JP6619979B2 - Charge control device - Google Patents

Description

  The present invention relates to a charge control device that performs charge control on a battery mounted on a vehicle.

  Conventionally, electric power generated by an in-vehicle generator is charged to an in-vehicle battery. For example, a vehicle is known that generates electric power (hereinafter also referred to as “decelerated regenerative power generation”) using the kinetic energy of the vehicle when the vehicle is braked, and the battery can charge the generated electric power. In addition, a technique has also been proposed in which power is generated by a Rankine cycle that collects waste heat generated in a vehicle and converts it into motive power (hereinafter also referred to as “waste heat regenerative power generation”), and the generated power is charged in a battery. .

  For example, Patent Document 1 discloses a power supply control device mounted on a vehicle that includes both an alternator & regulator that performs power generation using engine power and deceleration regenerative power generation, and a waste heat regenerative generator that performs waste heat regenerative power generation. It is disclosed. Such a power supply control device is a power supply bus to which waste heat regenerative power and deceleration regenerative power are supplied, and the waste heat power generation control means is disposed of when the deceleration regenerative power is supplied to the power supply bus by the deceleration regenerative means. Reduces heat regenerative power. Specifically, the power supply control device sets the adjustment voltage for the waste heat regenerative power generation to a value higher than the adjustment voltage value for the power generation and to the decelerating regenerative power generation when the deceleration regenerative power is supplied to the power supply bus. Control is performed so that the value is lower than the adjustment voltage.

JP 2007-154800 A

  Here, in the power supply control device described in Patent Document 1, the waste heat regenerative power voltage is made smaller than the deceleration regenerative power voltage while the deceleration regenerative power is generated. It will be in the state which is not supplied to. Therefore, the power supply control device described in Patent Document 1 charges both the deceleration regenerative power and the waste heat regenerative power even if the sum of the deceleration regenerative power and the waste heat regenerative power is less than the charge output capacity of the battery. Despite the capacity to recycle, waste heat regenerative power could not be charged. On the other hand, the deceleration regenerative power uses the kinetic energy at the time of braking of the vehicle and cannot store the kinetic energy, so the sum of the deceleration regenerative power and the waste heat regenerative power is the battery charge output capacity. In this case, it is desirable to charge the deceleration regenerative power with priority over the waste heat regenerative power.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to reduce the regenerative power and waste heat regenerative power according to the charge output capacity of the battery during the deceleration regenerative power generation of the vehicle. It is an object of the present invention to provide a new and improved charge control device that can appropriately charge a battery of a battery.

In order to solve the above-described problem, according to an aspect of the present invention, a decelerating regenerative power detection unit that detects first charging power by a decelerating regenerative generator that collects kinetic energy of a vehicle and generates power when the vehicle decelerates. A waste heat regenerative power detection unit that detects a second charge power by a waste heat regenerative generator that collects waste heat from the internal combustion engine of the vehicle and generates power; and a first charge power and a second charge power When the sum is less than the charge output capacity of the battery, the output voltage of the second charge power is matched with the output voltage of the first charge power and greater than the output voltage of the battery , and the first charge power and Control where the output voltage of the second charging power is smaller than the output voltage of the first charging power and smaller than the output voltage of the battery when the sum of the second charging power is equal to or greater than the charging output capacity of the battery A charging control device comprising: It is provided.

  The waste heat power generation control unit may reduce the output voltage of the second charging power to be lower than the output voltage of the battery when the sum of the first charging power and the second charging power is greater than or equal to the charging output capacity of the battery. Good.

  When the sum of the first charging power and the second charging power is greater than or equal to the charging output capacity of the battery, the waste heat is generated after the output voltage of the second charging power is made smaller than the output voltage of the first charging power. You may provide the bypass control part which bypasses at least one part of the working medium introduced into the expander which generate | occur | produces the driving force of a regenerative generator.

  The bypass control unit may control the opening degree of the bypass valve provided in the bypass passage that communicates the upstream side and the downstream side of the expander based on the rotation speed of the expander or the pressure in the expander.

  The bypass control unit may maintain the rotation of the inflator.

  As described above, according to the present invention, while deceleration regenerative power generation is performed during braking of the vehicle, charging of the battery with deceleration regenerative power and waste heat regenerative power is appropriately performed according to the charge output capacity of the battery. It becomes possible to carry out.

