阅读说明：本技术 一种长定子直线同步电机的供电系统及方法 (Power supply system and method for long-stator linear synchronous motor ) 是由 梅文庆 廖武 文宇良 南永辉 石煜 赵岸峰 李程 杨胜 王成杰 李淼 于 2019-04-10 设计创作，主要内容包括：本发明公开了一种长定子直线同步电机的供电系统及方法,包括：铺设于高速磁浮列车的运行轨道所在的地面上、与铺设于运行轨道上的长定子直线同步电机连接的N个变流器,N为大于1的整数；与N个变流器一一连接的N个分控制器；与N个分控制器连接的主控制器,用于根据高速磁浮列车的牵引需求电流对各变流器进行电流分配,并利用各分控制器相应控制各变流器的输出电流达到各自的电流分配值。可见,本申请由多个变流器同时为长定子直线同步电机供电,从而可满足高速磁浮列车的高速运行需求；且当一个变流器出现故障时,其余变流器可继续供电,从而提高了系统的容错能力,且保证了高速磁浮列车继续运行,进而提高了高速磁浮列车的安全性和可靠性。(The invention discloses a power supply system and a power supply method for a long-stator linear synchronous motor, wherein the power supply system comprises the following steps: the N converters are laid on the ground where the running track of the high-speed maglev train is located and connected with the long stator linear synchronous motor laid on the running track, and N is an integer greater than 1; n sub-controllers connected with the N converters one by one; and the main controller is connected with the N sub-controllers and used for carrying out current distribution on each converter according to the traction demand current of the high-speed maglev train and correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller. Therefore, the power is supplied to the long stator linear synchronous motor by the plurality of converters simultaneously, so that the high-speed running requirement of the high-speed magnetic suspension train can be met; when one converter fails, the other converters can continue to supply power, so that the fault tolerance of the system is improved, the high-speed maglev train is ensured to continue to run, and the safety and the reliability of the high-speed maglev train are improved.)

1. A power supply system for a long stator linear synchronous motor, comprising:

the system comprises N converters which are laid on the ground where a running track of the high-speed magnetic-levitation train is located and connected with a long stator linear synchronous motor laid on the running track, wherein N is an integer greater than 1;

the N sub-controllers are connected with the N converters one by one;

and the main controller is connected with the N sub-controllers and used for carrying out current distribution on the converters according to the traction demand current of the high-speed magnetic-levitation train and correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

2. The power supply system of a long-stator linear synchronous motor according to claim 1, wherein the main controller includes:

the current distribution module is used for distributing current to each converter according to the traction demand current of the high-speed magnetic-levitation train under the condition that the total loss power of a feeder cable connected between the long-stator linear synchronous motor and each converter is minimum;

and the current control module is used for correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

3. The power supply system of long stator linear synchronous motor according to claim 2, characterized in that when said high speed maglev train adopts I_dWhen the vector control strategy is 0, the current distribution module comprises:

the resistance calculating submodule is used for calculating the equivalent resistance of a feed cable connected between each converter and the long stator linear synchronous motor according to the running position of the high-speed magnetic suspension train;

an optimal distribution submodule for distributing the power according to the relation of total lossAnd the constraint condition that the total power loss is minimum, and current distribution is carried out on each converter; wherein p is_loss(x) For said total power loss, Iq_NFor current distribution, R, of the Nth converter_N(x) The equivalent resistance of a feed cable connected between the Nth converter and the long stator linear synchronous motor.

4. The power supply system of a long stator linear synchronous motor according to claim 3, wherein the current control module comprises:

the common part calculation submodule is used for calculating a common value of each two-phase mathematical model according to a common relational expression contained in the two-phase mathematical model of each converter under a two-phase rotating coordinate system;

correspondingly, each of the sub-controllers includes:

the coordinate transformation module is used for acquiring the driving position and the motor rotating speed of the long stator linear synchronous motor from the main controller, and converting a three-phase mathematical model of the target converter in a three-phase static coordinate system into a two-phase rotating coordinate system according to the driving position and the motor rotating speed to obtain the two-phase mathematical model of the target converter in the two-phase rotating coordinate system; the target converter is connected with the sub-controller to which the coordinate transformation module belongs;

and the converter control module is used for solving a target voltage value of the target converter in a two-phase rotating coordinate system according to the public value and a two-phase mathematical model of the target converter in the two-phase rotating coordinate system, and controlling the output current of the target converter to reach a current distribution value of the target converter under the condition that the output voltage of the target converter meets the target voltage value.

