Power supply equipment

Abstract

This technology provides a way to easily reduce the number of switches in a configuration that supplies power to multiple loads. [Solution] The power supply device 10 supplies power from the power supply unit 2 to multiple loads 3. The power supply device 10 comprises multiple conductive paths 11 connected to the multiple loads 3, a connection part (first connection part 12), a circuit part 13, and a control unit 16. The connection part connects the ends on the power supply unit 2 side of each conductive path 11. The circuit part 13 has a switch 31. The control unit 16 controls the switch 31. The circuit part 13 is provided between the connection part and the power supply unit 2 and is connected to the connection part. The control unit 16 sets a duty cycle ratio, which is the ratio of the on time to the switching period, and adjusts the current supplied to the connection part by duty-controlling the switch 31 with the set duty cycle ratio. Furthermore, there are one or more circuit parts 13, and fewer than the number of conductive paths 11.

Description

Technical Field

[0001] The present disclosure relates to a power supply device.

Background Art

[0002] Patent Document 1 discloses a power supply system that supplies power from a power source to a plurality of loads. This power supply system includes a fuse having one end electrically connected to a power source, and a plurality of semiconductor switches each electrically connected between the other end of the fuse and the plurality of loads. This power supply system supplies power to the plurality of loads by PWM controlling the plurality of semiconductor switches.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technology of Patent Document 1, it is necessary to increase the number of switches as the number of loads increases.

[0005] An object of the present disclosure is to provide a technology that facilitates reducing the number of switches in a configuration for supplying power to a plurality of loads.

Means for Solving the Problems

[0006] The power supply device of the present disclosure is a power supply device that supplies power based on a power supply unit to a plurality of loads, and includes a plurality of conductive paths connected to the plurality of loads, a connection unit that connects ends on the power supply unit side in each of the conductive paths, a circuit unit having a switch, and a control unit that controls the switch. The circuit section is provided between the connection section and the power supply section and is connected to the connection section. The control unit sets a duty cycle, which is the ratio of the on-time to the switching period, and controls the switch according to the set duty cycle to adjust the current supplied to the connection section. Furthermore, the number of circuit sections is one or more, and fewer than the number of conductive paths. [Effects of the Invention]

[0007] The technology described herein facilitates a reduction in the number of switches in configurations that supply power to multiple loads. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram of a vehicle equipped with a power supply device according to the first embodiment. [Modes for carrying out the invention]

[0009] The embodiments of this disclosure are listed and illustrated below.

[0010] [1] A power supply device that supplies power based on a power supply unit to multiple loads, Multiple conductive paths connected to multiple loads, A connecting portion that connects the ends on the power supply side of each of the aforementioned conductive paths, A circuit section having a switch, The system comprises a control unit that controls the switch, The circuit section is provided between the connection section and the power supply section and is connected to the connection section. The control unit sets a duty cycle, which is the ratio of the on-time to the switching period, and controls the switch according to the set duty cycle to adjust the current supplied to the connection section. Furthermore, the number of circuit sections is one or more, and fewer than the number of conductive paths. Power supply device.

[0011] The above power supply device can adjust the current supplied to the connection part in the circuit part and supply it to a plurality of loads. Moreover, since the number of circuit parts is less than the number of conductive paths connected to each load, the number of switches in the circuit part can also be made less than the number of conductive paths. Therefore, the above power supply device can easily reduce the number of switches in a configuration for supplying power to a plurality of loads.

[0012] 〔2〕The control unit selects and sets any one of the duty ratios of a plurality of stages. The power supply device according to 〔1〕.

[0013] The above power supply device can set the duty ratio step by step.

[0014] 〔3〕The number of steps of the duty ratio is the same as the number of the conductive paths. The power supply device according to 〔2〕.

[0015] The above power supply device can set the duty ratio in the same number of steps as the number of loads.

[0016] 〔4〕The duty ratio of the first stage is a value adjusted so that a current of a reference value flows through the connection part, The duty ratio of the Nth stage after the second stage is a value adjusted so that a current obtained by multiplying the reference value by N flows through the connection part. The power supply device according to 〔3〕.