1 is a schematic diagram illustrating an example of a schematic configuration of a vehicle charging system according to an embodiment of the present invention. It is a block diagram which shows an example of a function structure of the control apparatus concerning the embodiment. It is explanatory drawing which shows the charging / discharging electric power of a high voltage battery. It is explanatory drawing which shows the relationship between the rotation speed of an expander, and the opening degree of a bypass valve. It is a flowchart which shows the charge control method concerning the embodiment. It is a time chart which shows charge control in case there exists a charge capacity of a high voltage battery. It is a time chart which shows charge control in case there is no charge capacity of a high voltage battery.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Overall configuration of charging system>
First, the overall configuration of the vehicle charging system according to the present embodiment will be described. FIG. 1 is a schematic diagram illustrating an example of a configuration of a charging system 10 according to the present embodiment. The illustrated charging system 10 is an example of the charging system 10 including a Rankine cycle power generation system 70 in a parallel hybrid vehicle. However, the vehicle charging system according to this embodiment may be a series type hybrid vehicle provided with a Rankine cycle power generation system, or a series parallel type hybrid vehicle provided with a Rankine cycle power generation system. There may be.

  As shown in FIG. 1, the charging system 10 includes an engine 14, a cooling water flow path 16, a driving force transmission system 18, driving wheels 22, a high voltage battery 30, a motor generator 40, and Rankine cycle power generation. The system 70 and the charging control apparatus 100 are provided.

(engine)
The engine 14 is an engine that generates a driving force of a vehicle such as a gasoline engine or a diesel engine, and the generated driving force is transmitted to the driving wheels 22 via the driving force transmission system 18. The engine 14 is driven or stopped according to the traveling state of the vehicle. Further, the output torque of the engine 14 is variably controlled according to the required torque of the vehicle by an engine control device (not shown). The engine 14 includes a cooling water circulation passage 15 that passes through a cooling water passage 16 disposed outside the engine 14 via the cylinder block and the cylinder head. The cooling water circulating in the cooling water circulation passage 15 collects waste heat generated by combustion in the cylinders of the engine 14 when passing through the inside of the engine 14. The cooling water flow path 16 provided outside the engine 14 is connected to a heat exchanger 78 of the Rankine cycle power generation system 70, and the cooling water that has recovered waste heat in the engine 14 passes through the heat exchanger 78. In the meantime, heat exchange with the working medium of the Rankine cycle power generation system 70 is performed.

(High voltage battery)
The high voltage battery 30 is a high voltage (for example, 200V) power supply source. Specifically, the high voltage battery 30 supplies power to the motor / generator 40 that outputs the driving force of the vehicle. The high voltage battery 30 may supply power to a low voltage battery that supplies power to various devices in the vehicle via a step-down converter. The high voltage battery 30 can store the power generated by the waste heat regenerative generator 60 and the power generated by the motor / generator 40, respectively. The high voltage battery 30 includes a voltage sensor and a temperature sensor (not shown). The voltage sensor detects the terminal voltage of the high voltage battery 30 and transmits a sensor signal to the charging control device 100. For example, the temperature sensor detects a cell temperature of the high voltage battery 30 and transmits a sensor signal to the charging control device 100.

(Motor generator)
The motor / generator 40 has both a function as a driving motor that generates a driving force of the vehicle and a function as a generator that generates electric power using the kinetic energy of the vehicle. The motor / generator 40 includes, for example, a three-phase AC motor and an inverter device, and is electrically connected to the high voltage battery 30 via the inverter device. The inverter device is driven by the charge control device 100. The inverter device of the motor / generator 40 functions as an inverter and a converter.

  When the motor / generator 40 functions as a driving motor, the charging control device 100 controls the inverter of the inverter device, converts DC power supplied from the high voltage battery 30 into AC power, and supplies the AC power to the motor. As a result, the motor rotates and a driving force is generated. Further, the charging control device 100 controls the inverter device, and variably controls the output torque of the motor according to the required torque of the vehicle. The driving force generated by the motor / generator 40 is transmitted to the driving wheels 22 via the driving force transmission system 18. Further, when the motor / generator 40 functions as a generator, the charging control device 100 controls the converter of the inverter device, converts the AC power generated by the motor rotated by the rotation of the drive wheels 22 into DC power, and increases the power. The voltage battery 30 is supplied. Thereby, resistance is given to rotation of the drive wheel 22, and braking force is generated. The electric power generated by the motor / generator 40 is stored in the high voltage battery 30.

(Driving force transmission system)
The driving force transmission system 18 includes a clutch device, a transmission, a differential gear, and the like, and transmits the driving force transmitted from the engine 14 and the motor / generator 40 to the driving wheels. The driving force transmission system 18 transmits the rotational force of the driving wheels 22 to the motor / generator 40 when the vehicle is decelerated. Various mechanisms constituting the driving force transmission system 18 are not particularly limited.

