A high-voltage power distribution unit of a new energy vehicle and a relay driving device thereof

Abstract

The application discloses a high-voltage power distribution unit of a new energy automobile and a relay driving device thereof. The device is applied to the high-voltage power distribution unit of the new energy automobile. The fast charging port of the new energy automobile is provided with a first relay and a second relay. The relay driving device comprises a control signal input end, a delay control circuit, a first output end and a second output end. The control signal input end is used for receiving a conduction control signal output by a controller of the high-voltage power distribution unit. The first output end is connected with the control signal input end and the first relay respectively and is used for forwarding the conduction control signal to a signal input end of the first relay in real time. The input end of the delay control circuit is connected with the control signal input end and the output end is connected with the second output end. After the conduction control signal is received by the control signal input end, the delay control circuit forwards the conduction control signal to the second output end after a preset time delay. The second output end is connected with a signal input end of the second relay. That is, the conduction control signal is not output to the first relay and the second relay at the same time but is different by a preset time length. In this way, the driving current can be obviously reduced and the automobile circuit can be prevented from being damaged.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle technology, and more specifically, to a high-voltage power distribution unit for a new energy vehicle and its relay drive device. Background Technology

[0002] High-voltage power distribution units (PDUs) are key components in new energy vehicles, responsible for the distribution and management of electrical energy. Traditional PDUs typically include independent thermal management systems and DC / DC converters. PDUs also control the fast-charging ports of new energy vehicles and manage charging based on relays installed at the fast-charging ports. However, some new energy vehicles, for cost control reasons, only have a relay on the negative terminal of the charging port input, while the positive terminal remains constantly open. This could potentially cause electric shock if a person comes into contact with the positive terminal.

[0003] To prevent electric shock, it is necessary to also configure a corresponding relay at the positive input terminal. However, this requires simultaneously controlling the on / off state of two relays when charging new energy vehicles. The inventors of this application have discovered in practice that controlling two relays to simultaneously turn on or off requires a larger drive current compared to a single relay, and this larger drive current itself can damage the vehicle's electrical circuitry. Summary of the Invention

[0004] In view of this, this application provides a high-voltage power distribution unit for a new energy vehicle and its relay driving device, which is used to control the two relays configured on and off at the fast charging port in a time-sharing manner when the high-voltage power distribution unit controls the charging of the new energy vehicle, so as to reduce the driving current.

[0005] To achieve the above objectives, the following solution is proposed:

[0006] A relay driving device is applied to the high-voltage power distribution unit of a new energy vehicle. The fast charging port of the new energy vehicle is equipped with a first relay and a second relay. The relay driving device includes a control signal input terminal, a delay control circuit, a first output terminal, and a second output terminal, wherein:

[0007] The control signal input terminal is used to receive the conduction control signal output by the controller of the high-voltage power distribution unit;

[0008] The first output terminal is connected to the control signal input terminal and the fast first relay respectively, and is used to forward the conduction control signal to the signal input terminal of the first relay in real time;

[0009] The input terminal of the delay control circuit is connected to the control signal input terminal, and the output terminal is connected to the second output terminal. After receiving the conduction control signal at the control signal input terminal, the circuit forwards the conduction control signal to the second output terminal after a preset delay. The second output terminal is connected to the signal input terminal of the second relay.

[0010] Optionally, the delay control circuit includes a positive input terminal, a negative input terminal, a positive output terminal, a negative output terminal, a voltage divider circuit, a first switching circuit, a reference voltage circuit, an RC circuit, a comparator circuit, and a second switching circuit, wherein:

[0011] The positive terminal of the control signal input terminal is connected to the positive terminal of the input terminal, and the negative terminal is connected to the negative terminal of the input terminal. The positive terminal of the input terminal is connected to the positive terminal of the output terminal through the second switching circuit, and the positive terminal of the output terminal is connected to the positive terminal of the second output terminal.

[0012] The negative terminal of the control signal input terminal is connected to the negative terminal of the output terminal, and the negative terminal of the output terminal is connected to the negative terminal of the second output terminal.

