JP6026382B2 - Power control device - Google Patents

Description

  The present invention relates to a power supply control apparatus that compensates for fluctuations in input voltage and outputs power at a predetermined voltage, and more particularly to supply a stable voltage power to an electric load by compensating for a battery voltage drop at engine start. The present invention relates to a suitable power supply control device.

  A vehicle is equipped with a control unit such as an ECU and various electric loads such as a lighting fixture, a display, a motor, and a solenoid, and it is necessary to supply electric power to each electric load with a stable voltage. Therefore, a DC / DC converter has been conventionally used as a power supply control device that controls so that a stable voltage power is supplied to the load, and the voltage is stepped up and down by the DC / DC converter to stabilize the voltage. ing.

  Also, in response to the electrification and increase in capacity of onboard equipment such as EPS and electric air conditioners, the voltage of the battery is boosted by a DC / DC converter to supply power to the motor inverter. Alternatively, in a 42V automobile power supply system including a 42V main battery and a 14V sub battery, a DC / DC converter is connected between two batteries for voltage conversion (step-up / step-down). Furthermore, in vehicles equipped with an idling stop system (ISS) that automatically stops the engine temporarily when the vehicle is temporarily stopped due to a signal, etc., a large current is supplied from the battery to the starter when the engine is restarted. For this reason, the voltage is boosted by a DC / DC converter to supply power to each electric load.

  By the way, since the DC / DC converter is provided with a booster circuit including an inductor or the like for voltage conversion, there is a problem that when this operates, heat is generated and a relatively large power loss occurs. Therefore, for the purpose of radiating heat during operation, heat radiating parts such as a heat radiating plate and a heat radiating case are installed in the DC / DC converter.

  In Patent Document 1, a heat generating component is mounted on a metal core substrate in order to improve heat dissipation from a heat generating component such as a booster circuit. Moreover, in patent document 1, the heat insulation part which penetrated and removed the metal core formed in the center of the metal core board | substrate in the thickness direction is provided. And it has been proposed that an electrical component that needs to avoid the heat radiated from the metal core is arranged directly above the heat insulating portion.

JP 2006-351634 A

  However, when a heat sink or a heat radiating case is installed in the power control device (DC / DC converter), there is a problem that the power control device becomes large. In addition, as described in Patent Document 1, when the heat insulating portion from which a part of the metal core is removed is formed, there arises a problem that the area of the metal core is reduced and heat dissipation is reduced. In order to reduce as much as possible the effect of heat dissipation due to the formation of the heat insulating portion, it is preferable to provide the heat insulating portion at a position as far as possible from the heat generating component. However, this increases the restrictions on the arrangement of the electrical components on the metal core substrate, and as a result, there is a possibility that a problem such as the need to enlarge the metal core substrate may occur.

  Moreover, since the power supply control device (DC / DC converter) incorporates noise generating components such as switching elements in the booster circuit, in addition to the problem of heat dissipation, the power supply control device radiates noise during operation. There is another problem of becoming a noise source. For this reason, circuit components that need to reduce the influence of noise from the booster circuit, such as a CPU that performs communication, digital arithmetic control, and the like, must be arranged as far as possible from the booster circuit.

A configuration example of a conventional power supply control device shown in FIG. FIG. 5 is a plan view and a cross-sectional view showing an example of the configuration of a conventional power supply control device 90. The cross-sectional view shown in FIG. 5B is a cross-sectional view taken along the line AA of the plan view shown in FIG. In this figure, the booster circuit 92 is arranged on the left side of the substrate 91 in the drawing, and the CPU 93 is arranged on the right side of the substrate 91 in the drawing, so that the CPU 93 is arranged as far as possible from the booster circuit 92. Thus, if it is necessary to arrange the distance between the CPU 93 and the booster circuit 92 as large as possible, there arises a problem that the power supply control device is increased in size.

  The present invention has been made in view of the above problems, and is a power supply control device that is easy to miniaturize by equalizing the heat generated from the booster circuit to improve heat dissipation and reducing the influence of noise from the booster circuit. The purpose is to provide.

