323 results about "Three-phase" patented technology

The invention provides a platform area power grid tail end voltage flexible regulation and control method and system. The method comprises the steps that a sampling module measures common coupling point voltage at the tail end of a platform area power grid; the impedance calculation unit obtains load end impedance; the current calculation unit calculates the current of the common coupling point through the voltage of the common coupling point and the impedance of the load end; the current resolving unit is used for resolving the common coupling point current into negative-sequence current and zero-sequence current; the compensation current unit calculates a compensation current component required for maintaining the stability of the voltage at the tail end of the transformer area power grid through the negative-sequence current and the zero-sequence current; the PWM unit generates a compensation current control signal; and the IGBT module outputs compensation current to the common coupling point. When three phases are unbalanced, the first disturbance generation circuit accurately injects a disturbance signal to effectively regulate and control the voltage at the tail end of a power grid in a transformer area; and the second disturbance generation circuit analyzes the stability of the tail end of the station area power grid by using coordinate transformation and a PI controller.

The invention discloses a power regulation method and device and energy storage equipment, which are applied to a transformer area, the transformer area comprises three phase lines A, B and C and at least one energy storage equipment, each energy storage equipment is respectively connected with the three phase lines, the energy storage equipment is used for regulating and controlling the voltage of the phase lines, and for each phase line connected with any energy storage equipment, the voltage of each phase line is regulated and controlled. The method comprises the steps of determining a voltage deviation value of a phase line based on a first voltage value and a reference voltage value of the phase line at a current sampling moment; obtaining a first output power and a power adjustment step length of the energy storage device at a previous sampling moment, wherein the power adjustment step length is a power adjustment value used when the first output power is generated at the previous sampling moment; and determining second output power of the energy storage equipment at the current sampling moment based on the power adjustment step length, the first output power and the voltage deviation value. The technical problem of how to adjust the energy storage system to stabilize the voltage of the transformer area when the voltage of the transformer area is in an unstable state is solved.

The invention discloses a modular alternating support current converter without a bridge arm inductor and a modulation method thereof, and relates to the technical field of power electronics. According to the modular alternate support converter, a new modular alternate support converter topology is provided by reconstructing an operation mode of a traditional MMC, and the modular alternate support converter comprises three phase units; each phase unit comprises an upper bridge arm and a lower bridge arm which are connected in series; each bridge arm comprises N submodules which are connected in series; two ends of each phase unit serve as positive and negative poles of a direct-current end; the midpoint of the phase unit is connected with an AC filter inductor as a connecting end of three-phase power; the anode of the DC end is provided with a DC filter inductor. According to the modularized alternating supporting converter, a filter inductor does not need to be additionally arranged on a bridge arm, the modularized alternating supporting converter has the large capacity reduction amplitude and power density, the size is small, the power density is high in the corresponding alternating operation mode, the engineering implementation difficulty is low due to the full-modularized design, and good economical efficiency is achieved.

The invention relates to a single-loop control method for a static synchronous phase modifier, which belongs to the technical field of power systems, and comprises the following steps of: comparing a maximum voltage difference value in three phases with a preset voltage threshold value to obtain a voltage difference value after amplitude limiting, and obtaining a first virtual reactance by using the voltage difference value after amplitude limiting and a preset current amplitude limiting threshold value; performing proportional integral control on the difference between the maximum current value in the three phases and the current amplitude limiting threshold to obtain a second virtual reactance; virtual impedance is calculated according to the first virtual reactance and the second virtual reactance; the product of the virtual impedance and the current of each phase is used as the current amplitude limiting voltage of the corresponding phase; the modulation wave of the corresponding phase is generated by using the internal potential and the current amplitude limiting voltage of each phase, so that the voltage single-loop control and the fault current amplitude limiting of the static synchronous phase modifier are realized, the broadband oscillation risk and the overcurrent risk of the converter are effectively reduced, and the safety and the reliability of static synchronous phase modifier equipment are improved.