[0013] One end of the voltage divider circuit is connected to the positive terminal of the input terminal, the other end is grounded, and the voltage divider output terminal is connected to the signal input terminal of the first switching circuit.

[0014] One end of the first switching circuit is connected to the positive terminal of the input terminal and the non-inverting input terminal of the comparator circuit, and the other end of the first switching circuit is grounded.

[0015] The reference voltage circuit is connected to the inverting input terminal of the comparator circuit and is used to output a reference voltage to the inverting input terminal.

[0016] The output terminal of the comparator circuit is connected to the control terminal of the second switching circuit, and the non-inverting input terminal is also connected to the positive terminal of the input terminal through the resistor of the RC circuit, which is used to output an enable signal to the control terminal when the output voltage of the RC circuit exceeds the reference voltage;

[0017] The second switching circuit is used to connect the positive terminal of the input terminal to the positive terminal of the output terminal when the turn-on signal is received.

[0018] Optionally, the voltage divider circuit includes a sixth resistor and a seventh resistor, wherein:

[0019] One end of the sixth resistor is connected to the positive terminal of the input terminal, and the other end is connected to one end of the seventh resistor, with the other end of the seventh resistor grounded.

[0020] The other end of the sixth resistor is also connected to the negative terminal of the input terminal and the control terminal of the first switching circuit.

[0021] Optionally, the first switching circuit includes a second transistor, wherein:

[0022] The base of the second transistor is used as the control terminal of the first switching circuit;

[0023] The collector of the second transistor is connected to the non-inverting input of the comparator circuit, and the emitter is grounded.

[0024] Optionally, the reference voltage circuit includes a fourth resistor, a fifth resistor, and a fourth capacitor, wherein:

[0025] One end of the fourth resistor is connected to the positive terminal of the input terminal, one end of the fifth resistor, one end of the fourth capacitor, and the inverting input terminal of the comparator circuit, respectively.

[0026] The other end of the fifth resistor is grounded;

[0027] The other end of the fourth capacitor is grounded.

[0028] Optionally, the RC circuit includes a third resistor and a first capacitor, wherein:

[0029] One end of the third resistor is connected to the positive terminal of the input terminal, and the other end of the third resistor is connected to the non-inverting input terminal of the comparator circuit and one end of the first capacitor, while the other end of the first capacitor is grounded.

[0030] Optionally, the preset duration is 1 second.

[0031] Optionally, the second switching circuit includes a first transistor, a first resistor, a second resistor, and a switching element, wherein:

[0032] The base of the first transistor is connected to the output terminal of the comparator circuit, and its emitter is grounded.

[0033] One end of the first resistor is connected to the positive terminal of the input terminal and one end of the switching element, respectively; the other end of the first resistor is connected to one end of the second resistor and the control terminal of the switching element, respectively.

[0034] The other end of the switching element is connected to the negative terminal of the output terminal;

[0035] The other end of the second resistor is connected to the collector of the first transistor.

[0036] Optionally, the switching element is a MOSFET.

[0037] A high-voltage power distribution unit for a new energy vehicle, wherein the high-voltage power distribution unit is equipped with a relay drive device as described above.

[0038] As can be seen from the above technical solution, this application discloses a high-voltage power distribution unit for a new energy vehicle and its relay driving device. This device is applied to the high-voltage power distribution unit of a new energy vehicle, which has a fast charging port equipped with a first relay and a second relay. The relay driving device includes a control signal input terminal, a delay control circuit, a first output terminal, and a second output terminal. The control signal input terminal receives the conduction control signal output by the controller of the high-voltage power distribution unit. The first output terminal is connected to both the control signal input terminal and the first relay, and is used to forward the conduction control signal to the signal input terminal of the first relay in real time. The input terminal of the delay control circuit is connected to the control signal input terminal, and its output terminal is connected to the second output terminal. After receiving the conduction control signal at the control signal input terminal, it delays for a preset time before forwarding the conduction control signal to the second output terminal. The second output terminal is connected to the signal input terminal of the second relay. That is, the conduction control signal is not output to the first relay and the second relay simultaneously, but with a preset time difference, which significantly reduces the drive current and avoids damage to the vehicle's circuitry. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of a relay driving device according to an embodiment of this application;

[0041] Figure 2 This is a circuit diagram of a delay control circuit according to an embodiment of this application. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0043] Figure 1 This is a schematic diagram of a relay driving device according to an embodiment of this application.

