GB2588400A

GB2588400A - Switching circuit and method for constantly supplying power for vehicle

Info

Publication number: GB2588400A
Application number: GB1915224.8A
Authority: GB
Inventors: Boo Foo Wah; Centino Navarro Normel
Original assignee: Vitesco Technologies GmbH
Current assignee: Vitesco Technologies GmbH
Priority date: 2019-10-22
Filing date: 2019-10-22
Publication date: 2021-04-28
Also published as: GB201915224D0; GB2588400A8

Abstract

A switching circuit and a method for constantly supplying power, and particularly for constantly supplying power to a load of a vehicle without damage of the load. The switching circuit for constantly supplying power for a vehicle comprises a load 110; a battery for supplying the power to the load; a detector 130 operable to detect at least one of current and voltage of the battery and determine whether a direction of current flow is normal or reversed; and a switch driver 140 connected between the detector and a plurality of switches 151-154, characterised in that: the switch driver is operable to control at least one of the plurality of switches based on the direction of the current flow, so that the power is constantly supplied to the load without damage of the load. The switches may comprise a first group and a second group, where the switches are enabled/disabled in their groups.

Description

SWITCHING CIRCUIT AND METHOD FOR CONSTANTLY SUPPLYING POWER FOR VEHICLE

TECHNICAL FIELD

The present invention relates to a switching circuit and a method for constantly supplying power, and particularly relates to a switching circuit and a method for constantly supplying power to a load of a vehicle without damage of the load.

BACKGROUND

The following discussion of the background is intended to facilitate an understanding of the present invention only. It may be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge of the person skilled in the art in any jurisdiction as at the priority date of the present invention.

Reverse current means current flowing backwards through a load in a circuit. The reverse current may occur when there is a higher voltage at an output of the load than at an input of the load. However, in general the reverse current is harmful to the circuit, since the reverse current can cause damage to electronic components such as the load. Moreover, the reverse current can damage the circuit and a power supply (for example, a battery). Depending on a path from the output to the input, reverse current spikes can also damage cables and connectors.

In view of the above, systems and methods for protecting the circuit and the battery from the reverse current have been evolved. A diode-integrated circuit has been introduced as a solution. When the reverse current is detected, the diode may cause a forward-voltage drop which increases total power dissipation in the circuit. As another solution, a load switch-integrated circuit has been introduced. When the reverse current is detected, the load switch is open so that the reverse current is blocked.

However, these solutions may cause decreased efficiency in the circuit, since the circuit shuts down when the reverse current occurs, and does not operate until the reverse current is resolved.

In light of the above, there exists a need to provide a solution that meets the mentioned needs at least in part.

SUMMARY

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Furthermore, throughout the specification, unless the context requires otherwise, the word "include" or variations such as "includes" or "including", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

The present invention seeks to provide a switching circuit and a method that addresses the afore-mentioned need at least in part.

The technical solution is provided in the form of a switching circuit and a method for constantly supplying power to a load of a vehicle without damage of the load. The switching circuit comprises a detector operable to determine whether a direction of current flow is normal or reversed by detecting at least one of current and voltage of the battery. A switch driver is operable to receive a signal relating to the direction of the current flow, and control at least one of a plurality of switches based on the direction of the current flow. For example, where the direction of the current flow is normal, the switch driver enables a first group of switches and disables a second group of switches. On the other hand, where the direction of the current flow is reversed, the switch driver enables the second group of switches and disables the first group of switches.

Therefore, the switching circuit in accordance with the present invention can continuously operate without damage of the load, even while the direction of the current flow is reversed.

In accordance with an aspect of the present invention, there is a switching circuit for constantly supplying power for a vehicle comprising: a load; a battery for supplying the power to the load; a detector operable to detect at least one of current and voltage of the battery and determine whether a direction of current flow is normal or reversed; and a switch driver connected between the detector and a plurality of switches, characterised in that: the switch driver is operable to control at least one of the plurality of switches based on the direction of the current flow, so that the power is constantly supplied to the load without damage of the load.

