JP5241761B2 - Vehicle power supply system - Google Patents

Description

  The present invention relates to a vehicle power supply system, and more particularly to a vehicle power supply system that allows a driver to feel the acceleration feeling of the vehicle.

  A conventional vehicle power supply system includes a battery and a DC / DC converter, and the DC / DC converter is connected between a booster circuit that boosts the terminal voltage of the battery, and a terminal of the battery and an output terminal of the booster circuit. And a capacitor. An electric device that can operate even when the terminal voltage of the battery drops beyond a predetermined range is connected to the input side of the DC / DC converter. / It is connected to the output side of the DC converter. Further, the battery stores the generated power of the generator and supplies the electric power to the rotating machine of the turbocharger (see, for example, Patent Document 1).

Japanese Patent No. 38858771

  In the conventional vehicle power supply system, since the electric power of the battery is supplied to the rotating machine of the turbocharger, a large current or a high voltage cannot be supplied to the field winding of the rotating machine. Therefore, when the driver tried to accelerate by depressing the accelerator, a response delay due to the time constant of the field winding occurred from the acceleration request timing to driving the turbocharger, and the driver could not accelerate at the timing desired by the driver .

  The present invention has been made in order to solve such problems, and in a low speed range, an electric double layer capacitor and a generator serve as a power supply power source for a turbocharger rotating machine, and the field of the rotating machine Electric current is applied to the windings and the field windings of the generator, the response delay from the acceleration command to driving the turbocharger is suppressed, and the driver can feel the acceleration and the electric double layer capacitor An object of the present invention is to obtain a vehicle power supply system that can realize downsizing.

  A vehicle power supply system according to the present invention includes a compressor that is disposed in an intake system of an engine and compresses intake gas, is coaxially attached to a rotation shaft of the compressor, is disposed in an exhaust system of the engine, and is driven by exhaust gas. And a turbocharger having a rotating machine coaxially mounted on the rotating shaft, an inverter for converting DC power into AC power and supplying the AC to the rotating machine, and driven by the engine to generate AC power Connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring, and the output voltage of the rectifier differs. A first DC / DC converter that converts the voltage value into a DC voltage and outputs the voltage, and is connected to the first DC / DC converter via a low-voltage side wiring. A battery for supplying electric power to the vehicle-mounted load, and a second DC / DC connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier into a DC voltage of a different voltage value A converter, an electric double layer capacitor connected to the second DC / DC converter, the first DC / DC converter and the second DC / DC converter are driven and controlled, and the electric power generated by the generator is supplied to the battery and the electric And a control circuit for driving the rotating machine by driving the inverter and controlling the inverter. The inverter, the field winding of the rotating machine, and the field winding of the generator are connected to the high-voltage side wiring, and the control circuit decelerates to reduce the engine speed to a predetermined speed. Then, the second DC / DC converter is driven and controlled so that the voltage of the high-voltage side wiring becomes a first voltage higher than the rated voltage of the battery, and the field winding of the generator, and the rotating machine The field winding is energized, and the state is maintained until re-acceleration.

  According to this invention, when the control circuit receives the acceleration command, the field current is applied to the field winding of the rotating machine, and an induced electromotive force is generated. Therefore, there is no response delay due to the time constant of the field winding, and when AC power is supplied to the rotating machine via the inverter, the rotating machine is driven quickly. As a result, the vehicle body is accelerated rapidly in accordance with the driver's accelerator operation, and the driver can feel a sense of acceleration.

  The high-voltage side wiring is held at a first voltage higher than the rated voltage of the battery, and the field current is applied to the field winding of the generator. When the engine speed increases and the generator's power generation speed is reached, the generator instantaneously generates power, and the combined output of the generator output and the electric double layer capacitor output is supplied to the inverter. . As a result, part of the large current supplied to the rotating machine is covered by the power generated by the generator, and the electric double layer capacitor and the second DC / DC converter can be downsized.

It is a schematic block diagram which shows the structure of the vehicle power supply system which concerns on Embodiment 1 of this invention. 1 is a circuit configuration diagram of a vehicle power supply system according to Embodiment 1 of the present invention. It is a figure which shows the output characteristic of the generator used for the vehicle power supply system which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the structure of the 2nd DC / DC converter used for the vehicle power supply system which concerns on Embodiment 1 of this invention. It is a figure explaining the control method of the 2nd DC / DC converter 25 in the low frequency area in the vehicle power supply system concerning Embodiment 1 of this invention. It is a figure explaining the operation | movement in the low speed area of the vehicle power supply system which concerns on Embodiment 1 of this invention. It is a figure explaining the operation | movement in the low speed area of the vehicle power supply system of a comparative example. It is a circuit block diagram of the vehicle power supply system which concerns on Embodiment 2 of this invention. It is a circuit block diagram of the vehicle power supply system which concerns on Embodiment 3 of this invention.