5. The power supply system of a long-stator linear synchronous motor according to any one of claims 1 to 4, wherein each of said sub-controllers is further configured to transmit fault information of a faulty converter to said main controller when detecting that the converter connected thereto is faulty;

correspondingly, the main controller is further configured to determine a fault converter and a normal converter according to the fault information, perform current distribution on each normal converter according to the traction demand current of the high-speed maglev train again, and correspondingly control the output current of each normal converter to reach respective current distribution value by using the sub-controller corresponding to each normal converter.

6. The power supply system of a long-stator linear synchronous motor according to claim 5, further comprising:

and the transmission module is connected with the main controller and is used for transmitting the fault information of the fault current transformer to an upper management system of the power supply system.

7. The power supply system of a long-stator linear synchronous motor according to claim 6, wherein the transmission module is embodied as a wireless transmission module or a wired transmission module.

8. The power supply system of a long-stator linear synchronous motor according to claim 6, wherein the fault information includes an installation position of the fault current transformer and a fault occurrence time.

9. A power supply method for a long-stator linear synchronous motor is characterized by comprising the following steps:

the method comprises the following steps of laying N converters on the ground where a running track of the high-speed magnetic-levitation train is located in advance, wherein N is an integer larger than 1;

distributing current to each converter according to the traction demand current of the high-speed maglev train;

and controlling the output current of each converter to reach respective current distribution value according to the current distribution result so as to supply power to the long stator linear synchronous motor laid on the operation track by each converter together.

10. The method for supplying power to a long-stator linear synchronous motor according to claim 9, wherein the step of distributing the current to each converter according to the traction demand current of the high-speed maglev train comprises:

and under the condition that the total loss power of a feeder cable connected between the long stator linear synchronous motor and each converter is minimum, current distribution is carried out on each converter according to the traction demand current of the high-speed magnetic suspension train.

Technical Field

The invention relates to the field of high-speed magnetic levitation traction rotation, in particular to a power supply system and method of a long-stator linear synchronous motor.

Background

At present, high-speed maglev trains are increasingly widely applied due to the advantages of high speed, low energy consumption, large transportation capacity, suitability for long-distance high-speed transportation and the like. In the prior art, a high-speed maglev train usually adopts a single-end power supply mode to supply power, namely, a converter supplies power to a long stator linear synchronous motor serving as a traction power source of the high-speed maglev train through a feed cable. However, when the high-speed maglev train runs at a high speed and needs a large acceleration, the current bearing capacity of one converter cannot meet the actual traction requirement of the high-speed maglev train, so that the running of the high-speed maglev train is limited; and when the converter breaks down, the high-speed maglev train cannot continuously run, so that the safety and the reliability of the high-speed maglev train are reduced.

Therefore, how to provide a solution to the above technical problem is a problem that needs to be solved by those skilled in the art.

Disclosure of Invention

The invention aims to provide a power supply system and a power supply method for a long-stator linear synchronous motor, wherein a plurality of converters are used for supplying power to the long-stator linear synchronous motor at the same time, so that the high-speed running requirement of a high-speed magnetic suspension train can be met; when one converter fails, the other converters can continue to supply power, so that the fault tolerance of the system is improved, the high-speed maglev train is ensured to continue to run, and the safety and the reliability of the high-speed maglev train are improved.

In order to solve the above technical problem, the present invention provides a power supply system for a long stator linear synchronous motor, including:

the system comprises N converters which are laid on the ground where a running track of the high-speed magnetic-levitation train is located and connected with a long stator linear synchronous motor laid on the running track, wherein N is an integer greater than 1;

the N sub-controllers are connected with the N converters one by one;

and the main controller is connected with the N sub-controllers and used for carrying out current distribution on the converters according to the traction demand current of the high-speed magnetic-levitation train and correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

Preferably, the main controller includes:

the current distribution module is used for distributing current to each converter according to the traction demand current of the high-speed magnetic-levitation train under the condition that the total loss power of a feeder cable connected between the long-stator linear synchronous motor and each converter is minimum;

and the current control module is used for correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

