523 results about "Isolation transformer" patented technology

The invention relates to the technical field of hybrid inverters, and discloses a hybrid inverter supporting reactive compensation and a control method thereof, and the hybrid inverter comprises a DC input unit, a three-phase full-bridge inversion unit, a grid-connected switching unit, a signal acquisition unit and a digital control unit. The direct current input unit comprises a photovoltaic interface, a battery interface and a direct current bus and is used for converging photovoltaic and energy storage electric energy; the three-phase full-bridge inversion unit is composed of a power device and an LCL filter and converts direct current into alternating current. The grid-connected switching unit comprises a static switch and an isolation transformer and is used for controlling power grid connection; the signal acquisition unit detects voltage and current signals; and the digital control unit judges a grid-connected mode or an off-grid mode according to the signal, calculates a reactive current reference value and generates a PWM (Pulse Width Modulation) control signal so as to realize reactive compensation control in the grid-connected mode and the off-grid mode. According to the invention, reactive power compensation capability is provided in both grid-connected and off-grid operation modes, and stable operation of the inverter in various working conditions is ensured.

The invention belongs to the field of power transmission line parameter measurement, and discloses a live-line testing device and method for mutual inductance line parameters and zero-sequence impedance parameters. The device comprises a double-circuit line simulation module, a pilot frequency excitation module, a power frequency simulation module, a synchronous acquisition module and a signal processing module. The isolation transformer simulates a double-circuit line, the pilot-frequency power supply provides pilot-frequency excitation signals, the measurement unit realizes synchronous acquisition, and the signal processing module performs anti-interference and amplification processing. The method comprises the steps of line simulation wiring, synchronous time synchronization, pilot frequency signal acquisition, parameter calculation and error verification, and pilot frequency parameters are converted into power frequency parameters by using a frequency conversion formula. According to the invention, power frequency interference can be effectively suppressed in a charged environment, high-precision measurement of zero-sequence impedance and mutual inductance parameters of a mutual inductance line is realized by using pilot frequency excitation and Beidou synchronization technologies, the measurement error is remarkably reduced, the safety and reliability are remarkably improved, and powerful technical support is provided for safe and stable operation of a power system.

The utility model discloses a soft start system based on excitation current reduction, which is characterized in that a time relay mainly controls the switching of a live wire between a power resistor and an alternating current contactor, the power resistor magnetizes a transformer at the moment of electrification, and the alternating current contactor is connected into a circuit by the time relay after the magnetization is completed; and after the power resistor is short-circuited, the circuit is cut out, so that the purpose of suppressing the excitation inrush current is finally achieved, the excitation effect caused by voltage abrupt change at the power-on moment of the isolation transformer can be avoided, and the excitation abrupt change of the isolation transformer during power-on is effectively reduced.

The present disclosure relates to circuits for connecting components of a hydrogen plant to a power grid to power the components in an efficient manner. In one implementation, power-side alternate current (AC) to direct current (DC) converters may be connected to a source power grid without the need for an isolation transformer by providing separate buses between the power-side AC-DC converters and load-side DC-DC converters instead of a shared DC bus between the converters. Other implementations for connecting components of a hydrogen plant to a power grid may include an adjustable transformer, such as a tappable transformer or an autotransformer, to connect any number of auxiliary loads of the plant to the power grid. The adjustable transformer may provide for various types of auxiliary load devices to connect to the power provided by the transformer at the same time, including both three-phase devices and one-phase devices.

The invention discloses an FMQL20S-based navigation computer system and a software and hardware collaborative architecture, and relates to the field of computer systems. Comprising a programmable fusion chip JFMQL20S4841, a 1553B transceiver and isolation transformer 6, an ARINC429 transceiver 7, a self-isolation RS422 chip 8, a self-isolation RS232 chip 9, an RC resistance-capacitance filter 10, an RS422 first interface chip 11, an RS422 second interface chip 15, an RS422 third interface chip 16 and an RS422 fourth interface chip 17. The method is used for solving the prominent defects of high design cost, poor universality, time-consuming calculation, incapability of miniaturization and the like due to the fact that various performance indexes such as fusion of different sensors and calculation of a large amount of data need to be realized in the current navigation computer system design.

