阅读说明：本技术 磁悬浮列车的供电系统、方法、存储介质和处理器 (Power supply system, method, storage medium and processor for magnetic suspension train ) 是由 曹智宇 贾晶艳 于 2021-08-05 设计创作，主要内容包括：本申请公开了一种磁悬浮列车的供电系统、方法、存储介质和处理器。该系统包括：高压电网；中压直流电网；地面变流站；其中,所述高压电网通过变压器和变流器与所述中压直流电网联接；所述中压直流电网与所述地面变流站中的三端口模块化中压变流装置MMC变流器的第一端联接；直流母线与所述三端口MMC变流器的第二端联接；所述三端口MMC变流器的第三端与中压交流输出端联接,输出可变频变压的三相交流电,以对磁悬浮列车的长定子供电。通过本申请,解决了相关技术中磁悬浮列车供电系统的供电效果不佳的问题。(The application discloses a power supply system, a power supply method, a storage medium and a processor of a magnetic suspension train. The system comprises: a high voltage power grid; a medium voltage direct current grid; a ground converter station; wherein the high voltage grid is coupled to the medium voltage direct current grid through a transformer and a converter; the medium-voltage direct-current power grid is connected with a first end of a three-port modular medium-voltage converter MMC converter in the ground converter station; the direct current bus is connected with the second end of the three-port MMC converter; and the third end of the three-port MMC converter is connected with the medium-voltage alternating-current output end to output variable-frequency and variable-voltage three-phase alternating current so as to supply power to a long stator of the magnetic suspension train. Through the application, the problem that the power supply effect of the power supply system of the magnetic suspension train in the related technology is poor is solved.)

1. A power supply system for a magnetic levitation vehicle, comprising:

a high voltage power grid;

a medium voltage direct current grid;

a ground converter station;

wherein the high voltage grid is coupled to the medium voltage direct current grid through a transformer and a converter;

the medium-voltage direct-current power grid is connected with a first end of a three-port modular medium-voltage converter MMC converter in the ground converter station;

the direct current bus is connected with the second end of the three-port MMC converter;

and the third end of the three-port MMC converter is connected with the medium-voltage alternating-current output end to output variable-frequency and variable-voltage three-phase alternating current so as to supply power to a long stator of the magnetic suspension train.

2. The system of claim 1, wherein the three-port MMC converter comprises a plurality of three-port MMC modules, and wherein the DC terminal of each three-port MMC module is provided with a DC-DC converter electrically isolated from the DC terminal of the DC bus and each three-port MMC module, wherein the DC-DC converter comprises: a DC-AC inverter, a transformer and a rectifier.

3. The system of claim 2, further comprising:

the photovoltaic power station is connected to the direct-current bus through the boost chopper of the DC-DC converter;

the wind power station is connected with the direct current bus in an AC-DC controllable boosting rectification mode, or is connected with the direct current bus in an AC-DC uncontrollable rectification and DC-DC converter boosting chopping mode;

and the battery energy storage unit is connected to the direct-current bus through the boosting chopper of the DC-DC converter.

4. The system of claim 2, wherein the DC-DC converter comprises: the three-port MMC module comprises a DC-AC inverter, a transformer and a rectifier, wherein the transformer comprises a plurality of secondary windings, and each secondary winding is respectively connected with the direct current end of one three-port MMC module.

5. The system according to claim 1, wherein the high voltage power grid is a high voltage alternating current power grid or a high voltage direct current power grid, wherein if the high voltage power grid is a high voltage alternating current power grid, a step-down transformer and an AC-DC converter are used with a medium voltage direct current power grid; and if the high-voltage power grid is a high-voltage direct-current power grid, a DC-DC converter containing electric isolation is adopted to be connected into the medium-voltage direct-current power grid.

6. A method for supplying power to a maglev train, wherein the method for supplying power is applied to a system for supplying power to a maglev train as claimed in claim 3, wherein the three-port MMC converter comprises: low pressure direct current input, middling pressure direct current input or output, middling pressure alternating current input or output include:

judging whether renewable energy sources and the battery energy storage unit are in a shutdown state, wherein the renewable energy sources comprise: a photovoltaic power plant and a wind power plant;

if the renewable energy source and the battery energy storage unit are not in a shutdown state, determining a power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit;

and adopting the power supply strategy to supply power to the long stator of the magnetic suspension train.

7. The method of claim 6, wherein determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises:

if the output power of the renewable energy source and the output power of the battery energy storage unit are the same as the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, and supplying power to the long stator of the magnetic suspension train through the output of the ground converter station.