(Rankine cycle power generation system)
The Rankine cycle power generation system 70 uses the waste heat of the engine 14 to generate power. Specifically, the Rankine cycle power generation system 70 generates mechanical energy using the waste heat of the engine 14, and drives the waste heat regenerative generator 60 with the generated mechanical energy to generate waste heat regenerative power. . As shown in FIG. 1, the Rankine cycle power generation system 70 includes a working medium flow path 72, a Rankine cycle pump 74, a heat exchanger 78, an expander 86, a waste heat regenerative generator 60, and a condenser 90. And a reservoir 98, a bypass channel 82, and a bypass valve 94.

  The reservoir 98 stores the liquefied working medium. As the working medium, for example, water, chlorofluorocarbon or alcohol is used. The working medium is sucked up and pumped by the Rankine cycle pump 74. The working medium flows through the working medium flow path 72, and returns to the reservoir 98 through the heat exchanger 78, the expander 86, and the condenser 90. The Rankine cycle pump 74 can be, for example, an electric pump that is driven and controlled by the charge control device 100. The charge control device 100 variably controls the discharge amount of the Rankine cycle pump 74.

  The working medium channel 72 and the cooling water channel 16 are connected to the heat exchanger 78. In the heat exchanger 78, heat exchange is performed between the working medium flowing in the working medium flow path 72 and the cooling water flowing in the cooling water flow path 16. As a result, the working medium is heated and vaporized by the waste heat of the engine 14 recovered by the cooling water.

  The expander 86 expands the working medium vaporized by the heat exchanger 78 to generate mechanical energy. For example, the expander 86 includes an expansion chamber, an impeller (turbine) disposed in the expansion chamber, and an output shaft connected to the impeller. The vaporized working medium that has flowed into the expander 86 further expands in the expansion chamber, and the impeller receives the flow of the working medium to generate rotational energy of the impeller. The expander 86 is connected to the waste heat regenerative generator 60, and the rotational energy of the impeller is output as power of the waste heat regenerative generator 60 via the output shaft. The rotational speed Nt of the expander 86 can be detected by the rotational speed sensor 62. The rotational speed sensor 62 is provided, for example, in the vicinity of the output shaft of the expander 86 or the rotational shaft of the rotor of the waste heat regenerative generator 60. The detected rotation speed Nt of the expander 86 is transmitted to the charging control device 100.

  The waste heat regenerative generator 60 includes, for example, a three-phase AC motor and an inverter device, and is electrically connected to the high voltage battery 30 via the inverter device. The inverter device of the waste heat regenerative generator 60 functions as a converter and is driven by the charge control device 100. The waste heat regenerative generator 60 generates power using rotational energy output through the output shaft of the expander 86 as power. For example, the rotor of the waste heat regenerative generator 60 is connected to the output shaft of the expander 86, and power is generated by rotating the rotor as the impeller rotates. The charging control device 100 controls the converter of the inverter device, converts the generated AC power into DC power, and supplies it to the high voltage battery 30. The electric power generated by the waste heat regenerative generator 60 is stored in the high voltage battery 30.

  The bypass channel 82 communicates the upstream side and the downstream side of the expander 86 in the working medium channel 72, and bypasses the working medium vaporized by the heat exchanger 78 without passing through the expander 86. Road. The bypass passage 82 is provided with a bypass valve 94 that can open and close the bypass passage 82. The bypass valve 94 is configured by, for example, an electromagnetic valve. The electromagnetic valve may be an on / off valve capable of switching the opening and closing of the bypass passage 82, or may be a proportional control valve capable of adjusting the opening degree of the bypass passage 82. The bypass valve 94 is driven and controlled by the charge control device 100. When the bypass valve 94 is opened, at least a part of the working medium vaporized by the heat exchanger 78 is caused to bypass the expander 86 and flow downstream according to the opening degree of the bypass valve 94. Thereby, the driving force output from the expander 86 is adjusted.

  The condenser 90 cools, using a refrigerant, the vapor-phase working medium that has passed through the expander 86 or the vapor-phase working medium that bypasses the expander 86, condenses it, and liquefies it. The working medium liquefied by the condenser 90 returns to the reservoir 98.

  The charging control device 100 is mainly configured to include a CPU (Central Processing Unit) that is an arithmetic processing device. In addition to the CPU, the charging control device 100 stores a ROM (Read Only Memory) that stores programs used by the CPU, calculation parameters, and the like, a program used in the execution of the CPU, and a parameter that changes as appropriate in the execution. RAM (Random Access Memory) etc. which temporarily store are provided.

  The charging control device 100 controls the operation of each device constituting the charging system 10. Specifically, the charging control device 100 issues an operation instruction to each device to be controlled using an electrical signal. In the charging system 10 according to the present embodiment, the charge control device 100 controls driving of the Rankine cycle pump 74, the bypass valve 94, the inverter device of the motor / generator 40, and the inverter device of the waste heat regenerative generator 60. Moreover, the charging control apparatus 100 receives the sensor signal output from each sensor. The charging control apparatus 100 may acquire information detected by each sensor via CAN (Controller Area Network) communication.