The invention relates to an expandable distributed voltage controller, and relates to the technical field of power grid electric energy management, the expandable distributed voltage controller comprises a series-parallel module comprising a parallel converter, a first series converter, a first DC capacitor and an isolation transformer, the DC side of the parallel converter is connected with the DC side of the first series converter through the first DC capacitor, and the DC side of the first series converter is connected with the isolation transformer through the isolation transformer; the alternating current side of the series converter is connected in series to the power grid side through the isolation transformer; and the series connection module comprises a second series connection converter, a second direct current capacitor and an isolation transformer, the second direct current capacitor is arranged on the direct current side of the second series connection converter, and the second series connection converter is connected to the load and / or the grid connection position in series through the isolation transformer. A plurality of problems can be solved while the power quality problem of the power grid is governed, so that the application range is wider.

A motor power source regulation circuit, a control method and an electronic device are provided. The motor power source regulation circuit includes a power factor correction circuit, an isolation circuit, a first power source conversion circuit, a second power source conversion circuit and a control circuit. The isolation circuit includes a first switch sub-circuit and an isolation transformer. The power factor correction circuit regulates an AC input signal to a first DC signal. The first switch sub-circuit converts the first DC signal to a first AC signal. The isolation transformer converts the first AC signal to two or more second AC signals. The first power source conversion circuit converts the second AC signal to a DC drive signal and outputs it to a DC motor. The second power source conversion circuit converts the second AC signal to an AC drive signal and outputs it to an AC motor.

The present disclosure relates to circuits for connecting components of a hydrogen plant to a power grid to power the components in an efficient manner. In one implementation, a power-side alternating current (AC) / direct current (DC) converter can be connected to a source power grid without the need for an isolation transformer by providing a separate bus between the power-side AC / DC converter and the load-side DC / DC converter, instead of a DC bus shared between the converters. Other implementations for connecting components of a hydrogen plant to a power grid may include an adjustable transformer, such as a tap-changing transformer or an autotransformer, for connecting any number of auxiliary loads of the plant to the power grid. The adjustable transformer may accommodate various types of auxiliary load devices for connecting to the power provided simultaneously by the transformer, including both three-phase and one-phase devices.

The invention discloses a hybrid distributed power flow controller topological structure and a control method thereof. The topological structure comprises a distribution network Sen transformer DST and a distributed static synchronous series compensator DSSC. The distribution network Sen transformer DST comprises a three-phase double-winding transformer and an on-load tap changer group; each phase of the three-phase double-winding transformer comprises a main winding and a secondary winding, the high-voltage end of the three-phase main winding is connected with the head end of the three-phase distribution line, the low-voltage end of the three-phase main winding is in star connection, and the neutral point of the three-phase main winding is grounded; the on-load voltage regulation switch group comprises six on-load voltage regulation switches which are respectively configured on the low-voltage side of the three-phase main winding and the three-phase secondary winding and provide three-phase first compensation voltage in a cross series connection mode; a distributed static synchronous series compensator DSSC provides a three-phase second compensation voltage; and the three-phase first compensation voltage and the three-phase second compensation voltage are superposed to synthesize a three-phase compensation voltage, and the three-phase compensation voltage is injected into a three-phase distribution line through a three-phase isolation transformer. The invention provides a series hybrid topology consisting of a DST (Digital Subscriber Terminal) and a DSSC (Digital Subscriber Subscriber Center).

The invention provides a vehicle-mounted charging circuit, a charging method and a charging system for an electric vehicle facing a 800V power battery, and relates to the field of manufacturing of related facilities of the electric vehicle, the circuit comprises a power factor correction module, a primary side power conversion module, a high-frequency isolation transformer, a bipolar charging module and a power battery equalization module; the input side of the power factor correction module is connected with an alternating current power grid, and the power factor correction module is used for rectifying alternating current into direct current; the primary side power conversion module is used for converting the direct current output by the power factor correction module into high-frequency alternating current; the high-frequency isolation transformer comprises at least two windings, and the two windings are connected with the primary side power conversion module and the bipolar charging module respectively; the bipolar charging module is connected with a 800V power battery, and the 800V power battery comprises two groups of 400V battery packs; the power battery equalization module is used for equalization management of two groups of 400V battery packs, and has the advantages of improving charging speed and efficiency of 800V power batteries and reducing equalization difficulty and cost.

