JP4145126B2 - Motor control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motor control device capable of controlling regenerative braking of an electric motor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a bicycle with an electric motor that assists a driving force by human power by mounting an electric motor and a battery serving as a power source of the electric motor on a bicycle body that can be driven by human power is known.
FIG. 24 shows a schematic configuration of a bicycle with an electric motor. As shown, an electric motor (2) and a battery (3) as a power source of the motor are mounted on the bicycle body (1). Torque generated by depressing the pedal of the bicycle body (1) is detected by the torque sensor (11), and the detection signal is input to the controller (7). In the controller (7), a torque command corresponding to the input torque detection signal is created and supplied to the electric motor (2). As a result, the bicycle main body (1) is supplied with a motor output torque having a magnitude corresponding to the human power torque value in addition to the human power, thereby assisting the driving force by the human power.
[0003]
In recent years, as an electric motor-equipped bicycle, development of an electric motor-equipped bicycle capable of setting a regenerative travel mode in which the electric motor is in a regenerative braking state has been underway (see, for example, Patent Document 1).
The regenerative travel mode is set when traveling on a downhill, and when the mode is set, the bicycle main body is decelerated by applying a regenerative braking force by the electric motor to the bicycle main body, and the electric motor is used as a generator. By performing the operation, electric power generated from the electric motor is supplied to the battery. In this way, effective use of electric power is achieved.
[0004]
FIG. 25 shows an example of the electrical configuration of a bicycle with an electric motor capable of setting the regenerative travel mode.
In the normal assist driving mode set when driving on flat ground or uphill, the DC power from the battery (3) is converted into AC power by the inverter (72), and the AC power is supplied to the electric motor (2). Then, the motor (2) is driven.
As the electric motor (2), for example, a brushless motor is adopted, and three position signals obtained from three Hall elements (not shown) provided in the electric motor (2) are the rotation speed / rotation position detection circuit (73). To be supplied. The rotation speed / rotation position detection circuit (73) detects the rotation speed and rotation position of the electric motor (2) based on the three position signals, and supplies the results to the control circuit (71).
The torque generated by stepping on the pedal is detected by the human torque sensor (11), and the magnitude of the output current of the electric motor (2) is detected by the motor current detection circuit (5). Is supplied to the control circuit (71).
In the control circuit (71), a PWM control signal is created based on the rotation speed detection signal, the human torque detection signal and the motor current detection signal supplied as described above, and the PWM control signal is supplied to the inverter (72). .
[0005]
On the other hand, in the regenerative travel mode, AC power generated from the electric motor (2) is supplied to the inverter (72), converted into DC power by the inverter (72), boosted and supplied to the battery (3). The
The magnitude of the current flowing into the battery (3) is detected by the regenerative current detection circuit (50), and this result is supplied to the control circuit (71) and the detection result of the rotation speed / rotation position detection circuit (73) is It is supplied to the control circuit (71).
In the control circuit (71), a PWM control signal is created based on the regenerative current detection signal, the rotation speed detection signal, and the rotation position detection signal supplied as described above, and the PWM control signal is supplied to the inverter (72). .
[0006]
The control circuit (71) is connected to the brake lever (12) and the input / output device (13). The input / output device (13) includes various operation switches (not shown) and a display unit (not shown) for displaying the remaining amount of the battery (3).
[0007]
The inverter 72 includes a pair of positive and negative series lines 72 a and 72 a connected to both ends of the battery 3, and these series lines 72 a and 72 a have four parallel lines 72 b ) (72b) (72b) (72b). Each of the three parallel lines includes two switching elements connected in series with each other, and one capacitor C intervenes in one parallel line. The switching elements S1 to S6 are composed of a diode and a transistor, and are on / off controlled by a PWM control signal from the control circuit (71).
Three current lines (72c) (72c) (72c) are connected to the connection point of the switching elements S1 and S2, the connection point of the switching elements S3 and S4, and the connection point of the switching elements S5 and S6. The ends of these current lines are connected to the U-phase winding, V-phase winding, and W-phase winding of the electric motor (2). The motor current detection circuit (5) is interposed in the current line (72c) extending from the connection point between the switching element S1 and the switching element S2.
[0008]
FIG. 26 (a) shows the voltage waveform of the three-phase winding of the electric motor (2) in the regenerative travel mode. Each voltage waveform changes into a sine wave shape with 360 degrees as one cycle, and three voltage waveforms. Have a phase difference of 120 degrees from each other.
FIG. 4B shows the on / off state of the PWM control of the switching elements S1, S3, and S5 in the regenerative travel mode. Each switching element is shifted in timing with respect to each other as shown in the figure. Set to Note that the switching elements S2, S4, and S6 are always set to off.