Preferably, when the high-speed maglev train adopts I_dWhen the vector control strategy is 0, the current distribution module comprises:

the resistance calculating submodule is used for calculating the equivalent resistance of a feed cable connected between each converter and the long stator linear synchronous motor according to the running position of the high-speed magnetic suspension train;

an optimal distribution submodule for distributing the power according to the relation of total loss

And the constraint condition that the total power loss is minimum, and current distribution is carried out on each converter; wherein p is_loss(x) For the purpose of the total power loss, the power loss,for current distribution, R, of the Nth converter_N(x) The equivalent resistance of a feed cable connected between the Nth converter and the long stator linear synchronous motor.

Preferably, the current control module includes:

the common part calculation submodule is used for calculating a common value of each two-phase mathematical model according to a common relational expression contained in the two-phase mathematical model of each converter under a two-phase rotating coordinate system;

correspondingly, each of the sub-controllers includes:

the coordinate transformation module is used for acquiring the driving position and the motor rotating speed of the long stator linear synchronous motor from the main controller, and converting a three-phase mathematical model of the target converter in a three-phase static coordinate system into a two-phase rotating coordinate system according to the driving position and the motor rotating speed to obtain the two-phase mathematical model of the target converter in the two-phase rotating coordinate system; the target converter is connected with the sub-controller to which the coordinate transformation module belongs;

and the converter control module is used for solving a target voltage value of the target converter in a two-phase rotating coordinate system according to the public value and a two-phase mathematical model of the target converter in the two-phase rotating coordinate system, and controlling the output current of the target converter to reach a current distribution value of the target converter under the condition that the output voltage of the target converter meets the target voltage value.

Preferably, each sub-controller is further configured to send fault information of a fault converter to the main controller when detecting that a converter connected to the sub-controller has a fault;

correspondingly, the main controller is further configured to determine a fault converter and a normal converter according to the fault information, perform current distribution on each normal converter according to the traction demand current of the high-speed maglev train again, and correspondingly control the output current of each normal converter to reach respective current distribution value by using the sub-controller corresponding to each normal converter.

Preferably, the power supply system further includes:

and the transmission module is connected with the main controller and is used for transmitting the fault information of the fault current transformer to an upper management system of the power supply system.

Preferably, the transmission module is a wireless transmission module or a wired transmission module.

Preferably, the fault information includes an installation location and a fault occurrence time of the faulty converter.

In order to solve the technical problem, the invention also provides a power supply method of the long stator linear synchronous motor, which comprises the following steps:

the method comprises the following steps of laying N converters on the ground where a running track of the high-speed magnetic-levitation train is located in advance, wherein N is an integer larger than 1;

distributing current to each converter according to the traction demand current of the high-speed maglev train;

and controlling the output current of each converter to reach respective current distribution value according to the current distribution result so as to supply power to the long stator linear synchronous motor laid on the operation track by each converter together.

Preferably, the process of current distribution to each converter according to the traction demand current of the high-speed maglev train specifically comprises:

and under the condition that the total loss power of a feeder cable connected between the long stator linear synchronous motor and each converter is minimum, current distribution is carried out on each converter according to the traction demand current of the high-speed magnetic suspension train.

The invention provides a power supply system of a long stator linear synchronous motor, which comprises: the N converters are laid on the ground where the running track of the high-speed maglev train is located and connected with the long stator linear synchronous motor laid on the running track, wherein N is an integer greater than 1; n sub-controllers connected with the N converters one by one; and the main controller is connected with the N sub-controllers and used for carrying out current distribution on each converter according to the traction demand current of the high-speed maglev train and correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

Therefore, the power is supplied to the long-stator linear synchronous motor by the plurality of converters, and the sum of the output currents of the plurality of converters can reach the traction demand current of the high-speed magnetic-levitation train, so that the high-speed running demand of the high-speed magnetic-levitation train is met; and when one of the converters fails, N-1 converters can still supply power, so that the fault tolerance of a power supply system is improved, the high-speed magnetic-levitation train is ensured to continue to run, and the safety and the reliability of the high-speed magnetic-levitation train are improved.

