CN111509866A - Multi-receiving-coil rail transit contactless power supply device with segmented transmitting coils - Google Patents

Abstract

A multi-receiving coil rail transit contactless power supply device with transmitting coil segments is characterized in that a transmitting coil laid along a rail is divided into a plurality of transmitting coil segments, and a receiving side comprises a plurality of receiving coils. The length of each transmitting coil segment is greater than the sum of the lengths of the plurality of receiving coils, and the end of each transmitting coil is at an angle. When a certain receiving coil moves to the position of the joint part of two adjacent transmitting coil sections, the induced voltage of the receiving coil is lower than the induced voltage of other receiving coils and is blocked by the rectifying circuit, and power is not supplied to a rear-stage load; when the receiving coil moves completely into the area of the next transmitting coil segment, the receiving coil continues to supply power to the rear-stage load. The number of the receiving coils is at least 1 more than the number N of the receiving coils without segmentation; the multi-receiving-coil rail transit contactless power supply device with the segmented transmitting coils can effectively improve the voltage output quality of the receiving coils when the receiving coils pass through the end positions of the transmitting coils, reduce the input and output fluctuation of a system and enhance the stability of the system.

Description

A contactless power supply device for rail transit with multiple receiving coils segmented by transmitting coils

technical field

The invention relates to a power supply device applied in the field of rail transit.

Background technique

Compared with pantograph and catenary or third rail power supply, the contactless power supply (WPT) system applied to rail transit has the advantages of being environmentally friendly, safe and reliable, and low maintenance cost.

A loosely coupled transformer is a key component of a contactless power supply system. Unlike hard electrical connections: wired methods, tightly coupled transformers, etc., there is an air gap between the transmitting and receiving coils of non-contact transformers. Due to the small permeability of non-ferromagnetic substances such as air, the magnetic circuit of non-contact transformer coils is magnetic. The resistance is large, the magnetic induction gain is small, and the coupling coefficient and energy transfer efficiency are low. For long-distance mobile contactless power supply applications, considering that the internal resistance of the coil is large at high frequencies, the length of the transmitting coil should not be too long, and the transmitting coil should be segmented to reduce the internal resistance of the coil and improve the system efficiency.

The receiving coil is generally installed at the bottom of the train and moves with the train. When the receiving coil moves to the section of the transmitting coil, the power supply of one section of the transmitting coil is switched to the power supply of the next section of the transmitting coil, that is, the receiving coil is over-segmented.

In the existing contactless power supply system applied to rail transit, the transmitting coil is laid in a rectangular form, as shown in Figure 1. During over-segmentation, the mutual inductance of the transmitting coil and the receiving coil first increases and then decreases, as shown in Figure 2. The fluctuation of mutual inductance causes the current of the parallel receiving coils to be unbalanced and the output fluctuates greatly. The voltage and current of the receiving coils with sudden increase in mutual inductance increase, and in severe cases, the current of the receiving coils is too large and burned. Therefore, the problem of over-segmentation of the contactless power supply system due to coil segmentation needs to be solved urgently.

In order to improve the output voltage quality and reduce the voltage fluctuation when the system is over-segmented, the document "Efficiencyoptimization for wireless dynamic charging system with overlapped DD coilarrays[C].Applied Power Electronics Conference and Exposition.IEEE, 2017:1439-1442." proposes to use Double-layer DD type structure, the length of the transmitting coil and the receiving coil are equal, and the output voltage can be controlled to be stable by controlling the current phase of the upper and lower coils of the transmitting coil, but this method requires laying a large number of coils, and the system is less economical. ChoiS, Huh J, Lee W Y, et al. Proposed in "New Cross-Segmented Power Supply Rails for Roadway-Powered Electric Vehicles[J].IEEE Transactions on Power Electronics,2013,28(12):5832-5841." The new segment compensation scheme switches the power supply section of the transmitting coil according to the position of the receiving coil to reduce the leakage inductance and power loss in the long power supply interval, but does not solve the switching problem of the long power supply interval.