[0009]
For example, in the section T1 shown in FIG. 5B where the switching element S1 is PWM-controlled, the voltage of the U-phase winding is the lowest and the voltage of the W-phase winding is the highest, so that the switching elements S1 and S2 The step-up chopper circuit shown in FIG. 27 is configured by the diode D2, the U-phase winding, the W-phase winding, and the capacitor C. In such a section, when the switching element S1 is on, current flows from the W-phase winding to the U-phase winding due to the potential difference Euw between the U-phase winding and the W-phase winding, and energy is stored in both windings. On the other hand, when the switching element S1 is off, the energy stored in the U-phase winding and the W-phase winding is supplied to the battery (3).
FIG. 28 shows the ON / OFF state of the switching element S1 and the waveform of the current flowing through the U-phase winding. In the state where the switching element S1 is set to ON, energy is applied to the U-phase winding as described above. Is accumulated, the current flowing through the U-phase winding gradually increases as shown in FIG. On the other hand, in the state where the switching element S1 is set to OFF, the energy stored in the U-phase winding is supplied to the battery, so that the current flowing through the U-phase winding gradually decreases as shown in FIG. Small.
[0010]
Next, in the section T2 shown in FIG. 26B, the voltage of the U-phase winding is the lowest and the voltage of the V-phase winding is the highest, so the switching element S1, the diode of the switching element S2, the U-phase winding, A step-up chopper circuit is configured by the V-phase winding and the capacitor C. In such a section, when the switching element S1 is on, current flows from the V-phase winding to the U-phase winding due to the potential difference between the V-phase winding and the U-phase winding, and energy is stored in both windings. On the other hand, when the switching element S1 is off, the energy stored in the U-phase winding and the V-phase winding is supplied to the battery (3).
Thereafter, in the section T3 in which the switching element S3 is PWM-controlled, the voltage of the W-phase winding is the lowest and the voltage of the V-phase winding is the highest, so the switching element S3, the diode of the switching element S4, the V-phase winding, The W-phase winding and the capacitor C constitute a boost chopper circuit. In such a section, when the switching element S3 is on, a current flows from the V-phase winding to the W-phase winding due to the potential difference between the V-phase winding and the W-phase winding, and energy is stored in both windings. On the other hand, when the switching element S3 is off, the energy stored in the V-phase winding and the W-phase winding is supplied to the battery (3).
[0011]
In the bicycle with an electric motor having the inverter (72) shown in FIG. 25, as described above, the PWM is controlled for the switching elements S1, S3, and S5, and energy is stored in each winding of the electric motor and the winding is stored in each winding. The operation of supplying the energy to the battery is repeated, whereby the battery (3) is charged.
[0012]
[Patent Document 1]
JP 2000-6878 A
[Patent Document 2]
Japanese Patent Laid-Open No. 2002-19985
[0013]
[Problems to be solved by the invention]
However, according to the applicant's research, it has been found that a sufficiently high regeneration efficiency cannot be obtained in a conventional bicycle with an electric motor capable of setting the regeneration running mode.
The objective of this invention is providing the motor control apparatus which can obtain regeneration efficiency higher than before.
[0014]
[Means for solving the problems]
The applicant has investigated the reason why a sufficiently high regeneration efficiency cannot be obtained in a conventional bicycle with an electric motor as follows.
If the ratio (PWM duty) of the on period Ton to the switching period T becomes excessive, the off period Toff becomes extremely shorter than the on period Ton, so that the energy released from the winding in the off period Toff is the electric motor in the on period Ton. The energy generated from the electric motor during the on-period Ton is increased and the loss energy consumed without being stored in the winding increases. FIG. 29 shows the relationship between the PWM duty, the electric power generated from the electric motor, and the regenerative electric power supplied to the battery, and the electric power generated from the electric motor increases as the PWM duty increases, as indicated by a one-dot chain line. is doing. On the other hand, as shown by the solid line, the regenerative power supplied to the battery increases as the PWM duty increases. After reaching the peak, the regenerative power decreases rapidly and the loss energy increases.
In a conventional bicycle with an electric motor, when the PWM duty exceeds the value at the peak point of the regenerative power as described above, the PWM duty is changed over the entire range of 0 to 100% even though the loss energy increases. A sufficiently high regeneration efficiency cannot be obtained.
[0015]
A motor control device according to the present invention is capable of controlling regenerative braking of an electric motor, and supplies an electric power generated from the electric motor to a battery serving as a power source of the motor, and a PWM control for controlling the inverter With circuit. The motor control device includes speed detection means for detecting the rotation speed of the electric motor, and the PWM control circuit has a peak regenerative power supplied to the battery based on the rotation speed of the electric motor. Limit the value to the value at the point or the vicinity thereof.