The invention discloses an intelligent switching control electrician practical training identification device, which belongs to the technical field of electrical detection and comprises a practical training platform, an operation panel, an electrical carrier plate and a built-in PLC (Programmable Logic Controller), the system integrates power input, a first conversion unit composed of a first isolation transformer and a first contactor, a second conversion unit composed of a second isolation transformer and a second contactor, a control unit, a data storage module, an operation input unit, a feedback unit and a load output unit. A dual-safety interlocking structure combining software interlocking and contactor hardware interlocking is realized through a PLC, and two paths of power outputs cannot be switched on at the same time. The device has the functions of intelligent mode switching, real-time voltage monitoring, fusing and sudden stop dual protection, operation state feedback and practical training data storage, meets industrial-grade and safety-grade practical training requirements, is compact in structure and high in safety, supports closed-loop control and data tracing, and is suitable for modern electrician skill training and intelligent examination and identification.

The invention discloses a high-power modular radio frequency power amplifier capable of realizing wide-range power regulation. The high-power modular radio frequency power amplifier comprises a radio frequency load RL and m power amplification modules, the m power amplification modules are connected in parallel at a direct current side and are connected with an adjustable direct current bus voltage source; and the m power amplification modules are connected in parallel at the alternating current side and are superposed at the alternating current side. The output current of all the power amplification modules is transmitted to the radio frequency load RL; each power amplification module comprises a high-frequency switch power amplification unit, an LCL resonance network and an isolation transformer. According to the invention, through the configuration of the number of the power amplification modules and the adjustable cooperative control of the DC bus voltage source, the continuous adjustment of the output power is realized, meanwhile, the stable operation of each power amplification module under the resonance condition is ensured, the zero-voltage switching state is maintained, and the overall operation efficiency of the architecture and the adaptability of the radio frequency load are effectively improved.

The utility model discloses a power supply and a system used for nuclear fusion field anti-configuration. The power supply comprises a DC power supply, an inverter, a multi-output isolation transformer and N resonant branches. The direct-current power supply is electrically connected with the inverter; the inverter is used for converting the direct current into alternating current; the inverter is connected with the input end of the multi-output isolation transformer; and a plurality of output ends of the multi-output isolation transformer are respectively connected with one resonant branch. Structural improvement is carried out on the basis of a traditional field inversion configuration power supply technology, the charging function of capacitors of all branches of a coil is achieved through a transformer, all the branches are isolated from one another in the charging process, and mutual interference and influence are avoided; and meanwhile, the safety of other branches is not influenced when a single branch fails or is damaged in the working process.

The application discloses a novel lung lobe-shaped magnetic shielding partial discharge detection device and a detection method. The device comprises an isolation transformer, a bushing, a detection electrode and a partial discharge instrument. A single-phase power supply is connected with a reactor in parallel, and then connected with an input end of the isolation transformer. One end of an output end of the isolation transformer is connected with the bushing, and then connected with the detection electrode. The other end of the output end of the isolation transformer is grounded. A grounding end of a to-be-detected lung lobe-shaped magnetic shielding is grounded, and the grounding end of the to-be-detected lung lobe-shaped magnetic shielding is connected with the partial discharge instrument. The to-be-detected lung lobe-shaped magnetic shielding and the detection electrode are correspondingly arranged to form an equivalent capacitor and are coupled and connected. The application can be used to determine whether there is a defect in the lung lobe-shaped magnetic shielding by performing a partial discharge test on the lung lobe-shaped magnetic shielding before the lung lobe-shaped magnetic shielding is assembled into a transformer. The application has the characteristics of high test efficiency and low applied voltage, and greatly improves the first-time pass rate of the transformer product provided with the lung lobe-shaped magnetic shielding.

The utility model provides a control circuit of a capsule endoscope system, which comprises a protection unit and a working unit, two ends of the protection unit are respectively connected with a power supply and the working unit, and the protection unit comprises a fuse, a leakage protection switch, a reactor, a filter and an isolation transformer which are connected in series. The reactor is closer to the power supply than the isolation transformer. According to the control circuit of the capsule endoscope system, the safety of the control circuit can be improved.

In the DAB converter, the control circuit (13) controls in a manner including a first period in which the first DC portion (E1, Ca) is conducted with the primary winding (n1) of the isolation transformer (TR1), and a second period in which both ends of the primary winding (n1) of the isolation transformer (TR1) are short-circuited within the first bridge circuit (11), in the case of step-down transmission of electric power from the first DC portion (E1, Ca) to the second DC portion (E2, Cb). The control circuit (13) generates: a first mode in which the fourth switching element (Q4) is off, and the first period is switched to the second period; a second mode in which the second switching element (Q2) is off, and the first period is switched to the second period; a third mode in which the first switching element (Q1) is off, and the first period is switched to the second period; and a fourth mode in which the third switching element (Q3) is off, and the first period is switched to the second period.

