JP6238079B2 - Rotating electric machine and engine starting system - Google Patents

Description

  The present invention relates to a rotating electrical machine and an engine start system for stopping an engine.

  Conventionally, an example of a technique related to a startability predicting apparatus for the purpose of accurately predicting whether or not an in-vehicle battery can start an engine has been disclosed (see, for example, Patent Document 1). This startability predicting device is configured to measure the voltage value and the current value of the in-vehicle battery when the in-vehicle battery is not being charged. Further, the voltage value of the in-vehicle battery is calculated when the starting current value at the start of the engine is applied to the voltage-current characteristic of the in-vehicle battery, and the engine is started when it is determined that the calculated voltage value is lower than the first voltage value. Predict that it is impossible.

JP 2008-230433 A

  Even if the technique of Patent Document 1 is applied, the following problems remain. First, there is a high possibility that the voltage value or current value of the in-vehicle battery measured without energizing the starter (electric motor) does not match the voltage value or current value of the in-vehicle battery measured with energization of the starter. Even when the starter is energized, if an electric current is passed through the field winding of the starter, an output torque is generated, which may cause the engine to operate (rotate) carelessly.

  Second, based on the data at the time of the previous restart, it is determined whether or not the battery is in a state where the engine can be restarted next time. There is a time interval between the previous restart and the next restart, and the state of the in-vehicle battery changes in accordance with the operating condition of the engine included in the interval. If the battery state changes greatly, the estimation error becomes large even if the voltage-current characteristic of the on-vehicle battery is applied.

  The present invention has been made in view of such a point, and a first object is to make it possible to determine whether or not the engine can be restarted so that the engine is not inadvertently operated. The second object is to improve the accuracy of determination as to whether or not the engine can be restarted as compared with the prior art.

The first invention made to solve the above-mentioned problems is mechanically connected to the engine (23), and includes a stator winding (Lu, Lv, Lw) and a field winding (Lf). In the rotating electrical machine (17) having the rotating electrical machine main body (17b), when a start condition that requires operation of the stopped engine is satisfied, a start signal is transmitted from the external device (EX), and the battery (19) A start control unit (17a) that controls the operation of the rotating electrical machine main body to start the engine by causing current to flow through the stator winding and the field winding , and operation is unnecessary stop condition is satisfied in the engine, the stop request signal from an external device (SA) is transmitted without passing a current (If) to the field winding, said stator winding from said battery Passing a current (Is), the voltage value measured by the voltage sensor for measuring voltage of the battery (Vd) is a voltage threshold (Vth) or more, and measured by a current sensor for measuring a current flowing in the stator winding Startability determination means (172) for determining whether or not the battery can supply electric power necessary for the next start of the engine based on whether or not the current value (Is) to be performed is equal to or greater than the current threshold (Ith ). And a stop permission signal for permitting the external device to stop the engine in order to stop the engine when it is determined by the start possibility determination means that power necessary for starting the engine next time can be supplied. Signal output means (171) for outputting (SB).

According to this configuration, the startability determination unit measures the battery voltage and the current flowing through the stator winding when the stop condition is satisfied (particularly immediately before the engine is stopped). It is determined whether or not the battery can supply electric power necessary for starting the next engine based on whether or not the measured voltage value is equal to or greater than the voltage threshold value and the current value is equal to or greater than the current threshold value. Since this determination is not affected by the operating condition of the engine until the engine is stopped, the determination accuracy can be improved as compared with the conventional case. Further, since no current is passed through the field winding, current is passed through the stator winding, so that no output torque is generated in the rotating electrical machine. Therefore, it is possible to prevent the engine from operating carelessly.

  According to a second aspect of the present invention, when it is determined by the startability determination means that the electric power necessary for starting the engine cannot be supplied, the start control unit operates the engine without stopping the engine. The charging control means (173) further performs control for charging the battery with the electric power generated by the rotating electrical machine until the signal output means satisfies a charging termination condition for terminating the charging of the battery. After the battery is charged by the charge control means, the stop permission signal is output.

  According to this configuration, even when the stop condition is satisfied, the charging control unit performs power generation by forcibly continuing the operation of the engine to charge the battery. Further, charging is performed until the charging termination condition is satisfied by the charging control means. Therefore, since it is sufficiently considered that the battery capacity (also referred to as power capacity or storage capacity; hereinafter the same) is recovered by charging the battery, the engine can be started more reliably and the determination accuracy is improved.

  According to a third aspect of the present invention, when the charge control means determines that the electric power necessary for starting the engine cannot be supplied by the start possibility determination means, the charge control means is based on a voltage value measured by the voltage sensor. One or both of the time and the charging current amount is changed.

  According to this configuration, since the charging time and the amount of charging current are made variable according to the state of the battery, the time from when the stop condition is satisfied until the engine is stopped can be optimized (minimized). In addition, it is possible to minimize the frequency of determination by the startability determination unit and suppress wasteful power consumption.

The fourth invention is stopped mechanically with the rotating machine (51), which is mechanically connected to the engine (23) and includes stator windings (Lu, Lv, Lw) and field windings (Lf) . When a start condition necessary for operation of the engine is satisfied, a start signal is transmitted from an external device (EX), and current is passed from the battery (19) to the stator winding and the field winding, respectively. A start control unit (50) for controlling the rotating electric machine to start, and when the stop condition that does not require operation of the engine is satisfied, the engine is stopped and the operation of the stopped engine is required starting satisfy an engine starting system for starting the engine (10 and 10B, 10C) in the starting control unit, said a stop condition is satisfied, stop from the external device Request signal (SA) is transmitted measured without passing a current (If) to the field winding, a current flows (Is) from said battery to said stator winding, the voltage sensor for measuring voltage of said battery Whether or not a voltage value (Vd) to be measured is equal to or greater than a voltage threshold value (Vth) and a current value (Is) measured by a current sensor that measures a current flowing through the stator winding is equal to or greater than a current threshold value (Ith) in said battery is started possibility determining means for determining whether or not capable of supplying electric power required to start the next of said engine (50b), the power required to start the next of said engine by said starter possibility determining means The engine stop means (50a) for stopping the engine when it is determined that the engine can be supplied.