[0016]
As described above, the regenerative power supplied to the battery increases as the PWM duty increases, and decreases rapidly after reaching the peak. Here, there is a fixed relationship between the PWM duty at the peak point of the regenerative power and the rotation speed of the electric motor, where the PWM duty at the peak point of the regenerative power decreases as the rotation speed of the electric motor increases. To establish.
Therefore, in the motor control device according to the present invention, the PWM duty is limited to a value at or near the peak value of the regenerative power based on the rotational speed of the electric motor. In this way, by limiting the PWM duty to a value at the peak point of regenerative power, that is, a point at which the loss energy starts to increase, or a value close to it, the loss compared to the conventional configuration in which the PWM duty is changed over the entire range. Energy can be reduced.
[0017]
The motor control device having the first specific configuration includes motor current detection means for detecting the magnitude of the output current of the electric motor. The PWM control circuit calculates a motor current command value representing a target value of the output current of the electric motor, and changes the PWM duty based on the motor current command value and the detection result by the motor current detection means. To execute the process,
Upper limit value deriving means for deriving a motor current command value at or near a point where the regenerative power supplied to the battery peaks based on the rotation speed of the electric motor as a current command upper limit value;
It is determined whether or not the calculated motor current command value exceeds the derived current command upper limit value, and when the calculated current command upper limit value is exceeded, the current command that sets the motor current command value to the upper limit value Value setting means
And has.
[0018]
The PWM duty increases as the motor current command value increases. Therefore, by suppressing the motor current command value to a value at or near the peak value of the regenerative power, the PWM duty can be suppressed to a value at or near the peak point. In addition, between the motor current command value at the peak point of the regenerative power and the rotation speed of the electric motor, the motor current command value at the peak point of the regenerative power increases as the rotation speed of the electric motor increases. A relationship is established.
Therefore, in the above specific configuration, the motor current command value at the peak point of the regenerative power or a value near the motor current command value is derived as the current command upper limit value based on the rotation speed of the electric motor. For example, a table or a functional expression representing the relationship between the rotational speed of the electric motor and the motor current command value at the peak point of the regenerative power or its neighborhood value is stored in the upper limit value deriving means, and the current command upper limit value is It is derived from the rotational speed of the electric motor based on these tables or function expressions.
Thereafter, when the calculated motor current command value exceeds the current command upper limit value derived as described above, the motor current command value is set to the upper limit value, and the set motor current command value and the motor current detection are set. The PWM duty is set based on the motor current value detected by the means. In this way, the PWM duty is limited to a value at or near the peak value of the regenerative power.
[0019]
Specifically, the PWM control circuit changes the step width when changing the PWM duty based on the detection result by the motor current detecting means.
[0020]
For example, in a configuration in which the inverter boosts the electric power generated from the electric motor and supplies it to the battery, the regenerative power supplied to the battery gradually increases as the PWM duty increases, and the inverter duty increases as the PWM duty increases. The step-up ratio increases and the output voltage of the inverter increases rapidly from the point where the voltage across the battery exceeds the voltage across the battery. Further, the output current value of the electric motor increases as the PWM duty increases.
Therefore, in the above specific configuration, for example, when the output current value of the electric motor at a point where the regenerative power change suddenly increases becomes a threshold value, and the motor current value detected by the motor current detection means is smaller than the threshold value, While changing the PWM duty with a large step width, if the motor current value is larger than the threshold value, the PWM duty is changed with a small step width.
In this way, since the PWM duty is changed with a large step width in a range where the regenerative electric power changes slowly, the regenerative braking force starts to be effective as compared with the configuration in which the PWM duty is changed with a small step width over the entire range. Can be shortened.
[0021]
The motor control device having the second specific configuration includes regenerative current detection means for detecting the magnitude of the regenerative current flowing into the battery. The PWM control circuit calculates a regenerative current command value representing a target value of the regenerative current flowing into the battery, and changes the PWM duty based on the regenerative current command value and the detection result by the regenerative current detection means. To execute the process,
An upper limit value deriving means for deriving a regenerative current command value at a point where the regenerative power supplied to the battery reaches a peak or a value near the regenerative power based on the rotation speed of the electric motor as a current command upper limit value;
It is determined whether or not the calculated regenerative current command value exceeds the derived current command upper limit value, and when it exceeds the current command upper limit value, the current command that sets the regenerative current command value to the upper limit value Value setting means
And has.
[0022]
The PWM duty increases as the regenerative current command value increases. Therefore, by suppressing the regenerative current command value to a value at or near the peak value of the regenerative power, the PWM duty can be suppressed to a value at or near the peak point. In addition, between the regenerative current command value at the peak point of the regenerative power and the rotation speed of the electric motor, the regenerative current command value at the peak point of the regenerative power increases as the rotation speed of the electric motor increases. A relationship is established.