Embodiment 1 FIG.
1 is a schematic configuration diagram showing a configuration of a vehicle power supply system according to Embodiment 1 of the present invention, and FIG. 2 is a circuit configuration diagram of the vehicle power supply system according to Embodiment 1 of the present invention.

  1 and 2, a vehicle power supply system includes a turbocharger 5 connected to an intake / exhaust system of an engine 1 that is an internal combustion engine, and a generator 17 that is driven by the rotational torque of the engine 1 to generate AC power. A rectifier 22 that rectifies and outputs AC power generated by the generator 17 to DC power, a first DC / DC converter 24 that converts the output voltage of the rectifier 22 into DC voltages of different voltage values, and a rectifier The second DC / DC converter 25 that converts the output voltage 22 into a DC voltage having a different voltage value and outputs the DC voltage, and a battery that is charged by the DC power converted by the first DC / DC converter 24 and supplies power to the in-vehicle load 30 26, an electric double layer capacitor 27 for storing the DC power converted by the second DC / DC converter 25, and the DC power for AC power Based on the inverter 28 supplied to the armature winding 13 of the rotating machine 9 mounted on the turbocharger 5, the rotational speed f of the engine 1, the terminal voltage Vc of the electric double layer capacitor 27, etc. And a control circuit 31 that controls driving of the second DC / DC converters 24 and 25, the inverter 28, and the like.

The turbocharger 5 is fixed to the turbine 6 disposed in the exhaust system 15 of the engine 1, the compressor 8 disposed in the intake system 16 of the engine 1, and coaxial with the rotational shaft 7. And a rotating machine 9 attached to the.
The rotating machine 9 is a field-controlled rotating machine, and includes a rotor 10 fixed coaxially to the rotating shaft 7, a stator core 12 disposed so as to surround the rotor 10, and the stator core 12. The stator 11 is composed of an armature winding 13 that is wound and generates torque in the rotor 10, and a field winding 14 that generates a field magnetomotive force.

The generator 17 connects the pulley 3b to a pulley 3a fixed to the crankshaft 2 of the engine 1 via a belt 4, and converts the driving force of the engine 1 transmitted via the belt 4 into AC power. The generator 17 is a Landell type AC generator including a claw pole type rotor 18 having a field winding 19 and a stator 20 having a three-phase AC winding 21.
The rectifier 22 is configured as a three-phase full-wave rectifier circuit composed of a diode bridge circuit in which three diode pairs formed by connecting two diodes 23 in series are connected in parallel, and the AC induced in the three-phase AC winding 21. Rectify power to DC power. The rectifier 22 is configured separately from the generator 17, but may be built in the generator 17.

The battery 26 is a secondary battery such as a lead storage battery or a nickel / cadmium storage battery, and constitutes a low-voltage system on-vehicle power source of, for example, 14 V (rated voltage). The battery 26 is connected to a low-voltage side wiring 35 that connects the output voltage terminal of the first DC / DC converter 24 and the in-vehicle load 30. The in-vehicle load 30 is an electric device such as an air conditioner or an audio device mounted on the vehicle, and is driven by the battery 26.
The electric double layer capacitor 27 is connected to the high voltage side wiring 34 that connects the high voltage side output terminal 22 a of the rectifier 22 and the input voltage terminal of the first DC / DC converter 24 via the second DC / DC converter 25.

The inverter 28 is configured by connecting, in parallel, three element pairs formed by connecting semiconductor switching elements 29 such as MOSFETs and IGBTs in series, and converts DC power supplied to the high-voltage side wiring 34 into AC power. To do.
One end of the field winding 19 of the generator 17 and the field winding 14 of the rotating machine 9 is connected to the high-voltage side wiring 34.

Next, the operation of the turbocharger 5 will be described.
The intake gas A is supplied to the engine 1 through the intake system 16 and burned inside the engine 1. The exhaust gas B after combustion is exhausted to the outside through the exhaust system 15, and the turbine 6 is driven by the exhaust gas B that flows through the exhaust system 15. As a result, the compressor 8 fixed to the rotating shaft 7 of the turbine 6 is rotationally driven, and the intake gas A is supercharged to atmospheric pressure or higher.
When the driver tries to accelerate by operating the accelerator in the low speed range, sufficient power is required for about 1 to 2 seconds until the engine 1 reaches a predetermined speed or more and the exhaust gas B obtains sufficient fluid power. Cannot be supplied to the turbine 6, the reaction of the compressor 8 is delayed, and a so-called turbo lag phenomenon occurs.

