56 results about "Switching frequency control" patented technology

The invention relates to the technical field of power electronic conversion, and discloses a high-efficiency rectification conversion system and a control method thereof, and the system comprises the following modules: a detection module, an input compatible module, a hybrid power device module, a control module, a thermal management module and a frequency modulation module. The control method comprises the following steps: acquiring input power grid voltage, output current and load state parameters; calculating an input voltage phase difference; dynamically selecting the type and channel configuration of the silicon carbide or gallium nitride power device according to the load rate; outputting a device configuration instruction and a switching frequency control instruction; adjusting the cooling system through the evaluated thermal state of the conversion system; and the control module receives the control instruction output by the control module and is used for implementing a corresponding pulse width modulation strategy. According to the method, a multi-system power grid identification and self-adaptive topology switching strategy is adopted, the technical effect of automatically configuring the optimal rectification architecture under different input types is achieved, and the problems of response delay and poor compatibility of the method in the environment of variable power grid types are solved.

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.

This invention relates to a thermal control method for grid-connected converters that balances low harmonics and junction temperature limitations, belonging to the field of intelligent power electronics control. It employs a DPWM modulation method that locks the optimal clamping interval under overload conditions and couples this method with switching frequency control. Offline simulation is used to scan the switching frequency, obtaining data on the peak junction temperature and grid current variations as a function of the switching frequency, which is then stored in a lookup table accessible to the controller. During operation, feasible switching frequency ranges are selected based on junction temperature and dual constraints, and a recommended switching frequency range is provided. Within the acceptable frequency range, the optimal frequency reduction point is selected according to a proposed selection function, thus achieving a dynamic trade-off between thermal safety and system performance during overload. This invention, by fully considering the coupling effect of DPWM and frequency reduction, provides the optimal operating frequency point to ensure the safe and compliant operation of the converter under overload conditions.

The invention relates to the technical field of power electronic control, and discloses a switching frequency control method for an isolated resonant converter and a storage medium, and the method comprises the steps: continuously monitoring the real-time load current of the isolated resonant converter under a load condition; when it is monitored that the maintenance duration of the real-time load current continuously meeting the current operation condition reaches the preset duration, the switching frequency minimum value of the isolated resonant converter is obtained, and according to the size relation between the preset switching frequency and the switching frequency minimum value, the direct-current bus voltage is adjusted in real time, so that the current operation condition of the isolated resonant converter is obtained. The switching frequency minimum value does not exceed the preset switching frequency; wherein the current operation condition is that the real-time load current is greater than or equal to a preset current threshold value. According to the invention, the minimum value of the switching frequency is adjusted by adjusting the voltage of the direct-current bus, so that the device works at the optimal frequency, the EMI of the product is reduced, the size of the magnetic device does not need to be increased specially, the device cost can be remarkably reduced, and the power density of the product is improved.

The invention provides an asymmetric modulation method and device for a bidirectional resonant DAB converter, and the method comprises the steps: determining the real-time duty ratio of any switching tube in a primary full bridge through the real-time working parameters of the bidirectional resonant DAB converter, and determining the real-time switching frequencies of a switching tube corresponding to the primary full bridge and a switching tube corresponding to a secondary full bridge, and enabling the real-time duty ratio of other switching tubes located on the same bridge arm with any switching tube to be complementary with the real-time duty ratio of any switching tube, thereby obtaining the real-time duty ratio of any switching tube according to the real-time duty ratio of the switching tube of the primary full bridge, the real-time duty ratio of the switching tube of the secondary full bridge and the real-time switching frequency. And controlling the switching states of a switching tube corresponding to the primary side full bridge and a switching tube corresponding to the secondary side full bridge, and asymmetrically modulating the bidirectional resonant DAB converter, thereby realizing the asymmetrical control of the positive high level duration and the negative high level duration of the midpoint voltage of the bridge arm of the primary side full bridge, and optimizing the reactive power.