The method of switching between multiple receiving coils can effectively solve the problem of over-segmentation between transmitting coil segments in long-distance applications. The processing method of the patent 201610200989.X for the receiving coil that moves to the over-section of the transmitting coil is to open two power supply coils at the same time to supply energy to the receiving coil. Due to the large change in the mutual inductance parameters of the system, the output power quality is poor, and the system efficiency is relatively high. Low.

SUMMARY OF THE INVENTION

The purpose of the present invention is to adapt to the characteristics of mobile long-distance contactless power supply, and to propose a rail transit contactless power supply device with a segmented transmitting coil and multiple receiving coils. The invention can effectively solve the problem of over-segmentation in the application of the long-distance contactless power supply system, and improve the quality of the output electric energy.

The technical scheme adopted by the present invention to solve the technical problem is as follows:

The contactless power supply device for rail transit includes ground equipment and vehicle-mounted mobile equipment. The ground equipment includes a high-frequency current source, a power bus, a control switch and a transmitting coil. The high-frequency current source is connected to the power bus, the transmitting coil is connected in series with the corresponding control switch, and the control switch is connected to the power bus. The vehicle-mounted mobile device includes a receiving coil, a compensation circuit for the receiving coil, a high-frequency rectifying device, a busbar supporting capacitor and a load. The receiving coil is connected with the receiving coil compensation circuit, the receiving coil compensation circuit is connected with the high-frequency rectifier, and the high-frequency rectifier is connected with the bus support capacitor to form a series branch; the output ends of the bus support capacitor are connected in parallel, and then connected to the load.

The transmitting coil is a multi-section structure, each section is laid in sequence along the track, and each section of the transmitting coil is connected to a high-frequency current source through a control switch. The end of the transmitting coil is an acute angle, and 0<actan(α)≤b/L is satisfied, where b is the length of the receiving coil along the moving direction, and L is the width of the transmitting coil. Since the end of the transmitting coil is at an angle α, the mutual inductance value between the transmitting coil and the receiving coil is not greater than the mutual inductance value when the receiving coil is completely located in the transmitting coil during over-segmentation.

The mutual inductance between the transmitting coil and the receiving coil at the cross section of the contactless power supply device for rail transit is small, and the induced voltage of the receiving coil is lower than that of other coils. The receiving coil is blocked by the high-frequency rectifier circuit and does not participate in power supply to the load. .

The receiving coils are installed on the bottom of the locomotive and are arranged in sequence along the track direction. Since the receiving coils at the over-segmented place do not participate in power supply to the load, the number of receiving coils is at least 1 more than the number of receiving coils N when there is no segmented power supply, as a backup for the system redundancy design; each receiving coil has the same structure, self-inductance and mutual inductance, etc. The electromagnetic parameters are the same. The length of each transmitting coil is much greater than the sum of the lengths of multiple receiving coils.

The power supply method of the contactless power supply device for rail transit is as follows:

The receiving coils follow the motion of the car. When the receiving coil is completely located in a certain section of the transmitting coil, the control switch connected to this section of the transmitting coil is closed, and the high-frequency current source corresponding to this section of the transmitting coil supplies power to the load; when the receiving coil is in the over-segment, the receiving coil The induced voltage is low, blocked by the high-frequency rectifier circuit, and does not supply power to the load; when the receiving coil moves to the next transmitting coil, the control switch corresponding to the transmitting coil is closed to supply power to the load. Since the number of receiving coils is at least one more than the number N of receiving coils when there is no segmented power supply, it is ensured that at least N receiving coils are connected to the circuit to supply power to the load at any position of the receiving coils.

Compared with the prior art, the beneficial effects of the present invention are:

1. In view of the large change of the mutual inductance of the original receiving coil when the receiving coil is over-segmented, which affects the output power quality, the method of blocking the receiving coil that is being over-segmented is adopted to improve the system output and improve the power quality.

2. By transforming the transmitting coil, the present invention bends the end of the transmitting coil at an appropriate angle. Compared with the method of controlling the current of the primary coil, the present invention has simple operation and strong practical applicability.

3. When the receiving coil is located at the connection of the transmitting coil, the current circulation can be blocked by the rectifier device, and no additional switching device is required.

