JP6502838B2 - Electromagnetic device drive device, electronic control device for vehicle, and vehicle - Google Patents

Description

The present invention relates to an electromagnetic device drive device including a booster circuit , an electronic control device for a vehicle, and a vehicle, and in particular, shortening a charging time of an output capacitor of the booster circuit to shorten recovery time to a predetermined boosted voltage. The present invention relates to an electromagnetic device drive device capable of driving the vehicle, an electronic control device for a vehicle equipped with the electromagnetic device drive device, and a vehicle equipped with the electromagnetic device drive device .

  Conventionally, a ground side terminal of a solenoid actuator for opening and closing a fuel injection valve, which is an electromagnetic device, as an electromagnetic device drive device including an electromagnetic device drive circuit that regenerates back electromotive force of the electromagnetic device driven by the boost power supply An "internal combustion engine control device" is known in which an anode of a regenerative diode is connected to the cathode of the diode and a cathode of the diode is connected to a voltage output terminal of the output capacitor (see Patent Document 1).

  FIG. 2 is a view showing a part of the internal combustion engine control device described in Patent Document 1. As shown in FIG. When the fuel injection period starts, the control circuit 210 applies a high voltage from the booster circuit 201 to the INJ 205 by turning on the TR 202 and the TR 204 to quickly open the fuel injection valve. After the predetermined time has elapsed, the TR 202 is turned off, and then the TR 206 is turned on / off to hold the valve open state. Thereafter, when the fuel injection period ends, the TR 206 and the TR 204 are turned off to stop the power supply to the INJ 205.

  The current flowing through the INJ 205 due to the back electromotive force generated in the INJ 205 after stopping the current flows into the booster circuit 201 via the diode D 207 and the resistor R 208 and is regenerated by the booster circuit 201. Thereby, for example, a boost power supply capacitor (not shown) provided in the output circuit of the boost circuit 201 is charged.

  In addition to the effect of reducing power consumption by effectively utilizing the back electromotive force of the electromagnetic device (the actuator in the above example), such a regenerative circuit is a booster circuit in which the output voltage (terminal voltage) is temporarily discharged to decrease. By charging the output capacitor of the above with the booster circuit itself, charging through the regeneration circuit also has an effect of shortening the time for which the output voltage recovers to a predetermined boosted voltage.

  However, in the above-described conventional control device, regeneration of the output capacitor is performed only at the time of valve closing when energization of the solenoid is shut off, so there is a limit to shortening the time until the output voltage of the booster circuit recovers. is there.

  On the other hand, particularly in a diesel engine, it is known that the combustion performance is improved by performing multistage injection in which fuel is injected in multiple steps in one combustion cycle, and in this case, the predetermined time In order to perform the desired number of fuel injections inside, it is necessary to shorten the charging time of the output capacitor of the booster circuit to shorten the fuel injection interval.

Patent No. 4474423

  From the above background, it is desired to shorten the charging time of the output capacitor of the booster circuit and shorten the recovery time up to a predetermined boosted voltage in the electromagnetic device driving device including the booster circuit.

One aspect of the present invention is an electromagnetic device drive device, which is a booster circuit including an output capacitor, and a first drive circuit for driving a first electromagnetic device by supplying a boosted voltage output from the output capacitor. And turning on and off a first switch provided between one end of the second electromagnetic device different from the first electromagnetic device and the ground line to energize a voltage from a power supply different from the voltage boosting circuit. A second drive circuit for driving the second electromagnetic device, and a wiring line whose cathode is connected to the one end of the second electromagnetic device and which becomes the ground potential when the first switch is turned off Electrically in series with each other between a voltage regulator diode connected at the anode, the one end of the second electromagnetic device, and the output end of the boosted voltage of the output capacitor And a control circuit for controlling on / off of the second switch, wherein the control circuit is configured to operate when the voltage at the output end of the output capacitor is less than a predetermined boosted voltage. And the second switch is turned on.
According to another aspect of the present invention, the first electromagnetic device is a solenoid actuator that opens and closes a fuel injection valve of an internal combustion engine.
Another aspect of the present invention is a vehicle electronic control device including any one of the above-described electromagnetic device drive devices.
The further another aspect of this invention is a vehicle provided with the said electromagnetic device drive device.