  Therefore, the AC power converted by the inverter 28 is supplied to the rotating machine 9 and the rotating machine 9 is driven. Thereby, even when the fluid power of the exhaust gas B cannot be sufficiently obtained at a low speed at which turbo lag occurs, the driving force is applied to the rotating shaft 7, the compressor 8 can be driven quickly, and the occurrence of turbo lag is suppressed.

Here, since the rotating machine 9 has the field winding 14 for generating the field magnetomotive force, there is a response delay due to the time constant of the field winding 14. Therefore, when the driver depresses the accelerator and accelerates, a response delay occurs from the acceleration request timing until the rotating machine 9 is driven, and the drive of the compressor 8 is delayed correspondingly, and the driver cannot accelerate at the timing desired by the driver.
The present invention suppresses a response delay due to the time constant of the field winding 14 and realizes acceleration at a timing desired by the driver in a low speed region. The low speed region is a rotational speed region where the rotational speed of the engine 1 is around 1000 rpm.

Next, the operation of the generator 17 will be described.
Current is supplied to the field winding 19 of the rotor 18 to generate magnetic flux. Thereby, the N pole and the S pole are alternately formed in the circumferential direction on the outer peripheral portion of the rotor 18. Then, the rotational torque of the engine 1 is transmitted to the shaft of the rotor 18 and the rotor 18 is driven to rotate. Therefore, a rotating magnetic field is applied to the three-phase AC winding 21 of the stator 20, and an electromotive force is generated in the three-phase AC winding 21. This AC electromotive force is rectified to DC power by the rectifier 22 and output.

  Here, the output characteristics of the generator 17 will be described. FIG. 3 is a diagram showing the output characteristics of the generator used in the vehicle power supply system according to Embodiment 1 of the present invention. The vertical axis represents the generated power (output power), and the horizontal axis represents the rotational speed f of the engine 1. is there. Since the rated voltage of the battery 26 is 14V and the voltage exchange ratio N of the first and second DC / DC converters 24 and 25 is 1 and 1/2 as will be described later, the output voltage of the generator 17 is Set to 14V and 28V.

  As can be seen from FIG. 3, when the output voltage is set to 14V, the generator 17 can generate power in a region where the rotational speed f is α or more, and when the output voltage is set to 28V, the rotational speed f is Power can be generated in a region higher than β higher than the idling region. The generator 17 can output large generated power when the output voltage is set to 14 V in the region where the rotational speed f is less than β, and the output voltage is 28 V in the region where the rotational speed f is β or more. When this is set to, a large amount of generated power can be output.

  In an automobile, usually, the rotation speed f of the engine 1 is often in the range of 1000 rpm to 3000 rpm. Therefore, the power transmission ratio of the power transmission mechanism between the engine 1 and the rotor 18 of the generator 17 is obtained so that the output characteristics shown in FIG. 3 are obtained when the rotational speed f of the engine 1 is in the range of 1000 rpm to 3000 rpm. Is adjusted.

  Next, a specific configuration of the second DC / DC converter 25 will be described with reference to FIG. FIG. 4 is a circuit diagram showing a configuration of a second DC / DC converter used in the vehicle power supply system according to Embodiment 1 of the present invention. Note that the first DC / DC converter 24 is also configured in the same manner as the second DC / DC converter 25, and therefore the description thereof is omitted here.

  The second DC / DC converter 25 has two series formed by connecting two MOSFETs 51 to 54 as switching elements on the low voltage side and the high voltage side between the input voltage terminals VaH and VaL and the output voltage terminals VbH and VbL. And two-stage circuits A1 and A2 comprising smoothing capacitors Cs1 and Cs2 connected in parallel to each series body. The circuits A1 and A2 are connected in series, the circuit A1 is a rectifier circuit, and the circuit A2 is a drive inverter circuit. Further, an LC series body LC1 of an energy transfer capacitor Cr1 and an inductor Lr1 is connected between a connection point of the two MOSFETs 51 and 52 of the circuit A1 and a connection point of the two MOSFETs 53 and 54 of the circuit A2. .

  The MOSFETs 51 to 54 are power MOSFETs in which a parasitic diode is formed between the source and drain. The gate signals Gate1H, Gate1L, Gate2H, and Gate2L are output from the control circuit 31 to the gate terminals of the MOSFETs 51 to 54, respectively.