According to this configuration, the startability determination unit measures the battery voltage and the current flowing through the stator winding when the stop condition is satisfied (particularly immediately before the engine is stopped). It is determined whether or not the battery can supply electric power necessary for starting the next engine based on whether or not the measured voltage value is equal to or greater than the voltage threshold value and the measured current value is equal to or greater than the current threshold value. Since this determination is not affected by the operating condition of the engine until the engine is stopped, the determination accuracy can be improved as compared with the conventional case. Further, since no current is passed through the field winding, current is passed through the stator winding, so that no output torque is generated in the rotating electrical machine. Therefore, it is possible to prevent the engine from operating carelessly.

  The “battery” may be of any type or number as long as it can be charged (storage) and supplied (discharged). A battery that can be charged and supplied may be combined with a battery that can only be supplied without being charged. The “rotary electric machine” is a device that operates (functions) as at least an electric motor to start the engine, and is preferably a device that also operates as a generator. The “stop condition” may be arbitrarily set as long as it does not require engine operation and is a condition for stopping the engine. The “starting condition” may be arbitrarily set as long as it is necessary to operate the engine and is a condition for starting the engine. “Startup” includes restart. “Charging time” is the time (period) from the start to the end of charging the battery. The “charge current amount” is an integrated amount of current that flows from the start to the end of charging the battery (also called “charge capacity”, the unit is ampere-hour [Ah]). Various “signals” are arbitrary and may be analog signals, digital signals, data, or the like.

It is a mimetic diagram showing the 1st example of composition of an engine starting system. It is a schematic diagram which shows the 1st structural example of a rotary electric machine. It is a schematic diagram which shows the structural example of a power conversion means. It is a flowchart figure which shows the example of a procedure of a starting control process. It is a flowchart figure which shows the example of a procedure of a charge control process. It is a graph which shows the relationship between a voltage value, charging time, and charging current amount. It is a time chart which shows a time-dependent change, such as a voltage, an electric current, and rotation speed. It is a schematic diagram which shows the 2nd structural example of an engine starting system. It is a schematic diagram which shows the 3rd structural example of an engine starting system. It is a schematic diagram which shows the structural example of a starting control part. It is a schematic diagram which shows the 4th structural example of an engine starting system. It is a schematic diagram which shows the 2nd structural example of a rotary electric machine. It is a schematic diagram which shows the 5th structural example of an engine starting system.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Note that unless otherwise specified, “connecting” means electrically connecting. Each figure shows elements necessary for explaining the present invention, and does not necessarily show all actual elements. When referring to directions such as up, down, left and right, the description in the drawings is used as a reference. The engine starting systems 10A, 10B, and 10C shown in the embodiments are all examples of the engine starting system 10, and correspond to any case where the reference numeral “10” is simply shown in the drawings. Alphanumeric continuous codes are abbreviated using the symbol “˜”. For example, the “engine start systems 10A, 10B, and 10C” are abbreviated as “engine start systems 10A to 10C”.

[Embodiment 1]
The first embodiment will be described with reference to FIGS. A vehicle 100 shown in FIG. 1 is a configuration example of a hybrid vehicle. The vehicle 100 includes batteries 11, 19, 20, an electric load 12, a converter 13, wheels 14, a transmission 15, a rotary electric machine 16, 17, a power transmission member 18, 22, an inverter 21, an engine 23, a power conversion control device 24, and the like. Have Among these elements, the engine start system 10A includes at least the rotating electrical machine 17 and the voltage sensor 30 (see FIG. 2).

  The battery 11 is a power source that supplies power to the second power line CL, and is a power source that is separate from the battery 19. The battery 19 is a power source that supplies power when starting the engine 23 or supplies power to the second power line CL via the switch unit SW3. The battery 20 is a power source that supplies power to the third power line HL via the switch unit SW1. The batteries 11, 19, and 20 are of any type as long as they can store and discharge, and for example, secondary batteries such as lithium ion batteries and lead storage batteries are applicable. In this embodiment, a storage battery (for example, a lead storage battery) is used for the batteries 11 and 19, and a lithium ion battery is used for the battery 20.

  The first power line PL, the second power line CL, and the third power line HL are all power transmission paths and may include a relay connector. A switch unit SW2 is interposed between the second power line CL and the first power line PL. The switch unit SW2 corresponds to a “separation switch”. The voltage (for example, 12 volts) of the first power line PL and the second power line CL in this embodiment is lower than the third power line HL (for example, 660 volts).

  The electrical load 12 is a component, member, or the like that is supplied through the second power line CL to operate. For example, a meter, a car navigation system, lamps (for example, a headlight, a room light, a taillight, etc.), an air conditioner (an air conditioner, a heater, etc.), a motor that operates a member such as a wiper, and the like are applicable. The converter 13 converts a voltage between the second power line CL and the third power line HL. The inverter 21 converts the power supplied from the battery 20 and supplies it to the rotating electrical machine 16 (functions as an electric motor), or converts the power supplied from the rotating electrical machine 16 (functions as a generator) and charges the battery 20 To do. The converter 13 and the inverter 21 operate based on signals individually transmitted from the power conversion control device 24 as indicated by broken lines.

The rotating electrical machine 17 is included in the engine start system 10A as described above, and is mechanically connected to the engine 23 by the power transmission member 18. The rotating electrical machine 17 has both functions of an electric motor and a generator. When starting the engine 23, when assisting the motive power of the engine 23, in a case of determining the starting potential below that battery 19, to function as an electric motor. In the case of receiving power from the engine 23 and the wheels 14, it functions as a generator. A configuration example of the rotating electrical machine 17 will be described later (see FIG. 2).

  The power transmission member 18 may be an arbitrary member as long as it can be mechanically connected to the engine 23 and can start the engine 23 or generate power. For example, one or more of a shaft (rotary shaft), a cam, a link, a crank, a belt, a gear, a rack and pinion, and the like are applicable.

  The power source of the vehicle 100 is the engine 23 and the rotating electrical machine 16. The engine 23 may be of any type as long as it is an internal combustion engine. The rotating electrical machine 16 is mechanically connected to the engine 23 by a power transmission member 22 and has functions of an electric motor and a generator. Power generated in one or both of the engine 23 and the rotating electrical machine 16 is transmitted to the wheel 14 via the transmission 15 and the power transmission member 22. Thus, the vehicle 100 travels by transmitting power to the wheels 14. The transmission 15 may be manual or automatic.

