271results about How to "Achieve power" patented technology

The invention discloses a twin-motor two-planet-row and single clutch driving device of a hybrid vehicle in the technical field of machinery. The device is provided with a front planet row and a back planet row; the front planet row is provided with a front planet row planet wheel and a front planet row sun gear; the back planet row is provided with a back planet row planet wheel and a back planet row sun gear; the front planet row and the back planet row share a gear ring. The output shaft of an engine is connected with the input end of an integrated starter generator; the output end of the integrated starter generator is connected with the driving disk of the clutch; the driven disk of the clutch is connected with the planet wheel of the front planet row through a planet carrier; the sun gear of the front planet row is connected with a drive motor; the planet carrier of the planet wheel of the back planet row is arranged fixedly on a car frame; the sun gear of the back planet row is also connected with the drive motor; the outside gear of the gear ring is normally engaged with a power take-off gear. The twin-motor two-planet-row and single clutch driving device of the hybrid vehicle has the advantages of compact structure, large transmission ratio, large load support capability, stable driving, and high transmission efficiency, thereby realizing power dividing and infinite variable speed at the same time.

The invention relates to an electromechanical coupling transmission device of a crawler. The device comprises an engine, a power coupling and gear shifting mechanism, two motors, a power control unit and an energy storage system, wherein the two motors are connected with sun gears of two planet rows of the power coupling and gear shifting mechanism respectively, a gear ring of the two planet rowsof the power coupling and gear shifting mechanism is shared, a clutch is arranged between the two sun gears and the shared gear ring, and the shared gear ring is provided with a brake and output through a planet carrier. The transmission device removes a steering gear set and a zero shaft of double-flow transmission of the crawler, and has flexible allocation, capability of making full use of space and compact structure. Because of the power coupling and gear shifting mechanism, the requirement for the motors is reduced, and the research and manufacture risks of the motors are reduced.

The invention discloses a hybrid car driving system which comprises a driving motor operating mode switching device, and belongs to the technical field of vehicle engineering, wherein, an engine is connected with an integral start generator coaxially; the integral start generator is connected with a first automatic clutch driving disc; a first automatic clutch driven disc is connected with a planetary gear mechanism by a driving motor; one side of the planetary gear mechanism is connected with the driving motor by a second automatic clutch, and the other side thereof is connected with a main reducer-differential mechanism; the main reducer-differential mechanism is connected with wheels by a driving axle; a power battery pack is respectively connected with a motor controller and an external power supply plug by cables; and the motor controller is respectively connected with the integral start generator and the driving motor by the cables. An outer gear ring of the planetary gear mechanism is connected with a frame fixedly. The hybrid car driving system reserves the traditional vehicle structure to a maximum extent and optimizes the working point of the engine by using double motors, thus leading the engine to operating stably in a high-efficiency and low-discharge area, simultaneously optimizing the working condition of the driving motor and prolonging the service life of the motor.

The invention discloses a two-planet-row electromechanical coupling driving device of a hybrid vehicle in the technical field of machinery. The device is provided with a front planet row and a back planet row; each of the two planet rows is provided with a planet wheel, a sun gear and a row gear ring; the two planet row gear rings are connected with each other by a clutch. An engine is connected with the planet wheel of the front planet row; an ISG motor is connected with the sun gear of the front planet row; the gear ring of the front planet row is connected with the driving disk of the clutch; the driven disk of the clutch is connected with the gear ring of the back planet row; the planet carrier of the planet wheel of the back planet row is arranged fixedly on a car frame; the sun gear of the back planet row is connected with a drive motor; the outside gear of the gear ring of the back planet row is normally engaged with a power take-off gear. The two-planet-row electromechanical coupling driving device of the hybrid vehicle has the advantages of compact structure, large transmission ratio, large load support capability, stable driving, and high transmission efficiency, thereby realizing power dividing and infinite variable speed at the same time.

The invention relates to a topological structure of a multi-level photovoltaic power generation system and a control method of the topological structure. The topological structure comprises M photovoltaic arrays, the boost DC / DC (direct current / direct current) converters of the M photovoltaic arrays, 3n isolation flyback DC / DC converters and 3n H-bridge voltage source inverters. The PWM (pulse-width modulation) control signals of the first to nth H-bridge voltage source inverters of the three phases A, B and C of the cascade H-bridge multi-level voltage source inverters are obtained through an active power calculation method of a super-capacitor direct-current bus voltage controller and a photovoltaic array, and current tracking control of a dq synchronous coordinate system; the PWM control signals of the electronic power switches S2 of the wth and kth isolation flyback DC / DC converters are obtained through a control method of the isolation flyback DC / DC converters; the PWM control signals of the electronic power switches S1 of the j boost DC / DC converters are obtained through a control method of the boost DC / DC converters. The topological structure has the benefits that the shortcomings of large volume and high cost of power-frequency boosting transformers used when existing large-scale photovoltaic power generation systems are connected to a power grid are overcome.