Therefore, in the above specific configuration, based on the rotation speed of the electric motor, the regenerative current command value at the peak point of the regenerative power or a value near it is derived as the current command upper limit value. For example, a table or a function expression representing the relationship between the rotational speed of the electric motor and the regenerative current command value at the peak point of the regenerative power or its neighborhood value is stored in the upper limit value deriving means, and the current command upper limit value is It is derived from the rotational speed of the electric motor based on these tables or function expressions.
Thereafter, when the calculated regenerative current command value exceeds the current command upper limit value derived as described above, the regenerative current command value is set to the upper limit value, and the set regenerative current command value and regenerative current detection are set. The PWM duty is set based on the regenerative current value detected by the means. In this way, the PWM duty is limited to a value at or near the peak value of the regenerative power.
[0023]
Specifically, the PWM control circuit changes the step width when changing the PWM duty based on the detection result by the regenerative current detecting means.
[0024]
As described above, in the configuration in which the inverter boosts the electric power generated from the electric motor and supplies it to the battery, the regenerative power supplied to the battery gradually increases as the PWM duty increases and the boost ratio of the inverter increases. Then, the output voltage of the inverter increases rapidly from the point where the voltage across the battery exceeds. In addition, since the regenerative power supplied to the battery is proportional to the amount of regenerative current flowing into the battery, the regenerative current value gradually increases as the PWM duty increases, similarly to the regenerative power, and the boost ratio of the inverter increases. It increases and suddenly increases from the point where the output voltage of the inverter exceeds the voltage across the battery.
Therefore, in the above specific configuration, for example, when the regenerative current value at a point where the change in the regenerative power suddenly increases becomes a threshold value, and the regenerative current value detected by the regenerative current detecting means is smaller than the threshold value, the PWM While the duty is changed with a large step width, when the regenerative current value is larger than the threshold value, the PWM duty is changed with a small step width.
In this way, since the PWM duty is changed with a large step width in a range where the regenerative electric power changes slowly, the regenerative braking force starts to be effective as compared with the configuration in which the PWM duty is changed with a small step width over the entire range. Can be shortened.
[0025]
In the motor control device having the third specific configuration, the PWM control circuit includes:
Upper limit value deriving means for deriving the PWM duty at a point where the regenerative power supplied to the battery reaches a peak based on the rotational speed of the electric motor or a value near the PWM duty as an upper limit value of the PWM duty;
Duty upper limit value setting means for determining whether or not the PWM duty exceeds the derived PWM duty upper limit value, and setting the PWM duty to the upper limit value when the PWM duty upper limit value is exceeded
And has.
[0026]
As described above, a certain relationship is established between the PWM duty at the peak point of the regenerative power and the rotation speed of the electric motor.
Therefore, in the above specific configuration, the PWM duty at the peak point of the regenerative power or a value in the vicinity thereof is derived as the PWM duty upper limit value based on the rotation speed of the electric motor. For example, a table or a function expression representing the relationship between the rotational speed of the electric motor and the PWM duty at the peak point of the regenerative power or its neighborhood value is stored in the upper limit value deriving means, and the PWM duty upper limit value is It is derived from the rotational speed of the electric motor based on a table or a function formula.
Thereafter, when the PWM duty exceeds the duty upper limit value derived as described above, the PWM duty is set to the upper limit value. In this way, the PWM duty is set to a value at or near the peak value of the regenerative power.
[0027]
Specifically, the PWM control circuit is
Lower limit value deriving means for deriving a lower limit value of the PWM duty based on the rotation speed of the electric motor;
Duty lower limit value setting means for determining whether or not the PWM duty is lower than the derived PWM duty lower limit value, and setting the PWM duty to the lower limit value when it is lower than the PWM duty lower limit value
And has.
[0028]
As described above, in the configuration in which the inverter boosts the electric power generated from the electric motor and supplies it to the battery, the regenerative power supplied to the battery gradually increases as the PWM duty increases and the boost ratio of the inverter increases. Then, the output voltage of the inverter increases rapidly from the point where the voltage across the battery exceeds. In addition, between the PWM duty at the point where the change in the regenerative power supplied to the battery suddenly increases and the rotation speed of the electric motor, the change in the regenerative power increases rapidly as the rotation speed of the electric motor increases. A certain relationship is established in which the PWM duty at this point decreases.
Therefore, in the above specific configuration, for example, a value smaller than the PWM duty at a point where the change in regenerative power suddenly increases is a predetermined value as a PWM duty lower limit value, and the lower limit value and the rotation speed of the electric motor are A table or function expression representing the above relationship is stored in the lower limit value deriving means, and the PWM duty lower limit value is derived from the rotational speed of the electric motor based on these tables or function expressions.
Thereafter, when the PWM duty is below the PWM duty lower limit value derived as described above, the PWM duty is set to the lower limit value. In this way, the PWM duty increases from the derived PWM duty lower limit value. Therefore, the time until the regenerative braking force starts to be effective can be shortened as compared with the configuration in which the PWM duty is increased from zero.