  The rotating electrical machine 16 when operating as a power source receives electric power supplied from the battery 20 via the inverter 21 and functions as an electric motor. When the rotating electrical machine 16 receives power from the power transmission member 18, it functions as a generator. Examples of receiving power from the power transmission member 18 include, for example, the case where the engine 23 is operated, and the case where the vehicle 100 travels (for example, coasting or downhill travel) without requiring power. .

  The rotating electrical machine 17 illustrated in FIG. 2 includes a start control unit 17a, a rotating electrical machine main body unit 17b, and the like. The start control unit 17 a is configured to be able to transmit a signal to and from the external device EX, and performs control for operating the rotating electrical machine main body unit 17 b mainly to start the engine 23. The external device EX corresponds to, for example, an ECU (Electronic Control Unit) or a computer. The rotating electrical machine main body 17b includes stator windings Lu, Lv, Lw, a field winding Lf, and the like (see FIG. 3).

  The start control unit 17a receives electric power supplied from the battery 19 and controls the current required for starting the engine 23 to flow through the field winding Lf (see FIG. 3), and before stopping the engine 23. Control for securing electric power necessary for the next start of the engine 23 is performed. The start control unit 17a shown in FIG. 2 includes a signal output unit 171, a start possibility determination unit 172, a charge control unit 173, a power conversion control unit 174, and the like.

  The startability determination unit 172 determines whether or not electric power necessary for starting the engine 23 can be supplied when a stop condition that does not require the operation of the engine 23 is satisfied. That is, it is determined whether or not starting is possible. When it is determined that the engine can be started, the determination result signal SC is transmitted to the signal output means 171. When it is determined that starting is impossible, after charging request signal SD is transmitted to charge control means 173 in order to charge battery 19, it waits until it receives charge completion signal SE from charge control means 173, and charge completion signal SE. Then, the possibility of starting is determined again. In other words, when it is determined that starting is impossible, control is performed to charge the battery 19 until it is determined that starting is possible.

  In determining the startability, the startability determination means 172 transmits a determination command signal SF to the power conversion control means 174. The power conversion control means 174 that has received the determination command signal SF performs power conversion, and does not cause the field current If to flow through the field winding Lf of the rotating electrical machine main body 17b (that is, If = 0), and the stator winding. A stator current Is is passed through the lines Lu, Lv, and Lw (see also FIGS. 3, 6, and 7). The field current If and the stator current Is correspond to the determination current SH. Then, the startability determination means 172 is based on the voltage value Vd of the battery 19 measured by the voltage sensor 30 and the current value (stator current Is shown in FIG. 3) measured by the current sensor 31. Determine. A specific example of determining the possibility of starting will be described later (see FIGS. 4 and 6).

  The charging control unit 173 continues the operation of the engine 23 without stopping the engine 23 and performs control for charging the battery 19 with the electric power generated by the rotating electrical machine 17. Charging of the battery 19 is performed when the charge control means 173 receives a charge request signal SD transmitted by the startability determination means 172 determining that start is impossible. The charge control means 173 that has received the charge request signal SD transmits a charge command signal SG to the power conversion control means 174.

  The power conversion control means 174 performs power conversion. In this embodiment, when the power conversion control means 174 receives the determination command signal SF, it performs control to convert the power supplied from the battery 19 via the first power line PL and output it to the rotating electrical machine main body 17b. As described above, the field current If is not supplied to the field winding Lf, but the stator current Is is supplied to the stator windings Lu, Lv, Lw. Further, when the power conversion control means 174 receives the charge command signal SG, it performs control to convert the electromotive force EF (that is, power) generated in the rotating electrical machine main body 17b and charge the battery 19. A configuration example of the power conversion control unit 174 will be described later (see FIG. 3).

  When the start possibility determination unit 172 receives the determination result signal SC, the signal output unit 171 outputs a stop permission signal SB for permitting the external device EX to stop the engine 23. Receiving the stop permission signal SB, the external device EX performs control for stopping the engine 23 (for example, stopping fuel supply).

  The power conversion control means 174 shown in FIG. 3 includes an inverter control unit 174a, an inverter 174b, and the like. The inverter control unit 174a performs a plurality of switching operations included in the inverter 174b based on various signals such as the determination command signal SF transmitted from the startability determination unit 172 and the charge command signal SG transmitted from the charge control unit 173. Controls the operation of elements Q1-Q6, Qf.

  Inverter 174b includes switching elements Q1 to Q6 and Qf, diodes D1 to D6 and Df, and the like. As the switching elements Q1 to Q6 and Qf, any semiconductor element capable of switching operation can be applied. For example, an FET (specifically, MOSFET, JFET, MESFET, etc.), IGBT, GTO, power transistor, or the like is applicable. In this embodiment, IGBT is applied. These switching elements Q1 to Q6 and Qf are all turned on / off in accordance with signals individually transmitted from inverter control unit 174a. The diodes D1 to D6 and Df are connected in parallel between the collector terminal and the emitter terminal of the corresponding switching element. These diodes D1 to D6 all function as freewheeling diodes. Switching elements Q1-Q3, diodes D1-D3, etc. are arranged on the upper arm side, and switching elements Q4-Q6, diodes D4-D6, etc. are arranged on the lower arm side. The common potential G is a potential (ground) that is at least common in the inverter 174b. The common potential G when grounding is 0 [V].

  The circuit elements in the inverter 174b are connected in parallel in three phases (in this example, the U phase, the V phase, and the W phase) as surrounded by a one-dot chain line, and the operation is controlled for each phase by the inverter control unit 174a. The U phase is composed of switching elements Q1, Q4, diodes D1, D4, and the like. The V phase includes switching elements Q2 and Q5, diodes D2 and D5, and the like. The W phase includes switching elements Q3 and Q6, diodes D3 and D6, and the like. The U-phase switching elements Q1 and Q4 are connected in series to form a half bridge. Similarly, the V-phase switching elements Q2 and Q5 and the W-phase switching elements Q3 and Q6 are connected in series to form a half bridge. Each connection point of the half bridge and the stator windings Lu, Lv, Lw of the inverter 174b are connected by lines Ku, Kv, Kw, respectively. When the switching elements Q1, Q4 are driven, the U-phase current Iu flows through the stator winding Lu via the line Ku. When switching elements Q2 and Q5 are driven, V-phase current Iv flows through stator winding Lv via line Kv. When switching elements Q3 and Q6 are driven, W-phase current Iw flows through stator winding Lw via line Kw. The U-phase current Iu, the V-phase current Iv, and the W-phase current Iw are measured by the current sensor 31 as the stator current Is.