Description of drawings

FIG. 1 is a schematic structural diagram of a loosely coupled transformer with no tilt at the end of a ground transmitting coil in the prior art;

Fig. 2 is a schematic diagram of the change of the mutual inductance of the non-inclined transmitting coil and the receiving coil at the end of the prior art with the relative position;

FIG. 3 is a schematic diagram of the positions of the receiving coils 51 , 52 and 53 of the device of the present invention all within the range of the first transmitting coil 41 ;

4 is a schematic diagram of the third receiving coil 53 of the device of the present invention in an over-segmented position;

5 is a schematic diagram of the second receiving coil 52 of the device of the present invention in an over-segmented position;

6 is a schematic diagram of the first receiving coil 51 of the device of the present invention in an over-segmented position;

FIG. 7 is a schematic diagram of the receiving coils 51 , 52 and 53 of the device of the present invention all being within the range of the second transmitting coil 42 ;

Fig. 8 The mutual inductance of the inclined transmitting coil and the receiving coil at the end changes with the relative position;

9 is a schematic circuit diagram of a contactless power supply device for rail transit with a segmented transmitter coil and multiple receiver coils.

Among them: high frequency current source 1, power bus 2, control switch 3, transmitting coil 4, receiving coil 5, receiving coil compensation circuit 6, high frequency rectifier 7, bus support capacitor 8, load 9, ground equipment 11, vehicle mobile Device 12, first control switch 31, second control switch 32, first transmit coil 41, second transmit coil 42, first receive coil 51, second receive coil 52, third receive coil 53, first receive coil compensation circuit 61, second receiving coil compensation circuit 62, third receiving coil compensation circuit 63, first high frequency rectifier 71, second high frequency rectifier 72, third high frequency rectifier 73, first bus support capacitor 81, The second busbar supports capacitor 82 and the third busbar supports capacitor 83 .

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

The contactless power supply device for rail transit of the present invention includes ground equipment and vehicle-mounted mobile equipment. The ground equipment includes a high-frequency current source, a power bus, a control switch and a transmitting coil. The high-frequency current source is connected to the power bus, the transmitting coil is connected in series with the corresponding control switch, and the control switch is connected to the power bus. The vehicle-mounted mobile device includes a receiving coil, a compensation circuit for the receiving coil, a high-frequency rectifying device, a busbar supporting capacitor and a load. The receiving coil is connected with the receiving coil compensation circuit, the receiving coil compensation circuit is connected with the high-frequency rectifier, and the high-frequency rectifier is connected with the bus support capacitor to form a series branch; the output ends of the bus support capacitor are connected in parallel, and then connected to the load. A plurality of receiving coils are installed on the bottom of the locomotive and are arranged in sequence along the track direction.

FIG. 9 shows a circuit of a contactless power supply device for rail transit with a segmented transmitter coil and multiple receiver coils according to Embodiment 1 of the present invention. The device includes ground equipment 11 and vehicle-mounted mobile equipment 12, and the ground equipment 11 transmits high-frequency power through a transmitting coil laid along the track. The vehicle-mounted mobile device 12 receives the high-frequency electrical energy emitted by the transmitting coil and converts it into electrical energy that can be used by the vehicle. The ground equipment 11 includes a high-frequency current source 1, a power bus 2, a control switch 3 and a transmitting coil 4, the high-frequency current source 1 is connected to the power bus 2, the transmitting coil 4 is connected in series with the corresponding control switch 3, and the control switch 3 Connect to power bus 2. The vehicle-mounted mobile device 12 of the device includes a receiving coil 5, a receiving coil compensation circuit 6, a high-frequency rectifying device 7, a busbar supporting capacitor 8 and a load 9. The receiving coil 5 is connected to the receiving coil compensation circuit 6, and the receiving coil compensation circuit 6 is connected. The high frequency rectifier 7 is connected with the bus support capacitor 8 to form a series branch; the output ends of the bus support capacitor 8 are connected in parallel and then connected to the load 9 .

The transmitting coils 4 are laid along the track, and the transmitting coils 4 in this embodiment are arranged in sequence in segments, which are a first transmitting coil 41 and a second transmitting coil 42 respectively.

