阅读说明：本技术 一种三相动车组牵引传动供电系统 (Traction transmission power supply system of three-phase motor train unit ) 是由 王永建 钟磊 张伟鹏 吴波 于 2021-10-18 设计创作，主要内容包括：本发明提供了一种三相动车组牵引传动供电系统,包括：三相整流装置,包括三相交流输入端口和三组直流输出端口组,每组直流输出端口组包括n个直流输出端口,其中,n≥1,n的数量根据外部三相电源电压等级设置；DC/DC变换装置,包括3n个独立电力电子变压器,每个电力电子变压器的输入端口对应连接所述三相整流装置的一个直流输出端口,每个电力电子变压器的输出端口并联后作为所述DC/DC变换装置的直流输出端口；牵引逆变装置,所述牵引逆变装置的输入端口与所述DC/DC变换装置的直流输出端口连接,所述牵引逆变装置的输出端口与牵引电机电连接。本发明直接通过三相整流装置从外部电源取电驱动牵引电机,可以取消车载牵引变压器,并且可以根据不同电压等级设置n的取值,适用的电压等级范围广。(The invention provides a traction transmission power supply system of a three-phase motor train unit, which comprises: the three-phase rectifying device comprises a three-phase alternating current input port and three groups of direct current output port groups, wherein each group of direct current output port group comprises n direct current output ports, n is more than or equal to 1, and the number of n is set according to the voltage level of an external three-phase power supply; the DC/DC conversion device comprises 3n independent power electronic transformers, wherein the input port of each power electronic transformer is correspondingly connected with one DC output port of the three-phase rectifying device, and the output port of each power electronic transformer is connected in parallel and then used as the DC output port of the DC/DC conversion device; and an input port of the traction inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the traction inverter is electrically connected with a traction motor. The traction motor is directly driven by taking electricity from an external power supply through the three-phase rectifying device, a vehicle-mounted traction transformer can be omitted, the value of n can be set according to different voltage grades, and the applicable voltage grade range is wide.)

1. The utility model provides a three-phase EMUs traction drive power supply system which characterized in that includes:

the three-phase rectifying device comprises a three-phase alternating current input port and three groups of direct current output port groups, wherein each group of direct current output port group comprises n direct current output ports, and n is more than or equal to 1;

the DC/DC conversion device comprises 3n independent power electronic transformers, wherein the input port of each power electronic transformer is correspondingly connected with one DC output port of the three-phase rectifying device, and the output port of each power electronic transformer is connected in parallel and then used as the DC output port of the DC/DC conversion device;

and an input port of the traction inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the traction inverter is electrically connected with a traction motor.

2. The traction, transmission and power supply system of the three-phase motor train unit according to claim 1, wherein the three-phase rectifying device comprises three groups of H-bridge cascaded rectifiers, each group of H-bridge cascaded rectifiers comprises n single-phase rectifiers, input ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers are cascaded to form an input terminal 1 and an input terminal 2, the three input terminals 1 are connected with each other, the three input terminals 2 jointly form a three-phase alternating current input port of the three-phase rectifying device, and output ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers jointly form a group of direct current output ports of the three-phase rectifying device.

3. The traction transmission power supply system of the three-phase motor train unit according to claim 2, wherein the value of n is determined according to the voltage level of an external three-phase power supply and the rated input voltage of the single-phase rectifier.

4. The traction transmission power supply system of the three-phase motor train unit according to claim 1, further comprising an auxiliary inverter, wherein an input port of the auxiliary inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the auxiliary inverter is electrically connected with an auxiliary device.

5. The traction transmission power supply system of the three-phase motor train unit according to claim 1, wherein a three-phase alternating current input port of the three-phase rectifying device is connected with a reactor in series.

6. The traction, transmission and power supply system of three-phase motor train unit according to claim 1, wherein the power electronic transformer comprises a single-phase full-bridge inverter, a high-frequency transformer and a single-phase full-bridge rectifier which are connected in sequence, a direct current input port of the single-phase full-bridge inverter is used as an input port of the power electronic transformer, and a direct current output port of the single-phase full-bridge rectifier is used as an output port of the power electronic transformer.

7. The traction, transmission and power supply system of the three-phase motor train unit according to claim 6, wherein a reactor and a capacitor are connected between the output port of the single-phase full-bridge inverter and the primary side of the high-frequency transformer, and a reactor and a capacitor are connected between the secondary side of the high-frequency transformer and the input port of the single-phase full-bridge rectifier.