  The circuit element in the inverter 174b has a switching element Qf connected in parallel to the above-described three phases. Switching element Qf is connected in series with field winding Lf of rotating electrical machine main body 17b. The current flowing through the field winding Lf is measured by the current sensor 32 as the field current If.

FIG. 3 shows the rotating electrical machine main body 17b in which the stator windings Lu, Lv, Lw are Y-connected. The connection form is not limited to the Y connection, and may be changed according to the type or rating of the rotating electrical machine main body 17b. Although not shown, the stator windings Lu, Lv, and Lw may be Δ-connected, or Y-Δ connections that combine Y-connection and Δ-connection.

  A start control process repeatedly executed in the rotating electrical machine 17 configured as described above will be described with reference to FIG. Step S19 in FIG. 4 corresponds to the signal output means 171. Steps S11, S14, and S15 correspond to startability determination means 172 (including power conversion control means 174). Step S22 (charging control process in FIG. 5) corresponds to charging control means 173 (including power conversion control means 174). It is assumed that the engine 23 is in operation and the separation switch (switch unit SW2) is turned on before executing the start control process. The start controller 17a performs on / off control of the separation switch.

  In the starting control process of FIG. 4, it is first determined whether or not a stop condition for stopping the engine 23 is satisfied [step S10]. In this embodiment, the determination is made based on whether or not the stop request signal SA is received from the external device EX. Wait until a stop request signal SA is received (NO in step S10). In other words, the processing after step S11 is not executed.

  When the stop request signal SA is received (YES in step S10), the switching element Qf is turned off in accordance with the transmission of the determination command signal SF to stop energization of the field winding Lf [step S11]. When the energization of the field winding Lf is stopped, the field current If decreases and finally stops flowing (that is, If = 0). Therefore, the process waits until the field current If flowing through the field winding Lf reaches 0 [A] (NO in step S12).

  When field current If does not flow in field winding Lf (YES in step S12), the separation switch is turned off [step S13], and switching elements Q1-Q6 are driven in accordance with the transmission of determination command signal SF, and the stator is driven. Energization of the windings Lu, Lv, Lw is started [step S14]. At this time, the rotating electrical machine main body 17b operates as an electric motor. When energization of the stator windings Lu, Lv, and Lw is started, the phase currents Iu, Iv, and Iw flow, and the voltage value Vd that is the terminal voltage of the battery 19 changes (usually decreases).

  Therefore, startability is determined based on the voltage value Vd measured by the voltage sensor 30 and the stator current Is measured by the current sensor 31 [step S15]. The determination method of the startability may be arbitrarily set. In this embodiment, when the stator current Is is maintained at the current threshold value Ith or more (Is ≧ Ith) and the voltage value Vd is maintained at the voltage threshold value Vth or more (Vd ≧ Vth) within the determination period, the start is performed. Judge that it is possible. On the other hand, when the stator current Is is lower than the current threshold value Ith (Is <Ith) or when the voltage value Vd is lower than the voltage threshold value Vth (Vd <Vth), it is determined that starting is impossible.

  If the determination made in step S15 can be started (YES in step S16), electric power necessary for starting the engine 23 can be supplied from the battery 19. Therefore, the switching elements Q1 to Q6 are turned off [step S17] and the separation switch is turned on [step S18] in order to stop energization to the stator windings Lu, Lv, and Lw performed for the determination. Since preparation for stopping the engine 23 is thus completed, the stop permission signal SB is transmitted to the external device EX based on the determination result signal SC. The external device EX that has received the stop permission signal SB performs control for stopping the engine 23.

  On the other hand, if the determination made in step S15 is not startable (NO in step S16), charging is performed to increase the charge capacity of the battery 19 (steps S20 to S22). Specifically, as in step S17, energization of the stator windings Lu, Lv, Lw is stopped [step S20], the separation switch is turned on [step S21], and the charge control process is executed [step S22. ].

  In the charging control process shown in FIG. 5, the charging time CT and the charging current amount CV are changed based on the voltage value Vd and the stator current Is measured during the determination period [step S30]. The charging time CT is a period during which charging is performed, and is the amount of current that flows the charging current amount CV to the battery 19 during charging. The charging time CT may be set (including changes; the same applies hereinafter), the charging current amount CV may be set, or both the charging time CT and the charging current amount CV may be set. Step S30 may be executed or may not be executed. If not, the charging time CT and the charging current amount CV are set to respective predetermined constant values.

  An example of changing the charging time CT and the charging current amount CV is shown in FIG. FIG. 6 shows characteristic lines L1 and L2 when the left vertical axis is the charging time CT, the right vertical axis is the charging current amount CV, and the horizontal axis is the voltage value Vd. Normally, as the voltage value Vd increases, the charging capacity (remaining amount) of the battery 19 increases, so the charging time CT and the charging current amount CV may be reduced. Conversely, as the voltage value Vd decreases, the charging capacity of the battery 19 decreases, and therefore it is necessary to increase the charging time CT and the charging current amount CV. A characteristic line L1 indicated by a solid line is defined in a curved line, and a characteristic line L2 indicated by a one-dot chain line is defined in a curved line. The relationship between the voltage value Vd and the charging time CT may be defined by the characteristic line L1 or may be defined by the characteristic line L2. Similarly, the relationship between the voltage value Vd and the charging current amount CV may be defined by the characteristic line L1 or may be defined by the characteristic line L2. If the voltage value Vd is determined, the charging time CT and the charging current amount CV are also determined based on the characteristic lines L1 and L2.

  Instead of the voltage value Vd, a stator current Is shown in parentheses in FIG. 6 may be used, or a power value Ps (= Vd × Is) may be used. Two or more of the voltage value Vd, the stator current Is, and the power value Ps may be used. In the case of using two or more, a plurality of charging times CT and charging current amounts CV are determined, so one value may be selected or a simple average, a weighted average or the like may be obtained.

  Returning to FIG. 5, after setting the charging time CT and the charging current amount CV, charging is started based on the charging request signal SD and the charging command signal SG [step S31]. Specifically, the power of the engine 23 that has not been stopped is used. That is, based on the power transmitted from the engine 23 through the power transmission member 18, the rotating electrical machine main body 17b is caused to function as a generator. The electromotive force EF generated in the rotating electrical machine main body 17b is transmitted to the battery 19 through the power conversion control means 174 and the first power line PL and charged (see FIGS. 1 and 2).