Next, the operation of the second DC / DC converter 25 will be described.
Here, the gate signals Gate1H, Gate1L, Gate2H, and Gate2L are ON / OFF signals having a duty ratio of 50%, the gate signals Gate1H and Gate2H are the same signal, and the gate signals Gate1L and Gate2L are the gate signals Gate1H and Gate2H. This is an inverted signal.

First, when the high-voltage side MOSFETs 52 and 54 are turned on by the gate signals Gate1H and Gate2H, a part of the energy stored in the smoothing capacitor Cs2 is transferred to the capacitor Cr1 because of a potential difference.
Next, when the high-voltage side MOSFETs 52 and 54 are turned off by the gate signals Gate1H and Gate2H and the low-voltage side MOSFETs 51 and 53 are turned on by the gate signals Gate1L and Gate2L, there is a potential difference, so that the voltage is stored in the capacitor Cr1. The energy is transferred to the smoothing capacitor Cs1.

  Thus, the energy stored in the smoothing capacitor Cs2 is transferred to the smoothing capacitor Cs1 by charging and discharging the capacitor Cr1. The voltage V1 input between the input voltage terminals VaH and VaL is output between the output voltage terminals VbH and VbL as a voltage V2 that has been stepped down by about 1/2. Since the input power of the voltage V1 is transferred as the power reduced to the voltage V2, the voltage V1 has a value larger than twice the voltage V2.

  If the gate signals Gate2H and Gate2L are turned on and the gate signals Gate1H and Gate1L are turned off, the MOSFETs 53 and 54 are turned on and the MOSFETs 51 and 52 are turned off. As a result, the input voltage terminal VaH and the output voltage terminal VbH become conductive, and the voltage V1 input between the input voltage terminals VaH and VaL becomes the voltage V2 that is stepped down by about 1 to obtain the output voltage terminals VbH and VbL. Output in between.

  Thus, the second DC / DC converter 25 can convert the input voltage V1 with a voltage exchange ratio N (V2 / V1) of 1 or 1/2 and output it.

  In addition, since the inductor Lr1 is connected in series to the capacitor Cr1 to form the LC series body LC1, the energy transfer uses the resonance phenomenon, and the transient loss when the state of the MOSFETs 51 to 54 changes. And a large amount of energy can be transferred efficiently. Thus, since it is excellent in terms of efficiency, a radiator for cooling the circuit can be made small. Moreover, since there is no transient loss at the time of switching of MOSFET51-54, a switching frequency can be set high. The resonance frequency of the LC series body LC1 can be increased, the inductance value of the energy transfer inductor Lr1 and the capacitance value of the capacitor Cr1 can be set small, and the circuit element can be miniaturized. Therefore, the entire second DC / DC converter 25 can be made very small.

  Next, a control method of the second DC / DC converter 25 in the low speed region will be described with reference to FIG. FIG. 5 is a diagram for explaining a control method of second DC / DC converter 25 in the low frequency range in the vehicle power supply system according to Embodiment 1 of the present invention.

  First, at step 100, the control circuit 31 monitors the rotational speed f of the engine 1 and determines whether the rotational speed f is less than a predetermined rotational speed (ThR). Here, the predetermined rotation speed (ThR) is a rotation speed near 1000 rpm, and corresponds to, for example, the rotation speed in the idling region.

If the rotational speed f is less than the predetermined rotational speed (ThR) in step 100, the process proceeds to step 101, where the remaining amount of the electric double layer capacitor 27 is sufficient based on the terminal voltage of the electric double layer capacitor 27. Determine whether or not.
In step 101, if the terminal voltage of the electric double layer capacitor 27 is equal to or lower than a predetermined voltage (ThC), the process proceeds to step 102, where the output voltage command value of the second DC / DC converter 25 is set to 14V (the rating of the battery 26). Voltage). Therefore, the control circuit 31 drives the second DC / DC converter 25, and the voltage of the high-voltage side wiring 34 becomes 14V.

  If the terminal voltage of the electric double layer capacitor 27 is greater than the predetermined voltage (ThC) in step 101, it is determined that there is still power that can be supplied to the rotating machine 9 via the inverter 28, and the process proceeds to step 103. In step 103, the output voltage command value of the second DC / DC converter 25 is set to 28V, and the process returns to step 101. Therefore, the control circuit 31 drives the second DC / DC converter 25, and the voltage of the high-voltage side wiring 34 becomes 28V. Here, the predetermined voltage (ThC) has only to be determined that power can be supplied to the rotating machine 9 via the inverter 28, and is set to the rated voltage (14V) of the battery 26, for example.