The embodiment of the invention provides a transformer no-load closing angle control method, electronic equipment, a storage medium and a program product. The method comprises the following steps: periodically sampling three-phase voltages at a power supply side of a transformer, and determining a zero crossing moment when the phase voltage is changed from a negative value to a positive value according to respective sampling data for each phase in the three phases; based on the zero point moment of each phase, a preset switching-on angle and the total delay required from the switching-on instruction sending to the actual conduction of the main circuit, the target moments at which the switching-on instructions of the three phases should be sent out are calculated respectively, and corresponding switching-on trigger signals are output at the target moments of the phases respectively; and in response to the closing trigger signal of each phase, combined switch circuits arranged in the three-phase line are respectively driven, and each group of combined switch circuit comprises an MOS (Metal Oxide Semiconductor) tube and a dry reed relay which are connected in parallel, so that the MOS tube is conducted to establish an initial current path.

A power module, for power electronics of a vehicle, having two DC busbars and three phase busbars which are disposed between the two DC busbars, and a plurality of power semiconductors, each of which is disposed between one of the DC busbars and one of the phase busbars, and power electronics having at least one such power module, and a vehicle having such power electronics. The DC busbars and the phase busbars are electrically insulated from one another and in each case have at least one cooling duct through which a dielectric fluid flows, at both open ends each of the DC busbars and the phase busbars having at least one plug-in electrical contact connection and at least one plug-in fluid connection that in each case form a combined plug-in connection, so that multiple power modules are connectable to each other in fluid-tight fashion using plug connections.

The invention discloses a method and a system for diagnosing defects of a sheath grounding system under resonance voltage resistance of a power transmission cable. The method comprises the following steps: installing a sheath grounding current acquisition system; sequentially carrying out main insulation resonance voltage withstanding tests on three phases of the power transmission cable, and synchronously recording a grounding current waveform of a metal sheath by adopting a current acquisition system when each phase is subjected to voltage withstanding; processing the grounding current waveform by adopting a signal processing algorithm, and extracting a resonance component; and constructing a defect diagnosis matrix according to the resonance component, calculating a deviation between the defect diagnosis matrix and a standard matrix as a defect characterization value of the cable sheath grounding system, and obtaining a defect diagnosis conclusion of the sheath grounding system under the resonance withstand voltage of the power transmission cable. According to the method, the grounding current waveform of the metal sheath is synchronously acquired and analyzed in the main insulation resonance voltage withstand test of the three-phase cable, the resonance component is extracted, accurate identification of the defect is realized based on deviation calculation of the defect diagnosis matrix, and the detection sensitivity and the diagnosis reliability of the latent defect of the sheath grounding system before the cable is put into operation are improved.

In a case where three-phase coils are wound with a conductor around twelve magnetic pole teeth that are provided at equal angular intervals on an inner peripheral portion of a stator core forming a three-phase, twelve-pole stator, the winding configuration is such that the windings of the respective three phases share a first common winding pattern of the conductor around the magnetic pole teeth but differ in their circumferential positions on the stator core, and each phase winding includes a first portion and a second portion that share a second common winding pattern of the conductor around the magnetic pole teeth but differ in their circumferential positions on the stator core by half a circumference. The conductor is wound simultaneously for all of the first and second portions of the three phases by synchronously moving six nozzles feeding the conductor, relative to the stator core.

Electrical apparatus (20) includes an inverter (24) having input terminals for receiving DC input power and output terminals for coupling to an AC power grid. A pulse-width modulation (PWM) generator and drivers (26) drive the switches so as to control respective amplitudes, frequencies, and phases of the output current waveforms of the inverter. Control circuitry (28) receives measurements of respective time-varying voltages and currents on the input and output terminals, computes a model (40) that includes three virtual currents flowing in a synchronous machine that is emulated by the apparatus, wherein the three virtual currents are associated respectively with the three output current waveforms, and controls the PWM generator and drivers responsively to the three virtual currents so as to synchronize the amplitudes, frequencies, and phases of the three output current waveforms of the inverter with the three phases of the AC power grid.