[0044] The relay driving device provided in this embodiment is applied in the high-voltage power distribution unit of a new energy vehicle. The fast charging port of this new energy vehicle is equipped with two relays. The relay driving device is used to control these two relays so that they close or open at staggered times. For ease of distinction, this application describes the two relays as a first relay and a second relay. These two relays are used to respectively turn off the fast charging positive and fast charging negative terminals of the fast charging port. That is, if the first relay is the fast charging positive relay, then the second relay is the fast charging negative relay; conversely, if the first relay is the fast charging negative relay, then the second relay is the fast charging positive relay.

[0045] like Figure 1 As shown, the relay drive device includes a delay control circuit 10, a control signal input terminal 20, a first output terminal 30, and a second output terminal 40. The control signal input terminal is used to connect to the controller 100 of the high-voltage power distribution unit and to receive the conduction control signal output by the controller. Specifically, in this application, the conduction control signal refers to the driving voltage that forms the driving capability, such as +12 volts or +24 volts.

[0046] The control signal input terminal is connected to the first output terminal and is used to directly forward the signal to the first output terminal when a conduction control signal is received. The first output terminal is also connected to the first relay and is used to control the first relay to close or close when a conduction control signal is received.

[0047] The input terminal of the delay control circuit is connected to the control signal input terminal, and its output terminal is connected to the second output terminal. After receiving the conduction control signal from the control signal input terminal, the circuit delays for a preset time before forwarding the conduction control signal to the second output terminal. The second output terminal is connected to the second relay, which closes or closes after receiving the conduction control signal.

[0048] As can be seen from the above technical solution, this embodiment provides a relay driving device applied to the high-voltage power distribution unit of a new energy vehicle. The fast charging port of the new energy vehicle is equipped with a first relay and a second relay. The relay driving device includes a control signal input terminal, a delay control circuit, a first output terminal, and a second output terminal. The control signal input terminal is used to receive the conduction control signal output by the controller of the high-voltage power distribution unit; the first output terminal is connected to both the control signal input terminal and the first relay, and is used to forward the conduction control signal to the signal input terminal of the first relay in real time; the input terminal of the delay control circuit is connected to the control signal input terminal, and the output terminal is connected to the second output terminal, and is used to forward the conduction control signal to the second output terminal after a preset delay after receiving the conduction control signal at the control signal input terminal. The second output terminal is connected to the signal input terminal of the second relay. That is, the conduction control signal is not output to the first relay and the second relay simultaneously, but with a preset time difference, which can significantly reduce the drive current and avoid damage to the vehicle's circuitry.

[0049] The delay control circuit of this application includes an input positive terminal HSD, an input negative terminal LSD, an output positive terminal HSD”, an output negative terminal LSD”, a voltage divider circuit, a first switching circuit, a reference voltage circuit, an RC circuit, a comparator circuit, and a second switching circuit.

[0050] The positive terminal of the control signal input is connected to the positive terminal of the input terminal, and the negative terminal of the negative terminal is connected to the negative terminal. The positive terminal of the input terminal is connected to the positive terminal of the output terminal through the second switching circuit, and the positive terminal of the output terminal is connected to the positive terminal of the second output terminal. The negative terminal of the control signal input is connected to the negative terminal of the output terminal, and the negative terminal of the output terminal is connected to the negative terminal of the second output terminal. One end of the voltage divider circuit is connected to the positive terminal of the input terminal, the other end is grounded, and the voltage divider output terminal is connected to the signal input terminal of the first switching circuit. One end of the first switching circuit is connected to the positive terminal of the input terminal and the non-inverting input terminal of the comparator circuit, and the other end of the first switching circuit is grounded. The reference voltage circuit is connected to the inverting input terminal of the comparator circuit and is used to output a reference voltage to the inverting input terminal. The output terminal of the comparator circuit is connected to the control terminal of the second switching circuit, and the non-inverting input terminal is also connected to the positive terminal of the input terminal through the resistor of the RC circuit, and is used to output an enable signal to the control terminal when the output voltage of the RC circuit exceeds the reference voltage. The second switching circuit is used to connect the positive terminal of the input terminal and the positive terminal of the output terminal when the enable signal is received.

