JP2018204553A - Electronic control device - Google Patents

Abstract

To provide an electronic control device capable of determining a compression stroke of an engine, with a simple structure.SOLUTION: In an electronic control device 100, a determining portion 132b performs compression stroke determination for determining that an engine stroke in a compression stroke, when the voltage of a lead battery 101 detected by a voltage detecting portion 132a after a three-phase AC generator 110 starts the driving of a crank shaft becomes less than a predetermined threshold value Vth. A control portion 132 controls a duty for driving the three-phase AC generator 110 so as to maintain the voltage of the lead battery 101 at the predetermined threshold value Vth or more in a period since the three-phase AC generator 110 starts the driving of the crank shaft till the determining portion 132b performs the compression stroke determination.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic control device, and more particularly, to an electronic control device for a vehicle that charges a secondary battery such as a lead battery with a three-phase AC generator and starts an internal combustion engine using the three-phase AC generator.

  2. Description of the Related Art In recent years, in vehicles such as automobiles, a rotor having a field magnetic flux generating magnet that is connected to a crankshaft (crankshaft) of an engine that is an internal combustion engine and that is driven by the rotation thereof, and a stator winding for generating electric power output Using a three-phase alternator with a stator wound around, control to charge a secondary battery such as a lead battery, and control to start the engine by rotating the crankshaft of the engine An electronic control device has been proposed.

  Under such circumstances, Patent Document 1 relates to a starter and a start control device for an internal combustion engine. At the start of the engine, the starter motor is reversely rotated to reverse the crankshaft and the piston is once returned to the exhaust stroke, and then the starter motor is turned on. A configuration is disclosed in which the engine is started from a state in which the piston rotates forward and the piston is in the exhaust stroke.

Japanese Patent No. 4230116

  However, according to the study of the present inventor, in the configuration of Patent Document 1, specifically, the crankshaft from the power supply voltage and the engine temperature to the compression top dead center based on data such as a map held in advance. Determine the time required to reverse the rotation, perform the reverse rotation, monitor the rotation speed (time between crank pulses), etc. during the reverse rotation operation, determine the compression top dead center from the rate of decrease in the rotation speed, reverse rotation It is necessary to have a configuration in which the compression top dead center is determined by detecting from the crank pulse that the rotation has been forward rotated by the compression reaction force of the compression top dead center during operation. For this reason, according to the configuration of Patent Document 1, it is necessary to hold a plurality of types of data in accordance with the power supply voltage and temperature conditions, and to change the data. It is necessary to keep. Further, the rotation speed ratio must be calculated for each crank pulse, which is a processing load. Furthermore, the determination accuracy of the compression top dead center changes depending on the detection accuracy of the crank position, and in order to accurately determine the compression top dead center, it is necessary to detect the crank position finely by increasing the number of teeth of the retractor.

  Further, according to the study of the present inventor, in the configuration of Patent Document 1, the minimum voltage of the power supply voltage at the start of the reverse rotation operation is held, and compression is performed when a power supply voltage lower than the held minimum voltage is detected. A configuration in which the top dead center is determined may also be adopted, but in such a case, depending on the engine temperature and the power supply voltage, the lowest power supply voltage at the start of the reverse operation is lower than the power supply voltage at the compression top dead center Therefore, there is a possibility that the compression top dead center cannot be determined.

  The present invention has been made through the above-described studies, and an object thereof is to provide an electronic control device capable of determining the compression stroke of an engine with a simple configuration.

  In order to achieve the above object, the present invention provides an electronic control device including a voltage detection unit that detects a voltage of a battery that supplies power to an electric motor that is driven to rotate a crankshaft of an engine that is an internal combustion engine. When the battery voltage detected by the voltage detection unit is less than a predetermined threshold after the electric motor starts the driving of the crankshaft, it is determined that the stroke of the engine is in the compression stroke A determination unit that performs a compression stroke determination; and a voltage of the battery continues to be equal to or higher than the predetermined threshold in a period from when the electric motor starts the driving of the crankshaft until the determination unit determines the compression stroke. And a control unit that controls a duty for driving the electric motor so as to be maintained as a first aspect.