A power storage system has a battery, a three-phase motor in which coils of three phases are connected at a neutral point, an inverter connected on an electric power transmission path between the battery and the three-phase motor, and a DC power supply circuit connected to a connection portion positioned on an electric power transmission path between the inverter and the battery. The battery includes two power storages and a switch unit that switches between a first voltage state where the two power storages are connected in series and chargeable at a first voltage, and a second voltage state where the two power storages are connected in parallel and chargeable at a second voltage. The DC power supply circuit has a branch circuit connected to a coil of any one phase among the coils of three phases at a positive electrode side of the DC power supply circuit.

The utility model relates to the technical field of high-voltage cascade energy storage systems, and discloses a valve hall type high-voltage cascade energy storage system based on nested power modules, which comprises three phases of chain type energy storage bridge arms respectively connected with three phase lines of a power grid, and each phase of chain type energy storage bridge arm comprises a plurality of cascaded nested power modules. Each nested power module comprises a plurality of direct-current energy storage units and an H-bridge circuit, the plurality of direct-current energy storage units are connected in parallel and then connected with the direct-current side of the H-bridge circuit, and the alternating-current side of the H-bridge circuit is connected with an alternating-current switch; the DC energy storage unit comprises a battery cluster and a DCDC converter connected with the battery cluster in parallel, the DCDC converter comprises a first capacitor, a second capacitor and a power conversion unit, and the power conversion unit comprises three full-control semiconductor devices and an inductor. According to the utility model, each battery cluster is accurately controlled through the DCDC converter in the embedded power module, so that the reliability of the valve hall type high-voltage cascade energy storage system is improved.

A system for efficiently generating or originating a tailored electromagnetic (EM) wave having a lower velocity than the speed of electromagnetic waves in free space includes a coaxial waveguide which extends linearly and a sinewave current generator. The coaxial waveguide includes a tubular outer body and a tailored emitting antenna disposed coaxially within the tubular outer body. The tubular outer body is formed of a first conductive material and defines a space therein which may be maintained as vacuum. The tailored emitting antenna is constructed physically and electrically by at least three phase-shifted sub-antennas connected in series, each of the sub-antennas being formed of a second conductive material which is less conductive than the first conductive material. The sinewave current generator generates multiple phase-shifted sinewave currents which are respectively input to the sub-antennas.

Provided is an electric-power conversion apparatus including respective arms of three phases each having switching devices that are connected with a DC power source and an external connection point that is connected with a winding of an electric rotating machine. A phase current detection unit detects a current of each of the three phases, and a switching control apparatus that controls the electric rotating machine by turning on or off the positive-polarity switching devices and the negative-polarity switching devices and that determines that an excessive current has occurred, in the case where a current detected by the phase current detection unit exceeds a predetermined threshold value, and then turns on any one of a group of all the positive-polarity switching devices and a group of all the negative-polarity switching devices and turns off the other one thereof.

To provide a partial discharge detection system targeting a power receiving / distributing apparatus.SOLUTION: A partial discharge detection system of a power receiving / distributing apparatus includes: a control device housing a plurality of power devices such as a breaker and a disconnector within a grounded metal case and configured to control / monitor the plurality of power devices; and a partial discharge sensor dependent on an electromagnetic wave. The partial discharge detection system is configured to: measure a voltage of one phase among three phases as a reference phase; calculate the number of times by which an output of the partial discharge sensor dependent on an electromagnetic wave enters a range of a phase angle of a preset voltage; and determine a phase corresponding to a range of a phase angle reaching a prescribed number of times or more as a phase at which a partial discharge is occurring.SELECTED DRAWING: Figure 1