8. The method of claim 6, wherein determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises:

if the output power of the renewable energy source and the output power of the battery energy storage unit are smaller than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the renewable energy source and the output power of the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously acquiring electric energy from a medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station to complement the energy demand lacking in the maglev train, wherein the electric energy acquired from the medium-voltage direct current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct current power grid.

9. The method of claim 6, wherein determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises:

if the output power of the renewable energy source and the output power of the battery energy storage unit are larger than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously feeding back electric energy to the medium-voltage direct current power grid through controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or feeding back the electric energy to the high-voltage power grid.

10. The method of claim 6, further comprising:

and if the renewable energy source and the battery energy storage unit are in a shutdown state, acquiring electric energy from a medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the maglev train, wherein the electric energy acquired from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

11. The method of claim 6, further comprising:

if the renewable energy source and the battery energy storage unit are not in a shutdown state and the maglev train is in an unoperated state, the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and electric energy is fed back to the medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

12. The method of claim 6, further comprising:

if the maglev train is in a regenerative braking working condition, transmitting regenerative braking power output by the maglev train to the ground converter station, transmitting the output of the ground converter station to a medium-voltage direct-current power grid, simultaneously transmitting the renewable energy and the output power of the battery energy storage unit to the ground converter station through the direct-current bus, and feeding back electric energy to the medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct-current power grid or feeding back the electric energy to the high-voltage power grid.

13. A method for supplying power to a magnetic levitation vehicle, which is applied to a power supply system for a magnetic levitation vehicle as recited in claim 1, comprising:

the method comprises the steps that a two-port MMC converter of the ground converter station is controlled to obtain electric energy from a medium-voltage direct-current power grid so as to supply power to a long stator of the maglev train, wherein the electric energy obtained from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

14. A computer-readable storage medium, characterized in that the storage medium comprises a stored program, wherein the program performs the method of any one of claims 6 to 13.

15. A processor, configured to run a program, wherein the program when running performs the method of any one of claims 6 to 13.

Technical Field

The application relates to the technical field of train power supply, in particular to a power supply system, a power supply method, a storage medium and a processor of a magnetic suspension train.

Background

The current high-speed rail takes a wheel-rail technology as a main stream, and the running speed is within 400 km/h. As the operating speed increases, the tractive power required by the locomotive also increases. Beyond 400km/h, the wheel-track technology is often difficult to implement. For example, a high-speed train with a total length of 300m needs up to 20MW of traction power under the operation condition of 500 km/h. On the one hand, it is technically difficult to implement, for example: excessive axle weight (over 10 tons), too high noise, difficult control of mechanical shock, etc.; on the other hand, the method also has poor economical efficiency, such as serious abrasion of wearing parts such as rails, wheel sets and the like.

Magnetic levitation technology is a viable technology to solve the above problems. At present, the magnetic levitation technology mainly comprises: short stator technology and long stator technology. The short stator technology is adopted for magnetic suspension trains, and the asynchronous linear motor technology is usually adopted. The stator coil of the linear motor and the corresponding converter are installed on a train, and the rotor adopts a simple aluminum bar and is installed on a roadbed track. Compared with the long stator technology, the technology has low cost. However, since a high-power traction converter system needs to be installed on the train, the weight of the train is greatly increased. Therefore, the technology is only suitable for low-power medium-low speed maglev trains. High-speed magnetic levitation generally employs a long stator technology based on a linear permanent magnet synchronous motor. Compared with the short stator technology, the long stator technology needs to lay set sub-coils on the roadbed track, so the manufacturing cost is higher. However, since the stator coil is fed by a converter (including a transformer, a switching device, and the like) installed on the ground, the train weight is low and the speed can be increased.

In the prior art, a long stator (ground) power supply system of a high-speed magnetic suspension train is shown in fig. 1. As with conventional power systems, high voltage ac transmission networks supply power to medium voltage ac distribution networks through high voltage transformers; the medium-voltage alternating-current power grid supplies power to the long stator coil through the ground converter station. The ground converter station comprises a medium-voltage AC-DC-AC converter (comprising a rectifier, an intermediate DC link and an inverter) and a switch device, and outputs voltage with adjustable frequency (VVVF) to a line cable. The line cable is connected or disconnected with the corresponding long stator coil through a switching device, so that the variable-frequency variable-voltage control of the corresponding long stator linear motor is realized. The length of the long stator coils is typically 500 … 1500m and the distance between the ground converter stations is typically 30 … 50 km. It should be noted that fig. 1 is simplified to some extent. Each ground converter station usually contains 2-3 medium voltage converters for supplying power to the long stators on the left and right sides.