It is an electric circuit diagram of an electromagnetic device drive concerning one embodiment of the present invention. It is a figure which shows an example of the conventional solenoid valve control circuit.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The electromagnetic device drive device according to the present embodiment is mounted, for example, on a vehicle, and drives a solenoid actuator, which is an electromagnetic device that opens and closes a fuel injection valve of an internal combustion engine of the vehicle. However, the present invention is not limited to this, and can be applied to a drive device for driving a general electromagnetic device (or inductive load) widely.

FIG. 1 is a circuit diagram of an electromagnetic device drive apparatus according to an embodiment of the present invention.
The driving device 10 receives a power supply from a battery (not shown) and outputs a predetermined boosted voltage larger than a voltage (feed voltage) V _{BAT of the} power supply, and a boosted voltage output from the booster circuit 100. A first control circuit 104 for driving the first electromagnetic device L102 in response to the supply of the second electromagnetic device L106 by a voltage different from the boosted voltage (for example, the supply voltage V _BAT ). And a second control circuit 108 to drive. Here, the first electromagnetic device L102 is, for example, a solenoid actuator that controls a fuel injection valve (not shown) of an internal combustion engine of a vehicle on which the drive device 10 is mounted.

The booster circuit 100 includes a coil L110 having one end connected to the power supply line of the voltage V _BAT , and a switch Tr112 provided between the other end of the coil L110 and the ground line to turn on / off energization of the coil L110. , A diode D114 whose anode is connected to the other end of the coil L110, an output capacitor C116 which is charged by a current flowing out from the coil L110 via the diode D114 and outputs a predetermined boosted voltage, and turns on and off the transistor TR112 to boost operation. And a boost control circuit 118 that controls the

The first control circuit 104 selectively supplies the output voltage from the booster circuit 100 and the feed voltage V _BAT from the battery to one end of the first electromagnetic device L102 through the transistors Tr120 and Tr122, respectively. The other end of the one electromagnetic device L102 is connected to the ground line via the transistor 124. The transistors 120 and 122 are, for example, p-channel MOSFETs, and the transistor 124 is, for example, an n-channel MOSFET.

  The on / off of the transistors 120 to 124 is controlled by the injection control circuit 126 for controlling the operation of the first electromagnetic device L102, which is an actuator for opening and closing the fuel injection valve. When the fuel injection valve is opened, the injection control circuit 126 turns on the Tr 120 and the Tr 124 while keeping the Tr 122 off, and causes a large current to flow to the first electromagnetic device L 102 by the output voltage (boosted voltage) from the boost circuit 100. Then, the injection valve is immediately opened, and then the Tr 120 is turned off, the Tr 122 is repeatedly turned on and off, and the injection valve is maintained in the open state. Thereafter, when a predetermined fuel injection time has elapsed, the injection control circuit 126 turns off the transistors 122 and 124 and cuts off the current to the first electromagnetic device L102.

  The diode D128 is a flywheel diode for causing a counter electromotive current to flow to the first electromagnetic device L102 at the moment when the transistor 122 is turned off when the transistor 122 is turned on and off to maintain the valve open state.

The second control circuit 108 connects one end of the second electromagnetic device L106 to another power supply different from the booster circuit (boost power supply) 100, for example, the power supply line of a battery (feed voltage V _BAT ), The other end of the electromagnetic device L106 is connected to the ground line via the Tr130. The second control circuit 108 also includes a load control circuit 136 that turns on and off the Tr 130 via the Tr 132 and Tr 134 that form a push-pull circuit. Here, the Tr 130 corresponds to the first switch.