The invention belongs to the field of applied superconducting power electronics, and in particular relates to a synchronizing current and voltage decoupling control method of a voltage-source-type unit power factor high-temperature superconducting energy storage system converter. The control method is characterized by comprising the following steps: designing a voltage outer ring control module at a direct-current side and a current inner ring control module at an alternating-current side respectively with respect to a mathematical model of a superconducting energy storage system converter under dq synchronizing rotary coordinates; controlling an 'H'-shaped bidirectional DC-DC (direct-current to direct-current) chopper based on an SPWM (sinusoidal pulse width modulation) technology by adopting a hysteresis loop PI current closed-loop control method in a charge mode and a hysteresis loop PI voltage closed-loop control method in a discharge mode; and finally implementing the synchronizing current and voltage double-fed control method of a voltage-source-type SMES (superconducting energy storage system) converter according to the active current requirement and the current value of a superconducting magnet under the power grid unit power factor. The control method provided by the invention has the advantages of multi-stage current decoupling control, rapid response speed, easy implementation of control algorithm and the like, and the method is especially suitable for the application occasions for improving the electricity energy quality of a power grid and inhibiting the low-frequency oscillation of a power system and the like.

An electric system that includes a single-phase permanent-magnet electric machine and a control system for driving the electric machine. The control system sequentially excites and freewheels a winding of the electric machine so as maintain substantially constant power over an operating speed range spanning at least 10 krpm and / or an excitation voltage range extending between a minimum voltage and a maximum voltage, the minimum voltage being less than 80% of the maximum voltage. Additionally, a product comprising the electric system.

The invention discloses a self-adaptive energy management system for fuel cell hybrid power tramcar multi-power source. The system comprises a fuel cell system unit, a lithium battery unit, a supercapacitor unit, a one-way DC converter unit, a bidirectional DC converter unit interface and a self-adaptive energy management unit, wherein the self-adaptive energy management unit is formed by a power distribution processing sub-unit capable of distributing power and a double self-adaptive nerve cell fuzzy inference sub-unit capable of conducting self-adaptive energy control; power among the fuel cell unit, the lithium battery unit and the supercapacitor unit can be self-adaptively distributed in real time by real-time detection of an operation work condition and a power system condition, so the fuel cell unit can maintain stable and high efficient operation and safe charge-discharge management and effective brake energy recovery can be guaranteed for the lithium battery unit and the supercapacitor unit; work efficiency of the fished car and each power supply can be improved; and circulating service life of each power supply can be prolonged.

The invention relates to a self-adaptive networking method based on a baseband with a large-scale processing ability and business. Various access communication nodes access the baseband with the large-scale processing ability to realize intensive processing and controlling, and a three-level network of a cloud computing server, the baseband with the large-scale processing ability and the access communication nodes is formed. The baseband with the large-scale processing ability configures the access communication nodes according to the requirements of business and also self-adaptively adjusts resource and power distribution to increase the energy efficiency of the network according to the change of the business and a coverage area. User equipment covered by different access communication nodes shares the same wireless resource, the large-scale collaborative airspace interference control can also be realized, and wireless interference is reduced. As the method utilizes the baseband with the large-scale processing ability with a function for supporting heterogeneous multimode communication and a software-defined calculating ability to realize intensive controlling to network elements and sharing to the wireless resource, the wireless network realizes self-adaption to the coverage and the dynamic change of business, the energy consumption and interference of the network are reduced, and the spectral efficiency and the energy efficiency of the network are increased.