  1 is configured by a single control device, the charge control device 100 may be configured by a plurality of control devices. In this case, the plurality of control devices may be connected to each other via a communication bus such as CAN.

<2. Configuration of control device>
Next, the configuration of the charge control device 100 according to the present embodiment will be described. FIG. 2 is a block diagram illustrating an example of the configuration of the charge control device 100 according to the present embodiment. The charge control device 100 includes a deceleration regenerative power detection unit 110, a waste heat regenerative power detection unit 120, a charge output capacity detection unit 130, a power comparison unit 140, and a motor / generator control unit (M / G control unit) 150. And a waste heat power generation control unit 160 and a bypass control unit 170.

(Deceleration regenerative power detector)
The deceleration regenerative power detection unit 110 detects the value of the first charging power (decelerated regenerative power) Wmg generated by the motor / generator 40. For example, the decelerating regenerative power detection unit 110 is generated by the motor / generator 40 based on the voltage value Vmg detected by the voltage sensor provided in the inverter device of the motor / generator 40 and the current value Amg detected by the current sensor. The decelerated regenerative power Wmg is detected.

(Waste heat regenerative power detector)
The waste heat regenerative power detection unit 120 detects the value of the second charging power (waste heat regenerative power) Wrc generated by the waste heat regenerative generator 60. For example, the waste heat regenerative power detection unit 120 uses the waste heat regenerative power generation based on the voltage value Vrc detected by the voltage sensor provided in the inverter device of the waste heat regenerative generator 60 and the current value Arc detected by the current sensor. The waste heat regenerative power Wrc generated by the machine 60 is detected.

(Charge output capacity detector)
The charge output capacity detection unit 130 detects the charge output capacity Win of the high voltage battery 30. The charge output capacity Win of the high-voltage battery 30 is a value of power set according to the free capacity of the battery 4 as power required for charging at the start of charging. For example, the charge output capacity detection unit 130 determines the high voltage battery 30 based on the battery temperature Tb, the charge rate SOC (State Of Charge) of the high voltage battery 30, and the deterioration degree SOH (State Of Health) of the high voltage battery 30. The charge output capacity Win is detected.

  FIG. 3 is an explanatory diagram showing the relationship between the battery temperature Tb, the charging rate SOC of the high voltage battery 30, and the charge / discharge power of the high voltage battery 30. The solid line shows the charge / discharge power characteristics when the charge rate SOC is high, and the broken line shows the charge / discharge power characteristics when the charge rate SOC is low. As shown in FIG. 3, the higher the charging rate SOC of the high-voltage battery 30, the higher the discharge power and the smaller the charge power (charge output capacity). If the charge rate SOC does not change, both the discharge power and the charge power (charge output capacity) gradually increase as the battery temperature Tb increases, and reach a certain value when the temperature exceeds a certain temperature. And if battery temperature Tb becomes remarkably high, both discharge electric power and charging electric power (charging output capacity) will become zero. Although not shown in FIG. 3, as the deterioration degree SOH of the high-voltage battery 30 increases, both the discharge power and the charge power (charge output capacity) decrease.

  As the battery temperature Tb, a cell temperature detected by a temperature sensor provided in the high voltage battery 30 can be used. The charging rate SOC and the deterioration degree SOH can be detected by, for example, a state sensor provided in the high voltage battery 30. The charge output capacity detection unit 130 detects a cell temperature Tb detected by a temperature sensor provided in the high voltage battery 30. Note that the method for detecting the charge output capacity Win is not limited to this example.

(Power comparison part)
The power comparison unit 140 performs a predetermined comparison operation using the deceleration regenerative power Wmg, the waste heat regenerative power Wrc, and the charge output capacity Win of the high voltage battery 30. Specifically, the power comparison unit 140 compares the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc with the charge output capacity Win of the high voltage battery 30. Then, the power comparison unit 140 determines whether the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is greater than or equal to the charge output capacity Win of the high voltage battery 30.

(M / G control unit)
The M / G control unit 150 controls the inverter device of the motor / generator 40 to generate a driving force by the motor / generator 40 or to generate a deceleration regenerative power Wmg. The charging system 10 according to the present embodiment is applied to a parallel hybrid system, and the M / G control unit 150 generates driving force by the motor / generator 40 when the vehicle travels, During braking, the motor / generator 40 performs deceleration regenerative power generation using the kinetic energy of the vehicle. When generating the deceleration regenerative electric power Wmg, the M / G control unit 150 decelerates the output voltage Vin of the high voltage battery 30 by using a predetermined voltage, for example, a voltage value of 5%, as a target value. The output voltage Vmg of the regenerative power Wmg is controlled.