Under traction conditions, the energy flow direction is as shown in fig. 1, and is: high voltage AC network → medium voltage AC network → ground converter station → maglev train.

As shown in fig. 2, the electrical structure diagram of the medium voltage converter in fig. 2 specifically includes the following identifiers: 1. an input transformer; 2. a rectifier; 3. an intermediate direct current link; 4. a chopper resistor; 5. (three-level) inverters; 6. and an output transformer. Due to the high power of the medium voltage converter, for example, 400km/h requires a converter power of about 12 MVA; the converter power required for 500km/h is about 20MVA, and in order to reduce the current and cross-sectional area of the long stator coil and thus reduce the stator coil cost, the converter output voltage should be as high as possible. Therefore, inverters typically employ a multi-level (e.g., three-level) topology. Meanwhile, the primary side of the output transformer adopts a three-tap structure. In a low-speed area (requiring lower voltage and larger current), the alternating current outputs of the two inverters are connected in parallel through the primary side of the transformer, and the output of a middle tap of the transformer supplies power to a long stator coil (the transformer only plays the role of a shunt reactor); in the high-speed area, the alternating current outputs of the two inverters are connected in series through the primary side of the transformer, and the secondary side of the transformer supplies power to the long stator coil.

Aiming at the problem of poor power supply effect of a power supply system of a magnetic suspension train in the related technology, an effective solution is not provided at present.

Disclosure of Invention

The present application mainly aims to provide a power supply system, a power supply method, a storage medium, and a processor for a maglev train, so as to solve the problem of poor power supply effect of the maglev train power supply system in the related art.

In order to achieve the object defined above, according to one aspect of the application, a power supply system for a magnetic levitation vehicle is provided. The system comprises: a high voltage power grid; a medium voltage direct current grid; a ground converter station; wherein the high voltage grid is coupled to the medium voltage direct current grid through a transformer and a converter; the medium-voltage direct-current power grid is connected with a first end of a three-port modular medium-voltage converter MMC converter in the ground converter station; the direct current bus is connected with the second end of the three-port MMC converter; and the third end of the three-port MMC converter is connected with the medium-voltage alternating-current output end to output variable-frequency and variable-voltage three-phase alternating current so as to supply power to a long stator of the magnetic suspension train.

Further, including a plurality of three port MMC modules in the three port MMC converter, the direct current end of every three port MMC module is provided with the DC-DC converter of a function galvanic isolation, the DC-DC converter is used for hookup the direct current end of direct current bus and every three port MMC module, wherein, the DC-DC converter includes: a DC-AC inverter, a transformer and a rectifier.

Further, the system further comprises: the photovoltaic power station is connected to the direct-current bus through the boost chopper of the DC-DC converter; the wind power station is connected with the direct current bus in an AC-DC controllable boosting rectification mode, or is connected with the direct current bus in an AC-DC uncontrollable rectification and DC-DC converter boosting chopping mode; and the battery energy storage unit is connected to the direct-current bus through the boosting chopper of the DC-DC converter.

Further, the DC-DC converter includes: the three-port MMC module comprises a DC-AC inverter, a transformer and a rectifier, wherein the transformer comprises a plurality of secondary windings, and each secondary winding is respectively connected with the direct current end of one three-port MMC module.

Further, the high-voltage power grid is a high-voltage alternating current power grid or a high-voltage direct current power grid, wherein if the high-voltage power grid is the high-voltage alternating current power grid, a step-down transformer and an AC-DC converter are connected with the medium-voltage direct current power grid; and if the high-voltage power grid is a high-voltage direct-current power grid, a DC-DC converter containing electrical isolation is adopted to be connected into the medium-voltage direct-current power grid.

In order to achieve the above object, according to an aspect of the present application, there is provided a power supply system for a maglev train, wherein the power supply method is applied to the maglev train, and the three-port MMC converter includes: low pressure direct current input, middling pressure direct current input or output, middling pressure alternating current input or output include: judging whether renewable energy sources and the battery energy storage unit are in a shutdown state, wherein the renewable energy sources comprise: a photovoltaic power plant and a wind power plant; if the renewable energy source and the battery energy storage unit are not in a shutdown state, determining a power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit; and adopting the power supply strategy to supply power to the long stator of the magnetic suspension train.