The invention relates to the technical field of LLC resonant converters, in particular to an LLC resonant converter control method and system based on output diode current detection, and the method comprises the steps: conditioning the output current of an LLC resonant converter; designing a control outer ring, and calculating an error signal of the reference current and the diode conditioning current; the stability of the output current is maintained by using the offset and adjusting the integral slope; the compensation amount of the offset is adjusted, and the offset and the integral slope are given to the control inner ring, so that the control inner ring works in the optimal working interval; the control inner ring detects the conditioning current, integrates the conditioning current, compares the integral conditioning current with the error signals of the reference current and the offset, and outputs the switching frequency; and a switching tube of the converter is controlled by using the switching frequency to control the output current, so that the converter enters a new steady state. The problems that an existing control method of the converter cannot meet the requirements of small input filter capacitance, output voltage ripple suppression, input disturbance resistance and the like at the same time are solved.

The invention provides a power conversion device and a conversion method thereof. The power conversion device comprises a transformer circuit and a bridge rectifier switching circuit coupled with an input side circuit of the transformer circuit, and the switching frequency control circuit generates compensation frequency according to input voltage of the bridge rectifier switching circuit and adjusts switching frequency of the bridge rectifier switching circuit according to the compensation frequency.

An apparatus includes a logic circuit having a clock input, a first logic circuit control output, and a second logic circuit control output. A clock generation circuit has a first clock control input, a second clock control input, and a clock output. The clock output is coupled to the clock input. An off-timer circuit has an off-timer output. A comparator has a comparator output. An out-of-audio (OOA) circuit has a first OOA input, a second OOA input, a third OOA input, a first OOA output, and a second OOA output. The first OOA input is coupled to the comparator output. The second OOA input is coupled to the clock output. The third OOA input is coupled to the off-timer output. The first OOA output is coupled to the first clock control input. The second OOA output is coupled to the second clock control input.

The invention relates to a network construction type converter thermal control method considering low harmonic waves and junction temperature limitation, which belongs to the field of power electronic intelligent control, and comprises the following steps: locking a DPWM modulation mode of an optimal clamping interval under an overload condition, and carrying out coupling design with switching frequency control; switching frequency is scanned through off-line simulation, data of device peak junction temperature and grid-connected current changing along with the switching frequency are obtained respectively, and the data are solidified into a lookup table capable of being called by a controller; during operation, a feasible switching frequency interval is screened according to junction temperature and double constraints, a recommended switching frequency interval is given, and an optimal frequency reduction working point is selected according to a provided selection function in the frequency interval meeting requirements, so that dynamic compromise between thermal safety and system performance during overload is realized. According to the method, the optimal operation frequency point is given under the condition of fully considering the DPWM and frequency reduction coupling effect, so that the safe and compliant operation of the converter under the overload working condition is realized.

The utility model discloses an LED abnormity monitoring control circuit and a monitoring controller, the LED abnormity monitoring control circuit comprises a power supply management circuit which comprises a positive connection end and a negative connection end, an LED lamp group is electrically connected between the positive connection end and the negative connection end, a sampling control unit is electrically connected with the LED lamp group, and the sampling control unit is electrically connected with the LED lamp group. The sampling control unit is configured to control the connection or disconnection of the LED lamp group and the power management circuit at at least one first switching frequency, so that the current passing through the LED lamp group is kept at a first threshold value; when it is monitored that the current passing through the LED lamp set is larger than or equal to a second threshold value, the LED lamp set and the power management circuit are controlled to be switched on or switched off at least at a second switching frequency, and the second threshold value is larger than the first threshold value, so that the sampling control unit is introduced, the current of the LED lamp set can be monitored in real time, protection measures are taken in time when the current is increased abnormally, and the service life of the LED lamp set is prolonged. And the LED lamp group is prevented from being damaged. And meanwhile, the current of the LED lamp group can be controlled, so that the LED lamp group keeps stable brightness output.