[0017] The above power supply device can increase the total current value supplied to a plurality of loads in proportion to the steps of the duty ratio.

[0018] 〔5〕A plurality of the above circuit parts are provided. The control unit performs duty control by synchronizing the on-off timing of each switch included in each of the circuit parts. The power supply device according to any one of 〔1〕 to 〔4〕.

[0019] Because the on / off timing of each switch in the above power supply device is synchronized, it is easier to prevent current from concentrating in certain parts of the circuit.

[0020] [6] A detection unit that detects the voltage value of any of the multiple circuit sections, or the value of the current flowing through any of the multiple circuit sections, The control unit determines whether or not an overcurrent state exists based on the detected value of the detection unit, and if it determines that an overcurrent state exists, it switches all of the switches to the off state. The power supply device described in [5].

[0021] The above-mentioned power supply device can easily reduce the number of detection units because the detection unit used to determine the overcurrent condition can be provided in any of the multiple circuit sections.

[0022] [7] A power supply device for a vehicle, The control unit sets the duty cycle based on at least one of the vehicle's outside temperature and a switching operation performed by the control unit. A power supply device as described in any of [1] to [6].

[0023] The above-mentioned power supply device can set the duty cycle in accordance with at least one of the vehicle's outside temperature and the switching operation performed by the control unit.

[0024] [8] All of the aforementioned switches are of the same model number. A power supply device as described in any of [1] to [7].

[0025] The above power supply device makes it easier to equalize the performance of the switches in each circuit section.

[0026] [9] The multiple loads are one of the following: heater, motor, lamp, and ECU. A power supply device as described in any of [1] through [8].

[0027] The above-mentioned power supply device can adjust the current supplied to multiple identical loads.

[0028] <First Embodiment> Figure 1 shows a vehicle 1 equipped with a power supply device 10. The vehicle 1 comprises a power supply unit 2 and a plurality of loads 3 (3 in this embodiment). The vehicle 1 supplies power from the power supply unit 2 to the plurality of loads 3 via the power supply device 10.

[0029] Power supply unit 2 is, for example, a battery. The battery is, for example, a lead-acid battery or a lithium-ion battery.

[0030] In this embodiment, all of the multiple loads 3 are heaters. A heater is composed of, for example, a PTC thermistor. Note that loads 3 may be other than heaters, such as a motor, lamp, or ECU (Electronic Control Unit). The multiple loads 3 may be an integrated device or separate devices.

[0031] The power supply device 10 is installed between the power supply unit 2 and the multiple loads 3. The power supply device 10 supplies power based on the power supply unit 2 to the multiple loads 3. The power supply device 10 comprises multiple conductive paths 11, a first connection part 12, a circuit part 13, a second connection part 14, a detection part 15, and a control unit 16.

[0032] Multiple conductive paths 11 are connected to multiple loads 3. The number of conductive paths 11 is the same as the number of loads 3 (3 in this embodiment). Each conductive path 11 is connected to a different load 3. Multiple conductive paths 11 are provided between the power supply unit and the multiple loads 3. Multiple conductive paths 11 are provided in parallel with each other. An output terminal 20 is provided at the end of each conductive path 11 opposite to the power supply unit 2. A load 3 is connected to the output terminal 20.

[0033] The first connection section 12 is an example of a "connection section". The first connection section 12 connects the ends of each conductive path 11 on the power supply unit 2 side. Each conductive path 11 is short-circuited to each other via the first connection section 12. Each load 3 is short-circuited to the first connection section 12 by being connected to the conductive path 11.