  In addition to the first aspect, the present invention has a second aspect in which the control unit gradually increases the duty to a predetermined value.

  According to the present invention, in addition to the first or second aspect, the determination unit starts from the time point when the electric motor starts the driving, and the voltage of the battery within the predetermined time is the predetermined threshold value. It is a third aspect to determine that the stroke of the engine is in the compression stroke when it becomes less than.

  Further, according to the present invention, in addition to any one of the first to third aspects, the driving of the electric motor rotates the crankshaft in a direction opposite to that during operation of the engine. The fourth aspect is assumed.

  In addition to any one of the first to fourth aspects, the present invention has a fifth aspect that the engine is a single-cylinder internal combustion engine.

  According to the electronic control device according to the first aspect of the present invention described above, when the voltage of the battery detected by the voltage detector after the electric motor starts driving the crankshaft becomes less than a predetermined threshold value, The battery voltage is predetermined during a period from when the electric motor starts driving the crankshaft until the determination unit makes a compression stroke determination after determining that the engine stroke is in the compression stroke. And a control unit that controls the duty for driving the electric motor so as to be continuously maintained above the threshold value. Therefore, it is possible to determine the compression stroke of the engine with a simple configuration. it can. In addition, it is not necessary to store data such as a map according to the power supply voltage and temperature conditions, and the memory capacity can be reduced. In addition, since the compression stroke of the engine can be determined even in a processing cycle with a low processing priority, it is not necessary to increase the load of a task with a high processing priority that is synchronized with a crank pulse. In addition, since the crank position detection signal is not used, it is possible to determine the compression stroke of the engine regardless of the detection accuracy of the crank position. In addition, it is possible to suppress erroneous determination of the compression top dead center due to a drop in the power supply voltage at the start of the reverse rotation operation.

  Further, according to the electronic control device according to the second aspect of the present invention, since the control unit gradually increases the duty to a predetermined value, the determination of the compression stroke of the engine can be performed more reliably with a simple configuration. can do.

  According to the electronic control device of the third aspect of the present invention, the determination unit starts when the electric motor starts driving, and the battery voltage becomes less than the predetermined threshold value within a predetermined time. In addition, since it is determined that the engine stroke is in the compression stroke, the compression stroke of the engine can be determined more reliably and practically with a simple configuration.

  Further, according to the electronic control device according to the fourth aspect of the present invention, the drive of the electric motor rotates the crankshaft in the direction opposite to that during the operation of the engine. It is possible to accurately determine the compression stroke of the engine and contribute to more reliable engine start.

  Further, according to the electronic control device according to the fifth aspect of the present invention, since the engine is a single cylinder internal combustion engine, the compression stroke of the engine can be more reliably determined with a simple configuration. .

FIG. 1 is a circuit diagram showing a configuration of an electronic control device according to an embodiment of the present invention. FIG. 2 is a flowchart showing an example of the flow of the compression stroke determination process executed by the electronic control device in the present embodiment. FIG. 3 is a diagram illustrating an example of the relationship between the elapsed time from the reverse rotation operation start time and the duty of the three-phase AC generator in the compression stroke determination process executed by the electronic control device in the present embodiment.

  Hereinafter, an electronic control device according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

〔Constitution〕
First, with reference to FIG. 1, the structure of the electronic control apparatus in embodiment of this invention is demonstrated in detail.

  FIG. 1 is a circuit diagram illustrating a configuration of an electronic control device according to the present embodiment.

  As shown in FIG. 1, an electronic control device 100 according to the present embodiment is typically mounted on a vehicle such as a motorcycle, and a lead battery 101 that is a secondary battery is charged by a three-phase AC generator 110. An ECU (Electronic Control Unit) 130 is provided for starting the engine by rotating a crankshaft of an engine, which is a single-cylinder internal combustion engine, using a three-phase AC generator 110.