The invention belongs to the technical field of a motor, and relates to a single-winding non-bearing magnetic flux switching permanent magnetic motor. The single-winding non-bearing magnetic flux switching permanent magnetic motor comprises a stator iron core, a rotator iron core, permanent magnets embedded in the middle of stator teeth, and concentrated windings. A stator and a rotor are both of double-salient pole structures. The single-winding non-bearing magnetic flux switching permanent magnetic motor is characterized in that the stator iron core is composed of six U-shaped laminations; a permanent magnet capable of tangential alternative magnetizing is embedded between every two laminations so that a stator tooth which is axisymmetric is formed; the stator teeth are provided with the concentrated windings, the end portions of the windings are quite small, and the windings, which are opposite to each other in terms of space, on two stator teeth form a phase so that a three-phase winding is formed; and the excitation of winding currents is of a radial excitation mode, each winding is independently controlled, the winding currents can perform bidirectional flow in positive and negative directions, the current size can be controlled according to needs, and the currents has the same phase as a back electromotive force. The single-winding non-bearing magnetic flux switching permanent magnetic motor has the advantages of high speed, large power, high efficiency, high power density, high operation stability, high reliability, and adaptability to an AC operation mode.

The invention discloses a flexible ground automatic neutral-section passing system of an electrified railway. The flexible ground automatic neutral-section passing system of the electrified railway comprises a train position recognition subsystem, an electric energy characteristic monitoring subsystem and a power regulation subsystem. The train position recognition subsystem is used for recognizing the position of a train on a railway line and providing the position for the power regulating subsystem. The electric energy characteristic monitoring subsystem is used for monitoring electric energy characteristics of all power supply sections of a railway power supply network, and providing the power characteristics for the power regulation subsystem. The power regulation subsystem comprises power regulating units. Each power regulating unit comprises a first power regulation arm and a second power regulation arm, wherein the first power regulation arm is connected with the first power supply section of the power supply network, and the second power regulation arm is connected with a neural section adjacent to the first power supply section. The flexible ground automatic neutral-section passing system of the electrified railway has the advantages that an electric locomotive can pass the neutral section safely and stably without reducing the load in an electrified mode, locomotive protection parameters do not need to be modified, and the adaptive capacity is high.

The invention provides a method for controlling low-voltage ride through of a cascaded photovoltaic grid-connected inverter. The method is based on two common mathematical models of grid-side voltage under the condition of an unbalanced grid fault, and the laws between the three-phase grid-side voltage amplitude and phase under different fault conditions are summarized. A method for controlling a cascaded photovoltaic grid-connected inverter under different fault conditions is derived based on the laws. By setting the on-off state of an H-bridge power device, a bypass power unit controls low-voltage ride through of a cascaded photovoltaic grid-connected inverter. When a bypass is generated, the optimal modulation ratio of a normal operation unit is recalculated, and a carrier phase shift module is adjusted to produce a new PWM pulse signal. The method can ensure that a photovoltaic grid-connected inverter outputs symmetrical three-phase current during grid-side voltage failure and enable the photovoltaic grid-connected inverter to run under unit power factor, and is of great significance to ensuring safe and stable operation of the power grid after large-scale photovoltaic power integration.

The invention discloses a material cutting power and energy consumption obtaining and energy-saving control method in a variable cutting rate process. The method includes the steps that 1, value combinations of cutting elements are obtained, and the empty feeding power and cutting power of a machine tool are collected in real time for each value combination; 2, the material cutting power of a subsection is obtained according to the empty feeding power and the cutting power of the subsection; 3, the material cutting power and the value of the corresponding cutting element are put into an average cutting power computational formula of the subsection, and fitting is carried out; 4, the material cutting power and energy consumption computational formula of the variable cutting rate process is obtained according to functions of the cutting elements relative to time; 5, the material cutting power peak value and the energy consumption value of the variable cutting rate process are obtained after calculation, and the optimal variable cutting rate process is selected for cutting. According to the method, operation is easy, accuracy of predicting the power and energy consumption is high, and the method can be conveniently popularized to combination of machine tools, work piece materials and tools of other types.

The invention relates to a reactive power compensation method and a reactive power compensation system for a micro power grid. The system comprises a distributed measuring unit, a reactive power compensation control unit, a reactive power compensation unit and a communication unit. The micro power grid comprises a distributed power supply with reactive regulation output. For the micro power grid operated in an isolated network mode, the overall reactive power balance condition of the micro power grid is obtained by measuring the active and reactive power distribution conditions of each branchcircuit of the micro power grid, and a reactive power compensation device or the reactive power compensation device and the distributed power supply are subjected to reactive regulation in the micro power grid according to a specific isolated network reactive control strategy to realize the reactive power compensation of the micro power grid. The power factor of the micro power grid can be measured and corresponding reactive power compensation is performed according to the power factor when the micro power grid is operated in a grid-connected mode and in the isolated network mode.