In order to solve the above-mentioned problem, a first aspect of a power supply control device according to the present invention is a power supply control device for supplying electric power from a vehicle battery to an electric load at a stable voltage, and the voltage of the battery at the time of starting the engine A booster circuit that compensates for the decrease and stabilizes the voltage to a predetermined voltage and a control unit are mounted on the metal core substrate, and the metal core substrate includes a grounded metal core layer in an inner layer and sandwiches the metal core layer therebetween. A first ground layer and a second ground layer that are formed; the booster circuit includes a power unit and a boost control unit; the power unit is disposed on one surface of the metal core substrate; The step-up control unit and the control unit are disposed on the other surface of the metal core substrate, the first ground layer is used as the ground of the power unit, and the second graph And a switching means for turning on / off boosting in the power unit is disposed on a surface opposite to the control unit across the metal core substrate. It is characterized by being.

According to another aspect of the power supply control device of the present invention, the plurality of heat generating components are arranged so that at least a part thereof overlaps in a direction perpendicular to the surface of the metal core substrate with the metal core substrate interposed therebetween. Features.

In another aspect of the power supply control device of the present invention, the plurality of heat generating components are the power unit and the control unit .

  According to the present invention, it is possible to provide a power supply control device that can easily reduce the size by equalizing the heat generated from the booster circuit to improve heat dissipation and reducing the influence of noise from the booster circuit.

It is the top view and sectional drawing which show an example of a structure of the power supply control apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure of the power supply control apparatus which concerns on 1st Embodiment. It is the top view and sectional drawing which show an example of a structure of the power supply control apparatus which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows an example of a structure of the power supply control apparatus which concerns on 3rd Embodiment of this invention. It is the top view and sectional drawing which show an example of a structure of the conventional power supply control apparatus.

  A power supply control device according to a preferred embodiment of the present invention will be described in detail with reference to the drawings. Each component having the same function is denoted by the same reference numeral for simplification of illustration and description.

  Generally, when starting an engine of a vehicle, a large current is supplied to the starter, so that the battery voltage is greatly reduced. At this time, since it is necessary to supply electric power higher than a predetermined voltage to the electric load in operation, the voltage of the electric power supplied to the electric load is stabilized using, for example, a DCDC converter.

  When the engine is started, a large current is required in a short time, but the time during which the current continuously flows is about several seconds. Also, once the engine has started, even if it is a vehicle equipped with an idling stop system, the current continues to flow (several seconds) until the next start of the engine is required. In general, there is a long time. Accordingly, the operation of the DCDC converter also has characteristics that its operation time is short and the operation interval is long. Even when the substrate is enlarged in the surface direction when the DC / DC converter radiates heat, it takes time to transfer heat in the surface direction, and the heat generation of the DC / DC converter stops before transferring the heat to the enlarged portion. In addition, since it takes a long time until the next heat generation occurs, the heat of the substrate is dissipated and returns to a specified temperature. That is, even if the substrate is enlarged in the surface direction, the effect of lowering the temperature of the substrate is small. On the other hand, in the heat dissipation of the DCDC converter, it is effective to increase the speed of heat transfer in the surface direction of the substrate to equalize the heat. The present invention makes this possible by using a metal core substrate.

  The present invention provides, as a DCDC converter for supplying power to an electric load mounted on a vehicle, a power control device that equalizes heat generated during operation to facilitate heat dissipation and is easy to downsize. is there. In particular, it functions effectively in a vehicle equipped with an idling stop system in which the engine starts frequently and the DCDC converter operates frequently.

(First embodiment)
A power supply control apparatus according to a first embodiment of the present invention (hereinafter described as a DCDC converter) will be described below with reference to FIG. FIG. 1 is a plan view and a cross-sectional view illustrating an example of the configuration of the DCDC converter 100 of the present embodiment. The cross-sectional view shown in FIG. 5B is a cross-sectional view taken along the line AA of the plan view shown in FIG. FIG. 2 is a block diagram showing the configuration of the DCDC converter 100.

  The DCDC converter 100 of this embodiment uses a metal core substrate 110 as a substrate, and a booster circuit 120 and a control CPU 130 serving as a control unit are disposed thereon. For example, the control CPU 130 performs communication with the outside and digital arithmetic processing. Examples of the digital arithmetic processing include processing for determining the operation of the booster circuit 120. The booster circuit 120 includes a power unit 121 and a boost control unit 122. The power unit 121 of the booster circuit 120 is disposed on one surface of the metal core substrate 110, and the boost controller 122 and the control CPU 130 of the booster circuit 120 are disposed on the other surface of the metal core substrate 110.