  The charging in step S31 is continued until the charging end condition is satisfied (NO in step S32). The charging end condition may be arbitrarily set as long as the charging is completed, and includes a charging time CT and a charging current amount CV. If the charging termination condition is satisfied (YES in step S32), the charging is terminated based on the charging completion signal SE and the charging command signal SG [step S33], and the charging control process is terminated (returned).

  FIG. 7 shows a control example (including a change example) by the above-described rotating electrical machine 17 (specifically, the start control unit 17a shown in FIGS. 2 and 3). The horizontal axis is time t. On the vertical axis, in order from the top, stop condition satisfaction flag FL, switch part SW2 (separation switch), stator current Is, field current If, voltage value Vd, and an example of changes over time of engine 23 with respect to time Show. It is assumed that the engine 23 is operating before time t1.

  When the stop request signal SA is received from the external device EX at time t1, the stop condition is satisfied (YES in step S10 in FIG. 4), so the stop condition establishment flag FL is changed from low (indicated as “L” in FIG. 7) to high (FIG. 7). 7 indicates “H”). When the stop condition satisfaction flag FL becomes high, the energization to the rotating electrical machine main body 17b is stopped, and at least until the field current If reaches 0 [A] (step S12 in FIG. 4). In the example of FIG. 7, the field current If that was the current value If1 at time t1 reaches 0 [A] at time t2. The stator current Is is 0 [A] from the current value Is2 during energization. The period from time t1 to time t2 is not always constant.

  Since the field current If has reached 0 [A] at time t2, the switch unit SW2 is switched from on to off (step S13 in FIG. 4), and the battery 19 stores the power necessary for the next start of the engine 23. Whether or not there is is determined (step S15 in FIG. 4). For example, in the check section Chk1 from time t2 to time t3, the determination is made based on whether the stator current Is can maintain the current threshold Ith or less and the voltage value Vd can maintain the voltage threshold Vth or more.

  In the example of change indicated by the solid line in FIG. 7, the stator current Is could be maintained at the current value Is1 that is equal to or less than the current threshold Ith (Ith> Is1). However, as the switch unit SW2 is turned off, the voltage value Vd of the battery 19 decreases from the voltage value Vd3 to the voltage value Vd2, and further decreases to a voltage value Vd1 that is lower than the voltage threshold Vth after the check section Chk1 has elapsed. Vd3> Vd2> Vth> Vd1). Although the voltage value Vd can be maintained at the voltage threshold value Vth or more as in the example of change indicated by the two-dot chain line in FIG. 7, the stator current Is is below the current threshold value Ith. The same applies to the case where the voltage value Vd is lower than the voltage threshold value Vth and the stator current Is is lower than the current threshold value Ith. In any case, it is determined that the engine cannot be started in step S15 shown in FIG. Therefore, at time t3, the energization to the stator current Is is stopped and the stator current Is is set to 0 [A].

  Since it is determined that the engine cannot be started, the switch unit SW2 is switched from OFF to ON (step S21 in FIG. 4), and after the time t3, the operation of the engine 23 is not stopped and the rotating electrical machine main body unit 17b is used as a generator. The battery 19 is charged by functioning. That is, the rotational speed R of the engine 23 is maintained at a rotational speed exceeding 0 [rpm] (usually equal to or higher than the idling rotational speed). Therefore, the rotational speed R does not always become a constant rotational speed as shown by a two-dot chain line. In the control example of FIG. 7, the charging time CT is specified from the characteristic line L1 shown in FIG. 6 based on the voltage value Vd at the time t3, and the charging current amount CV (current value Is3 in FIG. 7) from the characteristic line L2. Is identified. Therefore, the battery 19 is charged while securing the current value Is3 corresponding to the charging current amount CV from time t3 to time t4 when the charging section CS corresponding to the charging time CT (ie, CS = CT) elapses. Due to the generation of the electromotive force EF, the current value If2 flows in the field current If in the variation of FIG. If the current value Is3 cannot be ensured, charging may be performed with the maximum current that can be secured by the electromotive force EF of the rotating electrical machine main body 17b.

  Since the charging termination condition is satisfied at time t4 when the charging section CS elapses, the charging of the battery 19 is terminated (steps S32 and S33 in FIG. 5). Subsequently, the energization of the rotating electrical machine main body 17b is stopped again, and the process waits at least until the field current If reaches 0 [A] (step S12 in FIG. 4). In the example of FIG. 7, the field current If reaches 0 [A] at time t5. Then, it is determined again whether or not the battery 19 stores the electric power necessary for starting the engine 23 (step S15 in FIG. 4). The determination method is the same as that of the check section Chk1 described above.

  In the check section Chk2 from time t5 to time t6, the determination is made based on whether or not the stator current Is can maintain the current threshold Ith or less and the voltage value Vd can maintain the voltage threshold Vth or more. In the example of change indicated by the solid line in FIG. 7, the stator current Is could be maintained at the current value Is1 that is equal to or less than the current threshold Ith (Ith> Is1). Further, the voltage value Vd of the battery 19 decreases from the voltage value Vd7 at the time of charging to the voltage value Vd6 as the switch unit SW2 is turned off, and further decreases to the voltage value Vd5 at the time t6 when the check section Chk2 elapses. The voltage threshold value Vth or more could be secured (Vd7> Vd6> Vd5> Vth). Therefore, in step S15 shown in FIG. Therefore, the stop permission signal SB is transmitted to the external device EX at time t6 (step S19 in FIG. 4). The external device EX receives the stop permission signal SB and performs control to stop the engine 23, and the rotational speed R becomes 0 [rpm] at time t7. After time t7 when the engine 23 is stopped, the stop condition satisfaction flag FL is set to low.

  Although not shown, if the stator current Is cannot be maintained below the current threshold Ith and the voltage value Vd cannot be maintained above the voltage threshold Vth before the check section Chk2 elapses from time t5, the battery 19 is charged again. The charging section CS is provided for performing the above. That is, the charging section CS is performed twice or more. By doing so, the battery capacity of the battery 19 can be reliably recovered, and the engine 23 can be started more reliably.