The transmitting coil 4 is an AC power transmitting coil for ground equipment. The end of the transmitting coil is an acute angle, which satisfies 0<actan(α)≤b/L, where b is the length of the receiving coil along the moving direction, and L is the width of the transmitting coil. The change of the mutual inductance of the transmitting coil and the receiving coil with the relative position is shown in Figure 8. Since the end of the transmitting coil is at an angle α, the mutual inductance value between the transmitting coil and the receiving coil is not greater than the mutual inductance value when the receiving coil is completely located in the transmitting coil during over-segmentation.

As shown in FIG. 9 , the vehicle-mounted mobile device 12 includes a plurality of receiving coils 5 , which are respectively a first receiving coil 51 , a second receiving coil 52 , and a third receiving coil 53 in this embodiment. The dimensions and turns of the three receiving coils are The numbers are the same, and are sequentially arranged on the vehicle-mounted mobile device 12 along the direction of the guide rail. In this embodiment, only two receiving coils are required when there is no segmented power supply.

In the ground equipment, the high-frequency current source 1 is connected to the power bus 2, the transmitting coil 4 is connected to the corresponding control switch 3, and is connected to the power bus 2, wherein the first transmitting coil 41 is connected in series with the first control switch 31. To the power bus 2 , the second transmitting coil 42 is connected to the power bus 2 in series with the second control switch 32 .

The length of each transmitting coil is much greater than the sum of the lengths of multiple receiving coils.

In the vehicle-mounted mobile device 12 , the receiving coil compensation circuit 6 includes a first receiving coil compensation circuit 61 , a second receiving coil compensation circuit 62 and a third receiving coil compensation circuit 63 . The high-frequency rectifying device 7 includes a first high-frequency rectifying device 71 , a second high-frequency rectifying device 72 and a third high-frequency rectifying device 73 . The bus support capacitor 8 includes a first bus support capacitor 81 , a second bus support capacitor 82 and a third bus support capacitor 83 . The first receiving coil 51 , the first receiving coil compensation circuit 61 , the first high frequency rectifier 71 and the first bus support capacitor 81 are connected in series in sequence, and the second receiving coil 52 , the second receiving coil compensation circuit 62 , the second high frequency rectifier The device 72 and the second bus support capacitor 82 are connected in series in sequence, and the third receiving coil 53, the third receiving coil compensation circuit 63, the third high-frequency rectifier 73 and the third bus support capacitor 83 are connected in series in sequence to form three series branches; The output terminals of the first bus support capacitor 81 , the second bus support capacitor 82 and the third bus support capacitor 83 are connected in parallel to the load 9 .

The length of the first transmitting coil 41 and the second transmitting coil 42 is much greater than the sum of the lengths of the plurality of receiving coils.

The receiving coil compensation circuit 6 may be a series compensation circuit or a parallel compensation circuit composed of capacitors.

The high-frequency rectifier device 7 is a single-phase uncontrolled rectifier bridge, which converts AC power into DC power and is connected to a filter capacitor.

The supporting bus capacitors 8 are connected in parallel to increase the power supply capability of the receiving coil.

Said load 9 is generally a resistive load.

FIGS. 3 to 7 show the position of the receiving coil 5 when the vehicle moving equipment moves from the range of the first transmitting coil 41 to the range of the second transmitting coil 42 .

When the receiving coil 5 is located in the position shown in FIG. 3, the receiving coil 5 is located within the power supply range of the first transmitting coil 41. At this time, the first receiving coil 51, the second receiving coil 52, and the third receiving coil 53 are connected to the circuit, and the first receiving coil 51, the second receiving coil 52, and the third receiving coil 53 are connected to the circuit. One control switch 31 is closed, the second control switch 32 is opened, and the receiving coil 5 is powered by the first transmitting coil 41 .

When the receiving coil 5 is located in the position shown in FIG. 4 , the first receiving coil 51 is located at the junction of the first transmitting coil 41 and the second transmitting coil 42 , and the second receiving coil 52 and the third receiving coil 53 are located at the first transmitting coil 41 . range. At this time, the control switches 31 and 32 are closed, the second receiving coil 52 and the third receiving coil 53 are connected to the circuit, and the first receiving coil 51 is bypassed due to the low induced voltage. At this time, the three receiving coils 51 , 53 and 53 Powered by the first transmit coil 41 .