The invention also provides a power supply method of the long-stator linear synchronous motor, which has the same beneficial effect as the power supply system.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a power supply system of a long-stator linear synchronous motor according to an embodiment of the present invention;

fig. 2 is an equivalent circuit diagram of a power supply system of a long-stator linear synchronous motor according to an embodiment of the present invention;

fig. 3 is a flowchart of a power supply method for a long-stator linear synchronous motor according to an embodiment of the present invention.

Detailed Description

The core of the invention is to provide a power supply system and a method for a long stator linear synchronous motor, a plurality of converters simultaneously supply power to the long stator linear synchronous motor, thereby meeting the high-speed running requirement of a high-speed magnetic suspension train; when one converter fails, the other converters can continue to supply power, so that the fault tolerance of the system is improved, the high-speed maglev train is ensured to continue to run, and the safety and the reliability of the high-speed maglev train are improved.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. 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 invention.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a power supply system of a long-stator linear synchronous motor according to an embodiment of the present invention.

The power supply system of the long stator linear synchronous motor comprises:

the system comprises N converters 1 which are laid on the ground where a running track of the high-speed maglev train is located and connected with a long stator linear synchronous motor laid on the running track, wherein N is an integer greater than 1;

n sub-controllers 2 connected to the N converters 1 one by one;

and the main controller 3 is connected with the N sub-controllers 2 and is used for carrying out current distribution on each converter 1 according to the traction required current of the high-speed magnetic-levitation train and correspondingly controlling the output current of each converter 1 to reach respective current distribution value by using each sub-controller 2.

Specifically, the power supply system of the long stator linear synchronous motor of the application comprises a plurality of converters 1, a plurality of sub-controllers 2 and a main controller 3, and the working principle is as follows:

considering that the output current of the converter 1 cannot exceed the maximum output current limit, the current bearing capacity of a single converter 1 cannot meet the requirement of high-speed and high-reliability running of a high-speed magnetic-levitation train, so that the multi-end power supply mode is adopted, namely, a plurality of converters 1 supply power to a long stator linear synchronous motor serving as a traction power source of the high-speed magnetic-levitation train together, namely, the plurality of converters 1 share the traction required current of the high-speed magnetic-levitation train together, and the traction requirement of the high-speed magnetic-levitation train is met.

Because the long stator linear synchronous motor is laid on the running track of the high-speed maglev train, a plurality of converters 1 for supplying power to the long stator linear synchronous motor are laid on the ground where the running track of the high-speed maglev train is located, so that the long stator linear synchronous motor is convenient to supply power. As for the specific laying position of the plurality of current transformers 1 on the ground, in a word, the plurality of current transformers 1 may be placed at any position, but the present application considers that the laying position of the plurality of current transformers 1 is different, and the total transmission loss of the feeder cable connected between the plurality of current transformers 1 and the long stator linear synchronous motor is different, so the present application selects an appropriate position for the plurality of current transformers 1 under the condition of reducing the total transmission loss of the feeder cable as much as possible.

The present application also provides a sub-controller 2 for each converter 1, i.e. each converter 1 is controlled by an independent controller. It can be understood that the sub-controller 2 corresponding to any current transformer 1 should be arranged around the current transformer 1, so as to facilitate information interaction between the two. In the present application, one main controller 3 is provided for a plurality of sub-controllers 2, that is, the main controller 3 manages the plurality of sub-controllers 2 in a unified manner. Specifically, the main controller 3 performs current distribution on each converter 1 according to the traction demand current of the high-speed maglev train, so that the sum of the current distribution values of each converter 1 is equal to the traction demand current of the high-speed maglev train on the basis that each converter 1 does not exceed the maximum output current limit, and then the current distribution values of each converter 1 are correspondingly sent to each sub-controller 2 one by one, so that each sub-controller 2 is utilized to correspondingly control the output current of each converter 1 to reach the respective current distribution value.

In addition, it should be noted that the simplest structure of the power supply system of the present application is to lay two converters 1, but in the present application, it is considered that when one converter 1 fails, only one converter 1 may be left to supply power, so the power supply system of the present application usually chooses to lay more than two converters 1, that is, N is an integer greater than 2, and when one converter 1 fails, a plurality of converters 1 may still supply power, thereby further improving the fault tolerance of the power supply system.