A controller circuit is configured to generate, using a random number generator, a set of bits and determine a switching frequency using the set of bits. The controller circuit is further configured to control a switching circuit to switch at the switching frequency to drive a motor.

Provided an electronic device including a main body and a kit connected to the main body, and the main body includes a battery, a first motor, an electric wire connected to the battery, and a first controller connected to the electric wire, the kit includes a second motor supplied with power through the electric wire, an inverter connected to the second motor, and a second controller connected to the electric wire and configured to control driving of the inverter, and the second controller is configured to transmit information to the first controller through switching frequency control of the inverter and control a switching frequency of the inverter so that a current associated with the second motor is greater than zero in a section in which transmission of the information is performed.

This application relates to a method, apparatus, and computer device for controlling grid connection of a flyback converter. The method includes: obtaining grid connection parameters of the flyback converter and upper and lower frequency limits of a power switch in the flyback converter; determining a number of resonant valleys of the power switch based on the grid connection parameters and the upper and lower frequency limits; obtaining a switching frequency of the power switch based on the grid connection parameters and the number of resonant valleys; and controlling the power switch based on the switching frequency. Application of this method improves safety.

Operating system for a hybrid inverter coupled to a multiphase electric machine, comprising first gate drivers with wide-bandgap (WBG) transistors connected to a first subset of transistors, second gate drivers with silicon-based (Si) transistors connected to a second subset of transistors, and a controller. The hybrid inverter includes the first subset and the second subset of transistors arranged in phase branches, including a first section of the phase branches utilizing the first subset of transistors and a remaining section of the phase branches utilizing the second subset of transistors. The first gate driver controls the first section of the phase branches at a first switching frequency. The second gate driver controls the second section of the phase branches at a second switching frequency.The second switching frequency is lower than the first switching frequency.

The invention belongs to the technical field of electronic circuits, and provides a resonant converter. The resonant converter comprises an input end, an output end, a first switch, a second switch, a third switch, a fourth switch, a frequency controller, a resonant capacitor, a first transformer, a second transformer and a feedback circuit, the input end is connected with an external power supply, and the output end is connected with an external load. The feedback circuit feeds back the change of the current at the output end of the resonant converter to the frequency controller, and the frequency of a control signal output by the frequency controller changes in an inverse proportion along with the current of the external load so as to adjust the voltage at the output end of the resonant converter; according to the resonant converter, the primary side of the transformer is used for replacing a resonant inductor, energy stored by the primary side of the transformer can be transmitted to the secondary side of the transformer from the primary side of the transformer in a dead zone state, the switching loss of the primary side is effectively reduced, and the resonant converter can work under variable high frequency.

The application discloses a capacitor switch number control method and device, and the method comprises the following steps: obtaining the reactive power of a capacitor bank of a transformer substation and all switch displacement information of the capacitor bank; the switch displacement information contains time information, opening instruction information and closing instruction information; according to the time information, the opening instruction information and the closing instruction information are sorted and analyzed to obtain the switch action number corresponding to the capacitor bank; based on the reactive power of the capacitor bank, the capacitor bank is classified and counted to obtain a total account of capacitor bank equipment; the total account of capacitor bank equipment is associated with the switch action number corresponding to the capacitor bank to obtain capacitor switch information account based on the bus of the transformer substation; whether all the capacitors in the capacitor switch information account need to be controlled in terms of switch number is determined by using a dispersion analysis method. Therefore, the service life of the capacitor bank and the switch is prolonged, and the strategy optimization of the reactive power compensation control is realized.