The invention discloses a large-capacity energy storage converter based on a DAB-ANPC cascade architecture, which comprises a pre-stage DC-DC converter and a post-stage DC-AC inverter which are cascaded, the pre-stage DC-DC converter adopts a dual active bridge (DAB) circuit and comprises a primary and secondary full bridge, a high-frequency isolation transformer, a series inductor and a blocking capacitor, and electrical isolation and wide voltage input are realized; the back-stage DC-AC inverter is a three-phase three-level active neutral point clamp (ANPC) topology, each phase of bridge arm comprises six full-control switches, loss is balanced through the clamp switches, and the output end of the back-stage DC-AC inverter is connected with the LCL filter. According to the invention, DAB power transmission is controlled and adjusted through single phase shift, and an ANPC switch tube conduction time sequence is dynamically allocated by adopting stacked carrier SPWM modulation, so that the problems of electrical isolation and wide voltage can be solved, and a new energy fluctuation scene is compatible; the device loss is balanced, local overheating is avoided, and the system efficiency and reliability are improved; soft switching and LCL filtering are cooperated, so that the switching loss and harmonic interference are reduced, and the cost is reduced; bidirectional energy flow is supported, and the charging and discharging requirements of an energy storage power station are met.

The invention provides a heating and heat preservation system and a temperature control method for a suspension type monorail turnout in a cold region, and the system is provided with a plurality of temperature detection devices, a temperature controller, an operation interface, an isolation transformer, a heating control box and a heating device, the temperature controller is interactively and electrically connected with the operation interface and the heating control box; the input end of the heating control box is connected with the isolation transformer, and the output end is connected with the heating device. The temperature control method comprises two processes: an active special processing process and an automatic temperature control process. The mode of multiple temperature control points, multiple temperature sections and multiple control processes is adopted, the usability, reliability and safety of the suspension type monorail turnout system in the cold environment are improved, and the method is suitable for popularization.

A flexible loop-closing device and its active power control method are disclosed. The device includes a power electronic transformer and distribution networks connected to both sides. Each phase of the power electronic transformer includes several power modules symmetrically arranged on both sides. Each power module includes an H-bridge section composed of power electronic switching devices T1-T4 and a DAB section composed of power electronic switching devices T5-T8. The power modules on both sides are connected through a resonant inductor Lr and an isolation transformer T. The H-bridge sections of the power modules on the same side are connected in series to the high-voltage AC bus of the distribution network on the same side. The active power control method is as follows: the AC side of the loop-closing device is controlled by a cascaded H-bridge, and the DC side is controlled by a DAB. When there is no active power flow control requirement, the DAB section does not need to work, and the DC bus voltage of the power modules on both sides is controlled by their respective cascaded H-bridges. This method can simplify the operation complexity of the loop-closing device to the greatest extent, ensure the stable operation of the loop itself and the reliability of the system power supply, and greatly reduce the system losses when there is no active power flow control requirement. The active power control strategy proposed in this invention can avoid frequent switching of the cascaded H-bridge control mode, ensure the stable operation of the flexible loop-closing system, and improve the dynamic response speed.

This utility model relates to an electric shock protection safety isolation distribution box, belonging to the technical field of distribution boxes. The electric shock protection safety isolation distribution box includes a distribution box, an air switch installed on the inner wall of the distribution box, an isolation transformer installed on the inner wall of the distribution box, a fixing component installed at the bottom of the isolation transformer, and a branch sealing component installed on the inner wall of the distribution box. This utility model allows adjustment of the distance between two L-shaped brackets by unscrewing a screw on one side and pulling a slider. The slider's sliding distance is adjusted according to the bottom hole position of the replacement isolation transformer. The screws are then tightened to fix the L-shaped brackets to the inner wall of the distribution box. Finally, the new isolation transformer is installed in the corresponding square slot. This improves versatility and flexibility, eliminating the need for custom-made enclosures for different transformers, reducing equipment replacement or upgrade costs, adapting to different power and model requirements, and broadening the applicable scenarios.