  Reference numeral 102 in the figure denotes a voltage sensor that detects a voltage difference between the positive electrode and the negative electrode of the lead battery 101 as the voltage of the lead battery 101, and reference numeral 103 denotes a crank angle that detects the rotation angle of the crankshaft of the engine. The sensor is shown. In addition to the lead battery, a nickel metal hydride battery or a lithium ion battery can be used as the secondary battery. In addition, the voltage of the lead battery 101 is not limited to the voltage difference between the positive electrode and the negative electrode of the lead battery 101, but can detect the voltage drop when the three-phase AC generator 110 is energized. If so, the voltage difference between the positive electrode side and the negative electrode side in the electric circuit including the lead battery 101 and the three-phase AC generator 110 may be detected.

  Although the detailed configuration of the three-phase AC generator 110 is omitted, a three-phase power generation output generating coil (stator winding) including a U-phase coil 110a, a V-phase coil 110b, and a W-phase coil 110c. ) And a permanent magnet for generating a field flux corresponding to each of the coils 110a and 110b and 110c of each phase are mounted and arranged so as to circulate on the outer peripheral side of the stator. And a rotor connected to the crankshaft of the engine.

  The U-phase coil 110 a is electrically connected to the other terminal of one U-phase switching element 131 a of the AC / DC converter 131 and one terminal of the other U-phase switching element 131 b of the AC / DC converter 131. It has a connection terminal 111a to be connected to. The V-phase coil 110 b is electrically connected to the other terminal of one V-phase switching element 131 c of the AC / DC converter 131 and one terminal of the other V-phase switching element 131 d of the AC / DC converter 131. It has a connection terminal 111b to be connected to. The W-phase coil 110c is connected to the other terminal of one W-phase switching element 131e of the AC / DC converter 131 and one terminal of the other W-phase switching element 131f of the AC / DC converter 131. A connection terminal 111c for electrical connection is provided.

  Here, the change with time of the output voltage output from the three-phase AC generator 110 is synchronized with the rotation of the rotor of the three-phase AC generator 110 driven by the crankshaft of the engine. Specifically, assuming that one cycle of the rotation direction phase (rotation phase: rotation angle) of the rotor is 360 ° (one rotation of the rotor), the U-phase coil 110a with respect to one rotation phase of the rotor. And the phase of the corresponding permanent magnet is 120 degrees earlier than the phase of the V-phase coil 110b and the corresponding permanent magnet, and the phase of the V-phase coil 110b and the corresponding permanent magnet is W-phase coil 110c. The phase is set to be 120 ° earlier than the phase of the corresponding permanent magnet. Correspondingly, the output voltage output from the U-phase coil 110a is advanced in phase by 120 ° from the output voltage output from the V-phase coil 110b, and the output voltage output from the V-phase coil 110b. Is set so that the phase advances by 120 ° from the output voltage output from the W-phase coil 110c.

  The ECU 130 is an arithmetic processing unit including a microcomputer and the like, and includes an AC (Alternate Current) / DC (Direct Current) converter 131, which is a power converter, a control unit 132, a memory 133, and a timer 134. The AC / DC converter 131 may be provided outside the ECU 130 as a power module or the like.

  The AC / DC converter 131 typically includes switching elements 131a, 131b, 131c, 131d, 131e, and 131f connected in a three-phase bridge, and the switching elements 131a, 131b, 131f, and 131f according to a control signal from the control unit 132. Each of 131c, 131d, 131e, and 131f is turned on or off to convert the three-phase alternating current supplied from the three-phase alternating current generator 110 into a direct current, and supply the direct current to the lead battery 101. In addition, the AC / DC converter 131 turns on each of the switching elements 131a, 131b, 131c, 131d, 131e, and 131f in accordance with a control signal from the control unit 132 to turn on or turn off the direct current supplied from the lead battery 101. Is converted into a three-phase alternating current and a three-phase alternating current is supplied to the three-phase alternating current generator 110. In such a case, the AC / DC converter 131 functions as a DC / AC converter. Note that each of the switching elements 131a, 131b, 131c, 131d, 131e, and 131f is typically a transistor. In FIG. 1, as an example, an N-type MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is used. Each is shown.

  Specifically, the AC / DC converter 131 corresponds to a pair of switching elements 131a, 131b, 131c, 131d, 131e, and 131f for each of the three phases U phase, V phase, and W phase. Have.