[0029]
The motor control device according to the present invention can control regenerative braking of an electric motor, and controls an inverter that supplies electric power generated from the electric motor to a battery serving as a power source of the motor. And a PWM control circuit. The motor control device includes regenerative current detection means for detecting the magnitude of the regenerative current flowing into the battery, and the PWM control circuit is supplied with PWM duty to the battery based on the detection result by the regenerative current detection means. The regenerative power is limited to a value at a point where the regenerative power reaches a peak or a value close to the value.
[0030]
A fixed relationship is established between the PWM duty at the peak point of the regenerative power and the magnitude of the regenerative current flowing into the battery, such that the PWM duty at the peak point of the regenerative power decreases as the regenerative current increases.
Therefore, in the motor control device according to the present invention, the PWM duty is limited to a value at the peak point of the regenerative power or a value close to the PWM duty based on the regenerative current value detected by the regenerative current detecting means. In this way, by limiting the PWM duty to a value at the peak point of regenerative power, that is, a point at which the loss energy starts to increase, or a value close to it, the loss compared to the conventional configuration in which the PWM duty is changed over the entire range. Energy can be reduced.
[0031]
Specifically, the PWM control circuit is
An upper limit value deriving unit for deriving a PWM duty at a point where the power supplied to the battery reaches a peak or a value near the PWM duty based on a detection result by the regenerative current detecting unit;
Duty upper limit value setting means for determining whether or not the PWM duty exceeds the derived PWM duty upper limit value, and setting the PWM duty to the upper limit value when the PWM duty upper limit value is exceeded
And has.
[0032]
As described above, a certain relationship is established between the PWM duty at the peak point of the regenerative power and the magnitude of the regenerative current flowing into the battery.
Therefore, in the above specific configuration, the PWM duty at the peak point of the regenerative power or a value in the vicinity thereof is derived as the PWM duty upper limit value based on the regenerative current value detected by the regenerative current detecting means. For example, a table or a function expression representing the relationship between the regenerative current value and the PWM duty at the peak point of the regenerative power is stored in the upper limit value deriving means, and the PWM duty upper limit value is based on these tables or function expressions. It is derived from the detection result by the regenerative current detection means.
Thereafter, when the PWM duty exceeds the PWM duty upper limit value derived as described above, the PWM duty is set to the upper limit value. In this way, the PWM duty is limited to a value at or near the peak value of the regenerative power.
In the motor control device, since the PWM duty upper limit value is derived from the regenerative current value, it is not necessary to equip the rotation speed detecting means for deriving the PWM duty upper limit value from the rotation speed of the electric motor.
[0033]
【The invention's effect】
According to the motor control device of the present invention, by limiting the PWM duty to a value at or near the peak value of the regenerative power, it is possible to obtain higher regenerative efficiency than before.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the embodiment in which the present invention is applied to a bicycle with an electric motor will be specifically described with reference to the drawings.
First embodiment
FIG. 1 shows a schematic configuration of a bicycle with an electric motor according to the present invention. A bicycle body (1) is equipped with an electric motor (2) and a battery (3) as a power source of the motor.
The electric motor-equipped bicycle can switch a traveling mode between a normal assist traveling mode and a regenerative traveling mode in which the electric motor (2) is set to a regenerative braking state. Torque generated by depressing the pedal of the main body (1) is detected by the human power torque sensor (11), and the detection signal is input to the controller (4). In the controller (4), a torque command corresponding to the input torque detection signal is created and supplied to the electric motor (2). As a result, the bicycle main body (1) is supplied with a motor output torque having a magnitude corresponding to the human power torque value in addition to the human power, thereby assisting the driving force by the human power.
On the other hand, in the regenerative running mode, the bicycle main body (1) is decelerated by applying a regenerative braking force by the electric motor (2) to the bicycle main body (1), and the electric motor (2) operates as a generator. By doing so, the electric power generated from the electric motor (2) is supplied to the battery (3).
[0035]
FIG. 2 shows an electrical configuration of the electric motor-equipped bicycle.
In the assist travel mode, DC power from the battery (3) is converted into AC power by the inverter (42), and the AC power is supplied to the electric motor (2) to drive the motor (2).
A brushless motor is adopted as the electric motor (2), and three position signals obtained from three Hall elements (not shown) provided in the motor (2) are the rotational speed / rotational position detection circuit (43). To be supplied. The rotational speed / rotational position detection circuit (43) detects the rotational speed and rotational position of the electric motor (2) based on the three position signals, and supplies the results to the control circuit (41).
The torque generated by depressing the pedal is detected by the human-powered torque sensor (11), and the magnitude of the output current of the electric motor (2) is detected by the motor current detection circuit (5). Is supplied to the control circuit (41).