The application discloses a kind of transformer intelligent enclosed neutral point protection devices, including maintenance switch, lightning arrester, capacitive voltage divider, filter module, isolation transformer, charge-discharge module, voltage detection module, gap discharge unit, digital control unit;Filter module is used to filter the voltage signal of capacitive voltage divider after voltage division flows into isolation transformer, removes high-frequency signal, retains power frequency or its multiple frequency signal, realizes the distinction of transient overvoltage signal and steady overvoltage signal;Voltage detection module is used to detect the voltage amplitude of four capacitors in charge-discharge module, duration, and real-time transmission detection data to digital control unit, and digital control unit real-time uploads detection data to main control background, control pulse trigger controllable switch opens or closes, control discharge of enclosed discharge gap.The application realizes the accurate identification of transformer neutral point overvoltage type, solves the problem of high misoperation rate of existing device, damage transformer.

The present disclosure describes an isolated communication device and a multi-level encoding method therefor. The isolated communication device includes a transceiver (10) and an isolation circuit (20). The isolation circuit (20) includes an isolation transformer (T1) having a driver-side winding and a line-side winding, a first serial resistor (R11) that is coupled with a first end of the driver-side winding, and a second serial resistor (R12) that is coupled with a second end of the driver-side winding. The transceiver (10) transmits a differential signal through the first serial resistor (R11) and the second serial resistor (R12), and receives the differential signal, bypassing the first serial resistor (R11) and the second serial resistor (R12). The isolated communication device reduces power consumption by arranging serial resistors at the driver side of the isolation transformer, and improve impedance matching and strengthen bulk current injection (BCI) immunity by arranging serial resistors at both sides of the isolation transformer.

The invention belongs to the technical field of combustion equipment, and relates to a plasma ignition system and a using method thereof. The system comprises a plasma generator, a combustor, a power supply system, a carrier working medium system and a cooling water system, an anode and a cathode of the plasma generator are coaxially arranged to form an electric arc cavity and a surrounding cooling water cavity, and the anode is provided with a compressed air inlet and a plasma jet outlet; the plasma combustor is sequentially and coaxially sleeved with a first-stage center cylinder, a second-stage combustion cylinder and an outer wall cylinder from inside to outside, the first-stage center cylinder communicates with the jet flow outlet, and the outer wall cylinder is provided with a pulverized coal inlet; the power supply system supplies power to the generator through the isolation transformer and the rectifier cabinet. The carrier working medium system supplies air to the compressed air inlet; the cooling water system enables demineralized water to circulate in the cooling water cavity. Efficient and stable ignition and low-nitrogen combustion of pulverized coal are achieved, the ignition reliability is remarkably improved, the system service life is remarkably prolonged, and the operation automation level is remarkably improved.

The application discloses a kind of for inhibiting loop current's transformer area flexible interconnection system, wherein, first flexible interconnection device and second flexible interconnection device include DC common mode inductance, parallel four-phase bridge arm, first controller and second controller, two DC common mode inductances are connected to the positive and negative poles of four-phase bridge arm respectively and are respectively as positive and negative DC side port, the midpoint of four-phase bridge arm is respectively as four-phase AC side port, the control pole of the first three-phase bridge arm in four-phase bridge arm is respectively connected to first controller, the control pole of the last phase bridge arm is respectively connected to second controller;First, second flexible interconnection device is connected by positive and negative DC side port, and first, second flexible interconnection device is connected by four-phase AC side port four phase lines of the distribution transformer of first, second distribution transformer area. The application can realize transformer area flexible interconnection without isolation, and solve the technical problem that ground loop current is too large when isolation transformer is cancelled.

The utility model relates to the technical field of axle counting isolation transformers, and discloses an axle counting isolation transformer modularization rapid installation support which comprises a plurality of sets of long module strips, high module strips and wide module strips, and the ends of the long module strips, the high module strips and the wide module strips are all provided with step assembling grooves. The long module strips, the high module strips and the wide module strips are sequentially assembled to form a frame. The multiple groups of long module strips, high module strips and wide module strips can be flexibly assembled according to actual requirements to form mounting brackets with different sizes and structures, so that the mounting process is greatly simplified, and the mounting time is shortened. Meanwhile, due to the adoption of the modular design, the transformer is more convenient to adjust or replace, an operator only needs to disassemble and reassemble the corresponding modules, and does not need to change the whole mounting bracket on a large scale, so that the working efficiency is improved, and the maintenance cost is also reduced.