The application belongs to the technical field of inverter switch control, and specifically discloses a three-level inverter switch frequency control method, device, medium and equipment. The method comprises the following steps: collecting the actual output current of the output end of the three-level inverter in real time; calculating the instantaneous error of the actual output current and the preset reference current; calculating the rising time and the falling time of the instantaneous error within the hysteresis width to obtain a natural switch period; comparing the actual output current of the output end of the three-level inverter with a set threshold to determine whether the three-level inverter enters an active frequency conversion adjustment mode; and when the active frequency conversion adjustment mode is entered, taking the natural switch period as a reference, dynamically setting the turn-on time and the turn-off time to generate a controlled switch period, so that the active adjustment of the switch frequency of the three-level inverter is realized. By adopting the segmented frequency conversion hysteresis control, the application can improve the operation reliability of the three-level inverter and prolong the service life of the power device.

The invention belongs to the technical field of inverter switching control, and particularly discloses a three-level inverter switching frequency control method and device, a medium and equipment, and the method comprises the steps: collecting the actual output current of the output end of a three-level inverter in real time; calculating an instantaneous error between the actual output current and a preset reference current; calculating rising time and falling time of the instantaneous error in the hysteresis width to obtain a natural switching period; the actual output current of the output end of the three-level inverter is compared with a set threshold value so as to judge whether the three-level inverter enters an active frequency conversion adjusting mode or not; and when the three-level inverter enters the active frequency conversion adjusting mode, the natural switching period is taken as a reference, and the turn-on time and the turn-off time are dynamically set, so that a controlled switching period is generated, and active adjustment of the switching frequency of the three-level inverter is realized. According to the three-level inverter, the operation reliability of the three-level inverter can be improved and the service life of a power device can be prolonged by adopting segmented variable-frequency hysteresis control.

The invention discloses a hysteresis current control method and system for a fixed-frequency grid-connected converter, and belongs to the technical field of converter control. The method comprises the following steps: calculating single-cycle variation and influence quantity of voltage, current instruction and hysteresis width of a power grid; calculating a frequency loop compensation gain according to the converter topology; actual switching frequency is detected and compared with an instruction value, and a ring width control instruction is generated through a PI controller; and an actual loop width instruction is obtained by combining the compensation gain, and constant switching frequency control is realized. According to the invention, through multivariable compensation and closed-loop control, the influence of power grid voltage fluctuation, current instruction change and hysteresis width adjustment on the switching frequency is effectively suppressed, the problem of unstable switching frequency of traditional hysteresis control is solved, the advantage of fast dynamic response of hysteresis control is retained, accurate and stable control of the switching frequency is realized, and the switching efficiency is improved. The method is suitable for two-level and three-level converter topologies, and has important engineering application value.

A resonant converter and a control method thereof are provided. The resonant converter includes primary and secondary circuits and a transformer. The control method includes: in first control mode, controlling primary switches of the primary circuit and secondary switches of the secondary circuit with a variable switching frequency; in second control mode, controlling a phase shift between the primary switches and the secondary switches; when an input voltage is within a preset range, controlling the resonant converter with the first control mode; when the input voltage changes from within the preset range to outside the preset range, transiting from the first control mode to the second control mode to maintain an output voltage within a predetermined range; and when the input voltage changes from outside the preset range to within the preset range, transiting from the second control mode to the first control mode.

The invention provides a split type energy storage system pairing method, a pairing system and a storage medium. The pairing method comprises the following steps: based on the rated working frequency of each inverter, distributing a switching frequency to each inverter; the inverters to be paired are controlled to perform no-load operation at the distributed switching frequency, so that the inverters generate current ripples on the corresponding direct-current power lines; controlling each battery pack to sample a current signal on the direct-current power line to obtain a current signal period; when the current signal period obtained by any battery pack meets a preset condition and lasts for a preset time, the battery pack sends battery to-be-matched frame information carrying a target frequency to a communication bus; controlling each inverter to receive to-be-matched frame information of the battery; and when it is judged that the switching frequency of any inverter during operation is matched with the target frequency in the obtained to-be-matched frame information of the battery, the inverter is controlled to send inversion matching completion frame information to the communication bus. According to the scheme, accurate pairing between the battery pack and the inverter is realized.