In the control circuit (41), a PWM control signal is created based on the rotation speed detection signal, the human torque detection signal and the motor current detection signal supplied as described above, and the PWM control signal is supplied to the inverter (42). .
[0036]
On the other hand, in the regenerative travel mode, AC power generated from the electric motor (2) is supplied to the inverter (42), converted into DC power by the inverter (42), boosted and supplied to the battery (3). The
The control circuit (41) is supplied with the detection result of the motor current detection circuit (5) and the detection result of the rotation speed / rotation position detection circuit (43), and a PWM control signal is created based on these detection results. To the inverter (42).
[0037]
Also, the brake lever (12) is connected to the control circuit (41), and the assist travel mode is set when the brake lever (12) is not operated, while the brake lever (12 ), The regenerative travel mode is set.
Further, an input / output device (13) is connected to the control circuit (41), and the input / output device (13) displays various operation switches (not shown) and the remaining amount of the battery (3). For display (not shown).
[0038]
The inverter (42) has the same configuration as the conventional inverter (72) shown in FIG. 25, and is composed of six switching elements S1 to S6 composed of diodes and transistors and a capacitor C. Yes. These six switching elements S1 to S6 are on / off controlled by a PWM control signal from the control circuit (41).
[0039]
FIG. 3 shows a control procedure executed by the control circuit (41) during traveling.
When the power supply of the bicycle body is turned on, first, in step S1, the travel mode is set to the assist travel mode, and the motor current command value indicating the target value of the output current of the electric motor and the PWM duty are set to zero. To do.
Next, when traveling is started in step S2, it is determined in step S3 whether or not the brake lever (12) is being operated. Here, if the operation is not performed on the brake lever (12), it is determined as no and the process proceeds to step S4, where it is determined whether or not the output value of the human torque sensor (11) is zero. To do. If it is determined NO, the motor current command value is calculated based on the output value of the human torque sensor (11) and the output value of the rotation speed / rotation position detection circuit (43) in step S5. The PWM duty is increased or decreased by comparing the motor current command value with the output value of the motor current detection circuit (5). On the other hand, if it is determined YES in step S4, the motor current command value is set to zero in step S6, and then the motor current command value is compared with the output value of the motor current detection circuit (5). Reduce the PWM duty.
In step S7, a PWM control signal corresponding to the PWM duty obtained in step S5 or step S6 is created, and the PWM control signal is supplied to the inverter (42). Thereafter, in step S8, it is determined whether or not the rotational speed detected by the rotational speed / rotational position detection circuit (43) is zero. If it is determined NO, the process returns to step S3.
[0040]
If the brake lever (12) is being operated, it is determined YES in step S3, the travel mode is set to the regenerative travel mode, and then the process proceeds to step S9. Is increased or decreased. Subsequently, in step S10, a PWM control signal corresponding to the PWM duty obtained in step S9 is created, and the PWM control signal is supplied to the inverter (42).
Thereafter, when the rotational speed becomes zero, it is determined as YES in step S8, the traveling is stopped in step S11, and the procedure is terminated.
According to the above procedure, when the brake lever (12) is not operated, the assist travel mode is set, and a driving force having a magnitude corresponding to the human power torque value is applied to the bicycle body to assist the driving force by human power. On the other hand, when the brake lever (12) is operated, the regenerative travel mode is set, the regenerative braking force is applied to the bicycle body, and the bicycle body is decelerated.
[0041]
By the way, the regenerative power supplied to the battery gradually increases as the PWM duty increases as shown by a solid line in FIG. 4, and decreases rapidly after reaching the peak.
Therefore, in the bicycle with an electric motor according to the present invention, when the regenerative travel mode is set, the PWM duty is limited to a value equal to or less than the value at the peak point P of the regenerative power.
Further, the PWM duty increases as the motor current command value increases, as indicated by a one-dot chain line in FIG. Here, when the rotation speed of the electric motor is ω2, the motor current command value Im2 at the peak point P of the regenerative power is larger than the value Im1 when the rotation speed is ω1 (ω1 <ω2). As shown in FIG. 5, the motor at the peak point of the regenerative power is increased between the rotation speed of the electric motor and the motor current command value at the peak point P of the regenerative power. A certain relationship in which the current command value increases is established.
Therefore, with the motor current command value at the peak point of the regenerative power as an upper limit value, a motor current command upper limit value table representing the relationship between the rotation speed of the electric motor and the upper limit value is stored in the built-in memory (illustrated) of the control circuit (41). (Omitted). Then, an upper limit value of the motor current command value is derived from the number of rotations of the electric motor based on the table, and the motor current command value is limited to a value equal to or less than the upper limit value. In the example shown in FIG. 4, when the rotation speed of the electric motor is ω1, the PWM duty can be suppressed to α1 or less by suppressing the motor current command value to Im1 or less, and when the rotation speed is ω2, the motor current By suppressing the command value to Im2 or less, the PWM duty can be suppressed to α2 or less.