The invention discloses a voltage-equalizing and power-equalizing control method for a three-phase multi-module cascade solid-state transformer. A three-phase SST system power main circuit part applied in the method comprises an input stage, an intermediate stage and an output stage, wherein a control policy based on three-phase d-q-0 vector control is adopted in the input stage, a common duty ratio control policy is adopted in modules in the same phase so as to achieve the unit power factor of an input end of an electric network; a control policy based on voltage feedforward and voltage feedback is introduced for each module in the intermediate stage, the voltage feedforward is used as a reference of the voltage feedback, and an error between the voltage feedforward and the voltage feedback is used as a reference of an inner current loop of each module after being output by a voltage PI adjuster. The two control policies of the front stage and the intermediate stage interact so as to achieve the functions of voltage and power equalization of each SST module, electrical network side unit power factor, high electrical network current sine degree, low switching tube voltage stress and the like.

The invention relates to an electric control system of an asynchronous wind generating set. The electric control system comprises a master control system (MCS), a full power converter, a machine side self-excited capacitor unit (SCU), a breaker K and a converter controller KZQ, wherein an A port and a B port are arranged on the full power converter, the A port is connected with a stator of an asynchronous generator, and the B port is connected with a power grid through the breaker K. The full power converter comprises a ram side converter (RSC), a grid side converter (GSC) and a direct current braking unit (DBU), wherein the ram side converter (RSC) and the net side converter (GSC) are connected in a back-and-back mode through a common direct current bus, and the direct current braking unit (DBU) is connected onto the common direct current bus. A filter LB1 is arranged between an alternating current input side of the net side converter and the B port, and a filter LB2 is arranged between an alternating current input side of the ram side converter (RSC) and the A port. After the MCS obtains operation information of the asynchronous wind generating set, the converter controller KZQ is used for controlling the full power converter.

The invention discloses a magnetic transmission speed-transformation device, which comprises an input module, connecting modules and an output module; the input module is connected with the connecting modules through double-layer couplers; the connecting modules is connected with the output module through the double-layer couplers; cascading number of the connecting modules is one or more than one; and when the cascading number of the connecting modules is more than one, the connecting modules are connected in series through double-layer couplers. According to the invention, the input module is connected with a power input source through an input coupler; power P is output through the input module, the connecting modules and the output module after being input through an input end of the power input source; N connecting modules can be in series according to the load situation to realize shunting transmission of N magnetic speed-transformation mechanisms, and power borne by each magnetic speed-transformation mechanism at P / N; and an output end synthesizes power of the N speed-transformation mechanisms to total power P through an output coupler for output. According to the invention, the quantity of the cascading modules is reasonably changed, so as to change systematic transmission ratio.

The invention discloses a bidirectional resonance DC converter and a control method thereof. The bidirectional resonance DC converter is formed by a low-voltage side power supply, a high-voltage side power supply, low-voltage side first switch tube-low-voltage side fourth switch tube, high-voltage side first switch tube-high-voltage side fourth switch tube, first and second resonant inductors, a resonant capacitor, first and second capacitors and a transformer. When energy is transmitted from the lower voltage side to the high voltage side, the bidirectional resonance DC converter realizes power control through phase-shifting control of the switch tubes at the two sides; and when the energy is transmitted from the high voltage side to the low voltage side, the bidirectional resonance DC converter realizes power control through frequency converting control of the switch tubes. The bidirectional resonance DC converter not only can realize bidirectional transmission and control of the energy at the two sides, but also can realize soft switching of all switch devices in full load range, and is especially suitable for being applied to high-frequency, high-efficiency and high-power-density two-way power transformation occasions.

The invention provides a chained static synchronous compensator with an active power adjusting capacity. The chained static synchronous compensator with the active power adjusting capacity comprises three phases of cascading chain links, connection reactors and breakers. Each phase of the cascading chain link comprises n cascading units which are connected in series at the alternating current side. One ends of the three phases of the cascading units are connected to form a neutral point of the static synchronous compensator, and the other ends of the three phases of the cascading units are connected into a three-phase grid through the corresponding connection reactors and the corresponding breakers. The invention further provides a corresponding cascading unit. An STATCOM and a BESS are combined, the capacity of controlling active power and reactive power at the same time is achieved, grid connection of medium voltage and high voltage is achieved in a manner of cascading multiple cascading units, a power switch device which is low in voltage resistance is used for achieving energy conversion of high voltage levels, modularization and redundancy design are easy to achieve, the function of balancing a battery is achieved, meanwhile, a bidirectional DC / DC converter is introduced at the direct current side, and ensuring the cycle life of the battery is facilitated.