The invention provides a power supply system of a long stator linear synchronous motor, which comprises: the N converters are laid on the ground where the running track of the high-speed maglev train is located and connected with the long stator linear synchronous motor laid on the running track, wherein N is an integer greater than 1; n sub-controllers connected with the N converters one by one; and the main controller is connected with the N sub-controllers and used for carrying out current distribution on each converter according to the traction demand current of the high-speed maglev train and correspondingly controlling the output current of each converter to reach respective current distribution value by using each sub-controller.

Therefore, the power is supplied to the long-stator linear synchronous motor by the plurality of converters, and the sum of the output currents of the plurality of converters can reach the traction demand current of the high-speed magnetic-levitation train, so that the high-speed running demand of the high-speed magnetic-levitation train is met; and when one of the converters fails, N-1 converters can still supply power, so that the fault tolerance of a power supply system is improved, the high-speed magnetic-levitation train is ensured to continue to run, and the safety and the reliability of the high-speed magnetic-levitation train are improved.

On the basis of the above-described embodiment:

as an alternative embodiment, the main controller 3 includes:

the current distribution module is used for distributing current to each converter 1 according to the traction demand current of the high-speed magnetic suspension train under the condition that the total loss power of a feed cable connected between the long-stator linear synchronous motor and each converter 1 is minimum;

and the current control module is used for correspondingly controlling the output current of each converter 1 to reach respective current distribution value by using each sub-controller 2.

Specifically, considering that each converter 1 is connected with the long-stator linear synchronous motor through a feed cable, and the output current of the converter 1 affects the loss power of the feed cable between the converter 1 and the long-stator linear synchronous motor, the main controller 3 of the present application should distribute the current of each converter 1 under the condition that the total loss power of the feed cable connected between the long-stator linear synchronous motor and each converter 1 is the minimum, so as to further optimize the performance of the power supply system.

As an alternative embodiment, when the high-speed maglev train adopts I_dWhen the vector control strategy is 0, the current distribution module comprises:

the resistance calculating submodule is used for calculating the equivalent resistance of a feed cable connected between each converter 1 and the long stator linear synchronous motor according to the running position of the high-speed maglev train;

an optimal distribution submodule for distributing the power according to the relation of total loss

And the constraint condition that the total power loss is minimum, and current distribution is carried out on each converter 1; wherein p is_loss(x) In order to be the total power loss,for the current distribution value, R, of the Nth converter 1_N(x) Is the equivalent resistance of a feeder cable connected between the nth current transformer 1 and the long stator linear synchronous motor.

In particular, high speed maglev trains generally employ I_dVector control strategy (I) of 0_dExcitation current of the long-stator linear synchronous motor under a two-phase rotating coordinate system), under the control strategy, the traction force of the high-speed magnetic suspension train is totally from the torque current Iq of the long-stator linear synchronous motor under the two-phase rotating coordinate system, and I_qProvided in common by the converters 1, i.e.

(

The output current of the nth converter 1).

The known converters 1 and lengthThe equivalent resistance of the feed cable connected between the stator linear synchronous motors is a function of the running position of the high-speed magnetic suspension train, and the equivalent resistance is assumed to be R respectively₁(x)、R₂(x)…R_N(x)(R_N(x) Equivalent resistance of a feeder cable connected between the Nth converter 1 and the long-stator linear synchronous motor, and x represents the running position of the train), so that the main controller 3 can calculate R after acquiring the running position of the high-speed magnetic suspension train₁(x)、R₂(x)…R_N(x)。

Based on this, the total power loss of the feed cable connected between the long stator linear synchronous motor and each converter 1 isThe constraint conditions are as follows:

the main controller 3 according to the optimal algorithm pairReasonable distribution is carried out to obtain p_loss(x) Is measured.

For example, taking N ═ 2 as an example, two converters 1 are disposed on the ground corresponding to two ends of the running track of the high-speed maglev train, assuming that the distance between the converters 1 at two ends is L, the distance between the high-speed maglev train and one of the converters 1 is X, the total equivalent resistance of the feeder cable connected between the long-stator linear synchronous motor and each converter 1 is R, and the required current for traction of the high-speed maglev train is I_qThe current distribution coefficient is

The total power loss of the feeder cable is then:

and (5) obtaining a derivative:

the following results were obtained when the total power loss was minimal:

assuming that both currents obtained according to the relational expression do not exceed the maximum current limit of the current transformer 1, the main controller 3 correspondingly distributes the currents to the two current transformers 1 according to the two currents; assuming a current obtained according to the above relation