In this way, the loss energy can be reduced by limiting the PWM duty to a value equal to or less than the value at the peak point P of the regenerative power, and as a result, high regenerative efficiency can be obtained.
[0042]
In the bicycle with an electric motor according to the present invention, the step width for increasing the PWM duty is set based on the output current value of the electric motor.
The regenerative power supplied to the battery gradually increases as the PWM duty increases as shown by the solid line in FIG. 4, and the boost voltage ratio of the inverter increases and the inverter output voltage exceeds the voltage across the battery. In the example shown in the figure, the PWM duty increases rapidly from the point T at which the PWM duty becomes about 70%. Further, the output current value of the electric motor increases as the PWM duty increases.
Therefore, using the output current value of the electric motor when the PWM duty is about 70% as a threshold value, two values Δ1 and Δ2 having a magnitude different from the threshold value are built-in memory (not shown) of the control circuit (41). Stored in When the output current value of the electric motor is less than or equal to the threshold value, the step width Δ is set to the larger value Δ1 of the two values, while the output current value of the electric motor exceeds the threshold value. In this case, the step Δ is set to the smaller value Δ2.
In this manner, by setting the step width Δ to a large value Δ1 in a range where the regenerative electric power change is moderate, the regenerative braking force starts to be effective as compared with the configuration in which the step width Δ is always set to a small value Δ2. Time can be shortened.
[0043]
Furthermore, in the bicycle with an electric motor according to the present invention, the lower limit value of the PWM duty is derived based on the rotation speed of the electric motor, and the PWM duty is set to a value equal to or higher than the lower limit value.
As indicated by the solid line in FIG. 4, when the rotational speed of the electric motor is ω2, the PWM duty β2 at the point T at which the regenerative power change suddenly increases is the value when the rotational speed ω1 (ω1 <ω2). As shown in FIG. 6, the rotational speed of the electric motor increases between the PWM duty at the point where the rotational speed of the electric motor and the change in the regenerative power suddenly increase. As a result, a constant relationship is established in which the PWM duty increases at the point where the change in the regenerative power increases rapidly.
Therefore, a PWM duty lower limit value table that represents the relationship between the rotation speed of the electric motor and the lower limit value, with a value smaller than the PWM duty at a point where the change in regenerative power suddenly increases as a lower limit value. It is stored in a built-in memory (not shown) of the control circuit (41). Then, a lower limit value of the PWM duty is derived from the rotation speed of the electric motor based on the table, and the PWM duty is increased from the lower limit value. As a result, the time until the regenerative braking force starts to be effective can be shortened as compared with the configuration in which the PWM duty is increased from 0%.
[0044]
FIG. 7 shows the PWM duty change procedure in step S9 of FIG. 3 executed in the regenerative travel mode.
First, in step S21, a motor current command value is calculated based on the output value of the rotation speed / rotation position detection circuit (43) and the output value of the motor current detection circuit (5), and then in step S22, the rotation speed. / The output value of the rotation position detection circuit (43) and the output value of the motor current detection circuit (5) are acquired, and in step S23, the motor current command value is limited to a value below the peak value of the regenerative power, which will be described later Execute.
[0045]
Subsequently, in step S24, it is determined whether or not the motor current value acquired in step S22 is greater than or equal to the motor current command value. If NO is determined, the process proceeds to step S25 to increase the PWM duty. Set the step width. Thereafter, in step S26, a procedure for setting the PWM duty to a value equal to or higher than the lower limit value corresponding to the rotation speed of the electric motor is executed. In step S27, the procedure is executed by increasing the PWM duty by the set step width. finish. Specific procedures of step S25 and step S26 will be described later.
On the other hand, if the motor current value acquired in step S22 is equal to or greater than the motor current command value and it is determined yes in step S24, the process proceeds to step S28, and the PWM duty is reduced by a predetermined step width. Let's finish and finish the procedure.
[0046]
FIG. 8 shows the motor current command value limiting procedure in step S23. First, in step S31, based on the motor current command upper limit value table stored in the built-in memory, the upper limit value of the motor current command value is derived from the rotation speed acquired in step S22 of FIG. Next, in step S32, it is determined whether or not the motor current command value calculated in step S21 of FIG. 7 is greater than or equal to the derived upper limit value. If it is determined no, the procedure is terminated.
On the other hand, if the motor current command value is equal to or greater than the derived upper limit value and it is determined YES in step S32, the process proceeds to step S33, and the motor current command value is set to the upper limit value. End the procedure.
By the above procedure, the motor current command value is set to a value equal to or less than the value at the peak point of the regenerative power.