(Waste heat power generation control unit)
The waste heat power generation control unit 160 generates waste heat regenerative power Wrc by using the waste heat of the engine 14 by the Rankine cycle power generation system 70. Specifically, the waste heat power generation control unit 160 generates the waste heat regenerative power Wrc by controlling the Rankine cycle pump 74 and the inverter device of the waste heat regenerative generator 60. When the waste heat power generation control unit 160 generates the waste heat regenerative power Wrc, a target voltage is obtained by adding a predetermined voltage, for example, a voltage corresponding to 5%, to the output voltage Vin of the high voltage battery 30. The output voltage Vrc of the waste heat regenerative power Wrc is controlled. Further, the waste heat power generation control unit 160 controls the output voltage Vrc of the waste heat regenerative power Wrc based on the comparison result by the power comparison unit 140 while the deceleration regenerative power generation is performed.

  Specifically, the waste heat power generation control unit 160, based on the comparison result of the power comparison unit 140, when the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is less than the charge output capacity Win of the high voltage battery 30. The output voltage Vrc of the waste heat regenerative power Wrc is made to coincide with the output voltage Vmg of the deceleration regenerative power Wmg. For example, the M / G control unit 150 and the waste heat power generation control unit 160 control the output voltages Vmg and Vrc of the generated power by adding the same voltage to the output voltage Vin of the high voltage battery 30, respectively. In this case, both the M / G control unit 150 and the waste heat power generation control unit 160 continue the control.

  Further, the M / G control unit 150 and the waste heat power generation control unit 160 control the output voltages Vmg and Vrc of the generated power by adding different voltages to the output voltage Vin of the high voltage battery 30, respectively. In this case, the waste heat power generation control unit 160 matches the added voltage value with the value added by the M / G control unit 150. Or the M / G control part 150 and the waste heat power generation control part 160 may each change the voltage value to add to the predetermined predetermined value set beforehand. Thereby, when the chargeable capacity of the high voltage battery 30 has a margin, both the deceleration regenerative power Wmg and the waste heat regenerative power Wrc can be charged to the high voltage battery 30.

  Further, the waste heat power generation control unit 160 discards the waste heat generation power when the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is greater than or equal to the charge output capacity Win of the high voltage battery 30 based on the comparison result of the power comparison unit 140. The output voltage Vrc of the thermal regenerative power Wrc is made smaller than the output voltage Vmg of the deceleration regenerative power Wmg. For example, the waste heat power generation control unit 160 sets the voltage Vrc of the waste heat regenerative power Wrc as a target value by subtracting a predetermined voltage, for example, 10% of the voltage from the output voltage Vin of the high voltage battery 30. Control. Thereby, when the chargeable capacity of the high-voltage battery 30 has no allowance, the deceleration regenerative power Wmg is preferentially charged over the waste heat regenerative power Wrc.

(Bypass control unit)
The bypass control unit 170 performs drive control of the bypass valve 94 and performs control for bypassing the expander 86 with the working medium. Specifically, the bypass control unit 170 determines the rotation speed when the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is greater than or equal to the charge output capacity Win of the high-voltage battery 30 based on the comparison result of the power comparison unit 140. Based on the rotational speed Nt of the expander 86 detected by the sensor 62, drive control of the bypass valve 94 is performed. The bypass control of the working medium by the bypass controller 170 is performed in order to prevent seizure due to excessive rotation of the expander 86.

  Specifically, as described above, when the deceleration regenerative power generation is started and the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is greater than or equal to the charge output capacity Win of the high voltage battery 30, the waste heat regenerative power Wrc. Output voltage Vrc is made smaller than the output voltage Vmg of the deceleration regenerative power Wmg, the waste heat regenerative power Wrc is not charged to the high voltage battery 30. Therefore, the load (resistance) of the impeller of the expander 86 is lost, and the rotation speed of the expander 86 can be increased rapidly. In order to prevent such over-rotation of the expander 86, the bypass controller 170 causes the expander 86 to bypass at least a part of the working medium.

  FIG. 4 is an explanatory diagram showing an example of the relationship between the rotational speed Nt of the expander 86 and the opening degree of the bypass valve 94. As illustrated in FIG. 4, the bypass control unit 170 may control the bypass valve 94 such that the opening degree of the bypass valve 94 increases as the rotation speed Nt of the expander 86 increases. If the bypass valve 94 is a proportional control valve, the opening degree of the bypass valve 94 can be proportionally controlled. However, when the bypass valve 94 is an on / off valve, a threshold value for opening the bypass valve 94 A threshold value for closing may be set, and the bypass valve 94 may be opened and closed based on the rotation speed Nt of the expander 86.