  That is, in the AC / DC converter 131, the pair of U-phase switching elements 131a and 131b are electrically connected, the switching element 131a is in the on state, and the switching element 131b is in the off state. The U-phase output voltage is set to the high level, and the U-phase output voltage is set to the low level when the switching element 131a is in the off state and the switching element 131b is in the on state.

  Further, in AC / DC converter 131, when a pair of switching elements 131c of V phase and switching element 131d are electrically connected, switching element 131c is on and switching element 131d is off. The V-phase output voltage is set to a high level, the V-phase output voltage is set to a low level when the switching element 131c is in an off state and the switching element 131d is in an on state.

  Further, in AC / DC converter 131, a pair of switching elements 131e of W phase and switching element 131f are electrically connected, and when switching element 131e is on and switching element 131f is off, W When the phase output voltage is set to the high level, the switching element 131e is in the off state, and the switching element 131f is in the on state, the W phase output voltage is set to the low level.

  Here, the switching element 131a includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high potential side of the lead battery 101, the switching element 131b, and three-phase AC power generation. And the other input terminal electrically connected to the connection terminal 111a of the machine 110. The switching element 131a is turned on / off in accordance with a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131a is in the on state, a current flows from one input terminal to the other input terminal. Flows.

  The switching element 131b includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the switching element 131a and the connection terminal 111a of the three-phase AC generator 110, and a lead battery. And the other input terminal electrically connected to the low potential side of 101. The switching element 131b is turned on / off in accordance with a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131b is in the on state, a current flows from one input terminal to the other input terminal. Flowing.

  The switching element 131c includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high potential side of the lead battery 101, a switching element 131d, and a three-phase AC generator. 110, and the other input terminal electrically connected to the connection terminal 111b. The switching element 131c is turned on / off according to a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131c is in the on state, a current is passed from one input terminal to the other input terminal. Flowing.

  The switching element 131d includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the switching element 131c and the connection terminal 111b of the three-phase AC generator 110, and a lead battery. And the other input terminal electrically connected to the low potential side of 101. The switching element 131d is turned on / off in accordance with a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131d is in the on state, a current flows from one input terminal to the other input terminal. Flowing.

  The switching element 131e includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the high potential side of the lead battery 101, a switching element 131f, and a three-phase AC generator. The other input terminal electrically connected to 110 connection terminals 111c. The switching element 131e is turned on / off according to a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131e is in the on state, a current is passed from one input terminal to the other input terminal. Flowing.

  Furthermore, the switching element 131f includes a control terminal electrically connected to the control unit 132, one input terminal electrically connected to the switching element 131e and the connection terminal 110c of the three-phase AC generator 110, and a lead battery. And the other input terminal electrically connected to the low potential side of 101. The switching element 131f performs an on / off operation according to a predetermined control signal applied from the control unit 132 to the control terminal. When the switching element 131f is in an on state, a current is passed from one input terminal to the other input terminal. Flowing.

  The control unit 132 reads the necessary control program and control data from the memory 133 and executes the control program, thereby controlling the overall operation of the ECU 130. The controller 132 is connected to the voltage sensor 102 and the crank angle sensor 103, and an electric signal indicating the voltage of the lead battery 101 detected by the voltage sensor 102 and an electric angle indicating the rotation angle of the crankshaft detected by the crank angle sensor 103. A signal is input. The control unit 132 includes a voltage detection unit 132a and a determination unit 132b as functional blocks.

  Further, the control unit 132 executes a compression stroke determination process, which will be described in detail later. In the compression stroke determination process, the voltage detection unit 132a detects the voltage of the lead battery 101 via the voltage sensor 102. When the determination unit 132b starts driving the crankshaft of the engine by the three-phase AC generator 110 and when the voltage of the battery 101 thereafter becomes less than a predetermined threshold, the engine stroke is in the compression stroke. This is a judgment. At this time, the voltage of the battery 101 becomes equal to or higher than a predetermined threshold during the period from when the three-phase AC generator 110 starts driving the crankshaft of the engine until the determination unit 132b determines the compression stroke. The duty for driving the three-phase AC generator 110 is controlled so as to be continuously maintained.