[0051] The voltage divider circuit includes a sixth resistor R6 and a seventh resistor R7, such as... Figure 2 As shown. One end of the sixth resistor is connected to the positive terminal of the input, and the other end is connected to one end of the seventh resistor, the other end of the seventh resistor is grounded; the other end of the sixth resistor is also connected to the negative terminal of the input and the control terminal of the first switching circuit.

[0052] The first switching circuit includes a second transistor Q2, the base of which serves as the control terminal of the first switching circuit; the collector of the second transistor is connected to the non-inverting input terminal of the comparator circuit U1, and the emitter is grounded. The reference voltage circuit includes a fourth resistor R4, a fifth resistor R5, and a fourth capacitor C4. One end of the fourth resistor is connected to the positive input terminal, one end of the fifth resistor, one end of the fourth capacitor, and the inverting input terminal of the comparator circuit; the other end of the fifth resistor and the other end of the fourth capacitor are grounded.

[0053] The RC circuit includes a third resistor R3 and a first capacitor C1. One end of the third resistor is connected to the positive terminal of the input, and the other end of the third resistor is connected to the non-inverting input of the comparator circuit and one end of the first capacitor. The other end of the first capacitor is grounded.

[0054] The second switching circuit includes a first transistor Q1, a first resistor R2, a second resistor R3, and a switching element Q12. The switching element is preferably a MOSFET. The base of the first transistor is connected to the output terminal of the comparator circuit, and its emitter is grounded. One end of the first resistor is connected to the positive terminal of the input and one end of the switching element; the other end of the first resistor is connected to one end of the second resistor and the control terminal of the switching element; the other end of the switching element is connected to the negative terminal of the output; and the other end of the second resistor is connected to the collector of the first transistor.

[0055] The working principle of the above circuit is as follows:

[0056] When HSD is powered on, it is at 12V. HSD powers on 300ms earlier than LSD, but Q2 conducts when LSD is not powered on. The inverting input of comparator U1 immediately reaches 6V, while the non-inverting input is grounded at 0V. At this time, LSD is not powered on, Q2 conducts, meaning the non-inverting input of comparator U1 is grounded at 0V, and the comparator output is low. When LSD conducts, the RC circuit composed of R3 and C1 begins to charge, and soon the non-inverting input of comparator U1 exceeds 6V. Then the comparator outputs a high potential of 5V, MOSFET Q12 conducts, and the 12V from HSD is transmitted to HSD. At this time, the driving voltage of the second relay reaches 12V, and the relay closes. The first relay closes immediately. This achieves the purpose of staggered closing of the two relays. This application can adjust the preset duration by selecting the parameters of the resistors and capacitors in the RC circuit, such as 0.5 seconds, 1 second, etc.

[0057] This embodiment also provides a high-voltage power distribution unit for a new energy vehicle. This high-voltage power distribution unit is equipped with the relay drive device described above. When two relays are installed at the fast charging port of a new energy vehicle, the drive device can stagger the switching on and off of the two relays, thereby reducing the drive current and preventing damage to the vehicle's electrical circuits.

[0058] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0059] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0060] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0061] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A relay drive device applied to a high-voltage power distribution unit of a new energy vehicle, wherein the fast charging port of the new energy vehicle is equipped with a first relay and a second relay, characterized in that, The relay driving device includes a control signal input terminal, a delay control circuit, a first output terminal, and a second output terminal, wherein: The control signal input terminal is used to receive the conduction control signal output by the controller of the high-voltage power distribution unit; The first output terminal is connected to the control signal input terminal and the fast first relay respectively, and is used to forward the conduction control signal to the signal input terminal of the first relay in real time; The input terminal of the delay control circuit is connected to the control signal input terminal, and the output terminal is connected to the second output terminal. After receiving the conduction control signal at the control signal input terminal, the circuit forwards the conduction control signal to the second output terminal after a preset delay. The second output terminal is connected to the signal input terminal of the second relay.