  In addition, a connection point (point A in the figure) between the anode of the regenerative diode D140 and the second electromagnetic device L106, and a gate line (point C in the figure) of the Tr 130 which becomes the ground potential when the first switch Tr130 turns off. And a zener diode (voltage regulator diode) D142.

  Furthermore, a first electromagnetic device L102 of a connection point (point A in the figure) between the second electromagnetic device L106 and the first switch Tr130 inside the second control circuit 108 and the output capacitor C116 of the booster circuit 100. Between the line connected to the end of the power supply side (point B in the drawing) and the regenerative diode D140 (anode at the point A in the figure) for regenerating the back electromotive force of the second electromagnetic device L106 to the output capacitor C116 A cathode is connected to the point B in the figure), and a switch circuit SW150 for turning on and off the conduction of the diode D140 from the point A in the figure.

  Here, the switch circuit SW150 is controlled by the regeneration control circuit 152. The regenerative control circuit 152 measures the voltage (point B voltage) applied to the point B in the figure by a voltage dividing circuit configured by two resistors R154 and R156, and the measured point B voltage is less than a predetermined threshold voltage. Switch circuit SW150 is turned on (that is, the conduction from point A to the anode of switch circuit SW150 is turned on), and when the B point voltage is equal to or higher than the threshold voltage, switch circuit SW150 is turned off. . Here, the threshold voltage can be, for example, a value equal to a predetermined boosted voltage (prescribed boosted voltage) to be output by the booster circuit 100.

  Thereby, in the regeneration control circuit 152, the charge of the output capacitor C116 of the booster circuit 100 is discharged toward the first electromagnetic device L102, and the voltage between the terminals of the output capacitor C116 (therefore, the voltage of the booster circuit 100 at point B in FIG. When the output voltage) becomes less than the specified boosted voltage, the switch circuit SW150 can be turned on to regenerate the back electromotive force generated in the second electromagnetic device L106 to the output capacitor C116 via the diode D140. .

  The switch circuit SW150 corresponds to the second switch, and is configured by a MOSFET or a solid state relay in which the source and drain are turned on and off by controlling the gate voltage as in Tr112, for example. Can. Further, the regeneration control circuit 152 can be configured by, for example, a digital circuit configured using a comparator or the like, a microcomputer, or an application specific integrated circuit (ASIC).

  The electromagnetic device drive device 10 having the above configuration causes the voltage at point B to have a predetermined threshold voltage when the back electromotive force is generated in the second electromagnetic device L106 by turning off the first switch Tr130. If the switch circuit SW150 sets the switch SW150 to ON due to less than (for example, less than the specified boosted voltage to be output by the booster circuit 100), the back electromotive force is transmitted via the switch circuit SW150 and the regenerative diode D140. The output capacitor C116 of the booster circuit 100 is regenerated.

  Here, as described above, since the second electromagnetic device L106 is a device different from the first electromagnetic device L102 for opening and closing the fuel injection valve, the first electromagnetic device L106 is turned off only at the end of the fuel injection period. The second electromagnetic device L106 may be turned on and off more frequently than the device L102. As a result, compared to the conventional control device in which energy is regenerated to the output capacitor of the booster circuit only at the end of the fuel injection period, the frequency of energy regeneration to the output capacitor C116 is increased to shorten the recovery time to a predetermined boosted voltage. can do.

  Further, in the present electromagnetic device driving apparatus 10, the Zener diode D142 is provided between the anode side (point A in the drawing) of the regenerative diode D140 and the wiring line (point C in the drawing) which becomes the ground potential during regeneration. The voltage due to the back electromotive force generated in the second electromagnetic device L106 by the turning off of the Tr 130 is quickly reduced to the breakdown voltage of the Zener diode D142. Therefore, it is possible to quickly reduce the magnetic field generated by the second electromagnetic device L106, and secure good dynamic characteristics (for example, delay time at the time of off, etc.) of the electromagnetic device L106.