  The memory 133 stores necessary control programs and control data. The timer 134 executes various timing processes according to the control signal from the control unit 132.

  In the electronic control device 100 having such a configuration, when the engine is started by rotating the crankshaft of the engine using the three-phase AC generator 110, the control unit 132 executes a compression stroke determination process shown below. Thus, with a simple configuration, the compression stroke determination, which is a determination indicating that the engine stroke is in the compression stroke, more specifically, the position of the piston of the engine is at the compression top dead center is performed. Hereinafter, with reference to FIG. 2 and FIG. 3, the operation of the control unit 132 when executing the compression stroke determination process will be described.

[Compression stroke determination process]
FIG. 2 is a flowchart illustrating an example of the flow of the compression stroke determination process executed by the electronic control apparatus 100 according to the present embodiment. FIG. 3 is a diagram illustrating an example of the relationship between the elapsed time from the reverse rotation operation start time and the duty of the three-phase AC generator in the compression stroke determination process executed by the electronic control unit 100 according to the present embodiment. It is.

  The compression stroke determination process shown in FIG. 2 is started when the ignition switch of the vehicle is switched from the off state to the on state and the ECU 130 of the electronic control device 100 is operated, and the compression stroke determination process proceeds to the process of step S1. In this compression stroke determination process, when the crankshaft is rotated in the same forward direction as the engine is running (forward rotation), the engine piston is compressed so that it moves from before the compression top dead center to after the compression top dead center. From the viewpoint of ensuring that the top dead center can be overcome, the engine is started once by rotating (reversely rotating) the crankshaft in the direction opposite to that during engine operation. It is also possible to execute the compression stroke determination process when the engine is started by rotating the crankshaft in the same direction as during operation of the engine.

  In the process of step S1, the control unit 132 starts driving the three-phase AC generator 110 (electric motor) using the electric power of the lead battery 101, thereby rotating the crankshaft in the direction opposite to that during engine operation. Therefore, a control signal instructing to start the engine is output to the AC / DC converter 131 by rotating the crankshaft of the engine in a direction opposite to that during engine operation using the three-phase AC generator 110. Prior to starting the timing operation of the timer 134, the time (reverse rotation start time) at which the three-phase AC generator 110 starts the reverse rotation operation is acquired and stored in the memory 133 based on the initial count value at the start. Equally hold. Thereby, the process of step S1 is completed, and the compression stroke determination process proceeds to the process of step S2. The reverse rotation start time is indicated by time t = T0 in FIGS. 3 (a) and 3 (b).

  In the process of step S2, the voltage detection unit 132a detects the initial value of the current voltage (motor drive voltage) V of the lead battery 101 via the voltage sensor 102, and the control unit 132 sets the initial value to a predetermined threshold value. It is possible to confirm that it is Vth or higher. Thereby, the process of step S2 is completed, and the compression stroke determination process proceeds to the process of step S3. When the initial value of the voltage V of the lead battery 101 is less than the predetermined threshold value Vth, the current compression stroke determination process can be terminated as it is.

  In the process of step S <b> 3, the control unit 132 acquires the current time t based on the current count value of the timer 134. Thereby, the process of step S3 is completed, and the compression stroke determination process proceeds to the process of step S4.

  In the process of step S4, the control unit 132 indicates the relationship between the elapsed time (t−T0) from the reverse rotation start time T0 to the current time t and the duty value for driving the three-phase AC generator 110. A duty value corresponding to the elapsed time from the reverse rotation start time T0 to the current time t acquired in the process of step S3 is searched from the duty table. The duty table is set in advance and stored in the memory 133. As shown in FIG. 3A, the duty value is set between the reverse rotation start time T0 and the duty drive end time TE. May be set to be held at a constant value, and as shown in FIG. 3B, the duty value becomes a predetermined value (100 in the illustrated example) as the elapsed time from the reverse drive start time T0 increases. It may be set so as to gradually increase up to 80% or 90%. Further, at this time, the duty value may be corrected by multiplying the duty value by a correction coefficient calculated from a state relating to the vehicle such as the engine temperature, the atmospheric temperature, the throttle temperature, and the voltage of the lead battery 101. . Thereby, the process of step S4 is completed, and the compression stroke determination process proceeds to the process of step S5.