Further, determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are the same as the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, and supplying power to the long stator of the magnetic suspension train through the output of the ground converter station.

Further, determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are smaller than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the renewable energy source and the output power of the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously acquiring electric energy from a medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station to complement the energy demand lacking in the maglev train, wherein the electric energy acquired from the medium-voltage direct current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct current power grid.

Further, determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are larger than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously feeding back electric energy to the medium-voltage direct current power grid through controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or feeding back the electric energy to the high-voltage power grid.

Further, the method further comprises: and if the renewable energy source and the battery energy storage unit are in a shutdown state, acquiring electric energy from a medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the maglev train, wherein the electric energy acquired from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

Further, the method further comprises: if the renewable energy source and the battery energy storage unit are not in a shutdown state and the maglev train is in an unoperated state, the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and electric energy is fed back to the medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

Further, the method further comprises: if the maglev train is in a regenerative braking working condition, transmitting regenerative braking power output by the maglev train to the ground converter station, transmitting the output of the ground converter station to a medium-voltage direct-current power grid, simultaneously transmitting the renewable energy and the output power of the battery energy storage unit to the ground converter station through the direct-current bus, and feeding back electric energy to the medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct-current power grid or feeding back the electric energy to the high-voltage power grid.

In order to achieve the above object, according to one aspect of the present application, there is provided a power supply method for a magnetic levitation vehicle, the power supply method being applied to the power supply system for a magnetic levitation vehicle, including: the method comprises the steps that a two-port MMC converter of the ground converter station is controlled to obtain electric energy from a medium-voltage direct-current power grid so as to supply power to a long stator of the maglev train, wherein the electric energy obtained from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

In order to achieve the above object, according to one aspect of the present application, there is provided a storage medium including a stored program, wherein the program performs the method of any one of the above.

To achieve the above object, according to one aspect of the present application, there is provided a processor for executing a program, wherein the program executes to perform the method of any one of the above.

The power supply system for a magnetic levitation train of the present application comprises: a high voltage power grid; a medium voltage direct current grid; a ground converter station; wherein the high voltage grid is coupled to the medium voltage direct current grid through a transformer and a converter; the medium-voltage direct-current power grid is connected with a first end of a three-port modular medium-voltage converter MMC converter in the ground converter station; the direct current bus is connected with the second end of the three-port MMC converter; the third end of three port MMC converter links with middling pressure alternating current output end, but the three-phase alternating current of output variable frequency vary voltage to supply power to the long stator of maglev train, solved the not good problem of power supply effect of maglev train power supply system among the correlation technique, reached and promoted the power supply effect of maglev train power supply system, and through multiplexing and effectual control strategy to three port MMC converters of ground converter station, effectively reduce renewable energy's access and incorporated into the power networks the cost.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application. In the drawings:

FIG. 1 is a schematic diagram of a high speed maglev train long stator power supply system in the prior art;

FIG. 2 is a prior art circuit block diagram of a medium voltage converter;

FIG. 3 is a schematic diagram of a power supply system provided in accordance with an embodiment of the present application that does not include renewable energy access to a magnetic levitation vehicle;

fig. 4 is a block diagram of a two-port MMC converter circuit of a ground converter station that does not include renewable energy access provided in accordance with an embodiment of the present application;

fig. 5 is a schematic diagram of a long stator power supply system of a magnetic levitation train with renewable energy access provided in accordance with an embodiment of the present application;

fig. 6 is a circuit structure diagram of a novel MMC converter circuit including three ports for a ground converter station provided in an embodiment of the present application;

FIG. 7 is a flow chart of a method for powering a magnetic levitation train provided in accordance with an embodiment of the present application;

FIG. 8 is a first schematic diagram illustrating the flow of electrical energy in a method for supplying power to a magnetic levitation vehicle according to an embodiment of the present application;

FIG. 9 is a schematic diagram II of the flow of electric energy in the method for supplying power to a magnetic levitation train according to the embodiment of the present application;

fig. 10 is a schematic diagram three illustrating the flow of electric energy in the method for supplying power to a magnetic levitation train according to the embodiment of the present application;

fig. 11 is a schematic diagram of the flow direction of electric energy in the power supply method of a magnetic levitation train provided according to the embodiment of the present application;

fig. 12 is a schematic flow diagram of electric energy in a method for supplying power to a magnetic levitation train according to an embodiment of the present application;

fig. 13 is a sixth schematic flow diagram of electric energy in a method for supplying power to a magnetic levitation vehicle according to an embodiment of the present application;

fig. 14 is a schematic structural diagram of an alternative three-port MMC converter circuit provided in an embodiment of the present application.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