The maximum current limit of the current transformer 1 is exceeded,if the maximum current limit of the converter 1 is not exceeded, the output currents of the two converters 1 are distributed as follows:

as an alternative embodiment, the current control module comprises:

the common part calculating submodule is used for calculating a common value of each two-phase mathematical model according to a common relational expression contained in the two-phase mathematical model of each converter 1 under the two-phase rotating coordinate system;

accordingly, each sub-controller 2 includes:

the coordinate transformation module is used for acquiring a running position and the motor rotating speed of the long stator linear synchronous motor from the main controller 3, and converting a three-phase mathematical model of the target converter under a three-phase static coordinate system into a two-phase rotating coordinate system according to the running position and the motor rotating speed to obtain a two-phase mathematical model of the target converter under the two-phase rotating coordinate system; the target converter is a converter 1 connected with a sub-controller 2 to which the coordinate transformation module belongs;

and the converter control module is used for solving a target voltage value of the target converter in the two-phase rotating coordinate system according to the public value and the two-phase mathematical model of the target converter in the two-phase rotating coordinate system, and controlling the output current of the target converter to reach the current distribution value of the target converter under the condition that the output voltage of the target converter meets the target voltage value.

Specifically, referring to fig. 2, fig. 2 is an equivalent circuit diagram of a power supply system of a long-stator linear synchronous motor according to an embodiment of the present invention.

The three-phase mathematical model of each converter 1 in the three-phase stationary coordinate system can be expressed as:

…

wherein u is_aN、u_bN、u_cNIs the abc three-phase output voltage, i, of the Nth converter 1_aN、i_bN、i_cNIs the abc three-phase output current, psi, of the Nth converter 1_a、ψ_b、ψ_cAbc three-phase stator flux linkage R of long-stator linear synchronous motor_sIs the stator resistance, R, of a long stator linear synchronous motor_cableNIs the equivalent resistance, L, of a feeder cable connected between the Nth converter 1 and the long stator linear synchronous motor_cableNIs the equivalent inductance of the feeder cable connected between the nth converter 1 and the long stator linear synchronous motor.

Respectively converting the three-phase mathematical model of each converter 1 in the three-phase stationary coordinate system into a two-phase rotating coordinate system, and obtaining the two-phase mathematical model of each converter 1 in the two-phase rotating coordinate system according to the orientation of the rotor magnetic field:

…

wherein u is_dN、u_qNIs the dq two-phase output voltage, i of the Nth converter 1_dN、i_qNIs the dq two-phase output current, L of the Nth converter 1_dD-axis inductance, L, for long stator linear synchronous machines_qQ-axis inductance, psi, for long stator linear synchronous machines_fMagnetic linkage, omega, generated for high-speed maglev trains_rIs the equivalent angular frequency of the long stator linear synchronous motor.

As can be seen from the two-phase mathematical model of each current transformer 1 in the two-phase rotating coordinate system, the two-phase mathematical model of each current transformer 1 includes the same common relation:

a simplified mathematical model of each converter 1 in a two-phase rotating coordinate system is obtained:

…

based on this, this application obtains the position of going of high-speed maglev train and the motor speed of long stator linear synchronous motor by main control unit 3, then sends the two to each minute controller 2. Each sub-controller 2 converts a three-phase mathematical model of a converter 1 (called a target converter) connected with the sub-controller per se under a three-phase static coordinate system into a two-phase rotating coordinate system according to the running position of the train and the rotating speed of the motor, so as to obtain a two-phase mathematical model (including dq two-phase output current of the target converter) of the target converter under the two-phase rotating coordinate system.

Then, each sub-controller 2 returns the dq two-phase output current of the target converter to the main controller 3, the main controller 3 stores the public relational expression included in the two-phase mathematical model of each converter 1 in advance, then substitutes the dq two-phase output current of each target converter into the public relational expression, calculates the public value of each two-phase mathematical model, and returns the public value to each sub-controller 2.

Each sub-controller 2 calculates a target voltage value of the target converter in the two-phase rotating coordinate system according to the common value and a simplified mathematical model of the target converter in the two-phase rotating coordinate system, and controls the output current of the target converter to reach the current distribution value of the target converter under the condition that the output voltage of the target converter meets the target voltage value.