  The metal core substrate 110 includes a metal core layer 111 as an inner layer, and further, a first ground layer 112 and a second ground layer 113 are formed with the metal core layer 111 interposed therebetween. Here, the first ground layer 112 is used as the ground of the power unit 121 disposed on one surface of the metal core substrate 110, and the ground of the boost control unit 122 and the control CPU 130 disposed on the other surface of the metal core substrate 110. It is assumed that the second ground layer 113 is used.

  The DC / DC converter 100 has an inductor (not shown) used for voltage conversion in the power unit 121 of the booster circuit 120, and heat is generated from the inductor when the booster circuit 120 is operated. Therefore, it is necessary to dissipate this heat appropriately. Therefore, in the present embodiment, the metal core substrate 110 is used as the substrate of the DC / DC converter 100, and the heat generated by the power unit 121 is equalized by using the temperature uniformity of the metal core substrate 110, so that the heat can be easily radiated. .

  The heat generated in the inductor of the power unit 121 is propagated to the metal core layer 111 of the metal core substrate 110, diffuses throughout the metal core layer 111, and is soaked. Thereby, heat is dissipated from the wide surface of the metal core substrate 110 to the outside.

  The control CPU 130 is also a component that generates a large amount of heat, and the heat generated by the control CPU 130 is diffused and uniformized throughout the metal core layer 111 of the metal core substrate 110. Thereby, heat is dissipated from the wide surface of the metal core substrate 110 to the outside. In a conventional substrate without the metal core layer 111, even if the power unit 121 and the control CPU 130 are arranged on different surfaces of the substrate, the power unit 121 and the control CPU 130 are separated from each other in the surface direction of the substrate in order to avoid heat concentration. Had to be mounted on. For this reason, it has been difficult to reduce the size of the entire substrate.

  On the other hand, in the DC / DC converter 100 according to the present embodiment, the heat generated by the heat-generating component can be diffused by the metal core layer 111. Therefore, a component that generates a large amount of heat, such as the power unit 121 and the control CPU 130, can be used as the metal core substrate. It is possible to arrange them in the surface direction of 110 or close to each other. The components are not limited to components that generate a large amount of heat, but can also be arranged in the plane direction or close to each other even in the case of components that are easily affected by heat and the heat generating components.

  As described above, according to the present embodiment, the heat generation from the booster circuit 120 is equalized to improve heat dissipation, so that the booster circuit is provided on the surface of the metal core substrate 110 facing the surface on which the booster circuit 120 is mounted. It is possible to provide the power supply control device 100 in which components can be mounted without considering the influence of the heat generation of 120 and the size can be easily reduced.

(Second Embodiment)
A power supply control device (hereinafter described as a DCDC converter) according to a second embodiment of the present invention will be described below with reference to FIG. FIG. 3 is a plan view and a cross-sectional view showing an example of the configuration of the DCDC converter 200 of the present embodiment. The cross-sectional view shown in FIG. 5B is a cross-sectional view taken along the line AA of the plan view shown in FIG.

  The DCDC converter 200 of this embodiment uses a metal core substrate 210 as a substrate, and a booster circuit 120 and a control CPU 130 are disposed thereon. The booster circuit 120 includes a power unit 121 and a boost control unit 122. The power unit 121 of the booster circuit 120 is disposed on one surface of the metal core substrate 210, and the boost controller 122 and the control CPU 130 of the booster circuit 120 are disposed on the other surface of the metal core substrate 210.

  The metal core substrate 210 includes a metal core layer 211 as an inner layer, and further, a first ground layer 212 and a second ground layer 213 are formed with the metal core layer interposed therebetween. Here, the first ground layer 212 is used as the ground of the power unit 121 disposed on one surface of the metal core substrate 210, and the ground of the boost control unit 122 and control CPU 130 disposed on the other surface of the metal core substrate 210. The second ground layer 213 is used.

  Similar to the DCDC converter 100 of the first embodiment shown in FIG. 2, the DCDC converter 200 is connected to the battery 10 and the electric load 20, and when the voltage of the battery 10 drops below a predetermined value, the power of the booster circuit 120 is increased. The voltage is boosted by the unit 121 and supplied to the electric load 20. Further, the control CPU 130 is configured to output a predetermined control signal to the boost control unit 122 according to the control signal, for example, when a control signal is input from the ECU 30 which is the host control system, and the boost control unit 122 further controls the power unit 121. Has been.