This application discloses a power supply circuit based on a three-phase power supply, and a method for simultaneously achieving power factor tracking and dynamic boost / buck conversion. The power supply circuit includes an information acquisition module and a power supply circuit unit, the power supply circuit unit includes three circuit groups formed by three phases connected to a three-phase power supply, and a control center for controlling the operating state of the three circuit groups. Each circuit group includes an input rectifier module, inductor, capacitor, switch and its controller, transformer, and output half-wave rectifier module. The output terminals of the three circuit groups included in the power supply circuit unit are connected in parallel or in series to solve the ripple problem and improve power conversion efficiency. The aforementioned power supply circuit adjusts the peak value of the input current at a high frequency, further adjusting the switching frequency and duty cycle, and controlling the charging and discharging time of the inductor to achieve power factor tracking, while simultaneously enabling dynamic adjustment of boost and buck voltage to meet load demands, effectively reduce costs, have low energy loss, and have high power conversion efficiency.

The utility model relates to the technical field of motor internal winding temperature measurement, in particular to a motor wiring terminal temperature measurement circuit, which comprises a first driving unit, a second driving unit, a temperature sensor, a main control unit, three first switch tubes and three second switch tubes, the temperature sensor is tightly attached to the outer wall of a phase line of the motor, one end of the source electrode of each first switch tube electrically connected with the drain electrode of the corresponding second switch tube is correspondingly and electrically connected with one phase line of the motor, and the temperature sensor is used for collecting the temperature of the three phase lines of the motor and transmitting the collected temperature to the main control unit; the main control unit outputs signals to the first driving unit and the second driving unit, the first driving unit transmits the signals to the three first switch tubes, and the second driving unit transmits the signals to the three second switch tubes, so that the motor is driven to operate. Meanwhile, the motor can be driven to operate.

A distributed ice melting device topological structure suitable for an ultra-high voltage power transmission line comprises a plurality of ice melting sub-modules arranged in a distributed mode, and each ice melting sub-module comprises a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge current converter and a direct-current capacitor. A primary winding of the single-turn coupling transformer is directly formed by split sub-conductors of the ultra-high voltage power transmission line, and a secondary winding of the single-turn coupling transformer is electrically connected with other parts of the ice melting sub-modules, so that the ice melting sub-modules are connected in series on the split sub-conductors of the power transmission line in a distributed manner; the H-bridge current converter is electrically connected with the direct-current capacitor, and the direct-current capacitor provides smooth direct-current voltage for the H-bridge current converter; the filter is connected in series with the H-bridge current converter, the bypass switch is connected in parallel with the H-bridge current converter, and the metal oxide voltage limiter is connected in parallel with the line side output end of the ice melting sub-module; and the ice melting sub-modules adjust the current of the corresponding split sub-conductors by changing the equivalent impedance of the ice melting sub-modules, so that accurate ice melting of the ice-coated split sub-conductors is realized, and the overall current and the transmission power of the power transmission line are kept unchanged. The technical problem to be solved by the invention is to provide the distributed ice melting device topological structure suitable for the ultra-high voltage power transmission line, and the technical problem that the existing ice melting technology cannot realize accurate ice melting and non-power-cut operation on an ice coating section on the ultra-high voltage power transmission line is solved. And normal transmission of the line is affected due to overlarge capacity demand, line overcurrent or incapability of three-phase synchronous ice melting.

The invention discloses a station AC system residual current monitoring method and system, and the method comprises the steps that a cloud server receives current signals transmitted by a monitoring field mobile terminal, and the current signals comprise current signals of three phase lines and a neutral line; correcting the current signal based on the deviation variation trend of the historical measurement result of the residual current sensing equipment; performing vector synthesis based on the corrected current signals of the four lines to obtain a residual current signal; and extracting a feature vector based on the current residual current signal, and analyzing whether a fault occurs and the type of the fault based on the feature vector. According to the invention, the mobile terminal and the cloud end are combined to realize residual current monitoring, the accuracy and efficiency of residual current monitoring analysis are improved, and the cloud end is utilized to analyze the fault of the residual current signal to realize the monitoring of the electrical safety of the line.