According to an embodiment of the present application, a power supply system for a magnetic levitation train is provided. As shown in fig. 3, the system includes: a high voltage power grid; a medium voltage direct current grid; a ground converter station; the high-voltage power grid is connected with the medium-voltage direct-current power grid through a transformer and a converter; the medium-voltage direct-current power grid is connected with a first end of a modular medium-voltage converter device two-port MMC converter in the ground converter station; the second end of the two-port MMC converter is connected with the medium-voltage alternating-current output end to output variable-frequency and variable-voltage three-phase alternating current so as to supply power to a long stator of the magnetic suspension train.

The high-voltage power grid can be a high-voltage alternating current power grid or a high-voltage direct current power grid, wherein if the high-voltage power grid is the high-voltage alternating current power grid, a step-down transformer and an AC-DC converter are adopted to be connected with the first end of the two-port MMC converter; and if the high-voltage power grid is a high-voltage direct-current power grid, connecting a DC-DC converter containing electric isolation to a first end of a two-port MMC converter. In the embodiment of the present application, a medium-voltage direct-current power grid is adopted to replace a medium-voltage alternating-current power grid in the related art, which can significantly reduce voltage transmission loss. In the embodiment of the present application, an MMC converter structure (as shown in fig. 4, a plurality of sub-modules are connected in series) is further adopted, so that the voltage limitation of the device can be eliminated, and the output voltage can be much higher than that of the prior art. Therefore, under the condition of the same converter output power, the output voltage is obviously improved, the output current is reduced, the sectional areas of a line cable and a stator coil are reduced, and the cost is reduced. Or, under the condition that the output current is the same, the converter output power of the ground converter station is obviously improved by improving the output voltage, and the distance between the ground converter stations is increased, so that the cost is also reduced. Meanwhile, because the equivalent switch of the MMC structure converter is far higher than the multi-level inverter in the prior art, the output voltage and current harmonic waves are obviously reduced, the power supply quality is greatly improved, and the harmonic loss is reduced.

Through above-mentioned scheme, the not good problem of maglev train power supply system's power supply effect among the correlation technique has been solved, and middling pressure direct current electric wire netting reduces voltage transmission loss, and further, adopts the MMC converter, improves output voltage, has reduced the harmonic of output voltage and electric current, has reduced the power supply cost to maglev train power supply system's power supply effect has been promoted.

Optionally, as shown in fig. 5, a three-port MMC converter is adopted in the power supply system of the maglev train provided in the embodiment of the present application, so that multiplexing of the converter and grid-connected access of renewable energy are realized. The three-port MMC converter comprises a plurality of three-port MMC modules, the direct current end of each three-port MMC module is provided with a DC-DC converter which is electrically isolated from a function, the DC-DC converter is used for connecting a direct current bus and the direct current end of each three-port MMC module, and the DC-DC converter comprises: a DC-AC inverter, a transformer and a rectifier.

The DC-DC converter in the above scheme may further include: the three-port MMC module comprises a DC-AC inverter, a transformer and a rectifier, wherein the transformer comprises a plurality of secondary windings, and each secondary winding is respectively connected with the direct current end of one three-port MMC module.

Optionally, in the power supply system for a magnetic levitation train provided in the embodiment of the present application, the system further includes: the photovoltaic power station is connected to the direct current bus through the boosting chopper of the DC-DC converter; the wind power station is connected with the direct current bus in an AC-DC controllable boosting rectification mode, or the wind power station is connected with the direct current bus in an AC-DC uncontrollable rectification and DC-DC converter boosting chopping mode; and the battery energy storage unit is connected to the direct-current bus through the boosting chopper of the DC-DC converter.

A schematic diagram of a maglev train long stator power supply system with renewable energy access is shown in fig. 5, a structural schematic diagram of a novel MMC converter circuit with three ports is shown in fig. 6, and a photovoltaic power station can be connected with a direct current bus through DC-DC boost chopper to access a three-port MMC converter in the power supply system. The wind power station can use AC-DC rectification and DC-DC boosting chopping, and is connected with a direct current bus to be connected into a three-port MMC converter in a power supply system. Or, the wind power station can also adopt a boosting AC-DC rectification mode and is connected with a direct current bus to be connected into a three-port MMC converter in a power supply system. Meanwhile, a battery energy storage unit can be added and is connected into a direct current bus through DC-DC boost chopper to be connected into a three-port MMC converter in a power supply system, so that the fluctuation of the power supply system is reduced, and the stability of the power supply system is improved.