  Thereafter, when the start condition necessary for the operation of the engine 23 is satisfied, the external device EX transmits a start signal to the start control unit 17a to operate the rotating electrical machine main body unit 17b, or performs control to supply fuel to the engine 23. For example, the engine 23 is started. The starting condition may be set arbitrarily. For example, the condition where the accelerator pedal is depressed, the condition where the brake pedal is released (not depressed), the condition where the starting operation is performed, and the like are applicable.

[Embodiment 2]
The second embodiment will be described with reference to FIG. For simplicity of illustration and description, unless otherwise specified, the same elements as those used in the first embodiment are denoted by the same reference numerals and description thereof is omitted. Therefore, differences from the first embodiment will be mainly described.

  A vehicle 110 shown in FIG. 8 is a configuration example of a gasoline automobile. The gasoline automobile referred to in this specification means a vehicle that obtains power by burning fossil fuel (oil, natural gas, etc.). The vehicle 110 includes batteries 11 and 19, an electric load 12, wheels 14, a transmission 15, a rotating electrical machine 17, power transmission members 18 and 22, an engine 23, and the like.

  The engine start system 10A includes at least the rotating electrical machine 17 and the voltage sensor 30 as in the first embodiment. Further, the starting control unit 17a and the rotating electrical machine main body 17b constituting the rotating electrical machine 17 can be configured in the same manner as in the first embodiment (see FIGS. 2 and 3). According to this configuration, since the start control process shown in FIG. 4 and the charge control process shown in FIG. 5 can be executed, a control example as shown in FIG. 7 can be realized.

[Embodiment 3]
The third embodiment will be described with reference to FIGS. For simplicity of illustration and description, unless otherwise specified, the same elements as those used in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted. Therefore, differences from Embodiments 1 and 2 will be mainly described.

  A vehicle 120 shown in FIG. 9 is a configuration example of a hybrid vehicle as in the first embodiment. The vehicle 120 includes batteries 11, 19, 20, an electric load 12, a converter 13, wheels 14, a transmission 15, rotating electrical machines 16 and 51, power transmission members 18 and 22, an inverter 21, an engine 23, a power conversion control device 24, A start control unit 50 and the like are included. Among these elements, the engine start system 10B includes at least a start control unit 50, a rotating electrical machine 51, a voltage sensor 30 (see FIG. 10), and the like.

  The vehicle 120 is different from the vehicle 100 shown in FIG. 1 in the configuration of the engine start system 10. That is, the vehicle 100 includes the start control unit 17 a in the rotating electrical machine 17, whereas the vehicle 120 includes the start control unit 50 separately from the rotating electrical machine 51. The start control unit 50 corresponds to the start control unit 17 a and is interposed between the external device EX and the rotating electrical machine 51. In other words, the start control unit 50 may be added to the conventional hybrid vehicle. The start control unit 50 corresponds to an ECU, a computer, or the like.

  The start control unit 50 shown in FIG. 10 includes an engine stop unit 50a, a start possibility determination unit 50b, a charge control unit 50c, a power conversion control unit 50d, and the like. The engine stop unit 50a has a function of stopping the engine 23 when it is determined by the start possibility determination unit 50b that power necessary for starting the engine 23 can be supplied. The engine stop means 50a may be configured in the same manner as the signal output means 171 shown in FIG. 2, or may include the function of the signal output means 171 and the function of the external device EX. In the latter configuration, control for stopping the engine 23 (for example, stop of fuel supply) is performed based on the determination result signal SC transmitted from the startability determination unit 50b.

  The startability determination unit 50b is configured in the same manner as the startability determination unit 172 shown in FIG. The charge control means 50c is configured similarly to the charge control means 173 shown in FIG. The power conversion control means 50d is configured similarly to the power conversion control means 174 shown in FIG. The rotating electrical machine 51 is configured in the same manner as the rotating electrical machine main body 17b shown in FIG.

  According to the configuration described above, the start control process shown in FIG. 4 and the charge control process shown in FIG. 5 can be executed, so that a control example as shown in FIG. 7 can be realized.

[Embodiment 4]
The fourth embodiment will be described with reference to FIG. For simplicity of illustration and description, unless otherwise specified, the same elements as those used in the first to third embodiments are denoted by the same reference numerals and description thereof is omitted. Therefore, differences from Embodiments 1 to 3 will be mainly described.

  A vehicle 130 shown in FIG. 11 is a configuration example of a gasoline automobile as in the second embodiment. The vehicle 130 includes batteries 11 and 19, an electric load 12, wheels 14, a transmission 15, a rotating electrical machine 51, power transmission members 18 and 22, an engine 23, a start control unit 50, and the like.

  As in the third embodiment, engine start system 10B includes at least start control unit 50, rotating electric machine 51, voltage sensor 30 (see FIG. 10), and the like. According to this configuration, since the start control process shown in FIG. 4 and the charge control process shown in FIG. 5 can be executed, a control example as shown in FIG. 7 can be realized.

[Other Embodiments]
In the above, although the form for implementing this invention was demonstrated according to Embodiment 1-4, this invention is not limited to the said form at all. In other words, various forms can be implemented without departing from the scope of the present invention. For example, the following forms may be realized.

  The rotary electric machine 17 shown in the first and second embodiments and the rotary electric machine 51 shown in the third and fourth embodiments are both configured to function as an electric motor and a generator (FIGS. 1, 8, and 9). , See FIG. Instead of this form, a configuration may be adopted in which an electric motor and a generator are provided separately. The electric motor includes a case where the rotating electric machine functions as an electric motor. The generator includes a case where the rotating electrical machine functions as a generator. For example, instead of the rotating electrical machine main body 17b (see FIG. 2) shown in the first and second embodiments, an example including an electric motor 17c and a generator 17d is shown in FIG. Similarly, instead of the rotating electrical machine 51 shown in Embodiment 3 (see FIG. 9), an example including an electric motor 51a and a generator 51b is shown in FIG. In FIG. 13, an engine start system 10C includes at least a start control unit 50, an electric motor 51a, a generator 51b, a voltage sensor 30, and the like. Although not shown, the same applies to the case where an electric motor 51a and a generator 51b are provided instead of the rotating electrical machine 51 (see FIG. 11) shown in the fourth embodiment. Since it is only the difference whether it is provided with a rotary electric machine or an electric motor and a generator, the effect similar to Embodiment 1-4 can be obtained.