As can be seen, the sub-controller 2 needs to quickly acquire voltage and current information (ac transmission) of the target converter, so a fast data exchange channel needs to be used between the sub-controller 2 and the target converter. And the sub-controller 2 and the main controller 3 transmit the dq-axis current component of the target converter, and the dq-axis current component is obtained through coordinate transformation and is expressed as direct current, so that the transmission speed requirement can be greatly reduced compared with the transmission of alternating current, and a slow data exchange channel can be adopted between the sub-controller 2 and the main controller 3.

As an optional embodiment, each sub-controller 2 is further configured to send fault information of a faulty converter to the main controller 3 when detecting that the converter 1 connected to itself is faulty;

correspondingly, the main controller 3 is further configured to determine the fault current transformer and the normal current transformers according to the fault information, perform current distribution on each normal current transformer according to the traction demand current of the high-speed maglev train again, and correspondingly control the output current of each normal current transformer to reach the respective current distribution value by using the sub-controller 2 corresponding to each normal current transformer.

Further, considering that the converter 1 may have a fault in the operation process, thereby affecting the normal operation of the whole power supply system, each sub-controller 2 of the present application may also detect whether the converter 1 connected to itself has a fault, and if the converter has a fault, send the fault information of the faulty converter to the main controller 3.

After receiving the fault information, the main controller 3 can distinguish the current transformer (fault current transformer) in the fault state and the current transformer (normal current transformer) in the normal operation state from all the current transformers 1 according to the fault information. Then, the main controller 3 distributes current to each normal converter again according to the traction demand current of the high-speed maglev train, and correspondingly controls the output current of each normal converter to reach respective current distribution value by using the sub-controllers 2 corresponding to each normal converter, thereby ensuring the normal operation of the whole power supply system.

It should be noted that if the sum of the output currents of the normal converters is not enough to provide the current required for the traction of the high-speed maglev train before the fault, the high-speed maglev train operates in a derated manner.

As an optional embodiment, the power supply system further comprises:

and the transmission module is connected with the main controller 3 and is used for transmitting the fault information of the fault current transformer to an upper management system of the power supply system.

Further, the power supply system of this application still includes transmission module, and its theory of operation is: the main controller 3 transmits the fault information of the fault current transformer to an upper management system of the power supply system by using the transmission module after receiving the fault information of the fault current transformer, so that a worker in the upper management system can know the relevant information of the fault current transformer in time, and the worker can conveniently perform subsequent maintenance work.

As an optional embodiment, the transmission module is specifically a wireless transmission module or a wired transmission module.

Specifically, the transmission module of this application can select for use wireless transmission module (like bluetooth module, WIFI module), also can select for use wired transmission module (like the OTN looped netowrk) to realize fault information's transmission.

As an alternative embodiment, the fault information includes the installation location of the faulty converter and the time of occurrence of the fault.

Specifically, the fault information of the application can include the installation position of the fault current transformer, so that a worker can conveniently locate the fault current transformer; the fault information may also include the time when the fault occurred in the faulty converter, so that the staff can know more about the faulty converter. Of course, the fault information may also include other information (such as the fault reason of the fault current transformer), and the application is not particularly limited herein.

Referring to fig. 3, fig. 3 is a flowchart of a power supply method for a long-stator linear synchronous motor according to an embodiment of the present invention.

The power supply method of the long-stator linear synchronous motor comprises the following steps:

step S1: n converters are paved on the ground where the running track of the high-speed maglev train is located in advance, wherein N is an integer larger than 1.

Step S2: and distributing current to each converter according to the traction demand current of the high-speed maglev train.

Step S3: and controlling the output current of each converter to reach respective current distribution value according to the current distribution result so as to supply power to the long stator linear synchronous motor laid on the operation track by each converter together.

As an optional embodiment, the process of performing current distribution on each converter according to the traction demand current of the high-speed maglev train specifically includes:

and under the condition of meeting the minimum total power loss of a feeder cable connected between the long stator linear synchronous motor and each converter, current distribution is carried out on each converter according to the traction demand current of the high-speed maglev train.

For introduction of the power supply method provided in the present application, reference is made to the embodiments of the power supply system described above, and details of the power supply method are not repeated herein.

It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, 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 a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.