The utility model relates to a stator, and belongs to the technical field of motors. A plurality of winding groups of the stator are sequentially connected end to end from the first winding group to the last winding group, and winding assemblies for three-phase winding are arranged on the winding groups; the last winding group is also provided with a first connecting block and a second connecting block, the tail ends of the first phase and the second phase in the three phases are connected to the first connecting block, the tail section of the third phase in the three phases is connected to the second connecting block, one end of the neutral point connecting assembly is connected with the first connecting block, and the other end of the neutral point connecting assembly is connected with the second connecting block. The other end of the neutral point connecting assembly is connected with the second connecting block, and the neutral point connecting assembly can conduct electricity; the first connecting piece and the second connecting piece are connected through the neutral point connecting assembly, so that the tail ends of the three-phase coils are connected to form a neutral point, common point enameled wires are separately welded, paint film removal is facilitated, the tinning difficulty of the enameled wires is reduced, the welding qualification rate of an automatic production line is improved, and the product quality risk is reduced.

The flat wire motor stator winding comprises a first coil assembly and a second coil assembly, the first coil assembly and the second coil assembly are the same in structure, the first coil assembly and a coil are combined to form the new stator winding, the first coil assembly and the second coil assembly are mutually independent and not connected, and conductors of the first coil assembly and the second coil assembly share a slot. The conductor of the coil group I and the conductor of the coil group II share the same slot and are arranged in pairs at intervals, the electric phase angle difference is 0 degree, the conductor of the coil group I and the conductor of the coil group II share the slot, the conductor of the coil group I and the conductor of the coil group II are arranged in pairs at intervals, the electric phase angle difference is 0 degree, the conductors of the two coils in the slot are circumferentially arranged according to U1, U2, W1, W2, V1 and V2, U1, V1 and W1 are three phases of the coil group I, and U2, V2 and W2 are three phases of the coil group II. The coil assembly I and the coil assembly II are combined, the structures of the two coil assemblies are completely the same, the variety of hairpins is few, the difference between wire outlet positions in the circumferential direction is 180 degrees, the phase difference is 0 degree, and independent control and parallel control can be achieved.

The application discloses a kind of station with alternating current system residual current monitoring method and system, the method includes: cloud server receives the current signal sent by monitoring field mobile terminal, the current signal includes the current signal of three phase lines and one neutral line;Based on the deviation change trend of historical measurement results of residual current sensing device, correct current signal;Based on the current signal of four lines after correction, vector synthesis is carried out, and residual current signal is obtained;Based on current residual current signal, extract feature vector, based on feature vector analysis whether fault occurs and the fault type that occurs.The application uses mobile terminal and cloud to jointly realize residual current monitoring, improve the accuracy and efficiency of residual current monitoring analysis, uses the fault analysis of residual current signal by cloud, realizes the monitoring of line electrical safety.

A bidirectional DC-DC conversion apparatus and a charging pile. The bidirectional DC-DC conversion apparatus includes a first power conversion circuit, a second power conversion circuit, a three-phase transformer, three phase resonant circuits, a resonant switching switch circuit, and an inductor circuit. Each phase of resonant circuit includes a first capacitor and a first inductor that are connected in series. One end of each phase of resonant circuit is connected to the first power conversion circuit, and the other end of each phase of resonant circuit is connected to the second power conversion circuit via the three-phase transformer. The resonant switching switch circuit is configured to connect a circuit between either of two ends of each phase of resonant circuit and the inductor circuit to enable each phase of resonant circuit and the inductor circuit to form an LLC resonant circuit.