  Next, the operation of the vehicle power supply system in the low speed region will be described with reference to FIG. FIG. 6 is a diagram for explaining the operation in the low speed region of the vehicle power supply system according to Embodiment 1 of the present invention.

  In the first embodiment, when the control circuit 31 monitors the rotational speed f of the engine 1 and determines that the low speed range is reached in the decelerating state and the electric double layer capacitor 27 has sufficient remaining capacity, The output voltage command value of the second DC / DC converter 25 is maintained at 28V. That is, even in the idling region, the voltage exchange ratio N of the second DC / DC converter 25 is halved, and the voltage of the high-voltage side wiring 34 is held at 28V. Then, the control circuit 31 maintains the switching elements 32 and 33 in the ON state, and maintains a state in which the field current is supplied to the field windings 14 and 19.

  Then, as shown in FIG. 6B, even when the vehicle body decelerates and reaches the idling range, the voltage of the high-voltage side wiring 34 is maintained at 28V. The field current flowing in the field windings 14 and 19 connected to the high-voltage side wiring 34 is maintained at the maximum value as shown in FIG. Therefore, when the control circuit 31 receives an acceleration command during the idling state, the control circuit 31 drives the inverter 28, supplies AC power to the armature winding 13, and drives the rotating machine 9. At this time, since the maximum field current flows in the field winding 14, there is no response delay due to the time constant. As shown in FIG. 6D, the rotating machine 9 has only a response delay inherent to the rotating machine 9 and is driven quickly. As a result, the compressor 8 of the turbocharger 5 quickly reaches a sufficient rotational speed, and the rotational speed f of the engine 1 rises almost simultaneously with the acceleration command, as shown in FIG. Therefore, the vehicle body is accelerated rapidly according to the driver's accelerator operation, and the driver can feel the acceleration.

  Then, when the turbocharger 5 is operated and the rotational speed f of the engine 1 rises steeply and reaches the power generation possible rotational speed β of the generator 17, the generator 17 generates power. At this time, since the maximum field current flows in the field winding 19, there is no response delay due to the time constant, and when the rotational speed f reaches β, the generator 17 instantaneously outputs the output voltage of 28 V. To generate electricity. As a result, the combined output of the output of the generator 17 and the output of the electric double layer capacitor 27 via the second DC / DC converter 25 is converted into AC power by the inverter 28 and supplied to the rotating machine 9.

  Here, in the process of reaching the low speed range in the deceleration state of the vehicle body, the control circuit 31 monitors the terminal voltages of the battery 26 and the electric double layer capacitor 27 and regenerates energy as necessary. That is, when a capacity drop is detected from the terminal voltage of the battery 26 and the electric double layer capacitor 27, the generator 17 is driven to generate power. Then, the first and second DC / DC converters 24 and 25 are driven to store the generated power of the generator 17 in the battery 26 and the electric double layer capacitor 27.

  Next, the operation of the comparative example for switching the output voltage command value of the second DC / DC converter 25 to 14 V when the rotational speed f of the engine 1 is in the idling range will be described with reference to FIG. FIG. 7 is a diagram for explaining the operation in the low speed region of the vehicle power supply system of the comparative example.

  In this comparative example, when the vehicle body decelerates and reaches the idling range, the voltage of the high-voltage side wiring 34 decreases from 28 V to 14 V (rated voltage of the battery 26) as shown in FIG. Then, the field current flowing in the field windings 14 and 19 connected to the high-voltage side wiring 34 decreases as the rotational speed f decreases, as shown in FIG. , Maintained at a low value. Therefore, when the control circuit 31 receives an acceleration command during the idling state, the control circuit 31 controls the second DC / DC converter 25, boosts the voltage of the high-voltage side wiring 34 to 28V, drives the inverter 28, and supplies AC power to the electric machine. This is supplied to the child winding 13 to drive the rotating machine 9. At this time, the field current flowing through the field winding 14 has a response delay due to the time constant, as shown in FIG. The rotating machine 9 is driven with a delayed response due to a time constant, as shown in FIG. Accordingly, it takes time for the compressor 8 of the turbocharger 5 to reach a sufficient rotational speed, and the rotational speed f of the engine 1 rises with a delay from the acceleration command as shown in FIG.

  Then, when the turbocharger 5 operates, the rotational speed f of the engine 1 rises steeply, and reaches the power generation possible rotational speed β of the generator 17, the generator 17 instantaneously generates power with an output voltage of 28V.

  In this comparative example, the absolute value of the voltage applied to the field winding 14 is larger than the case where the voltage of the high-voltage side wiring 34 is maintained at 14 V at the time of acceleration command. Delay can be suppressed.