In some embodiments, the plurality of switches comprise a first group of switches and a second group of switches, and where the direction of the current flow is normal, the switch driver is operable to enable the first group of switches and disable the second group of switches; and where the direction of the current flow is reversed, the switch driver is operable to enable the second group of switches and disable the first group of switches.

In some embodiments, the switching circuit further comprises a first battery supply line connecting between a first terminal of the battery and an input of the load, and a second battery supply line connecting a second terminal of the battery and an output of the load, where the direction of the current flow is normal, the first battery supply line is positive and the second battery supply line is negative; and where the direction of the current flow is reversed, the first battery supply line is negative and the second battery supply line is positive.

In some embodiments, the switching circuit further comprises a shunt arranged on the first battery supply line.

In some embodiments, the detector is operable to detect the at least one of current and voltage of the battery through the shunt.

In some embodiments, the switching circuit further comprises a processor, wherein the detector is operable to output a signal relating to the direction of the current flow to at least one of the switch driver and the processor.

In some embodiments, the processor is operable to send information relating to the direction of the current flow to a vehicle system.

In some embodiments, where the direction of the current flow is normal, the processor is operable to report non-error to the vehicle system; and where the direction of the current flow is reversed, the processor is operable to report error to the vehicle system.

In some embodiments, the first group of switches comprises: a first switch connected between the first terminal of the battery and the input of the load; and a fourth switch connected between the second terminal of the battery and the output of the load.

In some embodiments, the second group of switches comprises: a second switch connected between the first terminal of the battery and the output of the load; and a third switch connected between the second terminal of the battery and the input of the load In some embodiments, the detector is further operable to detect at least one of abnormal current and abnormal voltage of the battery.

In some embodiments, where the detector detects the at least one of abnormal current and abnormal voltage of the battery, the detector is operable to output a signal relating 15 to the at least one of abnormal current and abnormal voltage to at least one of the switch driver and a processor.

In some embodiments, where the detector detects the at least one of abnormal current and abnormal voltage of the battery, the switch driver is operable to disable the plurality of switches.

In accordance with another aspect of the present invention, there is a method for constantly supplying power for a vehicle comprising: supplying the power from a battery to a load; detecting at least one of current and voltage of a battery; determining whether a direction of current flow is normal or reversed; and controlling at least one of a plurality of switches based on the direction of the current flow, so that the power is constantly supplied to the load without damage of the load.

In some embodiments, the step of controlling at least one of a plurality of switches based on the direction of the current flow comprises following steps of: enabling a first group of switches and disabling a second group of switches, where the direction of the current flow is normal; and enabling the second group of switches and disabling the first group of switches, where the direction of the current flow is reversed.

Other aspects of the invention will become apparent to those of ordinary skilled in the art upon review of the following description of specific embodiments of the present invention in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a circuit diagram in accordance with an embodiment of the present invention, where a direction of current flow is normal.

Fig. 2 is a circuit diagram in accordance with an embodiment of the present invention, where a direction of current flow is reversed.

Fig. 3 is a circuit diagram in accordance with an embodiment of the present invention, where at least one of current and voltage is abnormal.

Fig. 4 is a flowchart in accordance with an embodiment of the present invention.

Fig. 5 is a flowchart in accordance with another embodiment of the present invention.

Other arrangements of the present invention are possible and, consequently, the accompanying drawings are not to be understood as superseding the generality of the preceding description of the invention.

DETAILED DESCRIPTION OF EMBODIMENT

Figs. 1-2 are circuit diagrams in accordance with an embodiment of the present invention.

As shown in Figs. 1-2, the switching circuit 100 in accordance with an embodiment of the present invention may comprise a load 110, a battery 120, a detector 130, a switch driver 140 and a plurality of switches 150.

Throughout the specification, the switching circuit 100 may also be referred to as an automotive transmission controller unit (also referred to as "TCU").

The load 110 is an electrical component or portion of the switching circuit 100 that may consume electric power. The load 110 may include, but not be limited to, a motor, a solenoid, and so on. It may be appreciated that the switching circuit 100 may comprise one or more loads 110. The load 110 comprises an input 111 and an output 112.

The battery 120 (not shown) is a source supplying power to the switching circuit 100, in particular the load 110. The battery 120 comprises a first terminal and a second terminal. It may be appreciated that the first terminal and the second terminal of the battery 120 have different polarity.