8. The traction, transmission and power supply system of the three-phase motor train unit according to claim 6, wherein the capacitor is connected in parallel to the direct current input port of the single-phase full-bridge inverter, and the capacitor is connected in parallel to the direct current output port of the single-phase full-bridge rectifier.

9. The traction transmission power supply system of the three-phase motor train unit according to claim 1, wherein the power electronic transformer comprises a single-phase half-bridge inverter, a high-frequency transformer and a single-phase half-bridge rectifier which are connected in sequence, a direct current input port of the single-phase half-bridge inverter is used as an input port of the power electronic transformer, and a direct current output port of the single-phase half-bridge rectifier is used as an output port of the power electronic transformer.

10. The traction transmission power supply system of the three-phase motor train unit according to claim 9, wherein a reactor and a capacitor are connected between the output port of the single-phase half-bridge inverter and the primary side of the high-frequency transformer, and a reactor and a capacitor are connected between the secondary side of the high-frequency transformer and the input port of the single-phase half-bridge rectifier.

Technical Field

The invention relates to the technical field of electrified railways and urban rails, in particular to a traction transmission power supply system of a three-phase motor train unit.

Background

Compared with a direct current traction motor, the alternating current traction motor has the advantages of high power density, low price, simplicity, reliability, good anti-idling performance and the like, so that the alternating current traction motor is replacing the direct current motor to become a main power source for traction of a trunk electrified railway and urban rail transit. The electrified railway adopts single-phase power supply, and an alternating current traction motor on an electric locomotive or a motor train unit needs to be driven by a three-phase inverter. In order to realize the conversion function, an electric locomotive or a motor train unit is provided with an AC-DC-AC traction converter, namely, single-phase AC is converted into DC, then the DC is converted into three-phase AC through an inverter, and the speed regulation is realized through voltage regulation and frequency regulation. The rated voltage of the traction bus of the existing electrified railway power supply system is 27.5kV, the highest voltage reaches 31kV, and the electric locomotive and the motor train unit are provided with vehicle-mounted traction transformers because of the limitation of the rated voltage of power electronic devices, and the voltage of a traction network is firstly reduced and then supplied to a traction converter. However, the volume and the weight of the vehicle-mounted traction transformer are large, the axle weight of a locomotive or a motor train unit is increased, the loss is increased, the efficiency is reduced, the power density is influenced, and the further increase of the speed of the motor train unit is restricted.

In order to cancel a vehicle-mounted traction transformer, the applicant applies 'a traction transmission power supply system for a motor train unit' (202011206524.8), but the application scheme is only suitable for a traction power supply system with single-phase traction power supply and lower contact network voltage, and considering that under the condition that the power supply capacity (capability) is the same, a three-phase generator, a motor and a power transmission line are more material-saving than the manufacture and construction of single-phase similar elements, the three-phase traction power supply system is simple in structure and excellent in performance, and therefore the three-phase traction power supply system is expected to replace the single-phase traction power supply system to become a new traction power supply system.

Disclosure of Invention

The invention aims to provide a traction transmission power supply system of a three-phase motor train unit, which directly takes electricity from an external power supply through a three-phase rectifying device to drive a traction motor, can cancel a vehicle-mounted traction transformer, can set the value of n according to different voltage grades, and has wide application range.

The invention is realized by the following technical means:

a traction transmission power supply system of a three-phase motor train unit comprises:

the three-phase rectifying device comprises a three-phase alternating current input port and three groups of direct current output port groups, wherein each group of direct current output port group comprises n direct current output ports, and n is more than or equal to 1;

the DC/DC conversion device comprises 3n independent power electronic transformers, wherein the input port of each power electronic transformer is correspondingly connected with one DC output port of the three-phase rectifying device, and the output port of each power electronic transformer is connected in parallel and then used as the DC output port of the DC/DC conversion device;

and an input port of the traction inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the traction inverter is electrically connected with a traction motor.

Further, the three-phase rectifying device comprises three groups of H-bridge cascaded rectifiers, each group of H-bridge cascaded rectifiers comprises n single-phase rectifiers, input ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers are cascaded to form an input terminal 1 and an input terminal 2, the three input terminals 1 are connected with each other, the three input terminals 2 jointly form a three-phase alternating current input port of the three-phase rectifying device, and output ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers jointly form a group of direct current output ports of the three-phase rectifying device.