  In the first embodiment, the control circuit 31 monitors the voltage between the terminals of the field windings 14 and 19, and when the voltage between the terminals of the field windings 14 and 19 exceeds a threshold value, the control circuit 31 switches the switching elements 32 and 33. The field current supply to the field windings 14 and 19 is stopped. Thereby, the temperature of the field windings 14 and 19 can be kept below a predetermined temperature, and a burning accident of the field windings 14 and 19 can be avoided in advance.

  That is, since the output voltage command value of the second DC / DC converter 25 is set to 28V, the maximum field current flows through the field windings 14 and 19. And if energization to field windings 14 and 19 of field current continues, field windings 14 and 19 will generate heat, and temperature will rise. In the worst case, the field windings 14 and 19 are burned. The resistance values of the field windings 14 and 19 increase with increasing temperature. In addition, since the energization of the field windings 14 and 19 is controlled by constant current, the energization current becomes a constant value. From this, the temperature of the field windings 14 and 19 can be estimated from the voltage between the terminals of the field windings 14 and 19. Therefore, a threshold value of the voltage between the terminals of the field windings 14 and 19 is set, and the field current to the field windings 14 and 19 is set so that the voltage between the terminals of the field windings 14 and 19 does not exceed the threshold value. By controlling the energization, the temperature of the field windings 14 and 19 can be kept below a predetermined temperature.

  According to the first embodiment, one end of the field winding 19 of the generator 17 and one end of the field winding 14 of the rotating machine 9 of the turbocharger 5 are connected to the high-voltage side wiring 34, and the input of the inverter 28 is made. The terminal is connected to the high-voltage side wiring 34. When the vehicle body decelerates and the rotational speed f of the engine 1 decreases to a low speed range, the control circuit 31 controls the second DC / DC converter 25 to set the output voltage to 28V. Further, the control circuit 31 turns on the switching elements 32 and 33 and supplies a field current to the field windings 14 and 19.

  Therefore, when an acceleration command is received and AC power is supplied to the armature winding 13 via the inverter 28, an induced electromotive force is generated by the field winding 14, and the time constant of the field winding 14 is generated. There is no response delay due to. Further, since the electric double layer capacitor 27 can discharge a large current with high responsiveness, a large current is supplied from the electric double layer capacitor 27 to the inverter 28 via the high-voltage side wiring 34 in response to the acceleration command. As a result, the rotating machine 9 is driven quickly in response to the acceleration command, and the compressor 8 of the turbocharger 5 quickly reaches a sufficient number of revolutions. As a result, the vehicle body is accelerated rapidly in accordance with the driver's accelerator operation, and the driver can feel a sense of acceleration.

  Further, when the turbocharger 5 is operated and the rotational speed f of the engine 1 rises steeply and reaches the power generation possible rotational speed β of the generator 17, the generator 17 generates power. At this time, since the maximum field current flows in the field winding 19, there is no response delay due to the time constant, and when the rotational speed f reaches β, the generator 17 instantaneously outputs the output voltage of 28 V. To generate electricity. As a result, the combined output of the output of the generator 17 and the output of the electric double layer capacitor 27 via the second DC / DC converter 25 is converted into AC power by the inverter 28, and the armature winding 13 of the rotating machine 9 Supplied. Since a part of the large current supplied to the armature winding 13 is covered by the generated power of the generator 17, the power supply load of the electric double layer capacitor 27 and the second DC / DC converter 25 is reduced, and the electric double layer capacitor 27 Further, the second DC / DC converter 25 can be downsized.

  In the first embodiment, the rated voltage of the battery is 14V, and the first and second DC / DC converters having a voltage exchange ratio N of 1 or 1/2 are used. The high-voltage side wiring is held at 28 V, and the field current supplied to the field windings of the generator and the rotating machine becomes the maximum value. However, using the first and second DC / DC converters that can arbitrarily control the voltage exchange ratio N, the voltage of the high-voltage side wiring in the low speed region is held at the first voltage that is higher than the rated voltage of the battery, and the field current The current value may be lowered. In this case, the first voltage may be set so that the power generation start rotational speed of the generator using the first voltage as the output voltage is higher than the idling range.

  In the first embodiment, the first and second DC / DC converters having the voltage exchange ratio N of 1 or 1/2 are used. However, the voltage exchange ratio N of the first and second DC / DC converters is used. However, the first and second DC / DC converters having a voltage exchange ratio N of 1, 1/2, 1/3 may be used.

Embodiment 2. FIG.
FIG. 8 is a circuit configuration diagram of a vehicle power supply system according to Embodiment 2 of the present invention.

