16005results about "Dc-dc conversion" patented technology

A solid-state transformer is provided. The solid-state transformer includes a first stage, a first DC bus and a second stage. The first stage is configured to receive an AC power and convert the AC power into a first DC power. The first DC bus is electrically connected to the first DC power. The second stage is electrically connected to the first stage through the first DC bus, and is configured to perform isolated step-down DC / DC conversion on the first DC power to generate a second DC power. The first stage is configured to operate at a modulation index higher than 1, and the modulation index is defined by a ratio of twice AC voltage provided by the AC power to voltage across the first DC bus.

The invention relates to the technical field of power electronics, and discloses a soft switch of a high-frequency switch transformer and a distributed control method and system thereof, and the method comprises the steps: achieving the precise synchronization of nodes through the construction of a ring topology network, combining the monitoring of multiple physical quantities with the collaborative optimization of parameters, dynamically adjusting the parameters of a resonant network and a driving time sequence, and achieving the precise synchronization of the nodes. A zero-voltage switching state is maintained, and electromagnetic interference is suppressed by adopting the composite optimization model; the system comprises a network initialization module, a multi-physical-quantity monitoring module, a space-time synchronization control module, a resonance parameter adjustment module, an electromagnetic optimization decision module, a dynamic adjustment module and a parameter evolution module. The stability of the soft switch is improved through a distributed network and time-space synchronization, and the loss is reduced by adopting a dynamic optimization algorithm; constructing an electromagnetic interference optimization model to enhance compatibility; performing multi-parameter fusion and weight distribution to optimize dynamic response; the reliability is improved through a high-precision protocol and coevolution; and the tensor product framework realizes multi-dimensional intelligent cooperative control.

The invention provides a COT step-down converter comprising an inductive current detection circuit configured to detect an inductive current flowing through an inductor connected to a system output of an output voltage of an output system of the COT step-down converter, and generate a current zero-crossing detection signal indicating whether the inductive current crosses zero, the inductive current zero-crossing means that the inductive current is changed from positive current to negative current; and a sleep mode control circuit configured to generate a sleep mode control signal for controlling one or more circuit modules in the COT buck converter to change from an operating state to a closed state based on the current zero-crossing detection signal, an output feedback voltage representing a system output voltage of the COT buck converter, and a predetermined reference voltage.

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 invention discloses a driving control method of a DAB converter and related equipment, and relates to the technical field of power electronic converter control, and the method comprises the steps: calculating a voltage transformation ratio based on an input voltage and an output voltage through a current stress adjustment module, and calculating an output power based on the output voltage and an output current, substituting the voltage transformation ratio and the output power into a current stress adaptive minimization algorithm to solve an internal phase shift angle; meanwhile, through a PI controller, an external shift phase angle is adjusted based on a difference value between the instruction voltage and the output voltage; outputting the inner phase shift angle and the outer phase shift angle to a PWM modulation generator to generate a switching tube driving signal; the DAB converter is controlled by the driving signal to realize rated voltage output and current stress minimization, so that the efficiency and reliability of the converter are improved.

The invention relates to a PFC-PWM (Pulse Width Modulation) dual-mode control method for a high-voltage direct-current power supply with a wide output voltage range. The output current of the high-voltage direct-current power supply is detected in real time, the critical threshold value of the load impedance is mapped into the hysteresis interval of the output current, the theoretical boundary of mode switching is obtained, and the control mode is dynamically adjusted. In order to further guarantee smooth switching of the two control modes, hysteresis control logic is designed, and undisturbed smooth switching of the PFM mode and the PWM mode is achieved. Based on an energy equivalence principle and a frequency consistency constraint of a critical load SWL working point, a current threshold criterion and a parameter pre-synchronization strategy are constructed, seamless connection of a mode switching process in a frequency domain and an energy domain is ensured, a transient oscillation risk is remarkably reduced, and a guarantee is provided for continuous and stable output of a full-range load working condition.

The invention belongs to the technical field of power supply management, and particularly relates to a high-precision DCDC power supply voltage stabilization calibration system and method, which comprises a DCDC power conversion module, a traditional feedback control module, a high-frequency ripple sampling and digitization module, a dynamic load prediction module, a feedforward compensation generation module and a calibration management module, through high-frequency ripple sampling and digital output of ripple signals, real-time spectrum analysis is carried out to predict load transient changes, prospective compensation signals are generated, and traditional feedback control is combined to finely adjust PWM signals of the DCDC module. According to the scheme, feedback lag is overcome, transient overshoot / undershoot of voltage is remarkably restrained, the dynamic voltage stabilization error is controlled within + / -0.3%, and high-precision voltage stabilization under both static and dynamic working conditions is achieved.