The invention discloses a trapezoidal wave control method of a double-active-bridge direct-current transformer and related equipment, and relates to the technical field of direct-current transformers. In the double-active-bridge direct-current transformer, the first side of a first active bridge is electrically connected with a first direct-current port, the first end of the second side of the first active bridge is electrically connected with the first end of an auxiliary inductor, and the second end of the auxiliary inductor is electrically connected with the first end of a primary winding of an isolation transformer. The second side of the first active bridge is electrically connected with the second end of the primary winding of the isolation transformer; a secondary winding of the isolation transformer is electrically connected with a first side of a second active bridge, and a second side of the second active bridge is electrically connected with a second direct current port; the method comprises the following steps: controlling an inner phase shift angle of a first active bridge to be a first main phase shift angle, and controlling an inner phase shift angle of a second active bridge to be a second main phase shift angle; the difference value between the second main phase shift angle and the first main phase shift angle is a preset auxiliary phase shift angle. According to the embodiment of the invention, the operation reliability and efficiency of the double-active-bridge direct-current transformer can be improved.

The application relates to a high-voltage power-taking capacitor protection and harmonic suppression system and a circuit thereof, and belongs to the field of power distribution network intelligent control switch power taking. The circuit is arranged between an isolation transformer and a feeder terminal unit (FTU), and comprises an input protection circuit for suppressing input surge overvoltage and fast pulse group, a harmonic filter circuit for filtering out harmonics, a signal acquisition and conditioning circuit for converting an alternating current signal into a direct current voltage signal, and a control protection circuit for comparing the direct current voltage signal with a preset reference voltage. The system further comprises a high-voltage capacitor voltage divider, an isolation transformer and the feeder terminal unit (FTU). The application effectively solves the problem that harmonic interference, surge impact and overvoltage risk coexist in the high-voltage power-taking system, greatly improves the safety and reliability of the operation of the rear-end FTU equipment under the premise of ensuring the accuracy of voltage signal measurement and power supply continuity.

This application relates to the field of transformer technology, specifically to a power electronic transformer with an embedded liquid-cooling channel in the windings. The transformer includes a power conversion module, a high-frequency isolation transformer, and a control module. The input terminal of the power conversion module is used to connect to an input power supply. The high-frequency isolation transformer includes a magnetic core, a primary winding, and a secondary winding. The control module controls the power conversion process of the power conversion module. Specifically, the primary winding and / or the secondary winding includes multiple conductive winding plates. The high-frequency isolation transformer also includes a liquid-cooling plate and an embedded liquid-cooling channel disposed within the liquid-cooling plate. The liquid-cooling plate and the multiple conductive winding plates are stacked, and the embedded liquid-cooling channel contains coolant. This invention enhances the internal heat dissipation capacity of the high-frequency isolation transformer through embedded liquid cooling, better meeting the engineering requirements of high power density, miniaturization, and continuous operation.

The utility model discloses an isolation type voltage sag active protection device, which is arranged between a three-phase full-bridge rectification circuit and a frequency converter direct current bus, and comprises a full-bridge LLC resonant converter, a DSP digital control circuit and an isolation unit, and direct current output by the three-phase full-bridge rectification circuit is converted into stable direct current through the full-bridge LLC resonant converter. The isolation unit is connected with a frequency converter DC bus; wherein the DSP digital control circuit controls on and off of a switching tube in the full-bridge LLC resonant converter by generating a PWM signal. According to the isolation type voltage sag active protection device of the utility model, efficient and stable electric energy conversion is realized through the full-bridge LLC resonant converter and the DSP digital control circuit; and furthermore, through the isolation unit and the high-frequency isolation transformer, effective isolation between the power supply and the load is realized, and the system safety is improved.

The utility model belongs to the technical field of shore power, and particularly relates to a wide, efficient and multipurpose ship shore-based power supply system. Comprising a high-capacity shore-based variable-frequency power supply subsystem and a multi-power-system interface low-voltage shore power supply subsystem, the high-capacity shore-based variable-frequency power supply subsystem comprises a high-voltage power supply incoming line, a step-down transformer, a variable-frequency and variable-voltage device and an isolation transformer which are connected in sequence; the multi-power-system interface low-voltage shore power supply subsystem comprises a low-capacity shore power output system, an output automatic switching interlocking protection system and multi-interface low-voltage shore power which are connected in sequence; according to the power supply system designed in the scheme, through deepening design processing on an existing shore power system, multiple switching of shore power interfaces is achieved, the application range is wide, energy efficiency consumption is low, the equipment utilization rate is greatly improved, the actual problem of connection of shore power at a wharf is solved, and a good solution is provided for popularization of shore power use full coverage.