In FIG. 8, the input terminal of the inverter 28 is connected to the high voltage side terminal of the electric double layer capacitor 27, that is, the wiring between the electric double layer capacitor 27 and the output voltage terminal of the second DC / DC converter 25.
Other configurations are the same as those in the first embodiment.

In the second embodiment, a field current is applied to the field winding 14 prior to the acceleration command. When receiving an acceleration command, the control circuit 31 drives the inverter 28, and the output power of the electric double layer capacitor 27 is converted into AC power and supplied to the armature winding 13. Since the electric double layer capacitor 27 can discharge a large current with high responsiveness, the large current is supplied to the inverter 28 in response to the acceleration command, and the rotating machine 9 is driven quickly.
Therefore, also in the second embodiment, the driver can feel a sense of acceleration as in the first embodiment.

In the second embodiment, the high-voltage side wiring 34 is held at 28 V, and the field current is supplied to the field winding 19. When β, which is the number of revolutions that can be generated by the generator 17, is reached, the generator 17 instantaneously generates power, and a combined output of the output of the generator 17 and the output of the electric double layer capacitor 27 is supplied to the inverter 28. .
Therefore, also in the second embodiment, since a part of the large current supplied to the armature winding 13 is covered by the generated power of the generator 17, the electric double layer capacitor 27 and the second DC / DC converter 25 are small in size. Can be realized.

Embodiment 3 FIG.
FIG. 9 is a circuit configuration diagram of a vehicle power supply system according to Embodiment 3 of the present invention.

In FIG. 9, one end of the field winding 14 and the input terminal of the inverter 28 are connected to the high voltage side terminal of the electric double layer capacitor 27, that is, the wiring between the electric double layer capacitor 27 and the output voltage terminal of the second DC / DC converter 25. It is connected.
Other configurations are the same as those in the first embodiment.

In the third embodiment, a field current is applied to the field winding 14 prior to the acceleration command. When receiving an acceleration command, the control circuit 31 drives the inverter 28, and the output power of the electric double layer capacitor 27 is converted into AC power and supplied to the armature winding 13. Since the electric double layer capacitor 27 can discharge a large current with high responsiveness, the large current is supplied to the inverter 28 in response to the acceleration command, and the rotating machine 9 is driven quickly.
Therefore, also in the third embodiment, the driver can feel a sense of acceleration as in the first embodiment.

In the third embodiment, the high-voltage side wiring 34 is held at 28 V, and a field current is passed through the field winding 19. When β, which is the number of revolutions that can be generated by the generator 17, is reached, the generator 17 instantaneously generates power, and a combined output of the output of the generator 17 and the output of the electric double layer capacitor 27 is supplied to the inverter 28. .
Therefore, also in the third embodiment, part of the large current supplied to the armature winding 13 is covered by the generated power of the generator 17, so that the electric double layer capacitor 27 and the second DC / DC converter 25 can be reduced in size. Can be realized.

In each of the above embodiments, the rectifier is configured as a three-phase full-wave rectifier circuit using a diode bridge. However, the rectifier may be a MOSFET that performs synchronous rectification or a MOSFET that performs rectification using a parasitic diode. You may comprise with a polyphase inverter.
In each of the above embodiments, the stator of the generator uses a three-phase AC winding. However, the stator winding is not limited to a three-phase AC winding, but a three-phase AC winding. Or a multiphase AC winding (for example, 5 phase, 7 phase). In that case, the rectifier rectifies AC power into DC with a full-wave rectifier circuit according to the number of phases.

  1 Engine, 5 Turbocharger, 6 Turbine, 7 Rotating shaft, 8 Compressor, 9 Rotating machine, 14 Field winding, 15 Exhaust system, 16 Intake system, 17 Generator, 19 Field winding, 22 Rectifier, 22a High pressure Side output terminal, 24 1st DC / DC converter, 25 2nd DC / DC converter, 26 battery, 27 electric double layer capacitor, 28 inverter, 31 control circuit, 34 high voltage side wiring, 35 low voltage side wiring.