  In the above-described first to fourth embodiments, the voltage sensor 30 and the current sensor 31 are configured separately from the start control units 17a and 50 (see FIGS. 2, 3, and 10). Instead of this configuration, one or both of the voltage sensor 30 and the current sensor 31 may be integrated with the start control units 17a and 50. The same applies to the current sensor 32 and the switch unit SW2 (separation switch). Since it is only a difference whether it is provided in a separate body or provided integrally, it is possible to obtain the same effect as in the first to fourth embodiments.

  In the first to fourth embodiments described above, the start control units 17a and 50 are configured separately from the external device EX (see FIGS. 2, 9, 11, and 12). Instead of this form, a configuration in which the start control units 17a and 50 and the external device EX are integrally provided, that is, a configuration in which the start control units 17a and 50 are provided in the external device EX may be employed. Since it is only a difference whether it is provided in a separate body or provided integrally, it is possible to obtain the same effect as in the first to fourth embodiments.

  In the first and second embodiments described above, the signal output means 171 and the startability determination means 172 are provided separately (see FIG. 2). Instead of this form, the signal output means 171 and the startability determination means 172 may be integrated. Similarly, in the third and fourth embodiments, the engine stop unit 50a and the startability determination unit 50b are provided separately (see FIG. 10). Instead of this form, the engine stop means 50a and the startability determination means 50b may be configured integrally. Since it is only a difference whether it comprises by another body or it comprises integrally, the effect similar to Embodiment 1-4 can be obtained.

[Function and effect]
According to the embodiments described above and other embodiments, the following effects can be obtained.

(1) In the rotating electrical machine 17, when the start control unit 17a satisfies a stop condition that does not require the operation of the engine 23, the stop request signal SA is transmitted from the external device EX, and the field current If is supplied to the field winding Lf. Without flowing, the stator current Is flows from the battery 19 to the stator windings Lu, Lv, Lw, the voltage value Vd measured by the voltage sensor 30 is equal to or higher than the voltage threshold Vth, and the stator current Is measured by the current sensor 31. Startability determination means 172 for determining whether or not the battery 19 can supply power necessary for the next start of the engine 23 based on whether or not (current value) is equal to or greater than the current threshold Ith , and startability determination means If it is determined that can supply the necessary power to start the engine 23 by 172, the engine to an external apparatus EX in order to stop the engine 23 2 Of a structure and a signal output unit 171 outputs a stop permission signal SB to allow stop (see FIG. 1-8, FIG. 12).

According to this configuration, the startability determination unit 172 measures the voltage value Vd of the battery 19 and the stator current Is flowing through the stator windings Lu, Lv, and Lw when the stop condition is satisfied (particularly immediately before the engine 23 is stopped). I do. Whether or not the battery 19 can supply electric power necessary for the next start of the engine 23 depending on whether or not the measured voltage value Vd is equal to or greater than the voltage threshold Vth and the measured stator current Is is equal to or greater than the current threshold Ith . Determine. Since this determination is not affected by the operation state of the engine 23 until the engine 23 is stopped, the determination accuracy can be improved as compared with the conventional case. Further, since the stator current Is is passed through the stator windings Lu, Lv, and Lw in a state where no current is passed through the field winding Lf, no output torque is generated in the rotating electrical machine 17. Therefore, it is possible to prevent the engine 23 from operating carelessly.

  (2) When it is determined by the start possibility determination means 172, 50b that the start control units 17a, 50 cannot supply power necessary for starting the engine 23, the start control units 17a, 50 operate the engine 23 without stopping the engine 23. And charging control means 173 and 50c for controlling the electric power generated in the rotating electrical machines 17 and 51 to charge the battery 19, and the signal output means 171 (or the engine stop means 50a) The charging control means 173, 50c charges the battery 19 until the charging termination condition for terminating the charging is satisfied, and then the stop permission signal SB is output (see FIGS. 4, 5, and 7). According to this configuration, the charge control means 173 and 50 c generate power by forcibly continuing the operation of the engine 23 and charge the battery 19 even when the stop condition is satisfied. Further, charging is performed by the charging control means 173, 50c until the charging termination condition is satisfied. Therefore, since it is fully considered that the battery capacity is restored by charging the battery 19, the engine 23 can be started more reliably and the determination accuracy is improved.

  (3) The charging end condition includes one or both of a charging time CT that is a charging time and a charging current amount CV that is a charging current amount (see step S32 in FIG. 5). ). According to this configuration, it is possible to easily set the timing for terminating the charging of the battery 19.

  (4) When it is determined by the start possibility determination means 172, 50b that the charge control means 173, 50c cannot supply the electric power necessary for starting the engine 23, the charge control means 173, 50c is based on the voltage value Vd measured by the voltage sensor 30. One or both of the charging time CT and the charging current amount CV is changed (see FIGS. 5 to 7). According to this configuration, the time from when the stop condition is satisfied to when the engine 23 is stopped can be optimized, and the time can be minimized. In addition, it is possible to minimize the frequency of determination by the startability determination means 172, 50b and suppress wasteful power consumption.

(5) having a switch unit SW2 for switching connection / disconnection between the first power line PL connected to the battery 19 and the second power line CL connected to the battery 11 which is a power source separate from the battery 19, The start control units 17a and 50 do not connect the first power line PL and the second power line CL until at least whether the power necessary for starting the engine 23 can be supplied after satisfying the stop condition. The switch part SW2 (separation switch) is switched to the above (see FIGS. 1, 4, 8, 9, 11, and 13). According to this configuration, when the startability is determined, the first power line PL and the second power line CL are disconnected (that is, the switch unit SW2 is turned off), so that the engine 23 is based on the battery capacity of the battery 19. Can be accurately determined.

(6) In the engine start systems 10B and 10C, when the start control unit 50 satisfies the stop condition, the stop request signal SA is transmitted from the external device EX, and the field current If does not flow through the field winding Lf. Current flows from the battery 19 to the stator windings Lu, Lv, Lw, the voltage value Vd measured by the voltage sensor 30 is equal to or greater than the voltage threshold Vth, and the stator current Is measured by the current sensor 31 is equal to or greater than the current threshold Ith. Depending on whether or not the battery 19 can supply power necessary for starting the engine 23 next time, the startability determining means 50b for determining whether or not the battery 19 can supply power necessary for starting the engine 23, and the power required for starting the engine 23 by the startability determining means 50b. When it is determined that the engine can be supplied, an engine stop means 50a for stopping the engine 23 is provided (FIGS. 9 to 11). Referring to FIG. 13).