  In the process of step S5, the control unit 132 outputs a control signal that can drive the three-phase AC generator 110 with the duty value searched in the process of step S4 to the AC / DC converter 131, thereby leading to lead. The driving of the three-phase AC generator 110 is started using the electric power of the battery 101, and the crankshaft is rotated in the direction opposite to that during operation of the engine. At this time, the drive current from the start of the reverse operation of the three-phase AC generator 110 is limited so that the voltage of the lead battery 101 can be maintained at a predetermined threshold value Vth or higher. Thereby, the process of step S5 is completed, and the compression stroke determination process proceeds to the process of step S6.

  In the process of step S <b> 6, the voltage detection unit 132 a detects the current voltage (motor drive voltage) V of the lead battery 101 during driving of the three-phase AC generator 110 via the voltage sensor 102. Thereby, the process of step S6 is completed and the compression stroke determination process proceeds to the process of step S7.

  In the process of step S7, the determination unit 132b determines whether or not the value of the motor drive voltage V detected in the process of step S6 is less than a predetermined threshold value Vth. As a result of the determination, when the motor drive voltage V is less than the predetermined threshold Vth (step S7: Yes), the determination unit 132b advances the compression stroke determination process to the process of step S11. On the other hand, when the motor drive voltage V is greater than or equal to the predetermined threshold Vth (step S7: No), the determination unit 132b advances the compression stroke determination process to the process of step S8. As the predetermined threshold voltage Vth, for example, a value (V3 × K) obtained by multiplying the minimum battery voltage V3 at the compression top dead center at the start time obtained by experiment by a correction coefficient K corresponding to the water temperature or the battery voltage, Alternatively, a value (V3−K ′) obtained by subtracting the correction coefficient K ′ from the minimum battery voltage V3 can be used.

  In the process of step S8, the control unit 132 acquires the current time t based on the count value of the timer 134. Thereby, the process of step S8 is completed, and the compression stroke determination process proceeds to the process of step S9.

  In the process of step S9, the control unit 132 calculates an elapsed time T1 (= t−T0) from the reverse rotation start time T0 to the current time t acquired in the process of step S8. Thereby, the process of step S9 is completed and the compression stroke determination process proceeds to the process of step S10.

  In the process of step S10, the determination unit 132b determines whether or not the elapsed time T1 calculated in the process of step S9 is less than a predetermined time. As a result of the determination, when the elapsed time T1 is less than the predetermined time (step S10: Yes), the determination unit 132b returns the compression stroke determination process to the process of step S3. On the other hand, when the elapsed time T1 is equal to or longer than the predetermined time (step S10: No), the determination unit 132b advances the compression stroke determination process to the process of step S11.

  In the process of step S11, the determination unit 132b detects the current rotation angle (current crank position) of the crankshaft via the crank angle sensor 103 (time shown in FIGS. 3A and 3B). t = T1), it is determined that the detected current crank position is the compression top dead center. When the motor drive voltage V lower than the predetermined threshold voltage Vth cannot be detected within a predetermined time, the determination unit 132b may determine that the reverse rotation operation has started from the compression top dead center. Thereby, the process of step S11 is completed, and the compression stroke determination process proceeds to the process of step S12.

  In the process of step S12, the control unit 132 ends the reverse rotation operation of the crankshaft of the engine by stopping the driving of the three-phase AC generator 110. Thereby, the process of step S12 is completed and a series of this compression process determination process is complete | finished.

  In this embodiment, compression is performed by a combination of the crankshaft rotation angle (crank position) based on the crank pulse signal of the crank angle sensor 103 and the voltage fluctuation of the lead battery 101 based on the output signal of the voltage sensor 102. The dead point may be determined separately from the exhaust top dead center. Specifically, attention may be paid to the voltage near the exhaust top dead center and the voltage near the compression top dead center, and the lower one of these voltages may be determined as the compression top dead center.