[0034] The circuit unit 13 is provided between the first connection unit 12 and the power supply unit 2. The circuit unit 13 is connected to the first connection unit 12. The circuit unit 13 has a power path 30 and a switch 31. The power path 30 is provided between the first connection unit 12 and the power supply unit 2. The power path 30 is connected to the first connection unit 12. The switch 31 is provided on the power path 30. When the switch 31 is in the ON state, current from the power supply unit 2 is supplied to the first connection unit 12 via the switch 31. When the switch 31 is in the OFF state, the flow of current to the first connection unit 12 via the switch 31 is interrupted. In this embodiment, the switch 31 is configured to include a semiconductor switch. In this embodiment, the semiconductor switch is a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor). In this embodiment, the configuration including the semiconductor switch consists only of the semiconductor switch, but it may also be a configuration that integrates protection circuits, etc. (for example, an IPD (Intelligent Power Device)).

[0035] The number of circuit sections 13 is one or more, and fewer than the number of conductive paths 11. In this embodiment, the number of circuit sections 13 is two. The multiple circuit sections 13 are arranged in parallel between the power supply unit 2 and the first connection unit 12. Each circuit section 13 (more specifically, power path 30) is connected to the first connection unit 12 and short-circuits each other via the first connection unit 12. The second connection unit 14 connects the ends of the multiple circuit sections 13 (more specifically, power paths 30) on the power supply unit 2 side. When the switch 31 is in the ON state, the current from the power supply unit 2 flows into the circuit sections 13 (more specifically, power paths 30) via the second connection unit 14 and is supplied to the first connection unit 12. As a result, the current from the power supply unit 2 is supplied to the multiple loads 3 via the first connection unit 12. All of the switches 31 are of the same model number.

[0036] Circuit section 13 includes circuit sections 13A and 13B. Circuit section 13A has a power line 30A and a switch 31A. Circuit section 13B has a power line 30B and a switch 31B.

[0037] The detection unit 15 is, for example, a known voltage detection circuit. The detection unit 15 detects the voltage value of the circuit unit 13A. More specifically, the detection unit 15 detects the voltage in the power line 30A on the first connection unit 12 side of the switch 31A. The detection unit 15 outputs a signal that allows the detection value to be identified.

[0038] The control unit 16 is, for example, a control circuit such as an integrated circuit. The control unit 16 controls the switch 31. The control unit 16 sets the duty cycle, which is the ratio of the on time to the switching period. The control unit 16 adjusts the current supplied to the first connection unit 12 by duty-controlling the switch 31 with the set duty cycle. In this embodiment, the duty cycle control is PWM (Pulse Width Modulation) control, but it may also be duty cycle control with a variable period (for example, PFM (Pulse Frequency Modulation) control).

[0039] The control unit 16 selects and sets one of several duty cycle levels. The number of duty cycle levels is the same as the number of conductive paths 11 and the number of loads 3. In other words, in this embodiment, the number of duty cycle levels is 3.

[0040] The duty cycle in the first stage is a value that adjusts the current so that a reference value current flows through the first connection 12. The duty cycles in the second and subsequent Nth stages are values ​​that adjust the current so that a current N times the reference value flows through the first connection 12. For example, if the reference value is 24A, the duty cycle in the first stage is a value that adjusts the current so that 24A flows through the first connection 12. The duty cycle in the second stage is a value that adjusts the current so that a current twice 24A (48A) flows through the first connection 12. The duty cycle in the third stage is a value that adjusts the current so that a current three times 24A (72A) flows through the first connection 12. "Current N times the reference value" includes not only currents that are strictly N times the reference value, but also currents that are effectively N times the reference value. "A current that is effectively N times the reference value" means "a current that is greater than or equal to (N-0.1) times the reference value, and less than or equal to (N+0.1) times the reference value." For example, "a current that is effectively twice the reference value" means "a current that is greater than or equal to 1.9 times the reference value, and less than or equal to 2.1 times the reference value." N is an integer greater than or equal to 2. The duty cycle is a value greater than 0% and less than or equal to 100%.

[0041] The control unit 16 synchronizes the on / off timing of each switch 31 in each circuit unit 13 and performs duty cycle control. The power supply device 10 has a common line 33 and a plurality of branch lines 34. Each branch line 34 branches off from the common line 33 and is connected to the input section (gate) of each switch 31. The signal applied to the common line 33 is applied to the input section (gate) of each switch 31 via each branch line 34. The control unit 16 synchronizes the on / off timing of each switch 31 in each circuit unit 13 and performs duty cycle control by applying a control signal to the common line 33.