For example, where the direction of the current flow is normal (i.e. in a normal operation) as shown in Fig. 1, the first terminal of the battery 120 provides a voltage, and the second terminal of the battery 120 is connected to a ground. In the normal operation, the first terminal may be a positive terminal and the second terminal may be a negative terminal.

On the other hand, where the direction of the current flow is reversed (i.e. in a reversed operation) as shown in Fig. 2, the first terminal of the battery 120 is connected to the ground, and the second terminal of the battery 120 provides the voltage. In the reversed operation, the first terminal may be the negative terminal and the second terminal may be the positive terminal.

The switching circuit 100 may further comprise a first battery supply line 121 connecting between the first terminal of the battery 120 and the input 111 of the load 110. The switching circuit 100 may further comprise a second battery supply line 122 connecting between the second terminal of the battery 120 and the output 112 of the load 111.

As shown in Fig. 1, in the normal operation, the first battery supply line 121 is positive (as shown in "+ LINE") and the second battery supply line 122 is negative (as shown in "-LINE"). On the other hand, as shown in Fig. 2, in the reversed operation, the first battery supply line 121 is negative (as shown in "-LINE") and the second battery supply line 122 is positive (as shown in "+ LINE").

The detector 130 is also referred to as current/voltage detector 130. The detector 130 is operable to detect at least one of current and voltage of the battery 120. In some 5 embodiments, the detector 130 may detect current or voltage of the battery 120. In some other embodiments, the detector 130 may detect both current and voltage of the battery 120. Based on the detection, the detector 130 is operable to determine whether a direction of current flow is normal or reversed. The detector 130 is further operable to output a signal relating to the direction of the current flow to at least one of 10 the switch driver 140 (via path A as shown in Figs. 1 and 2) and a processor 160 to be described below (via path B as shown in Figs. 1 and 2).

In some embodiments, the switching circuit 100 further comprises a shunt 170. The shunt 170 is a device operable to create a low-resistance path for current so that the current to be measured can flow through the shunt 170. The shunt 170 may be arranged on the first battery supply line 121. In some embodiments, the shunt 170 may be arranged near the first terminal of the battery 120, as shown in Figs. 1 and 2.

The plurality of switches 150 comprise a first group of switches and a second group of switches. The first group of switches comprises a first switch 151 connected between the first terminal of the battery 120 and the input 111 of the load 110, and a fourth switch 154 connected between the second terminal of the battery 120 and the output 112 of the load 110. The second group of switches comprises a second switch 152 connected between the first terminal of the battery 120 and the output 112 of the load 110; and a third switch 153 connected between the second terminal of the battery 120 and the input 111 of the load 110.

Although not shown, in some other embodiments, it may be appreciated that the plurality of switches 150 may further comprise additional switches which do not fall within the first group of switches and the second group of switches.

The switch driver 140 is an electrical component capable of controlling at least one of the plurality of switches 150. The switch driver 140 is connected between the detector 130 and the plurality of switches 150. The switch driver 140 is operable to receive the signal relating to the direction of the current flow. In some embodiments, the switch driver 140 may receive the signal from the detector 130 (via path A as shown in Figs. 1 and 2). In some other embodiments, the switch driver 140 may receive the signal from the processor 160 (via path D as shown in Figs. 1 and 2).

The switch driver 140 controls at least one of the plurality of switches 150 based on the received signal relating to the direction of the current flow which is received from the detector 130 and/or the processor 160, so that the power is constantly supplied to the load 110 without damage of the load 110. In some other embodiments, the switch driver 140 controls at least one of the plurality of switches 150 based on a control signal received from the processor 160 to be described below.

As shown in Fig. 1, in the normal operation, the switch driver 140 is operable to enable the first group of switches (i.e. the first switch 151 and the fourth switch 154, via path Cl and 04 as shown in Fig. 1) and disable the second group of switches (i.e. the second switch 152 and the third switch 153, via path 02 and C3 as shown in Fig. 1).