Furthermore, the value of n is determined according to the voltage level of an external three-phase power supply and the rated input voltage of the single-phase rectifier.

Furthermore, the DC/DC conversion device also comprises an auxiliary inverter, wherein an input port of the auxiliary inverter is connected with a DC output port of the DC/DC conversion device, and an output port of the auxiliary inverter is electrically connected with auxiliary equipment.

Further, a three-phase alternating current input port of the three-phase rectifying device is connected in series with a reactor.

Further, the power electronic transformer comprises a single-phase full-bridge inverter, a high-frequency transformer and a single-phase full-bridge rectifier which are connected in sequence, a direct current input port of the single-phase full-bridge inverter serves as an input port of the power electronic transformer, and a direct current output port of the single-phase full-bridge rectifier serves as an output port of the power electronic transformer.

Further, a reactor and a capacitor are connected between the output port of the single-phase full-bridge inverter and the primary side of the high-frequency transformer, and a reactor and a capacitor are connected between the secondary side of the high-frequency transformer and the input port of the single-phase full-bridge rectifier.

Further, a capacitor is connected in parallel to a direct current input port of the single-phase full-bridge inverter, and a capacitor is connected in parallel to a direct current output port of the single-phase full-bridge rectifier.

Further, the power electronic transformer comprises a single-phase half-bridge inverter, a high-frequency transformer and a single-phase half-bridge rectifier which are connected in sequence, wherein a direct current input port of the single-phase half-bridge inverter is used as an input port of the power electronic transformer, and a direct current output port of the single-phase half-bridge rectifier is used as an output port of the power electronic transformer.

Further, a reactor and a capacitor are connected between the output port of the single-phase half-bridge inverter and the primary side of the high-frequency transformer, and a reactor and a capacitor are connected between the secondary side of the high-frequency transformer and the input port of the single-phase half-bridge rectifier.

Compared with the prior art, the invention has the beneficial effects that: the traction motor is suitable for a three-phase traction power supply system, the traction motor is directly driven by taking electricity from an external three-phase power supply (a three-phase traction network or a three-phase contact network) through a three-phase rectifying device, a vehicle-mounted traction transformer can be omitted, the value of n can be set according to different voltage grades, and the applicable voltage grade range is wide;

compared with the traditional traction transformer, the power electronic transformer is small in size and light in weight, is applied to a traction transmission power supply system of a motor train unit, and can reduce the space occupied by equipment and reduce the axle weight; in addition, the power electronic transformer is adopted, so that the transmission of voltage fluctuation, distortion and harmonic waves can be effectively isolated, and the decoupling of the power grid side and the load side is realized;

and thirdly, applying the power electronic transformer to a three-phase train traction transmission system to realize locomotive traction, and is a selection scheme of the three-phase train traction transmission system.

Drawings

Fig. 1 is a schematic structural diagram of a traction transmission power supply system of a three-phase motor train unit according to an exemplary embodiment.

Fig. 2 is a schematic diagram of a power electronic transformer using a full-bridge configuration according to an exemplary embodiment.

Fig. 3 is a schematic diagram of a power electronic transformer using a half-bridge configuration according to an exemplary embodiment.

Detailed Description

In order to make the technical solutions of the present invention better understood, those skilled in the art will further describe the present invention with reference to the accompanying drawings and the detailed description.

Examples

As shown in fig. 1, the present embodiment provides a traction transmission power supply system for a three-phase motor train unit, including:

the three-phase rectifying device comprises a three-phase alternating current input port and three groups of direct current output port groups, wherein each group of direct current output port group comprises n direct current output ports, and n is more than or equal to 1;

the DC/DC conversion device comprises 3n independent power electronic transformers, wherein the input port of each power electronic transformer is correspondingly connected with one DC output port of the three-phase rectifying device, and the output port of each power electronic transformer is connected in parallel and then used as the DC output port of the DC/DC conversion device;

and an input port of the traction inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the traction inverter is electrically connected with a traction motor.

Here, the 3n independent power electronic transformers in the DC/DC converter device can be regarded as 3 groups of power electronic transformer banks, each group of power electronic transformer banks includes n independent power electronic transformers, and the 3 groups of power electronic transformer banks respectively correspond to the 3 groups of DC output ports in the three-phase rectifier device, that is, the input port of each power electronic transformer corresponds to one DC output port of the three-phase rectifier device.