The invention discloses a high-power compressor driving circuit, a high-power compressor and a control method of the high-power compressor. The high-power compressor driving circuit comprises a controller, a three-phase half-bridge driving circuit, a three-phase half-bridge circuit and a direct current-direct current converter, the three-phase half-bridge driving circuit is connected with the controller; the three-phase half-bridge drive circuit is connected with the three-phase half-bridge circuit; the DC-DC converter is connected with the controller and the three-phase half-bridge drive circuit. Wherein the three-phase half-bridge circuit comprises 12 insulated gate bipolar transistors, each phase of the three phases of the three-phase half-bridge circuit comprises 4 insulated gate bipolar transistors, and the three-phase half-bridge circuit is used for driving the permanent magnet synchronous scroll compressor connected with the three-phase half-bridge circuit. The permanent magnet synchronous scroll compressor connected with the three-phase half-bridge circuit is driven in a double-tube parallel current expansion mode corresponding to the three-phase half-bridge circuit, the full-load load power of the permanent magnet synchronous scroll compressor can meet the driving refrigeration requirement of large equipment, the on-load overcurrent capacity is enhanced in the double-tube parallel current expansion mode, and the influence of the environment temperature is reduced.

The invention belongs to the technical field of line fault judgment, and particularly relates to a high-voltage line short-circuit fault judgment test method. The method comprises the following steps: checking and determining tripping of a certain high-voltage feed-out line; line-to-overhaul full discharge is realized; switching the resistance gear of the universal meter to a * 1 gear, and respectively measuring the inter-phase resistance of the three phases of the fault line; during measurement, if the pointer of the universal meter instantly deviates to zero, it shows that a short-circuit fault exists in the line; if the pointer of the universal meter begins to swing rightwards, gradually slows down after reaching the middle and finally deviates to zero, and the whole test process is short, the line has no short-circuit fault; according to the swing condition of the pointer of the universal meter, whether the current line has a short-circuit fault can be judged. According to the invention, the problems of low power transmission efficiency caused by too long fault processing time due to the fact that line lightning trip-out faults need to be checked by an external line electrician and fault points need to be found by disconnecting the user side incoming line disconnecting switches one by one during troubleshooting are solved.

The invention relates to a method for heating a high-voltage battery (2) of a high-voltage system (1) of an electrically powered vehicle, wherein the high-voltage system (1) comprises an inverter (4) and at least one capacitor (C_X1, C_X2) in an intermediate circuit, wherein the inverter (4) has two high-voltage potentials (P+, P-) as DC voltage terminals and three phase terminals to which an electric machine (3) is connected, wherein the inverter (4) has a plurality of semiconductor switches (S1 to S12), wherein energy is transferred between the high-voltage battery (2) and the at least one capacitor (C_X1, C_X2) using the semiconductor switches (S1 to S12), the at least one capacitor (C_X1, C_X2) and the motor inductances (L1, L2, L3) of the electric machine (3), wherein the inverter (4) is designed as a 3-level inverter, and wherein the intermediate circuit is a series connection of two Capacitors (C_X1,C_X2) with a center tap (M) connected to the inverter (4), wherein energy is alternately transferred between the two capacitors (C_X1, C_X2) using the semiconductor switches (S1 to S12) of the inverter (4) in order to cause a correspondingly reversing current flow between the high-voltage battery (2) and the capacitors (C_X1, C_X2) and thus to heat the high-voltage battery (2).

A motor control device, a motor control method, and a motor unit control a brushless motor including a rotor and three-phase armature coils, the motor control device including: a position detection section that detects a rotational position of the rotor; a control section (54) that outputs first or second drive signals to an inverter (52) in a first or second control mode with a current application timing corresponding to the rotational position of the rotor; and the inverter (52) that outputs first or second current application signals to the three-phase armature coils when the first or second drive signals are input, in the second control mode, a value of a duty cycle at which a voltage is applied simultaneously to any two phases of the three phases is greater than in the first control mode.