  The DC / DC converter 200 has an inductor used for voltage conversion in the power unit 121 of the booster circuit 120, and heat is generated from the inductor when the booster circuit 120 is operated. Therefore, it is necessary to dissipate this heat appropriately. Therefore, in the present embodiment, the metal core substrate 210 is used as the substrate of the DC / DC converter 200, and the heat generated by the power unit 121 is equalized by using the heat equalization property of the metal core substrate 210 to facilitate heat dissipation. .

  The heat generated in the inductor of the power unit 121 is propagated to the metal core layer 211 of the metal core substrate 210 and diffused throughout the metal core layer 211 to be equalized. As a result, heat is radiated from the wide surface of the metal core substrate 210 to the outside.

  The booster circuit 120 also incorporates switching means (not shown) for turning on / off boosting in the power unit 121. The switching element operates the boosting function in the power unit 121 when the voltage of the battery 10 is equal to or lower than a predetermined value, and bypasses the boosting function of the power unit 121 without operating when the voltage is higher than the predetermined value. Thereby, when the voltage of the battery 10 is equal to or lower than the predetermined value, the electric power boosted by the power unit 121 is supplied to the electric load 20, while when the voltage of the battery 10 is higher than the predetermined value, the boosting of the power unit 121 is performed. Electricity is supplied to the electric load 20 while bypassing the function and maintaining the battery voltage.

  In the above description, the switching means is described as being built in the booster circuit 120. However, the present invention is not limited to this. For example, the switching means is disposed on the metal core substrate 210 outside the booster circuit 120, and the voltage of the battery 10 is predetermined. You may comprise so that the power part 121 may be bypassed when it is below a value. Further, the switching unit is not limited to the switching unit that switches the operation of the power unit 121 described above, and another switch unit may be disposed on the same surface as the power unit 121 of the metal core substrate 210.

  Since the DC / DC converter 200 has the switching means as described above, there is a problem that noise is generated when the switching means is activated. In order to reduce the influence of this noise on the control CPU 130 as much as possible, the DC / DC converter 200 of the present embodiment is configured such that the metal core layer 211 of the metal core substrate 210 becomes a shield layer that shields noise.

  In order to use the metal core layer 211 as a shield layer that shields noise generated by the switching means, in this embodiment, the metal core layer 211 is connected to a predetermined ground so as to function as a ground. In order to use the metal core layer 211 as the ground, it may be connected to another ground, or may be connected to the positive electrode or the negative electrode of the battery 10. Thereby, the metal core layer 211 serves as a ground and functions as a shield layer that shields noise.

  As described above, in the DC / DC converter 200 of the present embodiment, since the metal core layer 211 can be used as a shield layer against noise, the metal core layer 211 is provided between the control CPU 130 and the noise source switching means. By arranging each of them so as to be sandwiched, it is possible to reduce the influence of noise that the control CPU receives from the switching means. In the DC / DC converter 200 shown in FIG. 1, since the booster circuit 120 has built-in switching means, the control CPU 130 is placed on the other surface opposite to one surface of the metal core substrate 210 on which the booster circuit 120 is mounted. As a result, the noise from the switching means is shielded by the metal core layer 211 and the influence on the control CPU 130 is reduced.

  Since the metal core layer 211 functions as a shield layer that shields noise, when the control CPU 130 is disposed on the surface opposite to the booster circuit 120 across the metal core layer 211, the control CPU 130 is disposed close to the booster circuit 120. It is also possible. In FIG. 1, the control CPU 130 is arranged at a position that partially overlaps the booster circuit 120 in the vertical direction. Even if the control CPU 130 is arranged close to the booster circuit 120 in this way, the noise radiated from the switching means of the booster circuit 120 is shielded by the metal core layer 211, so that the control CPU 130 is almost affected by the noise. Absent. In this embodiment, by disposing the control CPU 130 close to the booster circuit 120, the metal core substrate 210 can be made small, and the DC / DC converter 200 can be downsized.