The invention relates to Internet of things-based intelligent high-voltage switch cabinet. The Internet of things-based intelligent high-voltage switch cabinet comprises a high-voltage switch cabinet, and is characterized by comprising a sensor module, a radio frequency identification (RFID) module, a control mechanism, an on-site monitoring unit and an intelligent processing unit. In the Internet of things-based intelligent high-voltage switch cabinet, the conventional high-voltage switch cabinet is designed, so that the high-voltage switch cabinet is combined with intelligent unit; therefore, the intelligence of the high-voltage switch cabinet is realized in the true sense. The Internet of things-based intelligent high-voltage switch cabinet not only has the functions of the conventional high-voltage switch cabinet, but also has the functions of self-monitoring, self-diagnosis, self-action and the like.

The invention provides a novel high-voltage direct current power supply system structure applied to a data center. The novel system structure is characterized in that a high-voltage direct current on-line mode and a high-voltage direct current off-line mode are combined, the power receiving compatibility of IT equipment is fully considered, the compatible structure is flexible, and more practical significance is achieved; the check discharge test function of a storage battery in the on-line mode is optimized, detection precision is improved, and meanwhile damage to the storage battery due to large-capacity discharging is reduced; a storage battery testing bus is added to the system, and the problem of the periodic inspection of the storage battery in the high-voltage direct current off-line mode is simply solved; a bidirectional transducer is used, and the charging and discharging control of the storage battery is more flexible; the using of a rectifier module is reduced in the off-line mode, system efficiency is improved, and input cost at an earlier stage is lowered.

The invention relates to the field of electric vehicles, particularly to an electric quantity control device and method of a hybrid energy storage system electric vehicle. The control device comprises connecting a diode and a contactor between a lithium battery and a super capacitor, and the breakover direction of the diode is that electricity can only flow from the battery to the super capacity. The control device also comprises a sensing device for collecting various states of the electric vehicle and a control system which can control various parts of the electric vehicle according to information transmitted by the sensing device, wherein the sensing device collects various states of an engine in real time and transmits the states to the control system, and the control system compares and judges the states with preset values to control various parts to work and accordingly achieve electric quantity control. The electric quantity control device of the hybrid energy storage system electric vehicle can reasonably distribute the electric quantity of an energy storage system and an APU (auxiliary power unit) system to enhance the integral dynamic performance, improve the comprehensive fuel saving rate and reduce the energy consumption and discharging, and meanwhile, prolong the service life of the power battery and improve the electricity efficiency and the operating reliability of the power battery.

The invention comprises an internal combustion engine, a torsional vibration damper, two epicyclic trains, two motors, two driving shafts, a casing and a clutch. The internal combustion engine is connected with the planetary frame of the first epicyclic train through the torsional vibration damper and the first driving shaft the first motor is connected with the solar wheel of the first epicyclic train and the second motor is connected with the solar wheel of the second epicyclic train. The annular gear of the first epicyclic train is connected with the planetary frame of the second epicyclic train through the second driving shaft. The clutch drive disk is connected with the first driving shaft and the clutch driven disk is connected with the second driving shaft or the rotor of the first motor.

The invention relates to the field of photovoltaic driving control, in particular to a single-stage type photovoltaic water pump control system and method solving the problems that a photovoltaic frequency converter of a traditional photovoltaic water pump system is complex in structure and high in control cost. An inversion frequency converter of the single-stage type photovoltaic water pump control system is an energy level, the direct current change link in the traditional photovoltaic water pump frequency converter is structurally removed, and the maximum power tracking and energy buffering functions in the original direct current converting link are achieved through the control function. The condition that the frequency disturbing method is adopted to carry out photovoltaic output to a water pump motor to output energy in control is utilized, and therefore maximum power output and stable system operation can be met. The control method is used for controlling the system frequency f, and priority is given to the maximum photovoltaic side power tracking method for frequency control. The frequency f is approximately in direct proportion with the revolving speed of the motor, the cube of the revolving speed of the motor is in direct proportion with the output power P of a load water pump, the frequency is adjusted, transmission power control can be achieved, and therefore a photovoltaic part can be output with maximum power.