When the receiving coil 5 is located in the position shown in FIG. 5 , the first receiving coil 51 is located within the range of the second transmitting coil 42 , the second receiving coil 52 is located at the junction of the first transmitting coil 41 and the second transmitting coil 42 , and the third The receiving coil 4 is located within the range of the first transmitting coil 41 . At this time, the first control switch 31 and the second control switch 32 are closed, the first receiving coil 51 and the third receiving coil 53 are connected to the circuit, and the second receiving coil 52 is bypassed due to the low induced voltage. The first receiving coil 51 is powered by the second transmitting coil 42 , and the third receiving coil 53 is powered by the first transmitting coil 41 .

When the receiving coil 5 is located in the position shown in FIG. 6 , the first receiving coil 51 and the second receiving coil 52 are located within the range of the second transmitting coil 42 , and the third receiving coil 53 is located between the first transmitting coil 41 and the second transmitting coil 42 . Junction. At this time, the control switches 31 and 32 are closed, the first receiving coil 51 and the second receiving coil 52 are connected to the circuit, and the third receiving coil 53 is bypassed due to the low induced voltage. The first receiving coil 51 and the second receiving coil 52 are powered by the second transmitting coil 42 .

When the receiving coil 5 is located at the position shown in FIG. 7 and the receiving coil 5 is located within the range of the second transmitting coil 42 , the second control switch 32 is closed, the first control switch 31 is opened, and the first receiving coil 51 and the second receiving coil 51 are closed. The coil 52 and the third receiving coil 53 are connected to the circuit. The first receiving coil 51 , the second receiving coil 52 , and the third receiving coil 53 are powered by the second transmitting coil 42 .

Claims (3)

1. A contactless power supply device for rail transit with multiple receiving coils segmented by a transmitting coil, the contactless power supply device comprises a ground device (11) and a vehicle-mounted mobile device (12); the ground device (11) includes a high A frequency current source (1), a power bus (2), a control switch (3) and a transmitting coil (4); the transmitting coil (4) is laid along the track and is connected to the corresponding control switch (3), and the control switch (3) is connected to the power supply busbar (2); the vehicle-mounted mobile device (12) includes a plurality of receiving coils (5), a receiving coil compensation circuit (6), a high-frequency rectifying device (7), a busbar supporting capacitor (8) and a load ( 9); the receiving coil (5) is connected to the receiving coil compensation circuit (6), the receiving coil compensation circuit (6) is connected to the high-frequency rectifying device (7), and the high-frequency rectifying device (7) is connected to the bus support capacitor (8), A series branch is formed; the output ends of the multiple bus support capacitors (8) are connected in parallel, and then connected to the load (9), It is characterized in that: the transmitting coil (4) is a segmented structure, and each transmitting coil is connected with a high-frequency current source (1); the end of each transmitting coil has an angle α, and the angle α is an acute angle, Satisfy 0<actan(α)≤b/L, where b is the length of the receiving coil along the running direction, and L is the width of the transmitting coil; multiple receiving coils are installed on the bottom of the locomotive and are arranged in sequence along the track direction. The same, the electromagnetic parameters of self-inductance and mutual inductance are the same and independent of each other; the length of each transmitting coil is greater than the sum of the lengths of multiple receiving coils. 2. The contactless power supply device for rail transit according to claim 1, characterized in that the receiving coil (5) moves with the car; when the receiving coil (5) is located in a certain section of the transmitting coil section (4), it is transmitted with this section. The control switch (3) connected to the coil is closed, and electricity is drawn from the power bus (2) to supply power to the load (9); when the receiving coil (5) is in the over-segmented position, the receiving coil (5) is rectified by the high-frequency rectifying device (7) Blocking, no power is supplied to the load (9); when the receiving coil (5) is located in the next section of the transmitting coil (4), the control switch (3) corresponding to the transmitting coil (4) of this section is closed, and continues to the load (9) powered by. 3. The contactless power supply device for rail transit according to claim 1, characterized in that the number of said receiving coils is at least 1 more than the number N of receiving coils when the transmitting coil is not segmented, ensuring that the receiving coil (5) has a N receiving coils are connected to the load.

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