  However, if the rotation of the expander 86 is completely stopped, the decelerating regenerative power generation is completed, and when the charging of the waste heat regenerative power Wrc is resumed, a delay may occur and the power generation efficiency may be reduced. Therefore, in the charge control device 100 according to the present embodiment, the opening degree of the bypass valve 94 is controlled so that the rotation speed Nt of the expander 86 is maintained below a predetermined target value.

  The bypass controller 170 may control the opening degree of the bypass valve 94 based on the vapor pressure in the expander 86 instead of the rotation speed Nt of the expander 86. The vapor pressure can be detected, for example, by providing a pressure sensor in the expansion chamber of the expander 86. In this case, the opening degree of the bypass valve 94 can be controlled so that the vapor pressure in the expander 86 is maintained in a range in which seizure due to excessive rotation of the expander 86 does not occur.

<3. Flow chart>
Next, the flow of processing performed by the charging control apparatus 100 according to the present embodiment will be described. FIG. 5 is a flowchart showing a flow of processing performed by the charging control apparatus 100. Such a flowchart may be executed all the time after the key switch of the vehicle is turned on, for example.

  First, after the key switch of the vehicle is turned on, the charging control device 100 controls the Rankine cycle power generation system 70 and starts waste heat regenerative power generation using the waste heat of the engine 14. For example, the waste heat power generation control unit 160 drives the Rankine cycle pump 74 to circulate the working medium in the working medium flow path 72. At this time, the bypass valve 94 is closed. When the working medium passes through the heat exchanger 78, the working medium is heated by the amount of heat of the cooling water from which the waste heat of the engine 14 is recovered, is vaporized, and then flows into the expander 86. The vaporized working medium is further expanded in the expander 86 to rotate the impeller (turbine).

  The output shaft connected to the impeller is connected to the waste heat regenerator 60, and the rotational energy of the impeller is transmitted as power to the waste heat regenerator 60, whereby the waste heat regenerator 60 is Driven. The waste heat power generation control unit 160 drives and controls the inverter device of the waste heat regenerative generator 60, converts AC power generated by the waste heat regenerative generator 60 into DC power, and supplies the DC power to the high voltage battery 30. At this time, the output voltage Vrc of the waste heat regenerative power Wrc is controlled using a voltage value added by a predetermined pressure as compared with the charge output capacity Win of the high voltage battery 30 as a target value. Thereby, the waste heat regenerative power Wrc generated using the waste heat of the engine 14 is charged to the high voltage battery 30.

  Next, in step S20, the charging control apparatus 100 determines whether deceleration regenerative power generation has been started. For example, the deceleration regenerative power detection unit 110 determines whether or not the deceleration regenerative power generation is started based on whether or not the control of the motor / generator 40 is switched from the driving force output control to the charge control by the M / G control unit 150. can do. Until the deceleration regenerative power generation is started (S20: No), the process returns to step S10 and the waste heat regenerative power generation is continued.

  On the other hand, when the deceleration regeneration power generation is started (S20: Yes), in step S30, the charging control device 100 detects the deceleration regeneration power Wmg, the waste heat regeneration power Wrc, and the charge output capacity Win. For example, the deceleration regenerative power detection unit 110 detects the deceleration regenerative power Wmg based on the sensor signals of the voltage sensor and the current sensor provided in the inverter device of the motor / generator 40. Further, the waste heat regenerative power detection unit 120 detects the waste heat regenerative power Wrc based on the sensor signals of the voltage sensor and current sensor provided in the inverter device of the waste heat regenerative generator 60. Further, the charging output capacity detection unit 130 detects the charging output capacity Win of the high voltage battery 30 based on the battery temperature Tb, the charging rate SOC, the deterioration degree SOH, and the like of the high voltage battery 30.

  Next, in step S40, the power comparison unit 140 of the charging control apparatus 100 determines whether or not the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is less than the charge output capacity Win of the high voltage battery 30. . When the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is less than the charge output capacity Win of the high voltage battery 30 (S40: Yes), in step S50, the charge control device 100 outputs the waste heat regenerative power Wrc. The voltage Vrc and the output voltage Vmg of the deceleration regenerative power Wmg are matched to continue the deceleration regenerative power generation and the waste heat regenerative power generation. The target values of the output voltages Vmg and Vrc at this time are not particularly limited as long as they are larger than the output voltage Vin of the high voltage battery 30. Thereby, when the chargeable capacity of the high voltage battery 30 has a margin, both the deceleration regenerative power Vmg and the waste heat regenerative power Vrc are charged to the high voltage battery 30.