According to another aspect of the present application, there is also provided a power supply method applied to the power supply system of a magnetic levitation train, the three-port MMC converter including: as shown in fig. 7, the power supply method includes the following steps:

step S701, judging whether the renewable energy source and the battery energy storage unit are in a shutdown state or not, wherein the renewable energy source comprises: photovoltaic power generation station and wind power generation station.

Step S702, if the renewable energy source and the battery energy storage unit are not in the shutdown state, determining a power supply strategy based on the output power of the renewable energy source and the battery energy storage unit.

And step S703, adopting a power supply strategy to supply power to the long stator of the magnetic suspension train.

Through the steps S701-S703, the power supply strategy for supplying power to the magnetic suspension train is determined based on the running states of the renewable energy sources and the battery energy storage unit, so that the power supply effect of the magnetic suspension train is ensured, and the access of the renewable energy sources and the reuse of a magnetic suspension power supply system are realized.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, determining the power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit includes: if the output power of the renewable energy source and the battery energy storage unit is the same as the required energy of the magnetic suspension train, determining that the power supply strategy is as follows: the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and the power is supplied to the long stator of the magnetic suspension train through the output of the ground converter station.

In the above solution, if the output power of the renewable energy source and the energy storage unit connected to the system completely coincides with the demand of the load (magnetic levitation train) (i.e. the output power of the renewable energy source and the battery energy storage unit is the same as the demand energy of the magnetic levitation train), the flow direction of the control power is: renewable energy → dc bus → ground converter → load, to power the long stator of the maglev train, as shown in fig. 8.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, determining the power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit includes: if the output power of the renewable energy source and the battery energy storage unit is less than the required energy of the magnetic suspension train, determining that the power supply strategy is as follows: the method comprises the steps that the output power of renewable energy sources and the output power of a battery energy storage unit are transmitted to a ground converter station through a direct current bus, the output of the ground converter station is used for supplying power to a long stator of the magnetic suspension train, meanwhile, electric energy is obtained from a medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station, and the energy demand of the magnetic suspension train which is lacked is complemented, wherein the electric energy obtained from the medium-voltage direct current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct current power grid.

In the above solution, if the output power of the renewable energy and energy storage unit connected to the system is lower than the load power (i.e. the required energy of the maglev train), the flow direction of the control electric energy is: renewable energy → dc bus → ground converter station, with insufficient power from: high voltage ac or dc grid → medium voltage dc grid → ground converter station, and finally ground converter station → load, to supply power to the long stator of the maglev train, as shown in fig. 9.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, determining the power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit includes: if the output power of the renewable energy source and the battery energy storage unit is greater than the required energy of the magnetic suspension train, determining that the power supply strategy is as follows: the method comprises the steps that the output power of renewable energy sources and the output power of a battery energy storage unit are transmitted to a ground converter station through a direct current bus, the output of the ground converter station is used for supplying power to a long stator of a magnetic suspension train, meanwhile, electric energy is fed back to a medium-voltage direct current power grid through controlling a three-port MMC converter of the ground converter station, and the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

In the above scheme, if the output power of the renewable energy and energy storage unit accessing the system is higher than the load power, the flow of the electric energy is controlled to be: renewable energy → direct current bus → ground converter station to supply power for the long stator of maglev train, ground converter station both supplies power to the load simultaneously, also feeds back the electric energy to the medium voltage direct current electric wire netting simultaneously, promptly: ground converter station → load (maglev train), ground converter station → medium voltage dc network, as shown in fig. 10. It should be noted that the feedback electric energy may be used for other loads of the medium-voltage dc power grid or fed back to the high-voltage power grid.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, the method further includes: if the renewable energy source and the battery energy storage unit are in a shutdown state, electric energy is obtained from a medium-voltage direct-current power grid through controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the magnetic suspension train, wherein the electric energy obtained from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

In the above scheme, if the renewable energy and the battery energy storage unit connected to the power supply system are in a shutdown state (i.e., the output power is 0), the flow direction of the electric energy is controlled to be: high voltage ac/dc network → medium voltage dc network → ground converter station → load, to power the long stator of the maglev train, as shown in fig. 11.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, the method further includes: if the renewable energy source and the battery energy storage unit are not in a shutdown state and the maglev train is in an unoperated state, the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and electric energy is fed back to the medium-voltage direct current power grid by controlling the three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

In the above scheme, the maglev train is in a non-running state, that is, the load power is 0, and the renewable energy source directly supplies power to the medium-voltage direct-current power grid through the ground converter station, that is, the flow direction of the electric energy generated by the renewable energy source is controlled to be: renewable energy → dc bus → ground converter station → medium voltage dc grid as shown in fig. 12. It should be noted that the electric energy fed back to the medium-voltage dc power grid is used for other loads of the medium-voltage dc power grid or fed back to the high-voltage power grid.