On the other hand, as shown in Fig. 2, in the reversed operation, the switch driver 140 is operable to enable the second group of switches (i.e. the second switch 152 and the third switch 153, via path C2 and C3 as shown in Fig. 2) and disable the first group of switches (i.e. the first switch 151 and the fourth switch 154, via path Cl and C4 as shown in Fig. 2).

In this regard, as shown in Fig. 1, in the normal operation, the first terminal of the battery 120 provides a voltage and is a positive terminal, and the second terminal of the battery is connected to a ground and is a negative terminal. The switch driver 140 is operable to enable the first switch 151 and the fourth switch 154 and disable the second switch 152 and the third switch 153. As such, the first switch 151 and the fourth switch 154 are closed, and the second switch 152 and the third switch 153 are open.

Therefore, the first terminal which is the positive terminal is connected to the input 111 of the load 110, and the output 112 of the load 110 is connected to the second terminal which is the negative terminal. Accordingly, the current can flow from the positive terminal to the negative terminal through the input 111 of the load 110 and subsequently the output 112 of the load 110.

On the other hand, as shown in Fig. 2, in the reversed operation, the first terminal of the battery 120 is connected to the ground and is the negative terminal, and the second terminal of the battery 120 provides the voltage and is the positive terminal. The switch driver 140 is operable to enable the second switch 152 and the third switch 153 and disable the first switch 151 and the fourth switch 154. As such, the second switch 152 and the third switch 153 are open, and the first switch 151 and the fourth switch 154 are closed.

Therefore, the second terminal which is the positive terminal is connected to the input 111 of the load 110, and the output 112 of the load 110 is connected to the first terminal which is the negative terminal. Accordingly, the current can flow from the positive terminal to the negative terminal through the input 111 of the load 110 and subsequently the output 112 of the load 110, even during the reversed operation.

The switching circuit 100 may further comprise the processor 160. The processor 160 is operable to communicate with switch driver 140 and/or detector 130. The processor 160 is further operable to communicate with a vehicle system 180. In some embodiments, the processor 160 may include, but not be limited to, a micro-controller which can control the motor of the vehicle. In some embodiments, the vehicle system 180 may include, but not be limited to, an ECU of the vehicle.

As described above, the processor 160 is operable to receive the signal relating to the direction of the current flow from the detector 130. In some embodiments, the processor 160 is operable to forward the signal to the switch driver 140 so that the switch driver 140 can control at least one of the plurality of switches 150 based on the signal. In some other embodiments, the processor 160 is operable to receive the signal relating to the direction of the current flow and convert the signal into the control signal, and then send the control signal to the switch driver 140 so that the switch driver 140 can control the at least one of the plurality of switches 150 based on the control signal.

The processor 160 is further operable to send information relating to the direction of the current flow to the vehicle system 180. More specifically, the processor 160 is 30 operable to generate the information as to whether an error has occurred in the switching circuit 100, and to send the information to the vehicle system 180. For example, if the processor 160 receives the signal relating to the reversed operation, the processor 160 may report error to the vehicle system 180. If the processor 160 receives the signal relating to the normal operation, the processor 160 may report non-error to the vehicle system 180.

In some embodiments, the processor 160 may report the error to the vehicle system 180 in the reversed operation, and not report the non-error to the vehicle system 180 in the normal operation.

As described above, the switching circuit 100 is operable to detect the direction of the current flow and to control the switches 150 to protect the load 110 from the reversed current. In addition, the switching circuit 100 can operate even while the direction of the current flow is reversed, by controlling the switches 150. In this regard, there is no need for the user to await until the reversed current is converted into the normal current, and thereby the efficiency of the switching circuit 150 can be improved.

Fig 3 is a circuit diagram in accordance with an embodiment of the present invention, where at least one of current and voltage is abnormal.

As shown in Fig. 3, the detector 130 is further operable to detect at least one of abnormal current and abnormal voltage of the battery 120. In some embodiments, the detector 130 may detect abnormal current or abnormal voltage of the battery 120. In some other embodiments, the detector 130 may detect both abnormal current and abnormal voltage of the battery 120.

The abnormal current may include, but not be limited to, overcurrent and/or undercurrent which can damage the switching circuit 100 and/or the battery 120. The abnormal voltage may include, but not be limited to, overvoltage and/or undervoltage 25 which can damage the switching circuit 100 and/or the battery 120.