[0042] The control unit 16 determines whether or not an overcurrent condition exists based on the detected value of the detection unit 15. The control unit 16 makes this determination based, for example, on the detected value of the detection unit 15 and a threshold value. More specifically, the control unit 16 determines that an overcurrent condition exists if the detected value of the detection unit 15 is less than or equal to the threshold value when the switch 31A is ON. The control unit 16 determines that an overcurrent condition does not exist if the detected value of the detection unit 15 is not less than or equal to the threshold value when the switch 31A is ON. If the control unit 16 determines that an overcurrent condition exists, it switches all switches 31 to the OFF state.

[0043] The control unit 16 sets the duty cycle based on at least one of the ambient temperature of the vehicle 1 and a switching operation performed by an operating unit 41 provided on the vehicle 1. The control unit 16 may acquire the ambient temperature of the vehicle 1 based on a signal output by a temperature detection unit 40 provided on the vehicle 1. The temperature detection unit 40 is, for example, a known temperature sensor. It detects the ambient temperature of the vehicle 1 and outputs a signal that allows for the identification of the detected value. The control unit 16 may acquire the signal output from the temperature detection unit 40 directly or through another device. The operating unit 41 is, for example, an operating member for adjusting the temperature of a heater (load 3). The set duty cycle is switched when the position of the operating member is switched.

[0044] For example, the control unit 16 sets a higher duty cycle when the ambient temperature of vehicle 1 is low. This increases the current supplied to load 3 when the ambient temperature of vehicle 1 is low, causing the heater (load 3) to heat up. Conversely, the control unit 16 sets a lower duty cycle when the ambient temperature of vehicle 1 is high. This reduces the current supplied to load 3 when the ambient temperature of vehicle 1 is high, causing the heater (load 3) to heat down.

[0045] For example, if the control unit 16 is instructed to increase the heater temperature through a switching operation, it sets a higher duty cycle. This increases the current supplied to load 3, raising the temperature of the heater (load 3). Conversely, if the control unit 16 is instructed to decrease the heater temperature through a switching operation, it sets a lower duty cycle. This reduces the current supplied to load 3, lowering the temperature of the heater (load 3).

[0046] The following description concerns the operation of the power supply device 10. The control unit 16 sets the duty cycle when the start condition is met. The start condition may be that the start switch of the vehicle 1 is switched to the ON state, that a start operation is performed by the user, or other conditions. The control unit 16 sets the duty cycle based, for example, on the outside temperature of the vehicle 1 or the position of the operating member when the start condition is met. Then, the control unit 16 controls the switch 31 duty cycle according to the set duty cycle. The control unit 16 controls the duty cycle of all switches 31 in synchronization with the ON / OFF timing of the switches 31.

[0047] The control unit 16 determines whether or not an overcurrent condition exists during duty cycle control. If the control unit 16 determines that an overcurrent condition exists, it stops the duty cycle control and switches all switches 31 to the off state.

[0048] Furthermore, the control unit 16 determines whether or not a termination condition has been met during duty cycle control. The termination condition may be that the start switch of vehicle 1 has been switched to the off state, that a termination operation has been performed by the user, or any other condition. If the termination condition is met, the control unit 16 terminates the duty cycle control and switches all switches 31 to the off state.

[0049] The following explanation concerns the effects of the power supply device 10. The power supply device 10 can supply power to multiple loads 3 by adjusting the current supplied to the first connection part 12 in the circuit part 13. Moreover, since the number of circuit parts 13 is less than the number of conductive paths 11 connected to each load 3, the number of switches 31 in the circuit parts 13 can also be less than the number of conductive paths 11. Therefore, the power supply device 10 can easily reduce the number of switches 31 in a configuration that supplies power to multiple loads 3.

[0050] The power supply device 10 can set the duty cycle in steps. The power supply device 10 can set the duty cycle in the same number of steps as the number of loads 3. The power supply device 10 can increase the total current value supplied to the multiple loads 3 in proportion to the steps of the duty cycle.