Claims (7)

A compressor disposed in the intake system of the engine for compressing the intake gas, a turbine attached coaxially to the rotation shaft of the compressor, disposed in the exhaust system of the engine and driven by the exhaust gas, and the rotation shaft A turbocharger having a rotating machine mounted coaxially;
An inverter that converts DC power into AC power and supplies the rotating machine;
A generator that is driven by the engine to generate AC power;
A rectifier that rectifies and outputs AC power generated by the generator to DC power;
A first DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier into a DC voltage of a different voltage value;
A battery connected to the first DC / DC converter via a low-voltage side wiring and supplying electric power to the vehicle-mounted load;
A second DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier to a DC voltage of a different voltage value;
An electric double layer capacitor connected to the second DC / DC converter;
The first DC / DC converter and the second DC / DC converter are drive-controlled to store the generated power of the generator in the battery and the electric double layer capacitor, and the inverter is driven to control the rotating machine. A control circuit for driving,
The inverter, the field winding of the rotating machine, and the field winding of the generator are connected to the high-voltage side wiring,
The control circuit drives and controls the second DC / DC converter so that the voltage of the high-voltage side wiring becomes a first voltage higher than the rated voltage of the battery when the engine speed is reduced to a predetermined speed by decelerating. And a power supply system for a vehicle, wherein the field winding of the generator and the field winding of the rotating machine are energized to maintain the state until reacceleration. A compressor disposed in the intake system of the engine for compressing the intake gas, a turbine attached coaxially to the rotation shaft of the compressor, disposed in the exhaust system of the engine and driven by the exhaust gas, and the rotation shaft A turbocharger having a rotating machine mounted coaxially;
An inverter that converts DC power into AC power and supplies the rotating machine;
A generator that is driven by the engine to generate AC power;
A rectifier that rectifies and outputs AC power generated by the generator to DC power;
A first DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier into a DC voltage of a different voltage value;
A battery connected to the first DC / DC converter via a low-voltage side wiring and supplying electric power to the vehicle-mounted load;
A second DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier to a DC voltage of a different voltage value;
An electric double layer capacitor connected to the second DC / DC converter;
The first DC / DC converter and the second DC / DC converter are drive-controlled to store the generated power of the generator in the battery and the electric double layer capacitor, and the inverter is driven to control the rotating machine. A control circuit for driving,
The inverter is connected to the high voltage side terminal of the electric double layer capacitor;
The field winding of the rotating machine and the field winding of the generator are connected to the high-voltage side wiring,
The control circuit drives and controls the second DC / DC converter so that the voltage of the high-voltage side wiring becomes a first voltage higher than the rated voltage of the battery when the engine speed is reduced to a predetermined speed by decelerating. And a power supply system for a vehicle, wherein the field winding of the generator and the field winding of the rotating machine are energized to maintain the state until reacceleration. A compressor disposed in the intake system of the engine for compressing the intake gas, a turbine attached coaxially to the rotation shaft of the compressor, disposed in the exhaust system of the engine and driven by the exhaust gas, and the rotation shaft A turbocharger having a rotating machine mounted coaxially;
An inverter that converts DC power into AC power and supplies the rotating machine;
A generator that is driven by the engine to generate AC power;
A rectifier that rectifies and outputs AC power generated by the generator to DC power;
A first DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier into a DC voltage of a different voltage value;
A battery connected to the first DC / DC converter via a low-voltage side wiring and supplying electric power to the vehicle-mounted load;
A second DC / DC converter connected to the high-voltage side output terminal of the rectifier via a high-voltage side wiring and converting the output voltage of the rectifier to a DC voltage of a different voltage value;
An electric double layer capacitor connected to the second DC / DC converter;
The first DC / DC converter and the second DC / DC converter are drive-controlled to store the generated power of the generator in the battery and the electric double layer capacitor, and the inverter is driven to control the rotating machine. A control circuit for driving,
The inverter and the field winding of the rotating machine are connected to the high voltage side terminal of the electric double layer capacitor,
The field winding of the generator is connected to the high-voltage side wiring,
The control circuit drives and controls the second DC / DC converter so that the voltage of the high-voltage side wiring becomes a first voltage higher than the rated voltage of the battery when the engine speed is reduced to a predetermined speed by decelerating. And a power supply system for a vehicle, wherein the field winding of the generator and the field winding of the rotating machine are energized to maintain the state until reacceleration.   The vehicle power supply system according to any one of claims 1 to 3, wherein the predetermined rotation speed is approximately 1000 rpm.   5. The vehicle power supply system according to claim 1, wherein a power generation start rotational speed of the generator using the first voltage as an output voltage is higher than an idling range. 6.   The control circuit performs ON / OFF control of energization of the field winding of the rotating machine and the field winding of the generator, so that the field winding of the rotating machine and the field of the generator are controlled. The vehicle power supply system according to any one of claims 1 to 5, wherein the temperature of the winding is controlled.   The control circuit applies the field winding of the rotating machine and the field winding of the rotating machine and the field winding of the generator based on the voltage across the terminals of the field winding of the generator. The vehicle power supply system according to claim 6, wherein energization is ON / OFF controlled.

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