  As described above, according to the present embodiment, the heat generation from the booster circuit 120 is equalized to increase heat dissipation, and the influence of noise from the booster circuit 120 is reduced to easily reduce the size of the power supply control device 200. Can be provided.

(Third embodiment)
A power supply control device (DCDC converter) according to a third embodiment of the present invention will be described below with reference to FIG. FIG. 4 is a cross-sectional view showing an example of the configuration of the DCDC converter 300 of the present embodiment. The cross-sectional view shown in the figure is a cross-sectional view taken along the line AA of the plan view shown in FIG.

  Similar to the DCDC converter 200 of the second embodiment, the DCDC converter 300 of the present embodiment is formed so that the metal core layer 311 of the metal core substrate 310 serves as a ground and serves as a shield layer. Thus, by mounting the control CPU 130 on the surface opposite to the surface on which the booster circuit 120 is mounted on the metal core substrate 310, the influence of noise radiated from the booster circuit 120 on the control CPU 130 is greatly reduced. be able to. As a result, the control CPU 130 can be placed close to the booster circuit 120, and the metal core substrate 310 can be made smaller and the DCDC converter 300 can be made smaller.

  Furthermore, in the DCDC converter 300 according to the present embodiment, the metal core layer 311 is electrically connected to the first ground layer 312 and the second ground layer 313 through the connection portion 314. By connecting the metal core layer 311 to the first ground layer 312 and the second ground layer 313, the function of the metal core layer 311 as the ground is reinforced. As a result, the function of the metal core layer 311 as a shield layer is also enhanced. The number of connection portions 314 that electrically connect the metal core layer 311 to the first ground layer 312 and the second ground layer 313 increases as the number of the connection portions 314 increases. As a result, the function as a shield layer is further strengthened.

  In each of the above embodiments, the first ground layer 312 and the second ground layer 313 are provided as the ground of the circuit component mounted on the metal core substrate 310. The first ground layer 312 is used as the ground of the circuit component mounted on one surface of the metal core substrate 310, and the second ground is used as the ground of the circuit component mounted on the other surface of the metal core substrate 310. Layer 312 is used.

  Instead of providing the two ground layers of the first ground layer 312 and the second ground layer 313, the metal core layer 311 can be used as one common ground. In other words, all circuit components arranged on both surfaces of the metal core substrate 310 can be connected to the metal core layer 311 as a ground. As a result, the first ground layer 312 and the second ground layer 313 are not required, and the cost can be reduced.

  According to the present embodiment, by further strengthening the function of the metal core layer 311 as the ground, the heat generated from the booster circuit 120 is soaked to improve heat dissipation, and the influence of noise from the booster circuit 120 is further reduced. Thus, it is possible to provide the power supply control device 300 that can be easily downsized.

  Note that the description in the present embodiment shows an example of the power supply control device according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of the power supply control device in the present embodiment can be appropriately changed without departing from the spirit of the present invention.

10 battery 20 electric load 30 ECU
100, 200, 300 Power supply control device (DCDC converter)
110, 210, 310 Metal core substrate 111, 211, 311 Metal core layer 112, 212, 312 First ground layer 113, 213, 313 Second ground layer 120 Boost circuit 121 Power unit 122 Boost control unit 130 Control CPU
314 connection

Claims (3)

A power supply control device for supplying electric power from a vehicle battery to an electric load at a stable voltage,
A booster circuit that compensates for the voltage drop of the battery when starting the engine and stabilizes it to a predetermined voltage and a control unit are mounted on the metal core board ,
The metal core substrate includes a grounded metal core layer as an inner layer, and includes a first ground layer and a second ground layer formed with the metal core layer interposed therebetween,
The booster circuit includes a power unit and a boost control unit,
The power unit is disposed on one surface of the metal core substrate, the boost control unit and the control unit are disposed on the other surface of the metal core substrate,
The first ground layer is used as the ground of the power unit, and the second ground layer is used as the ground of the boost control unit and the control unit,
Switching means for turning on / off boosting in the power unit is disposed on a surface opposite to the control unit across the metal core substrate .   A plurality of heat generating components are arranged so that at least a part thereof overlaps in a direction perpendicular to the surface of the metal core substrate with the metal core substrate interposed therebetween.
  The power supply control device according to claim 1.   The plurality of heat generating components are the power unit and the control unit.
  The power supply control device according to claim 2.

Images