[0051] Since the on / off timing of each switch 31 is synchronized in the power supply device 10, it is easier to prevent current from concentrating in some circuit sections 13.

[0052] The power supply device 10 only needs to have a detection unit 15 used to determine an overcurrent condition in circuit section 13A among the multiple circuit sections 13, making it easy to reduce the number of detection units 15.

[0053] The power supply device 10 can set the duty cycle in accordance with at least one of the outside temperature of the vehicle 1 and the switching operation performed by the control unit 41.

[0054] The power supply device 10 makes it easier to equalize the performance of the switches 31 in each circuit section 13.

[0055] The power supply device 10 can adjust the current supplied to multiple identical loads 3.

[0056] <Other Embodiments> This disclosure is not limited to the embodiments described above and in the drawings. For example, any combination of the features of the embodiments described above or below is possible as long as it does not contradict each other. Furthermore, any feature of the embodiments described above or below may be omitted unless explicitly stated as essential. In addition, the embodiments described above may be modified as follows.

[0057] The number of duty cycle stages does not have to be the same as the number of conductive paths, nor does it have to be the same as the number of loads.

[0058] The on / off timing of each switch does not need to be synchronized.

[0059] In the embodiments described above, the detection unit was configured to detect the voltage value of the circuit, but it may also be configured to detect the current flowing through the circuit. In this case, the detection unit may be, for example, a known current sensor. The control unit may determine that an overcurrent state exists when the detected value (the value of the current flowing through the circuit) exceeds the threshold current.

[0060] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is not limited to the embodiments disclosed herein, and is intended to include all modifications within the scope set forth in the claims or equivalents thereof. [Explanation of Symbols]

[0061] 1…Vehicle 2…Power supply section 3…Load 10…Power supply device 11...Conductive path 12...First connection part (connection part) 13...Circuit section 13A...Circuit section 13B...Circuit section 14…Second connection section 15...Detection unit 16…Control Unit 20…Output terminal 30…Power line 30A…Power line 30B…Power line 31…Switch 31A…Switch 31B... Switch 33…Common Line 34... Branch line 40...Temperature detection unit 41...Operation unit

Claims

1. A power supply device that supplies power based on a power supply unit to multiple loads, Multiple conductive paths connected to multiple loads, A connecting portion that connects the ends on the power supply side of each of the aforementioned conductive paths, A circuit section having a switch, provided between the connection section and the power supply section and connected to the connection section, The system comprises a control unit that controls the switch, The circuit section is provided between the connection section and the power supply section and is connected to the connection section. The control unit sets a duty cycle, which is the ratio of the on-time to the switching period, and controls the switch according to the set duty cycle to adjust the current supplied to the connection section. Furthermore, the circuit section is provided in a number of units that is one or more, and fewer than the number of conductive paths. Multiple circuit sections are provided. The control unit synchronizes the on / off timing of each switch in each of the circuit units and performs duty cycle control. Power supply device.

2. The system includes a detection unit that detects the voltage value of any of the multiple circuit components, or the current value flowing through any of the multiple circuit components, The control unit determines whether or not an overcurrent state exists based on the detected value of the detection unit, and if it determines that an overcurrent state exists, it switches all of the switches to the off state. The power supply device according to claim 1.

3. The control unit selects and sets one of several duty cycles. The power supply device according to claim 1 or claim 2.

4. The number of duty cycle stages is the same as the number of conductive paths. The power supply device according to claim 3.

5. The first duty cycle is a value that adjusts the connection so that a reference current flows through it. The duty cycle of the Nth stage from the second stage onward is a value adjusted so that a current equal to N times the reference value flows through the connection point. The power supply device according to claim 4.

6. A power supply device for vehicles, The control unit sets the duty cycle based on at least one of the vehicle's outside temperature and a switching operation performed by the control unit. The power supply device according to claim 1 or claim 2.

7. All of the aforementioned switches are of the same model number. The power supply device according to claim 1 or claim 2.

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