The invention provides an electric adjusting power divider with a filter function. The entire circuit structure of the electric adjusting power divider is symmetric, and the power dividing ratio is 1:1. Two pairs of quarter-wave resonators which are coupled with each other form two filter networks, and the characteristic of band-pass filtering is achieved. The matching of three ports of a circuit and the isolating of two output ports of the circuit are achieved by resistors. According to an on-load variable capacitance diode, the electrical length of the resonators and the electrical length of a feeder line are adjusted by changing the on-load voltage of the on-load variable capacitance diode, and the purpose that the center frequency is adjustable is achieved. In addition, three transmission zeros are introduced by source load coupling, so that the electric adjusting power divider has high selectivity and is also good in stopband suppression effect.

The invention discloses construction machinery, a control system and a control method thereof. The control system comprise an input device, a control device and an output device, wherein the input device acquires preset parameters; the control device obtains preset operation parameters according to the preset parameters and generates control signals according to the preset operation parameters which comprise a preset operation parameter of a prime mover and a preset operation parameter of a hydraulic system; the output device outputs the control signals generated by the control device; and the control signals comprise a control signal of the prime mover and a control signal of the hydraulic system. because of preset operation parameters obtained by the control device from the whole construction machinery according to the preset parameters, the power match among the prime mover, a hydraulic pump and a hydraulic execute component can be realized, the energy consumption of the whole construction machinery is lowered and the operation efficiency of the construction machinery is improved.

The invention discloses a realization circuit and a realization method of a constant current and a constant power. The realization method comprises the following steps of: sampling an output current of a load R0 to acquire an output current sampling value; inputting the current sampling value, a constant current set value and a constant power set value to an A / D sampling port of a controller; when the constant value set value is greater than or less than the output current sampling value, sending a control signal by the controller so as to control a PWM drive chip to increase or decrease a duty cycle of a PWM signal output by the PWM drive chip, thereby realizing the constant current on the load R0; or calculating a power sampling value on the load R0 by using the output current sampling value, when the constant power set value is greater than or less than the power sampling value, sending a control signal by the controller to control the PWM drive chip to increase or decrease the duty cycle of the PWM signal output by the PWM drive chip, thereby realizing the constant power on the load R0. According to the realization circuit and the realization method of the constant current and the constant power disclosed by the invention, a current sampling element, such as a diverter, a Hall sensor or a mutual inductor, is not needed; moreover, the realization circuit and the realization method have the advantages of simple structure of the circuit, low realization cost, and the like.

The invention discloses a non-uniform power divider with an integrated band-pass filtering function. The non-uniform power divider comprises an upper-layer micro-strip structure, an isolating element, a middle-layer medium substrate and a lower-layer grounding metal plate. The non-uniform power divider with the integrated band-pass filtering function comprises two single-frequency band-pass filtering circuits and the isolating elements connected between the two single-frequency band-pass filtering circuits. Input impedance and output impedance of the non-uniform power divider are identical, and input impedance and output impendence of each single-frequency band-pass filtering circuit can be regulated by changing coupling strength among corresponding resonators and positions of corresponding ports, so that power can be divided according to different ratios, and matching can be realized. A quarter-wave impedance conversion section required at an output port of the traditional Wilkinson non-uniform power divider can be omitted, so that the size of the non-uniform power divider is effectively reduced. The non-uniform power divider can be used in various radiofrequency front-end systems, has a power dividing function and a frequency selecting function, and is beneficial to integrating and minimizing devices.

The invention discloses a three-port DC converter and belongs to the technical field of power electronic converters. The three-port DC converter consists of an input DC source, a storage battery, a primary side circuit, a secondary side circuit, and a transformer. The primary side circuit is connected with the input DC source and the storage battery simultaneously; the secondary side circuit is connected with load; and the primary side and secondary side are in electrical isolation through the transformer. The three-port DC converter is characterized in that: due to a converter, the power management and control of a main power supply, the storage battery, and the load is realized, and the functions of a plurality of single-input single-output converters are realized; and compared with a mode of adopting a plurality of single-input single-output converters, the three-port DC converter has the advantages of reducing the number of switching devices and related control circuits, improving the conversion efficiency, simplifying the control circuit, achieving high reliability, adopting more compact layout and unified and effective management, improving the system stability, reducing the system cost, reducing the volume, and improving the power density.

The invention discloses a compressor control method. The compressor control method comprises the steps of acquiring compression status information, based on the status information, determining the compressor current status, when the compressor is in a power pre-protection status, based on the current status, determining a rotation speed regulating mode, based on the determined rotation speed regulating mode, regulating the compressor rotation speed. The compressor control method can use different speed regulating modes for different over-power situations to achieve the power protection, and avoids the compressor damage. The invention further discloses a compressor control device and a refrigerator.