The invention discloses a low-output-ripple automatic-current-sharing interleaving buck converter and a control method thereof.The converter comprises a main power circuit and an auxiliary compensation circuit, and the main power circuit adopts two interleaving main branches to achieve voltage conversion and energy transmission; automatic current sharing of the circuit is realized through the integrated network switch module and PWM signal control; the auxiliary compensation circuit adopts a current mirror image compensation principle, and adjusts the magnitude of the compensation current by comparing the difference between the output current of the main power circuit and the reference current, so as to effectively suppress the output current ripple; the control method comprises the steps of output voltage monitoring, PI adjustment, duty ratio modulation and a complementary control mechanism, current ripple phase offset is ensured, and the system stability and efficiency are improved. Compared with the prior art, the method has the advantages that the complexity of a control system is reduced, the working efficiency is improved, the current ripples are effectively eliminated, and the method has relatively high practical value and popularization prospect.

Provided in the present application are a balanced charging method and apparatus for a battery pack, and a computer program product. Charging current control consists of two stages, i.e., a "pulse square-wave excitation" stage and a "multi-stage current-reduction charging" stage. During the pulse square-wave excitation stage, the parameter identification of an equivalent circuit model and the joint estimation of state variables are realized, thereby providing reliable battery parameters for a subsequent balancing process. During the multi-stage current-reduction charging stage, a flyback converter is used to control a balanced current of each battery cell, and the battery cells remain in a charging state throughout a balancing process, thereby effectively mitigating the impact of a hysteresis voltage.

The invention provides a circulation power optimization method and system for a three-phase dual-active bridge, and relates to the field of power electronics, the method comprises the following steps: determining an optimal backflow modulation strategy set corresponding to a hybrid modulation group, the hybrid modulation group comprising triangular wave modulation, trapezoidal modulation, synchronous modulation and extended phase shift modulation, the optimal backflow modulation strategy set corresponding to the hybrid modulation group comprises modulation modes and degree-of-freedom relationships corresponding to different transmission power per unit value ranges in different voltage conversion ratio ranges; determining a degree of freedom and power relationship set corresponding to the hybrid modulation group, wherein the relationship set comprises a relationship between the degree of freedom and power of different transmission power per unit values corresponding to each mode; the phase shift angle, the primary side duty ratio and the secondary side duty ratio are determined by combining the real-time voltage conversion ratio and the real-time virtual power per unit value, operation of the three-phase dual-active bridge is controlled, and the method has the advantages of reducing complexity and improving portability and efficiency.

A power management circuit is disclosed that includes a boost converter, a pass transistor, and an overcurrent detect circuit. The boost converter is configured to convert an input voltage into a first power supply voltage. The pass transistor is configured to transfer the first power supply voltage as a second power supply voltage after a predetermined time from a time point at which the first power supply voltage is activated. The overcurrent detect circuit is configured to perform an overcurrent detect operation by sensing a current flowing through the pass transistor. A display device is also disclosed that includes the power management circuit.

The invention discloses an intelligent silicon controlled rectifier voltage conversion circuit, which relates to the technical field of voltage conversion, and comprises a photovoltaic module, a micro-control module, a power regulation module, a first voltage threshold, a second voltage threshold, a second voltage threshold, a third voltage threshold, a fourth voltage threshold, a fifth voltage threshold and a sixth voltage threshold, when the converted electric energy is larger than a first voltage threshold value, the access control module transmits the electric energy output by power regulation, superposes the electric energy output by double-path electric energy coupling and stores the superposed electric energy by the energy storage module, and when the converted electric energy is smaller than the first voltage threshold value and larger than a second voltage threshold value, the access control module outputs the superposed electric energy. And when the voltage is smaller than a second voltage threshold value, electric energy coupling is stopped, the power regulation module is controlled to carry out power regulation on the electric energy released by the energy storage module, and power is supplied to the output module. According to the intelligent silicon controlled voltage conversion circuit, the utilization rate of photovoltaic electric energy can be improved, and the voltage gain and the power supply efficiency are improved.