The invention discloses a manned mower and a control method thereof. The manned mower comprises a motor; a driving circuit including a plurality of switching elements electrically connected between the power supply device and the motor; the controller is at least electrically connected with the driving circuit; the controller is used for outputting a driving signal to the driving circuit; the driving signal at least comprises a switching frequency; the controller determines the switching frequency of the driving circuit based on the first parameter of the motor, and updates the switching frequency based on the second parameter; wherein the first parameter comprises the rotating speed of the motor; the second parameter comprises at least one of the torque of the motor, the current of the motor, the bus voltage of the motor and the temperature of the controller; the switching frequency is increased along with the increase of the rotating speed of the motor in each rotating speed interval; or the switching frequency is increased along with the increase of the rotating speed of the motor among the rotating speed intervals. According to the technical scheme of the invention, the control precision and the switching loss of the driving circuit can be considered during the operation of the manned mower.

This invention provides a three-port converter and a three-port power conversion system, relating to the field of circuit technology. The converter can bidirectionally transfer power between three ports, each of which can operate as a power source or load. It includes a primary-side switching network at the first port for driving a transformer, and secondary-side resonant tank circuits at the second and third ports. The converter achieves electrical isolation and provides voltage gain. The system includes a controller configured to monitor the voltage and power at each port and generate gate drive signals to regulate power transfer between the input port and at least one output port via switching frequency control. A cross-regulation function allows the voltage at one port to be fine-tuned to a target value while maintaining the voltage at another port at a substantially constant state. The converter can employ a variant design of a multiphase transformer to distribute conduction losses and thermal stress, and improve power handling capacity.

The invention provides a control method and device of a series resonance dual-active bridge conversion circuit and a converter. The series resonance dual-active bridge conversion circuit comprises a primary side full-bridge circuit and a secondary side full-bridge circuit, the primary side full-bridge circuit comprises a first switching tube, the secondary side full-bridge circuit comprises a second switching tube, and the first switching tube and the second switching tube are connected through a resonance circuit in the series resonance dual-active bridge conversion circuit. The control method comprises the steps that a target phase shift angle is determined according to the output voltage and the output voltage reference value of the secondary side full-bridge circuit, and the target phase shift angle is the inter-bridge phase shift angle of the series resonance dual-active bridge conversion circuit; determining a target switching frequency according to the minimum value of the sum of the absolute value of the turn-off current of the first switching tube and the absolute value of the turn-off current of the second switching tube; and controlling on and off of a switching tube in the conversion circuit according to the target phase shift angle and the target switching frequency.

The application discloses a power converter control method applied to a power converter with a common primary full-bridge switching circuit of an interleaved parallel Boost circuit and a dual active bridge converter. The output voltage, output current, grid voltage and grid-connected current of a photovoltaic module are collected, the target duty ratio of the primary full-bridge switching circuit is calculated based on the photovoltaic output parameters, the grid synchronous phase is obtained at the same time, the phase-shifted ratio adjustment amount is obtained by closed-loop regulation of the grid-connected current, the nominal phase-shifted ratio of the primary and secondary sides of the dual active bridge converter is calculated through the grid-connected current mathematical model in combination with the photovoltaic output voltage, the preset maximum switching frequency threshold and the grid-connected current reference value, the actual phase-shifted ratio and the real-time switching frequency matched with the actual phase-shifted ratio are determined after the nominal phase-shifted ratio is superimposed with the phase-shifted ratio adjustment amount in combination with the target duty ratio and the grid synchronous phase, and finally, the photovoltaic maximum power point tracking and unit power factor grid-connected inversion are realized by controlling the power converter based on the target duty ratio, the actual phase-shifted ratio and the real-time switching frequency.