  On the other hand, when the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is greater than or equal to the charge output capacity Win of the high voltage battery 30 (S40: No), in step S60, the charge control device 100 determines that the waste heat regenerative power Wrc. Is set to a value smaller than the output voltage Vmg of the deceleration regenerative power Wmg. The target value of the output voltage Vrc at this time is not particularly limited as long as it is a value smaller than the output voltage Vin of the high-voltage battery 30. For example, the target value of the output voltage Vin of the high-voltage battery 30 is −10% be able to. As a result, the waste heat regenerative power Wrc is not charged to the high voltage battery 30, and the deceleration regenerative power Wmg is preferentially charged to the high voltage battery 30.

  Next, in step S <b> 70, the charge control device 100 controls the opening degree of the bypass valve 94 and performs control for allowing at least a part of the working medium to pass through the expander 86. For example, the bypass controller 170 controls the opening degree of the bypass valve 94 so that the rotational speed Nt detected by the rotational speed sensor 62 that detects the rotational speed of the expander 86 is maintained below a predetermined target value. To do. The target value of the rotational speed Nt can be appropriately set to a value in a range in which the seizure of the expander 86 does not occur. The bypass control unit 170 may control the rotation speed Nt of the expander 86 to be equal to or less than the target value while adjusting the opening degree of the bypass valve 94 with reference to, for example, a control map shown in FIG.

  Alternatively, the bypass control unit 170 may control the rotation speed Nt of the expander 86 to be equal to or less than the target value while switching between opening and closing of the bypass valve 94. Thereby, even when the waste heat regenerative power Wrc is no longer charged and the load (resistance) of the waste heat regenerative generator 60 is lost, it is possible to prevent seizure due to over-rotation of the expander 86. Even if the waste heat regenerative power generation is not performed, the rotation of the expander 86 is maintained, so that the waste heat regenerative power generation can be restarted promptly after the deceleration regenerative power generation is completed.

  After the output voltage Vrc of the waste heat regenerative power Vrc is determined in step S50 or step S60, respectively, in step S80, the charge control device 100 determines whether or not the deceleration regenerative power generation is completed. Similar to step S20, for example, the deceleration regenerative power detection unit 110 ends the deceleration regenerative power generation depending on whether or not the control of the motor / generator 40 is switched from the charge control to the driving force output control by the M / G control unit 150. It can be determined whether or not.

  If the deceleration regenerative power generation continues (S80: No), the charging control apparatus 100 returns to step S40 and repeats the steps after step S40. On the other hand, if the deceleration regenerative power generation has been completed (S80: Yes), the charging control apparatus 100 returns to step S10 and repeats the steps after step S10.

<4. Time chart>
Next, an example of transition of the output voltage Vrc of the waste heat regenerative generator 60 and the opening degree of the bypass valve 94 when processing by the charging control apparatus 100 according to the present embodiment is performed will be described based on a time chart.

  FIG. 6 is a time chart when there is a margin in the chargeable capacity of the high voltage battery 30 at the start of the deceleration regenerative power generation. In this case, even if the deceleration regenerative power generation is started at time t1, the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is less than the charge output capacity Win of the high voltage battery 30, and the waste heat regenerative power Wrc The output voltage Vrc is maintained at or above the output voltage Vin of the high voltage battery 30. The value of the output voltage Vrc of the waste heat regenerative power Wrc matches the value of the output voltage Vmg of the deceleration regenerative power Wmg.

  As a result, the rotation speed and the steam pressure of the expander 86 are maintained and the waste heat regenerative power generation continues from the time t1 at which the deceleration regenerative power generation is started to the time t2 at which it is ended. During this time, the bypass valve 94 is not fully opened and is kept fully closed. That is, when the chargeable capacity of the high voltage battery 30 has a margin, both the deceleration regenerative power Wmg and the waste heat regenerative power Wrc are charged to the high voltage battery 30 even during the deceleration regenerative power generation.

  FIG. 7 is a time chart when there is no room for the chargeable capacity of the high voltage battery 30 at the start of the deceleration regenerative power generation. In this case, when the deceleration regenerative power generation is started at time t11, the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc becomes equal to or greater than the charge output capacity Win of the high voltage battery 30, and the output voltage of the waste heat regenerative power Wrc. Vrc is set to a value smaller than the output voltage Vmg of the deceleration regenerative power Wmg. As a result, the deceleration regenerative power Vmg is charged in the high voltage battery 30, while the waste heat regenerative power Wrc is not charged in the high voltage battery 30.