This invention proposes a method, device, storage medium, and variable frequency air conditioner for detecting reverse connection of phase and neutral wires. The detection method is used in the three-phase rectifier circuit of the variable frequency air conditioner. The three-phase rectifier circuit includes a neutral wire, a DC bus, three phase wires, and a first relay, a second relay, and a third relay located on each phase wire. The detection method includes: acquiring a first voltage value of the DC bus when all three relays are closed; acquiring the current voltage value of the DC bus when any relay is open; and determining that one phase wire is reverse connected to the neutral wire when the first voltage value is not equal to the current voltage value. In this invention, there is no need to set up a separate three-phase detection circuit in the power supply circuit of the variable frequency air conditioner. The connection status of the phase and neutral wires can be determined using only the existing three-phase rectifier circuit of the variable frequency air conditioner, facilitating the miniaturization and weight reduction of the power supply circuit of the variable frequency air conditioner.

Control device applied to an electric power steering device to assist a driver's steering operation, comprising: - a rotating electrical machine (10, 210) with a stator (12, 212) with a first winding group (13) and a second winding group (14) which are wound onto the stator in at least three phases, a rotor (15) which is rotatably arranged with respect to the stator, and a shaft (16) which rotates together with the rotor; - a substrate (41, 241, 341, 351, 355) that is arranged at an axial end of the rotating electrical machine; - a first control element (51-56) which (i) is arranged on a surface (42, 242, 342) of the substrate (41) in a first region (R1) and (ii) forms a first inverter (50) which switches a power supply to the first winding group; - a second control element (61-66) which (i) is arranged on the same surface of the substrate as the first control element in a second region (R2) and (ii) forms a second inverter (60) which switches a power supply to the second winding group, wherein the second region (R2) is symmetrical to the first region (R1) with respect to a shaft of the rotating electrical machine; - a first connecting line (135) extending from each of the at least three phases of the first winding group to be connected to the substrate; and - a second connecting line (145) extending from each of the at least three phases of the second winding group to be connected to the substrate, - wherein the first connecting line and the first control element, as well as the second connecting line and the second control element, each have reversed phase sequences in an arrangement of phase sequences from one end near a reference position to another end of the arrangement, such that magnetic leakage flux and variation in wiring impedance among the at least three phases are reduced, - wherein the reference position has an electrical energy supply area (Rin) which is (i) an area outside the first area (R1), the second area (R2) and a control element area (R3) which has a central axis (O) of the rotating electrical machine, and (ii) an area with a circuit pattern which supplies electrical energy from a battery (109) to the first and second inverters.

The utility model discloses an alternating-current variable-frequency power supply capable of realizing three-phase-to-single-phase full-power output, which comprises a main board, a slow starting module, a three-phase EMI (Electro-Magnetic Interference) filter, an R-phase output isolation transformer, an S-phase output isolation transformer, a T-phase output isolation transformer and a three-to-single interlocking switching contactor, the main board is provided with an output voltage sampling end pin, an output current sampling end pin, an SPP-107, an operation panel removing end pin, a driving signal end pin and a slow start removing end pin, and the main board is connected with the slow start module through the slow start removing end pin. The power supply does not need to additionally purchase single-phase power supply equipment and can be directly switched; compared with a voltage regulator scheme, a variable-frequency power supply is used for supplying power and is isolated from a mains supply power grid, so that the anti-interference performance is improved; an interlocking mechanism is arranged between the single phase and the three phases, so that the single-phase output and the three-phase output are prevented from being mistakenly connected, and the tested equipment is prevented from being damaged.

This application discloses a soft-start method, apparatus, device, and storage medium for a three-phase LLC converter. The soft-start method includes: responding to a start command, pre-charging the three phases of the three-phase LLC converter in a preset sequence; after the three phases have completed pre-charging, performing coordinated linear modulation on the duty cycle and frequency of the three phases so that the duty cycle of each phase approaches a preset target duty cycle, and the frequency of each phase approaches a preset target frequency; and controlling the three-phase regulated output when the duty cycle of each phase reaches the preset target duty cycle and the frequency of each phase reaches the preset target frequency. This application can achieve more stable and safer three-phase soft starting.