When the three-phase power supply system is implemented, the three-phase rectifying device gets power from an external three-phase power supply, the external three-phase power supply can be a three-phase traction network or a three-phase contact network in a three-phase traction power supply system, the three-phase traction network or the three-phase contact network can be a three-phase overhead line and also can be a three-phase rail laid on the ground, the voltage level of the external three-phase power supply (the voltage level of the three-phase traction network or the three-phase contact network) is set according to actual conditions, different n values are set according to different external three-phase power supply voltage levels, and the application range is wide.

Preferably, the three-phase rectifying device includes three groups of H-bridge cascaded rectifiers, each group of H-bridge cascaded rectifiers includes n single-phase rectifiers, input ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers are cascaded to form an input terminal 1 and an input terminal 2, the three input terminals 1 are connected with each other, the three input terminals 2 jointly form a three-phase ac input port of the three-phase rectifying device, and output ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers jointly form a group of dc output ports of the three-phase rectifying device.

Here, after the input ports of the n single-phase rectifiers of each group of H-bridge cascaded rectifiers are cascaded, 1 input terminal 1 and 1 input terminal 2 are formed, that is, the three groups of H-bridge cascaded rectifiers include 3 input terminals 1 and 3 input terminals 2, the 3 input terminals 1 are connected to each other, and the 3 input terminals 2 together form a three-phase ac input port of the three-phase rectifying apparatus.

Preferably, the value of n is determined according to the voltage level of an external three-phase power supply and the rated input voltage of the single-phase rectifier. As an example, the input voltage class of the external three-phase power supply voltage may be 10kV, 6kV, 4.5kV, 3.5kV, 3kV, or the like.

Here, the power electronic devices in the single-phase rectifier may be IGBTs, MOSFETs, GTRs, thyristors, etc., and the single-phase rectifier may select power electronic devices of different voltage classes, and set a corresponding n value (the number of single-phase rectifiers of the H-bridge cascade rectifier) according to the external three-phase power supply voltage class, so that the input voltage class of the three-phase rectifier device is adapted to the external three-phase power supply voltage class, thereby increasing the voltage class use range.

Preferably, the inverter further comprises an auxiliary inverter, an input port of the auxiliary inverter is connected with a direct current output port of the DC/DC conversion device, and an output port of the auxiliary inverter is electrically connected with an auxiliary device.

Preferably, a reactor is connected in series to a three-phase ac input port of the three-phase rectifier device.

Preferably, as shown in fig. 2, the power electronic transformer includes a single-phase full-bridge inverter, a high-frequency transformer and a single-phase full-bridge rectifier connected in sequence, a dc input port of the single-phase full-bridge inverter is used as an input port of the power electronic transformer, and a dc output port of the single-phase full-bridge rectifier is used as an output port of the power electronic transformer.

Preferably, a reactor and a capacitor are connected between the output port of the single-phase full-bridge inverter and the primary side of the high-frequency transformer, and a reactor and a capacitor are connected between the secondary side of the high-frequency transformer and the input port of the single-phase full-bridge rectifier. Here, the reactor and the capacitor can be connected in series to form a series resonance unit, so that the eddy current loss of the winding of the medium-high frequency transformer can be reduced, and the efficiency of the power electronic transformer is further improved.

Preferably, a capacitor is connected in parallel to a dc input port of the single-phase full-bridge inverter, and a capacitor is connected in parallel to a dc output port of the single-phase full-bridge rectifier.

As another preferred mode, as shown in fig. 3, the power electronic transformer includes a single-phase half-bridge inverter, a high-frequency transformer, and a single-phase half-bridge rectifier connected in sequence, wherein a dc input port of the single-phase half-bridge inverter is an input port of the power electronic transformer, and a dc output port of the single-phase half-bridge rectifier is an output port of the power electronic transformer.

Preferably, a reactor and a capacitor are connected between an output port of the single-phase half-bridge inverter and a primary side of the high-frequency transformer, and a reactor and a capacitor are connected between a secondary side of the high-frequency transformer and an input port of the single-phase half-bridge rectifier.

The above is only a preferred embodiment of the present invention, and it should be noted that the above preferred embodiment should not be considered as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. To those skilled in the art, it is possible to make various modifications and alterations without departing from the spirit and scope of the present invention, and such modifications and alterations should also be considered as the protection scope of the present invention.