The invention discloses a high-precision power supply output correction method based on a digital pre-distortion technology, and relates to the technical field of power electronics, and the method comprises the steps: integrating an electricity-heat-magnetism real-time combined observer, and inputting parameters including a power supply output voltage, a current, a power device junction temperature, a magnetic element surface temperature, an environment temperature, and an input voltage ripple; using a hierarchical memory depth pre-distortion compensator to generate an anti-phase pre-distortion signal containing long time domain thermal constant compensation and short time domain capacitance energy storage compensation based on modeling engine output; based on a double-ring adaptive updating module, an inner ring updates electrical parameters, including on resistance and dead time, by taking a switching period as a reference, and an outer ring updates thermomagnetic parameters, including thermal resistance and a magnetic core saturation point, in a minute-level period; and the DAC is connected in series with a pre-distortion signal output end through an anti-interference execution channel, and comprises a noise shaping DAC and a driving stage for delay matching. According to the invention, through an electric-thermal-magnetic three-field combined observation architecture, the limitation of traditional single physical field monitoring is broken through.

A power switching device is disclosed. The power switching device includes a cascode switching circuit comprising a normally-on transistor and a normally-off transistor provided in a cascode topology. The power switching device also includes a gate driver circuit configured to apply a positive bias voltage at a respective gate terminal of the normally-on transistor under a normal operating condition, and to apply a negative bias voltage at the respective gate terminal of the normally-on transistor under a short circuit condition.

The invention discloses a multi-objective optimization method and system for dual active bridge circuit expansion phase shift modulation, and the method comprises the steps: calculating a voltage matching ratio, and determining an external phase shift angle ratio based on a difference value between an output voltage and an output voltage reference value; according to the voltage matching ratio and the external phase shift angle ratio, obtaining an internal phase shift angle ratio of the primary side full bridge through an offline lookup table; calculating the maximum transmission power of the dual-active bridge converter, and determining a current working mode from the six preset working modes based on the size relationship between the inner phase shift angle ratio and the outer phase shift angle ratio; generating an optimal modulation strategy through a multi-objective optimization algorithm by taking the current effective value and the current peak value as optimization objectives and combining the voltage matching ratio and the periodic parameters of the current working mode; and generating a trigger signal of each switch tube of the dual-active bridge converter. Through six-mode working area division, complete differential algorithm boundary constraint and off-line-on-line collaborative optimization, the contradiction between the current stress and the soft switching range of the converter under extended phase shift modulation is solved.

The invention relates to the technical field of electric energy conversion control, and discloses a multi-source load auxiliary power supply power balance control system, which comprises a sampling module, a control module and a modulation module, the sampling module obtains parallel converter branch current and direct current bus voltage; the control module determines a weight by utilizing physical associated association of a bus voltage change gradient and branch current change polarity, corrects a dynamic slope factor determined by a current change rate according to the weight, and performs upper limit clamping on the dynamic slope factor according to a bus voltage margin; according to the invention, the rigid restriction of droop control logic is eliminated, the power deviation generated by asymmetry of feeder impedance is automatically offset while the bus voltage stabilization precision is maintained, and the convergence speed and the certainty of the system during violent load switching are improved.

The present application provides a converter and a chopper transistor blocking control method therefor. According to the chopper transistor blocking control method, when switching transistors in a converter need to be blocked, switching transistors in a primary side circuit connected to a transformer of the converter are blocked, and switching transistors in a secondary side circuit are blocked when the current on a branch where a secondary side winding in the transformer is located is zero, or batch blocking of the switching transistors in the secondary side circuit is completed after the current on the branch where the secondary side winding is located recirculates to zero, thereby avoiding overvoltage damage to the switching transistors caused by the current on the branch where the secondary side winding is located recirculating by means of the junction capacitance of the switching transistors in the secondary side circuit.

A buck converter including a high-side switch, a low-side switch and a bootstrap (BOOT), under-voltage lockout (UVLO) circuit. The BOOT UVLO circuit includes a BOOT UVLO detection element configured to compare a BOOT voltage with a switch node (SW) voltage to determine an occurrence of a BOOT UVLO event. The BOOT UVLO detection element is configured to output an UVLO signal (UVLO_Z), in case of the BOOT UVLO event. The BOOT UVLO circuit further includes a logic gate configured to receive the UVLO_Z and a high-side ON, (HSON) signal, the HSON signal is for controlling a switching of the high-side switch. The logic gate is configured to negate the HSON signal when receiving the UVLO_Z while the HSON signal is ON, to thereby immediately switch OFF the high-side switch when the HSON signal is ON.

A power supply control device includes: an output stage circuit having a high-side transistor provided between an application terminal of an input voltage and a switch terminal, and a low-side transistor provided between the switch terminal and a ground terminal; a high-side driver; a low-side driver; a switching control circuit for controlling on / off state of the high-side and low-side transistors using the low-side and high-side drivers; a boot terminal for applying a boot voltage; a rectifying element for supplying a charging current to a boot capacitor during an on period of the low-side transistor; a reverse current detection circuit for detecting a specific reverse current state in which a reverse current flows from an output terminal to which the output voltage is applied, toward the low-side transistor via the coil and the switch terminal; and a monitor circuit for monitoring a height of the boot voltage.