Based on the detection, the detector 130 is operable to determine whether a fault operation of the battery 120 occurs. The detector 130 is further operable to output a fault signal relating to the at least one of abnormal current and abnormal voltage to at least one of the switch driver 140 (via path A as shown in Fig. 3) and the processor 160 (via path B as shown in Fig. 3).

The processor 160 is operable to receive the fault signal from the detector 130 (via path B as shown in Fig. 3). In some embodiments, the processor 160 is operable to forward the fault signal to the switch driver 140 (via path D as shown in Fig. 3) so that the switch driver 140 can control at least one of the plurality of switches 150 based on the fault signal. In some other embodiments, the processor 160 is operable to receive the fault signal and convert the fault signal into a control signal, and then send the control signal to the switch driver 140 (via path D as shown in Fig. 3) so that the switch driver 140 can control the at least one of the plurality of switches 150 based on the control signal.

The switch driver 140 is operable to receive the fault signal. In some embodiments, the switch driver 140 receives the fault signal from the detector 130. In some other embodiments, the switch driver 140 receives the signal from the processor 160.

As shown in Fig. 3, the switch driver 140 may control the plurality of switches 150 to prevent damage to the battery 120. The switch driver 140 controls at least one of the plurality of switches 150 based on the fault signal received from the detector 130 and/or the processor 160 to prevent damage to the battery 120 which can be caused by the abnormal current and/or abnormal voltage. In some other embodiments, the switch driver 140 controls at least one of the plurality of switches 150 based on the control signal received from the processor 160.

Based on the received fault signal or control signal, the switch driver 140 is operable to disable the plurality of switches 150 including the first group of switches (i.e. the first switch 151 and the fourth switch 154, via path Cl and C4 as shown in Fig. 3) and the second group of switches (i.e. the second switch 152 and the third switch 153, via path 02 and 03 as shown in Fig. 3). As such, the switching circuit 100 may be open, and thereby the current may not flow. In this regard, the switching circuit 100 including the battery 120 can be protected from the abnormal current and/or abnormal voltage.

As shown in Fig. 4, the battery 120 supplies the power to the load 110 (S110). More specifically, the battery 120 supplies the power to the load 110 via the first battery supply line 121 and the second battery supply line 122.

The detector 130 is operable to detect at least one of current and voltage of the battery 120 (S120). The detector 130 detects the at least one of current and voltage of the battery 120 using the shunt 170. In some embodiments, the detector 130 can detect the at least one of current and voltage of the battery 120 on a predetermined period. In some other embodiments, the detector 130 can detect the at least one of current and voltage of the battery 120 irregularly.

The detector 130 is operable to determine whether the direction of the current flow is normal or reversed (S130). Specifically, the detector 130 can determine whether the direction of the current flow is normal or reversed, based on the detected current and/or voltage of the battery 120.

Next, the switch driver 140 is operable to control at least one of a plurality of switches 150 based on the direction of the current flow, so that the power is constantly supplied to the load 110 without damage of the load 110 (S140). As the at least one of the plurality of switches 150 is controlled, the flow of the current in the switching circuit 110 can be changed, so that the power is constantly supplied to the load 110 without damage of the load 110 even during the reversed operation.

After the at least one of the plurality of switches 150 is controlled or while the at least one of the plurality of switches 150 is controlled, the detector 130 can detect the at least one of current and voltage of the battery 120 (S120) to determine whether the direction of the current flow is normal or reversed (S130). As mentioned above, in some embodiments, the detector 130 can detect the at least one of current and voltage of the battery 120 on a predetermined period. In some other embodiments, the detector 130 can detect the at least one of current and voltage of the battery 120 irregularly.

As shown in Fig. 5, the battery 120 supplies the power to the load 110 (5110). The detector 130 is operable to detect at least one of current and voltage of the battery 120 (3120), and to determine whether the direction of the current flow is normal or reversed (3130) based on the detected current and/or voltage of the battery 120.

If the direction of the current flow is normal, the switch driver 140 is operable to enable the first group of switches and disable the second group of switches. On the other hand, if the direction of the current flow is reversed, the switch driver 140 is operable to enable the second group of switches and disable the first group of the switches.