Optionally, in the power supply method for a magnetic levitation train provided in the embodiment of the present application, the method further includes: if the maglev train is in a regenerative braking working condition, transmitting regenerative braking power output by the maglev train to a ground converter station, transmitting the output of the ground converter station to a medium-voltage direct-current power grid, simultaneously transmitting the output power of renewable energy and a battery energy storage unit to the ground converter station through a direct-current bus, and feeding back electric energy to the medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct-current power grid or fed back to the high-voltage power grid.

In the above scheme, when the maglev train is in the regenerative braking condition, the flow direction of the control electric energy is as follows: load (maglev train) → ground converter station → medium voltage direct current network. Meanwhile, the power of renewable energy also flows to a medium-voltage direct-current power grid through a ground converter station: renewable energy → direct current bus → ground converter station → medium voltage direct current grid. As shown in fig. 13. It should be noted that the feedback electric energy may be used for other loads of the medium-voltage dc power grid or fed back to the high-voltage power grid.

In addition, it should be noted that, the DC-DC converter in the ground converter station three-port MMC converter, which is electrically isolated, can also be bi-directional technically, so that the energy of regenerative braking of the maglev train or the energy from the medium-voltage direct-current power grid flows to the battery energy storage unit. In this mode, the battery energy storage unit may operate in the following manner: the direct current bus is directly connected with the renewable energy source to store and adjust the energy generated by the renewable energy source. In addition, the DC-DC converter electrically isolated from the function in the three-port MMC converter can be implemented by adopting different topologies, as shown in fig. 14, for example, a DC-AC inverter with higher power is used on the DC bus side and connected to the primary side of the (intermediate frequency) transformer; the (intermediate frequency) transformer comprises a plurality of secondary windings, each secondary winding being associated with a respective dc input of a module of the MMC. In fig. 14, an intermediate frequency transformer comprising two secondary windings is illustrated.

If no power supply system with new energy access exists, according to another aspect of the present application, a power supply method is further provided for applying to the power supply system of the magnetic levitation train, and the two-port MMC converter of the ground converter station is controlled to obtain electric energy from the medium-voltage dc power grid to supply power to the long stator of the magnetic levitation train, wherein the electric energy obtained from the medium-voltage dc power grid comes from the high-voltage power grid or other power generation devices connected to the medium-voltage dc power grid.

Under the condition of no new energy access, a DC-DC converter and a second port (a port connected with a direct current bus) which are electrically isolated in a three-port MMC module can be eliminated, so that a two-port MMC converter is formed.

In conclusion, the power supply system and the power supply method of the magnetic suspension train disclosed by the application solve the problem of the deficiency of the high-speed magnetic suspension train stator power supply technology based on the long stator technology, and improve the power supply effect of the magnetic suspension train based on the long stator technology.

The processor comprises a kernel, and the kernel calls the corresponding program unit from the memory. One or more than one kernel can be set, and the power supply effect of the power supply system of the magnetic suspension train is improved by adjusting the kernel parameters.

The memory may include volatile memory in a computer readable medium, Random Access Memory (RAM) and/or nonvolatile memory such as Read Only Memory (ROM) or flash memory (flash RAM), and the memory includes at least one memory chip.

An embodiment of the present invention provides a storage medium having a program stored thereon, which when executed by a processor implements the method of supplying power to a magnetic levitation train.

The embodiment of the invention provides a processor, which is used for running a program, wherein the program executes the power supply method of the magnetic suspension train during running.

The embodiment of the invention provides equipment, which comprises a processor, a memory and a program which is stored on the memory and can run on the processor, wherein the processor executes the program and realizes the following steps: judging whether renewable energy sources and the battery energy storage unit are in a shutdown state, wherein the renewable energy sources comprise: a photovoltaic power plant and a wind power plant; if the renewable energy source and the battery energy storage unit are not in a shutdown state, determining a power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit; and adopting the power supply strategy to supply power to the long stator of the magnetic suspension train.

The processor executes the program and further realizes the following steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are the same as the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, and supplying power to the long stator of the magnetic suspension train through the output of the ground converter station.