2. The relay driving device as described in claim 1, characterized in that, The delay control circuit includes a positive input terminal, a negative input terminal, a positive output terminal, a negative output terminal, a voltage divider circuit, a first switching circuit, a reference voltage circuit, an RC circuit, a comparator circuit, and a second switching circuit, wherein: The positive terminal of the control signal input terminal is connected to the positive terminal of the input terminal, and the negative terminal is connected to the negative terminal of the input terminal. The positive terminal of the input terminal is connected to the positive terminal of the output terminal through the second switching circuit, and the positive terminal of the output terminal is connected to the positive terminal of the second output terminal. The negative terminal of the control signal input terminal is connected to the negative terminal of the output terminal, and the negative terminal of the output terminal is connected to the negative terminal of the second output terminal. One end of the voltage divider circuit is connected to the positive terminal of the input terminal, the other end is grounded, and the voltage divider output terminal is connected to the signal input terminal of the first switching circuit. One end of the first switching circuit is connected to the positive terminal of the input terminal and the non-inverting input terminal of the comparator circuit, and the other end of the first switching circuit is grounded. The reference voltage circuit is connected to the inverting input terminal of the comparator circuit and is used to output a reference voltage to the inverting input terminal. The output terminal of the comparator circuit is connected to the control terminal of the second switching circuit, and the non-inverting input terminal is also connected to the positive terminal of the input terminal through the resistor of the RC circuit, which is used to output an enable signal to the control terminal when the output voltage of the RC circuit exceeds the reference voltage; The second switching circuit is used to connect the positive terminal of the input terminal to the positive terminal of the output terminal when the turn-on signal is received.

3. The relay driving device as described in claim 2, characterized in that, The voltage divider circuit includes a sixth resistor and a seventh resistor, wherein: One end of the sixth resistor is connected to the positive terminal of the input terminal, and the other end is connected to one end of the seventh resistor, with the other end of the seventh resistor grounded. The other end of the sixth resistor is also connected to the negative terminal of the input terminal and the control terminal of the first switching circuit.

4. The relay driving device as described in claim 2, characterized in that, The first switching circuit includes a second transistor, wherein: The base of the second transistor is used as the control terminal of the first switching circuit; The collector of the second transistor is connected to the non-inverting input of the comparator circuit, and the emitter is grounded.

5. The relay driving device as described in claim 2, characterized in that, The reference voltage circuit includes a fourth resistor, a fifth resistor, and a fourth capacitor, wherein: One end of the fourth resistor is connected to the positive terminal of the input terminal, one end of the fifth resistor, one end of the fourth capacitor, and the inverting input terminal of the comparator circuit, respectively. The other end of the fifth resistor is grounded; The other end of the fourth capacitor is grounded.

6. The relay driving device as described in claim 2, characterized in that, The RC circuit includes a third resistor and a first capacitor, wherein: One end of the third resistor is connected to the positive terminal of the input terminal, and the other end of the third resistor is connected to the non-inverting input terminal of the comparator circuit and one end of the first capacitor, while the other end of the first capacitor is grounded.

7. The relay driving device as described in claim 6, characterized in that, The preset duration is 1 second.

8. The relay driving device as described in claim 2, characterized in that, The second switching circuit includes a first transistor, a first resistor, a second resistor, and a switching element, wherein: The base of the first transistor is connected to the output terminal of the comparator circuit, and its emitter is grounded. One end of the first resistor is connected to the positive terminal of the input terminal and one end of the switching element, respectively; the other end of the first resistor is connected to one end of the second resistor and the control terminal of the switching element, respectively. The other end of the switching element is connected to the negative terminal of the output terminal; The other end of the second resistor is connected to the collector of the first transistor.

9. The relay driving device as described in claim 8, characterized in that, The switching element is a MOSFET.

10. A high-voltage power distribution unit for a new energy vehicle, characterized in that, The high-voltage power distribution unit is equipped with a relay drive device as described in any one of claims 1 to 9.

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