  In this case, after the deceleration regenerative power generation is started, the opening degree of the bypass valve 94 is controlled, and at least a part of the working medium bypasses the expander 86, and the rotation speed or the vapor pressure of the expander 86 is expanded. It is maintained in a range where no seizure due to over-rotation of the vessel 86 occurs. Thereafter, when the deceleration regenerative power generation ends at time t12, the output voltage Vrc of the waste heat regenerative power Wrc is returned to the original setting. Further, after time t2, the control of the opening degree of the bypass valve 94 is finished, and the bypass valve 94 is fully closed. As a result, the rotational speed Nt of the expander 86 increases, and the charging of the waste heat regenerative power Wrc to the high voltage battery 30 is resumed.

<5. Summary>
As described above, according to the charging control apparatus 100 according to the present embodiment, when the deceleration regenerative power generation is started, the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is charged to the high voltage battery 30. When the output capacity is greater than or equal to the output capacity Win, the output voltage Vrc of the waste heat regenerative power Wrc is made smaller than the output voltage Vmg of the deceleration regenerative power Wmg. Thereby, charging of the deceleration regenerative electric power Wmg is performed preferentially. At this time, the opening degree of the bypass valve 94 is controlled, and at least a part of the working medium bypasses the expander 86, and seizure due to excessive rotation of the expander 86 is prevented.

  Further, according to the charging control apparatus 100 according to the present embodiment, when the deceleration regenerative power generation is started, the sum of the deceleration regenerative power Wmg and the waste heat regenerative power Wrc is less than the charge output capacity Win of the high voltage battery 30. In this case, the output voltage Vrc of the waste heat regenerative power Wrc and the output voltage Vmg of the decelerating regenerative power Wmg are matched, and power generation is continued. Thereby, the deceleration regenerative power Wmg and the waste heat regenerative power Wrc are both charged. Therefore, according to the charging control apparatus 100 according to the present embodiment, the deceleration regenerative power Wmg and the waste heat are generated according to the charge output capacity Win of the high voltage battery 30 while the deceleration regenerative power generation is performed during braking of the vehicle. Charging the high voltage battery 30 with the regenerative power Wrc can be performed appropriately.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that those having ordinary knowledge in the technical field to which the present invention pertains can make various modifications or application examples within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  For example, in the above embodiment, the example of the control for charging the high-voltage battery 30 has been described, but the technology according to the present invention is not limited to such an example. For example, the battery to be charged may be a low voltage (for example, 40 V) battery that supplies power to various devices in the vehicle. In such a case, the motor generator in the above embodiment may be replaced with an alternator. As a result, while the deceleration regenerative power generation is performed during braking of the vehicle, the low voltage battery is appropriately charged with the deceleration regenerative power Wmg and the waste heat regenerative power Wrc in accordance with the charge output capacity of the low voltage battery. can do.

  Further, the processes described using the flowcharts in the above-described embodiments do not necessarily have to be executed in the order shown in the flowcharts. Additional processing steps may be employed.

DESCRIPTION OF SYMBOLS 10 Charging system 30 High voltage battery 40 Motor generator 60 Waste heat regeneration generator 70 Rankine cycle power generation system 74 Rankine cycle pump 78 Heat exchanger 82 Bypass flow path 86 Inflator 90 Condenser 94 Bypass valve 100 Charge control device 110 Deceleration regeneration Power detection unit 120 Waste heat regenerative power detection unit 130 Charging output capacity detection unit 140 Power comparison unit 150 M / G control unit 160 Waste heat power generation control unit 170 Bypass control unit

Claims (4)

A decelerating regenerative power detection unit for detecting a first charging power by a decelerating regenerative generator that collects kinetic energy of the vehicle and generates power when the vehicle decelerates;
A waste heat regenerative power detector that detects second charge power by a waste heat regenerative generator that recovers waste heat of the internal combustion engine of the vehicle and generates power;
When the sum of the first charging power and the second charging power is less than the charging output capacity of the battery, the output voltage of the second charging power is the output voltage of the first charging power, and When the sum of the first charging power and the second charging power is equal to or greater than the charging output capacity of the battery, the output voltage of the second charging power is set to the voltage value larger than the output voltage. A waste heat power generation control unit having a voltage value smaller than the output voltage of the charging power and smaller than the output voltage of the battery ;
A charge control device. When the sum of the first charging power and the second charging power is greater than or equal to the charging output capacity of the battery, the output voltage of the second charging power is made smaller than the output voltage of the first charging power. The charging control device according to claim 1 , further comprising a bypass control unit that bypasses at least a part of the working medium introduced into the expander that generates the driving force of the waste heat regenerative generator. The bypass control unit controls an opening degree of a bypass valve provided in a bypass passage communicating the upstream side and the downstream side of the expander based on the rotation speed of the expander or the pressure in the expander. The charge control device according to claim 2 . The charge control device according to claim 2 , wherein the bypass control unit maintains rotation of the expander.

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