The invention discloses a TCM-mode-based Si-SiC hybrid power multi-phase staggered H-bridge converter structure and a control method thereof, according to the scheme, a three-phase staggered parallel topology of a two-phase low-frequency Si-IGBT bridge arm and a one-phase high-frequency SiC-MOSFET bridge arm is adopted, and a TCM control strategy is combined, so that zero voltage switching (ZVS) of a Si device is successfully realized, the switching loss is remarkably reduced, and the switching efficiency is improved. The system efficiency is greatly improved; and meanwhile, through pilot frequency interleaving and ripple compensation technologies, total output current ripples are greatly reduced, and optimal balance between system performance and manufacturing cost is realized while the power capacity of the converter is remarkably expanded and the dynamic response speed and the output electric energy quality are improved.

The power supply conversion circuit includes an isolation transformer, and the isolation transformer includes at least two primary coils and at least one secondary coil. Each primary coil is connected to a half-bridge circuit by using a first resonant network, and half-bridge circuits corresponding to the at least two primary coils are connected in series between two electrodes of a power supply. The half-bridge circuit is connected in parallel to a voltage divider, the voltage divider includes a first capacitor and a second capacitor that are connected in series, a first terminal of the first resonant network is connected to an intermediate node of the half-bridge circuit, and a second terminal of the first resonant network is connected to a connection point between the first capacitor and the second capacitor.

A multiple input converter for outputting power from AC power or a battery to positive and negative direct current (DC) buses is provided. The multiple input converter includes at least one bridge arm unit and a bidirectional DC-DC conversion unit. The bridge arm unit corresponds to one phase of the alternating current (AC) power and includes an upper and lower bridge arms that can independently form a two-level converter. In a battery mode, the upper and lower bridge arms discharge power from the rechargeable battery to the positive and negative DC buses, and the bidirectional DC-DC conversion unit discharges power from the rechargeable battery to the positive and negative DC buses or balances voltages of the positive and negative DC buses. In a mains mode, the bridge arm units are connected to the AC power. The bidirectional DC-DC conversion unit determine whether to charge or discharge according to load conditions.

The present invention provides a battery energy storage parallel equalization converter topology and a control method therefor. The battery energy storage parallel equalization converter topology comprises a series-connected battery energy storage parallel equalization converter, a main converter, and a plurality of groups of filter inductors; in the main converter, the input side of a DC / DC or DC / AC converter is connected in parallel to a parallel voltage-stabilizing capacitor, and the output side of the DC / AC or DC / AC converter is correspondingly connected to an AC or DC source load; the series-connected battery energy storage parallel equalization converter comprises a plurality of groups of small-capacity DC / DC converters and a common DC bus capacitor; the output sides of all the small-capacity DC / DC converters are connected in parallel by means of the common DC bus capacitor to form a common DC bus; the input side of one group of small-capacity DC / DC converters is connected in series to the input side of the main converter, and the input sides of other groups of small-capacity DC / DC converters are connected in series to a battery pack by means of the filter inductors, respectively. According to the present invention, in a battery charging and discharging process, only a small amount of power flows through the converter, reducing the capacity requirements of the converter, and reducing the transmission efficiency.

The invention discloses a wide-gain multi-mode bidirectional CLLLC resonant converter and a segmented hybrid modulation method thereof, and belongs to the technical field of power electronic conversion devices. The wide-gain multi-mode bidirectional CLLLC resonant converter is designed, the advantages of two modulation strategies of PFM and PSPSM in different working states are combined, an over-resonance part modulated by the PFM is replaced by a quasi-resonance part modulated by the PSPSM, the converter is prevented from running in an over-resonance state, the control targets of wide voltage gain and high efficiency are considered, and the wide-gain multi-mode bidirectional CLLLC resonant converter has the advantages of being scientific, reasonable, low in cost and the like. The applicability is high, and the effect is good. The wide-gain multi-mode bidirectional CLLLC resonant converter is small in size, low in cost and reasonable in structure. The PFM + PSPSM segmented hybrid modulation method effectively widens the voltage gain of the converter, is scientific and reasonable, has strong applicability and prominent effect, and is suitable for application scenes of various working conditions.