After the first and second group of switches are controlled or while the first and second group of switches are controlled, the detector 130 can detect the at least one of current and voltage of the battery 120 (3120) to determine whether the direction of the current flow is normal or reversed (3130).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims. However, this is merely an exemplarily embodiment, and those skilled in the art will recognize that various modifications and equivalents are possible in light of the above embodiments.

LIST OF REFERENCE SIGNS 110: Load 100: Switching circuit 112: Output 111: Input 121 First battery supply line 120: Battery 130: Detector 122: Second battery supply line 150: Switches 140: Switch driver 152: Second switch 151: First switch 153: Third switch 154: Fourth switch 160: Processor 170: Shunt 180: Vehicle system

Claims

CLAIMS1. A switching circuit for constantly supplying power for a vehicle comprising: a load; a battery for supplying the power to the load; a detector operable to detect at least one of current and voltage of the battery and determine whether a direction of current flow is normal or reversed; and a switch driver connected between the detector and a plurality of switches, characterised in that: the switch driver is operable to control at least one of the plurality of switches based on the direction of the current flow, so that the power is constantly supplied to the load without damage of the load.
2. The switching circuit according to claim 1, wherein the plurality of switches comprise a first group of switches and a second group of switches, and where the direction of the current flow is normal, the switch driver is operable to enable the first group of switches and disable the second group of switches; and where the direction of the current flow is reversed, the switch driver is operable to enable the second group of switches and disable the first group of switches.
3. The switching circuit according to claim 2 further comprising a first battery supply line connecting between a first terminal of the battery and an input of the load, and a second battery supply line connecting a second terminal of the battery and an output of the load, where the direction of the current flow is normal, the first battery supply line is positive and the second battery supply line is negative; and where the direction of the current flow is reversed, the first battery supply line is negative and the second battery supply line is positive.
4. The switching circuit according to claim 3 further comprising a shunt arranged on the first battery supply line.
5. The switching circuit according to claim 4, wherein the detector is operable to detect the at least one of current and voltage of the battery through the shunt.
6. The switching circuit according to claim 5 further comprising a processor, wherein the detector is operable to output a signal relating to the direction of the current flow to at least one of the switch driver and the processor.
7. The switching circuit according to claim 6, wherein the processor is operable to send information relating to the direction of the current flow to a vehicle system.
8. The switching circuit according to claim 7, wherein where the direction of the current flow is normal, the processor is operable to report non-error to the vehicle system; and where the direction of the current flow is reversed, the processor is operable to report error to the vehicle system.
9. The switching circuit according to claim 3, wherein the first group of switches comprises: a first switch connected between the first terminal of the battery and the input of the load: and a fourth switch connected between the second terminal of the battery and the output of the load
10. The switching circuit according to claim 9, wherein the second group of switches comprises: a second switch connected between the first terminal of the battery and the output of the load, and a third switch connected between the second terminal of the battery and the input of the load.
11. The switching circuit according to claim 5, wherein the detector is further operable to detect at least one of abnormal current and abnormal voltage of the 15 battery.
12. The switching circuit according to claim 11, wherein where the detector detects the at least one of abnormal current and abnormal voltage of the battery, the detector is operable to output a signal relating to the at least one of abnormal current and 20 abnormal voltage to at least one of the switch driver and a processor.
13. The switching circuit according to claim 12, wherein where the detector detects the at least one of abnormal current and abnormal voltage of the battery, the switch driver is operable to disable the plurality of switches.
14. A method for constantly supplying power for a vehicle comprising: supplying the power from a battery to a load; detecting at least one of current and voltage of the battery; determining whether a direction of current flow is normal or reversed. and controlling at least one of a plurality of switches based on the direction of the current flow, so that the power is constantly supplied to the load without damage of the load.
15. The method according to claim 14, wherein the step of controlling at least one of a plurality of switches based on the direction of the current flow comprises following steps of: enabling a first group of switches and disabling a second group of switches, where the direction of the current flow is normal; and enabling the second group of switches and disabling the first group of switches, 15 where the direction of the current flow is reversed.