  As is clear from the above description, in the electronic control device 100 according to the present embodiment, the determination unit 132b of the lead battery 101 detected by the voltage detection unit 132a after the three-phase AC generator 110 starts driving the crankshaft. When the voltage becomes lower than the predetermined threshold Vth, a compression stroke determination is performed to determine that the engine stroke is in the compression stroke, and the control unit 132 starts driving the crankshaft by the three-phase AC generator 110. Since the duty for driving the three-phase AC generator 110 is controlled so that the voltage of the lead battery 101 is maintained at a predetermined threshold value Vth or more during the period from the determination unit 132b to the determination of the compression stroke, It is possible to determine the compression stroke of the engine with a simple configuration. In addition, it is not necessary to store data such as a map according to the power supply voltage and temperature conditions, and the memory capacity can be reduced. In addition, since the compression stroke of the engine can be determined even in a processing cycle with a low processing priority, it is not necessary to increase the load of a task with a high processing priority that is synchronized with a crank pulse. In addition, since the crank position detection signal is not used, it is possible to determine the compression stroke of the engine regardless of the detection accuracy of the crank position. Further, it is possible to eliminate erroneous determination of the compression top dead center due to the drop of the power supply voltage at the start of the reverse rotation operation.

  Further, in the electronic control apparatus 100 according to the present embodiment, the control unit 132 gradually increases the duty to a predetermined value, so that it is possible to more reliably determine the compression stroke of the engine with a simple configuration.

  Further, in the electronic control apparatus 100 according to the present embodiment, the determination unit 132b starts at the time when the three-phase AC generator 110 starts driving, and the voltage of the lead battery 101 becomes less than the predetermined threshold value Vth within a predetermined time. Since the engine stroke is determined to be in the compression stroke, the compression stroke of the engine can be determined more reliably and practically with a simple configuration.

  Further, in the electronic control device 100 according to the present embodiment, the three-phase AC generator 110 is controlled to rotate the crankshaft in the direction opposite to that during engine operation. It is possible to determine the compression stroke of the engine and contribute to a more reliable engine start.

  In addition, since the electronic control apparatus 100 according to the present embodiment targets an engine that is a single-cylinder internal combustion engine, the compression stroke of the engine can be more reliably determined with a simple configuration. .

  It should be noted that the present invention is not limited to the above-described embodiments in terms of the type, arrangement, number, etc. of the constituent elements, and departs from the gist of the invention, such as appropriately replacing such constituent elements with those having the same operational effects. Of course, it can be appropriately changed within the range not to be.

  As described above, the present invention can provide an electronic control device capable of determining the compression stroke of an engine with a simple configuration. Due to its universal character, the electronic control device for a vehicle such as a motorcycle is provided. It is expected to be widely applicable to control devices.

DESCRIPTION OF SYMBOLS 100 ... Electronic control apparatus 101 ... Lead battery 102 ... Voltage sensor 103 ... Crank angle sensor 110 ... Three-phase alternating current generator 130 ... ECU
131 ... AC / DC converter 132 ... control unit 132a ... voltage detection unit 132b ... determination unit 133 ... memory 134 ... timer

Claims (5)

In an electronic control device including a voltage detection unit that detects a voltage of a battery that supplies electric power to an electric motor that is driven to rotate a crankshaft of an engine that is an internal combustion engine,
Compression that determines that the stroke of the engine is in the compression stroke when the voltage of the battery detected by the voltage detector becomes less than a predetermined threshold after the electric motor starts the driving of the crankshaft. A determination unit for determining a stroke;
The battery voltage is continuously maintained at the predetermined threshold value or more in a period from when the electric motor starts to drive the crankshaft until the determination unit determines the compression stroke. A control unit for controlling a duty for driving the electric motor;
An electronic control device comprising:   The electronic control device according to claim 1, wherein the control unit gradually increases the duty to a predetermined value.   The determination unit determines that the engine stroke is in the compression stroke when the voltage of the battery becomes less than the predetermined threshold within a predetermined time from the time point when the electric motor starts the driving. The electronic control device according to claim 1, wherein the electronic control device is determined.   The electronic control apparatus according to claim 1, wherein the driving of the electric motor rotates the crankshaft in a direction opposite to that during operation of the engine.   The electronic control device according to claim 1, wherein the engine is a single-cylinder internal combustion engine.

Images