A fault tolerance method based on a seabed medium-voltage direct-current converter, and a redundant topological structure are provided. The method controls and adjusts working states of resonant conversion modules and switch states of redundant switching structures connected to the resonant conversion modules, to supply power to a load; and in the process of supplying power to the load, obtains fault diagnosis results for the resonant conversion modules. Based on the fault diagnosis results, that a faulty module exists in the resonant conversion modules, the faulty module is removed. After the faulty module is removed, a redundant resonant conversion module is determined, and the working state of the redundant resonant conversion module and the switch state of the redundant switching structure connected to the redundant resonant conversion module are adjusted, wherein the redundant resonant conversion module is configured to replace the faulty module.

The invention discloses a CLLLC converter light load efficiency improvement and load expansion circuit based on variable resonant cavity regulation and control and a control method thereof. The circuit comprises a primary side full bridge, a variable resonant cavity, a secondary side rectifier and an output loop, the digital control unit detects the load in real time, and drives and switches the parallel or series capacitor branch to adjust the equivalent resonant capacitor; and the auxiliary buffer branch is used for soft start and sudden change buffer. According to the control method, capacitance is reduced during light load, efficiency is improved, capacitance is increased during heavy load, gain linearity is kept, the load range is widened, and smooth starting is achieved. The device is compact in structure and easy to control, the light load efficiency can be remarkably improved, the load application range is expanded, and the device has high reliability and good industrialization prospects.

The disclosure provides a method for improving the efficiency of a micro-inverter, and a dual-active-bridge-type micro-inverter. The method including: performing power modulation mode switching of a dual-active-bridge-type micro-inverter, such that the power is bi-directionally transmitted from a direct-current side to an alternating-current side and from the alternating-current side to the direct-current side, thereby reducing an effective value of a secondary side current of a transformer; and according to the modulation mode switching characteristic of the dual-active-bridge-type micro-inverter within a power frequency period, performing hybrid optimization on the turn ratio of a primary side to a secondary side and a transformer leakage inductance of a high-frequency transformer of the dual-active-bridge-type micro-inverter.

The invention discloses a low-cost charging pile topology for a fast charging-slow discharging scene of an electric vehicle and a modulation strategy of the low-cost charging pile topology. According to the low-cost charging pile topology, a group of half-bridge type shunt diodes are connected in parallel to each phase of main bridge arm of a traditional T-shaped three-level converter. In the discharging mode, the charging pile is consistent with a traditional T-type three-level operation state, and works in a slow-release scene with rated power and below. In the charging mode, the charging pile continuously shunts the main bridge arm power device by using the additionally arranged shunting diode, so that the current stress and thermal stress of the main bridge arm power device are reduced; and through a self-adaptive modulation strategy of three-level / two-level modulation mode switching, the loss distribution of a power device is optimized, the active power output capability of the charging pile in a charging mode is improved, the fast charging operation of the charging pile with over-rated power is realized, the equipment capacity utilization rate of the charging pile is fully excavated, and the method has remarkable engineering application value.

The invention discloses a wide-gain-range LLC resonant converter based on a variable voltage doubling rectifying structure, and belongs to the technical field of power electronic conversion. The converter comprises a primary side direct-current voltage input, a primary side full-bridge inversion structure, a resonant tank, a secondary side variable voltage doubling rectifying structure and an output load, the primary side full-bridge inversion structure comprises a left bridge arm and a right bridge arm which are formed by a switching tube Q1, a switching tube Q2, a switching tube Q3 and a switching tube Q4, and the resonant tank comprises a resonant inductor Lr, a resonant capacitor Cr and a transformer T; the secondary side variable voltage-multiplying rectifying structure comprises a diode D1, a diode D2, a diode D3, a diode D4, a diode D5, a diode D6, a switching tube Q5, a switching tube Q6, a switching tube Q7, a voltage-multiplying capacitor Cd1, a voltage-multiplying capacitor Cd2, an output capacitor Co1 and an output capacitor Co2. According to the invention, no extra resonant element is needed, the voltage gain range can be widened, the full-range working efficiency is improved, and new energy scene requirements are met.

The present invention provides a method for cooperatively suppressing a common-mode voltage and current harmonics of coupled three-level inverters, comprising: based on amplitude and phase angle of reference voltage vector, determining sector and region in which the reference voltage vector is located; selecting four basic voltage vectors with low common-mode voltage amplitudes to synthesize the reference voltage vector; writing volt-second balance equation based on selected basic voltage vectors, and calculating duty cycles thereof; and based on sector and region in which reference voltage vector is located, set value of voltage difference across capacitors on direct current side, and actual value of voltage difference across capacitors on direct current side, (1) updating duty cycles of basic voltage vectors, to realize separate control of capacitor voltage; and (2) designing and converting switching sequence into PWM drive signal of power switch, to control the coupled three-level inverter to operate.