According to this configuration, the startability determination unit 50b measures the voltage value Vd of the battery 19 and the stator current Is flowing in the stator windings Lu, Lv, and Lw when the stop condition is satisfied (particularly immediately before the engine 23 is stopped). I do. Depending on whether or not the measured voltage value Vd is equal to or greater than the voltage threshold value Vth and the measured stator current Is (current value) is equal to or greater than the current threshold value Ith, the battery 19 supplies electric power necessary for starting the engine 23 next time. It is determined whether or not it can be supplied. Since this determination is not affected by the operation state of the engine 23 until the engine 23 is stopped, the determination accuracy can be improved as compared with the conventional case. Further, since the stator current Is is passed through the stator windings Lu, Lv, Lw in a state where no current is passed through the field winding Lf, no output torque is generated in the rotating electrical machine 51 (51a, 51b). Therefore, it is possible to prevent the engine 23 from operating inadvertently.

10 (10A, 10B, 10C) Engine start system 11, 19, 20 Battery 17, 51 Rotating electrical machine 17a, 50 Start controller 171 Signal output means 172, 50b Start possibility determination means 23 Engine 30 Voltage sensor 31, 32 Current sensor EX External device Is Stator current (stator current)
Lf Field winding Lu, Lv, Lw Stator winding (stator winding)
SA stop request signal SB stop permission signal

Claims (10)

In a rotating electrical machine (17) mechanically connected to an engine (23) and having a rotating electrical machine main body (17b) having a stator winding (Lu, Lv, Lw) and a field winding (Lf ). ,
When a start condition necessary for operation of the stopped engine is satisfied, a start signal is transmitted from the external device (EX), and current is supplied from the battery (19) to the stator winding and the field winding. And a start control unit (17a) for performing control to operate the rotating electrical machine main body unit to start the engine ,
The start controller is
When a stop condition that does not require the operation of the engine is satisfied, a stop request signal (SA) is transmitted from the external device, and the current (If) does not flow through the field winding, and the battery turns to the stator winding. A voltage value (Vd) measured by a voltage sensor for passing a current (Is) and measuring the voltage of the battery is equal to or greater than a voltage threshold (Vth), and is measured by a current sensor for measuring a current flowing through the stator winding. Startability determination means (172) for determining whether or not the battery can supply electric power necessary for the next start of the engine based on whether or not the current value (Is) is equal to or greater than the current threshold (Ith). ,
When it is determined by the start possibility determination means that it is possible to supply power necessary for the next start of the engine, a stop permission signal (SB) for permitting the external device to stop the engine to stop the engine. ) To output signal output means (171);
A rotating electric machine comprising: When the startability determination unit determines that the electric power necessary for starting the engine cannot be supplied by the startability determination unit, the start control unit continues the operation of the engine without stopping the engine. Charging control means (173) for performing control to charge the battery with electric power generated in
The signal output means outputs the stop permission signal after charging the battery by the charge control means until a charge termination condition for ending charging of the battery is satisfied. The rotating electrical machine described in 1.   The charge completion condition includes one or both of a charge time (CT) that is a charge time and a charge current amount (CV) that is a charge current amount. The rotating electrical machine described.   When it is determined by the start possibility determination unit that the electric power necessary for starting the engine cannot be supplied, the charge control unit determines the charge time and the charge current amount based on a voltage value measured by the voltage sensor. The rotating electrical machine according to claim 3, wherein one or both of them are changed. A switch unit (SW2) that switches connection / disconnection between a first power line (PL) connected to the battery and a second power line (CL) connected to a power source separate from the battery;
The start control unit does not connect the first power line and the second power line until at least whether the power necessary for starting the engine can be supplied after the stop condition is satisfied. The rotating electrical machine according to any one of claims 1 to 4, wherein the switch unit is switched. A rotating electrical machine (51) mechanically connected to the engine (23) and having a stator winding (Lu, Lv, Lw) and a field winding (Lf);
When a start condition necessary for operation of the stopped engine is satisfied, a start signal is transmitted from the external device (EX), and current is supplied from the battery (19) to the stator winding and the field winding. A start control unit (50) for controlling the rotating electrical machine to start the engine .
In an engine start system (10, 10B, 10C) that stops the engine when a stop condition that does not require operation of the engine is satisfied, and starts the engine when a start condition that requires operation of the stopped engine is satisfied. ,
The start controller is
When the stop condition is satisfied, a stop request signal (SA) is transmitted from the external device, and a current (Is) is supplied from the battery to the stator winding without supplying a current (If) to the field winding. The voltage value (Vd) measured by the voltage sensor that measures the battery voltage is equal to or greater than the voltage threshold (Vth), and the current value (Is) measured by the current sensor that measures the current flowing through the stator winding. Startability determination means (50b) for determining whether or not the battery can supply electric power necessary for the next start of the engine depending on whether or not is equal to or greater than a current threshold value (Ith) ;
An engine stop means (50a) for stopping the engine when it is determined by the start possibility determination means that the electric power necessary for the next start of the engine can be supplied;
An engine start system comprising: When the startability determination unit determines that the electric power necessary for starting the engine cannot be supplied by the startability determination unit, the start control unit continues the operation of the engine without stopping the engine. Charging control means ( 50c ) for performing control to charge the battery with electric power generated in
The engine stop means causes the external device to stop the engine so as to stop the engine after charging the battery by the charge control means until a charge termination condition for ending charging of the battery is satisfied. The engine start system according to claim 6, wherein a stop permission signal (SB) to be permitted is output.   The charge end condition includes one or both of a charge time (CT) that is a charge time and a charge current amount (CV) that is a charge current amount. The engine starting system as described.   When it is determined by the start possibility determination unit that the electric power necessary for starting the engine cannot be supplied, the charge control unit determines the charge time and the charge current amount based on a voltage value measured by the voltage sensor. 9. The engine starting system according to claim 8, wherein one or both of them are changed. A switch unit (SW2) that switches connection / disconnection between a first power line (PL) connected to the battery and a second power line (CL) connected to a power source separate from the battery;
The start control unit does not connect the first power line and the second power line until at least whether the power necessary for starting the engine can be supplied after the stop condition is satisfied. The engine start system according to any one of claims 6 to 9, wherein the switch unit is switched.

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