The processor executes the program and further realizes the following steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are smaller than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the renewable energy source and the output power of the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously acquiring electric energy from a medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station to complement the energy demand lacking in the maglev train, wherein the electric energy acquired from the medium-voltage direct current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct current power grid.

The processor executes the program and further realizes the following steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are larger than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously feeding back electric energy to the medium-voltage direct current power grid through controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or feeding back the electric energy to the high-voltage power grid.

The processor executes the program and further realizes the following steps: the method further comprises the following steps: and if the renewable energy source and the battery energy storage unit are in a shutdown state, acquiring electric energy from a medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the maglev train, wherein the electric energy acquired from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

The processor executes the program and further realizes the following steps: if the renewable energy source and the battery energy storage unit are not in a shutdown state and the maglev train is in an unoperated state, the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and electric energy is fed back to the medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

The processor executes the program and further realizes the following steps: if the maglev train is in a regenerative braking working condition, transmitting regenerative braking power output by the maglev train to the ground converter station, transmitting the output of the ground converter station to a medium-voltage direct-current power grid, simultaneously transmitting the renewable energy and the output power of the battery energy storage unit to the ground converter station through the direct-current bus, and feeding back electric energy to the medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct-current power grid or feeding back the electric energy to the high-voltage power grid.

The processor executes the program and further realizes the following steps: the method comprises the steps that a two-port MMC converter of the ground converter station is controlled to obtain electric energy from a medium-voltage direct-current power grid so as to supply power to a long stator of the maglev train, wherein the electric energy obtained from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid. The device herein may be a server, a PC, a PAD, a mobile phone, etc.

The present application further provides a computer program product adapted to perform a program for initializing the following method steps when executed on a data processing device: judging whether renewable energy sources and the battery energy storage unit are in a shutdown state, wherein the renewable energy sources comprise: a photovoltaic power plant and a wind power plant; if the renewable energy source and the battery energy storage unit are not in a shutdown state, determining a power supply strategy based on the output power of the renewable energy source and the output power of the battery energy storage unit; and adopting the power supply strategy to supply power to the long stator of the magnetic suspension train.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are the same as the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, and supplying power to the long stator of the magnetic suspension train through the output of the ground converter station.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are smaller than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the renewable energy source and the output power of the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously acquiring electric energy from a medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station to complement the energy demand lacking in the maglev train, wherein the electric energy acquired from the medium-voltage direct current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct current power grid.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: determining a power supply strategy based on the renewable energy source and the output power of the battery energy storage unit comprises: if the output power of the renewable energy source and the output power of the battery energy storage unit are larger than the required energy of the magnetic suspension train, determining a power supply strategy as follows: and transmitting the output power of the renewable energy source and the battery energy storage unit to the ground converter station through the direct current bus, supplying power to a long stator of the maglev train through the output of the ground converter station, and simultaneously feeding back electric energy to the medium-voltage direct current power grid through controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or feeding back the electric energy to the high-voltage power grid.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: and if the renewable energy source and the battery energy storage unit are in a shutdown state, acquiring electric energy from a medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the maglev train, wherein the electric energy acquired from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: if the renewable energy source and the battery energy storage unit are not in a shutdown state and the maglev train is in an unoperated state, the output power of the renewable energy source and the battery energy storage unit is transmitted to the ground converter station through the direct current bus, and electric energy is fed back to the medium-voltage direct current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct current power grid or fed back to the high-voltage power grid.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: if the maglev train is in a regenerative braking working condition, transmitting regenerative braking power output by the maglev train to the ground converter station, transmitting the output of the ground converter station to a medium-voltage direct-current power grid, simultaneously transmitting the renewable energy and the output power of the battery energy storage unit to the ground converter station through the direct-current bus, and feeding back electric energy to the medium-voltage direct-current power grid by controlling a three-port MMC converter of the ground converter station, wherein the fed-back electric energy is used for other loads of the medium-voltage direct-current power grid or feeding back the electric energy to the high-voltage power grid.

When executed on a data processing device, is further adapted to perform a procedure for initializing the following method steps: the method comprises the steps that electric energy is obtained from a medium-voltage direct-current power grid through controlling a three-port MMC converter of the ground converter station so as to supply power to a long stator of the magnetic suspension train, wherein the electric energy obtained from the medium-voltage direct-current power grid comes from a high-voltage power grid or other power generation devices connected to the medium-voltage direct-current power grid.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.