  Here, the breakdown voltage of the Zener diode D142 is originally applied to the point B in the figure via the diode D140 so that the output capacitor C116 is not charged more than the specified boosted voltage (that is, it is not overcharged). It is desirable to set the voltage so that the voltage does not exceed the specified boosted voltage. However, if the breakdown voltage of the Zener diode D142 is set to the same value as the specified boosted voltage, the back electromotive force generated in the second electromagnetic device L106 is regenerated from when the voltage at point A falls to the specified boosted voltage. Therefore, it is not possible to charge the output capacitor C116 close to the specified boosted voltage by the back electromotive force that is attenuated in time. In addition, the back electromotive force of L106 flowing to the ground via the Zener diode D142 is wastefully consumed without being used for regeneration until the point A voltage decreases and reaches the specified boosted voltage.

  On the other hand, when the breakdown voltage of the Zener diode D142 is set higher than the specified boosted voltage, there is a possibility that the output capacitor C116 may be overcharged to the specified boosted voltage or more depending on the magnitude of the back electromotive force.

  In the present electromagnetic device driving device 10, when the regeneration control circuit 152 determines that the output voltage is less than a predetermined threshold (for example, less than a specified boosted voltage value) according to the output voltage of the booster circuit 100 (voltage at point B in FIG. Since the switch circuit SW150 is turned on, the output capacitor C116 is not overcharged even if the breakdown voltage of the Zener diode D142 is set higher than the specified boosted voltage. Therefore, since the breakdown voltage of the Zener diode D142 can be set to a value equal to or higher than the specified boosted voltage value, the power flowing into the ground through the Zener diode D142 in the counter electromotive force generated in the electromagnetic device L106 is reduced. Thus, it is possible to improve the regeneration efficiency (the ratio of the regenerated electric power (energy) to the total amount of the back electromotive force (energy) of L106).

  In the present embodiment, the switch circuit SW150 is inserted on the anode side of the regenerative diode D140. However, the switch circuit SW150 may be provided on the cathode side of the diode D140.

  10: electromagnetic device driving apparatus, 100: booster circuit, L102: first electromagnetic output bias, 104: first control circuit, L106: second electromagnetic device, 108: ... Second control circuit, L110: coil, Tr112, Tr120, Tr122, Tr124, Tr130, Tr132, Tr134: transistor, D114, D128, D140: diode, C116: output capacitor, 118: Step-up control circuit 126: injection control circuit 136: load control circuit SW150: switch circuit 152: regeneration control circuit R154, R156: resistance.

Claims (4)

A booster circuit comprising an output capacitor;
A first drive circuit for driving a first electromagnetic device by energizing a boosted voltage output from the output capacitor;
By turning on and off a first switch provided between one end of the second electromagnetic device different from the first electromagnetic device and the ground line, a voltage from a power supply different from that of the booster circuit is energized to A second drive circuit for driving the two electromagnetic devices;
A constant voltage diode in which a cathode is connected to the one end of the second electromagnetic device, and an anode is connected to a wiring line which becomes a ground potential when the first switch is turned off;
A regenerative diode and a second switch electrically connected in series with each other between the one end of the second electromagnetic device and the output end of the boosted voltage of the output capacitor;
A control circuit that controls on / off of the second switch;
Equipped with
The control circuit is configured to turn on the second switch when the voltage at the output of the output capacitor is less than a predetermined boosted voltage.
Electromagnetic device drive. The first electromagnetic device is a solenoid actuator that opens and closes a fuel injection valve of an internal combustion engine.
An electromagnetic device drive according to claim 1.   An electronic control unit for a vehicle comprising the electromagnetic device drive unit according to claim 1.   The vehicle provided with the electromagnetic device drive device of Claim 1 or 2.

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