The invention discloses a manned lawn mower. The manned lawn mower comprises a motor; an output member; a power supply device; a driving circuit including a plurality of switching elements electrically connected between the power supply device and the motor; the controller is at least electrically connected with the driving circuit; the controller is used for outputting a driving signal to the driving circuit to enable the motor to operate; the driving signal at least comprises a switching frequency; the controller is configured to control the switching frequency of the driving signal to be a first switching frequency f1 when the rotating speed of the motor is in a first rotating speed interval, and control the switching frequency of the driving signal to be a second switching frequency when the rotating speed of the motor is in a second rotating speed interval; wherein the first switching frequency and the rotating speed of the motor are in a first positive correlation, and the second switching frequency and the rotating speed of the motor are in a second positive correlation. According to the technical scheme of the invention, the control precision and the switching loss of the driving circuit can be considered during the operation of the manned mower.

The application relates to a permanent magnet synchronous motor current control method of an adjustable switching frequency FCS-MPC, and compared with the prior art, the method solves the defect that the switching frequency of an inverter is not fixed in the existing FCS-MPC permanent magnet synchronous motor system current control. The method comprises the following steps: collecting drive system data; constructing a discretized current prediction control model; determining a cost function and a delay compensation strategy; calculating a current error control band; selecting an optimal voltage vector; and outputting the voltage vector. The method retains the unique advantages of FCS-MPC, overcomes the inherent defect that the switching frequency is not fixed, enables FCS-MPC to operate at a specified switching frequency within a wide speed regulation range, and through the introduction of a PI type switching frequency controller, can realize the zero-error tracking of a switching frequency reference value. The control method realizes effective regulation and control of the switching frequency on the basis of guaranteeing the current control performance of the permanent magnet motor.

An electronic device is provided. The electronic device includes: a first transistor configured to connect an input voltage node to a switching node; a second transistor configured to connect the switching node to a ground node; a latch circuit configured to generate a first signal having a first frequency and to control the first frequency based on a level of a load current; a switching modulation circuit configured to generate a second signal having a second frequency which is 1 / N (where N is a natural number) times the first frequency; and a controller configured to control each of the first transistor and the second transistor, based on the second signal.

Resonant power supply device (101) comprising the following: a main power supply circuit (102) comprising a transformer (107), a resonant element (106) connected to a primary side of the transformer (107), and several switching elements (105a, ..., 105d) connected to the resonant element (106); and a power supply control circuit (103) that switches the several switching elements (105a, ..., 105d) in the main power supply circuit (102) at a predetermined switching frequency, wherein the power supply control circuit (103) includes the following: a voltage control unit (202) which outputs a current command value from a reference voltage, an output voltage of the main power supply circuit (102) and a voltage control gain; wherein the voltage control unit (202) performs arithmetic processing such that the current command value decreases when the output voltage is greater than the reference voltage, and increases when the output voltage is less than the reference voltage; a current control unit (203) which calculates the switching frequency from the current command value, an output current flowing on a secondary side of the transformer (107), and a current control gain; wherein the current control unit (203) performs arithmetic processing such that the switching frequency increases when the output current is greater than the current command value, and decreases when the output current is less than the current command value; a gain calculation unit (504) that outputs the voltage control gain and the current control gain; and a control signal generator (113) which, based on the switching frequency output by the current control unit (203), controls several switching elements (105a, ..., 105d), wherein the gain calculation unit (504) outputs the voltage control gain or the current control gain which are proportional to the switching frequency output by the current control unit (203).

The invention relates to audio output switching frequency control. An apparatus includes a logic circuit (120) having a clock input, a first logic circuit control output, and a second logic circuit control output. The clock generation circuit (110) has a first clocked input, a second clocked input, and a clock output. The clock output is coupled to the clock input. A turn-off timer circuit (160) has a turn-off timer output. The comparator (140) has a comparator output. An audio output (OOA) circuit (170) has a first OOA input, a second OOA input, a third OOA input, a first OOA output, and a second OOA output. The first OOA input is coupled to the comparator output. The second OOA input is coupled to the clock output. The third OOA input is coupled to the turn-off timer output. The first OOA output is coupled to the first clocked input. The second OOA output is coupled to the second clocked input.