, vegetation damage is avoided, the influence on the experimental result of soil temperature increasing simulation is reduced, and the accuracy of the experimental result is ensured.

The invention discloses a switching converter and a control circuit and a control method thereof. The switching converter comprises a main control tube and a synchronous tube and converts an input voltage into an output voltage, and the control circuit comprises a compensation circuit which generates a compensation signal representing a first duration based on an oscillation period of voltages at two ends of the synchronous tube, the input voltage and the output voltage; the synchronous tube control circuit generates a synchronous tube control signal based on the compensation signal to control the synchronous tube; wherein when the switching converter works in an intermittent conduction mode and the inductive current of the switching converter is reduced to zero, the synchronous tube is switched off, and after the synchronous tube is switched off and delayed for a first time length, the synchronous tube is switched on again for a first time length; and when the switching converter works in the critical conduction mode, the synchronous tube is switched off after the inductive current is reduced to zero and a first duration. According to the control circuit, zero-voltage conduction of the switching tube is realized, and the switching loss is reduced.

The invention discloses a trapezoidal wave current soft switching method of an interleaving DC-DC converter, which is used for a two-phase interleaving bidirectional DC-DC converter based on a coupling inductor and a multi-phase interleaving converter thereof, and is characterized in that an inductive current adopts a trapezoidal wave mode, so that the converter works in an approximate critical conduction mode; a fixed switching frequency control or hybrid control method is adopted, so that the device can work in a Buck mode and can also work in a Boost mode. The method for realizing the soft switching is characterized in that the parasitic capacitance or the external resonant capacitor of the switching tube is discharged to be zero under the resonance action of the inductor and the capacitor in the dead zone time when the upper bridge arm switch and the lower bridge arm switch are alternately switched on, so that the zero-voltage switching-on of all the switching tubes is realized. And each phase current sharing control is adopted in the multi-phase interleaving parallel topological structure. According to the invention, the problems of large current peak value and high turn-off loss of a traditional triangular wave current mode are solved, the output ripple current is reduced, a soft switching method is provided, the switching loss is reduced, and the conversion efficiency of the converter is improved.

The invention provides a power battery system, a series-parallel connection control method, a movable carrier and a storage medium, and relates to the technical field of power batteries, the system comprises a control module, a switch module and N battery packs; the switch module is electrically connected with the control module and each battery pack respectively; the control module is used for responding to the charging and discharging control strategy and sending a series-parallel connection control signal to the switch module, and the series-parallel connection control signal comprises a series connection signal, a parallel connection signal or a series-parallel connection signal; and the switch module is used for entering a target conduction mode according to the control signal, so that the battery packs are connected according to a target connection mode, and the target connection mode comprises a series connection mode, a parallel connection mode or a series-parallel connection mode. The compatibility of the power battery system is improved by controlling the series-parallel connection mode of the battery packs in the power battery system.

The utility model discloses an unattended crude oil handover metering system, which is characterized in that a first density totalizer is arranged on the basis of a traditional dynamic handover system to detect the density of crude oil on line, and the first density totalizer adopts metering equipment for measuring the density of the crude oil on line by using electrical characteristics; crude oil density can be mutually verified through a capacitance mode and an electric conduction mode, the accuracy of crude oil density detection is improved, compared with other density metering equipment, the measured density error is small, and a parameter verification assembly is arranged on the basis of a traditional dynamic handover system. A second flow meter, a second temperature transmitter, a second pressure transmitter, a second water content meter and a second density integrating instrument are arranged on the verification pipeline, the front end of the verification pipeline is connected with a calibration crude oil tank through an oil supply pipe, calibrated crude oil is adopted, it can be avoided that metering devices of the same kind go wrong at the same time, and the accuracy of the verification process is guaranteed.

The invention provides a new energy forklift battery capable of preventing local high temperature, and relates to the technical field of forklift batteries, the new energy forklift battery comprises an upper base and a lower base, a battery cell is arranged between the upper base and the lower base, and the upper end of the upper base is provided with a refrigeration wafer and an alloy cooling fin; a heat conduction piece is arranged between every two adjacent columns of battery cells; the heat conduction part comprises alloy heat dissipation boxes and superconducting refrigeration plates, each alloy heat dissipation box is located between the two columns of battery cells, the upper end of each alloy heat dissipation box is connected with an alloy heat dissipation sheet, and at least six superconducting refrigeration plates are elastically and movably arranged on the two sides of each alloy heat dissipation sheet respectively; and the outer side of the superconductive refrigeration plate is propped against the outer surface of the battery cell. The superconducting refrigeration plate is in close contact with the battery cells, heat generated by the battery cells can be directly transmitted out in a heat conduction mode, heat generated by each battery cell can be effectively and evenly diffused, and therefore the service life of the battery cells is prolonged, and the safety of the battery cells is improved.

The invention relates to a switched mode power supply (SMPS). A switched mode power supply includes: a first switch coupling a first node receiving a supply voltage to a second node supplying an output voltage; and a second switch coupling a third node receiving the reference voltage to the second node. The comparator is used for comparing the output voltage with the comparison voltage. When the switched mode power supply is operating in the pulse skipping mode, the comparator generates an output signal indicating that the output voltage is higher than the comparison voltage during a portion of the on phase of the first switch. Once the output voltage is below the comparison voltage, the switched mode power supply transitions from the pulse skip mode to the continuous conduction mode.

The invention provides a vehicle with a welded bus bar connector. In a high voltage vehicle electronic system, an electronic component having a tab is welded to a bus bar using pulsed laser welding. Each tab is welded to the bus bar by an array of welds. Each spot welding portion includes an inner region formed in a pinhole mode by laser welding and an outer region formed in a conduction mode by laser welding. The density of energy applied to the inner region is between ten and twenty times higher than the density of energy applied to the outer region.