[0047]
FIG. 9 shows the PWM duty step width setting procedure in step S25 of FIG.
First, in step S34, it is determined whether or not the motor current value acquired in step S22 of FIG. 7 is equal to or greater than the threshold value stored in the built-in memory. If NO is determined, the process proceeds to step S35. The step width Δ when increasing the PWM duty is set to the larger value Δ1 of the two values Δ1 and Δ2 stored in the built-in memory, and the procedure is terminated.
On the other hand, if the motor current value acquired in step S22 of FIG. 7 is equal to or greater than the threshold value and it is determined yes in step S34, the process proceeds to step S36, and the two values Δ1, Δ2 are set. The smaller value Δ2 is set, and the procedure is terminated.
If the output current value of the electric motor is below the threshold value according to the above procedure, the PWM duty step width is set to a large value, while if the output current value of the electric motor is equal to or greater than the threshold value, the PWM duty is set. The step width is set to a small value.
[0048]
FIG. 10 shows the PWM duty lower limit value setting procedure in step S26 of FIG.
First, in step S37, the lower limit value of the PWM duty is derived from the rotational speed acquired in step S22 of FIG. 7 based on the PWM duty lower limit value table stored in the built-in memory. Next, in step S38, it is determined whether or not the current PWM duty is below the derived lower limit value. If it is determined NO, the procedure is terminated.
On the other hand, if the PWM duty is lower than the derived lower limit value and it is determined as YES in step S38, the process proceeds to step S39 to set the PWM duty to the lower limit value and perform the procedure. finish.
According to the above procedure, the PWM duty increases from the lower limit value corresponding to the rotation speed of the electric motor.
[0049]
In the bicycle with an electric motor of this embodiment, the PWM duty is limited to a value equal to or less than the value at the peak point of the regenerative power as described above, so that the loss energy is reduced, and as a result, high regeneration efficiency can be obtained.
Further, since the step width Δ when changing the PWM duty is set to a large value Δ1 in a range where the change in the regenerative power is moderate, the regenerative braking force is larger than the configuration in which the step width Δ is always set to a small value Δ2. Time to start working is shortened.
Furthermore, since the PWM duty is increased from the lower limit value according to the rotation speed of the electric motor, the time until the regenerative braking force starts to be effective is shortened compared to the configuration in which the PWM duty is increased from 0%.
[0050]
Second embodiment
In the electric bicycle with an electric motor of the first embodiment, the motor duty command value is compared with the output current value of the electric motor when the regenerative travel mode is set, whereas the PWM duty is changed. The bicycle with an electric motor of this embodiment changes the PWM duty by comparing the regenerative current command value representing the target value of the regenerative current flowing into the battery (3) with the regenerative current input to the battery. As shown in FIG. 11, a regenerative current detection circuit (50) for detecting the magnitude of the regenerative current flowing into the battery (3) is provided between the battery (3) and the inverter (42).
[0051]
The solid line in FIG. 12 represents the relationship between PWM duty and regenerative power, and the alternate long and short dash line in FIG. 12 represents the relationship between regenerative current command value and PWM duty.
The PWM duty increases as the regenerative current command value increases and reaches discontinuity at the peak point of the regenerative power and reaches 100%, as indicated by the alternate long and short dash line in FIG. As described above, the reason why the PWM duty reaches 100% at the peak of the regenerative power is that when the regenerative power reaches the peak, the magnitude of the regenerative current input to the battery does not reach the regenerative current command value. This is because it continues to increase. As shown in the figure, when the rotational speed of the electric motor is ω2, the regenerative current command value Ib2 at the peak point P of the regenerative power is larger than the value Ib1 when the rotational speed is ω1 (ω1 <ω2). As shown in FIG. 13, between the rotation speed of the electric motor and the regenerative current command value at the regenerative power peak point P, the regenerative power peak point increases as the rotation speed of the electric motor increases. A certain relationship is established in which the regenerative current command value increases.
Therefore, in the bicycle with an electric motor of the present embodiment, a regenerative current command upper limit value table representing the relationship between the rotation speed of the electric motor and the upper limit value with the regenerative current command value at the peak point of the regenerative power as an upper limit value. It is stored in a built-in memory (not shown) of the control circuit (61). Then, the upper limit value of the regenerative current command value is derived from the number of rotations of the electric motor based on the table, and the regenerative current command value is set to a value equal to or lower than the upper limit value. In the example shown in FIG. 12, when the rotation speed is ω1, the PWM duty can be suppressed to α1 or less by suppressing the regenerative current command value to Ib1 or less. When the rotation speed is ω2, the regenerative current command value is set to The PWM duty can be suppressed to α2 or less by suppressing it to Ib2 or less.
[0052]
Further, the regenerative power supplied to the battery gradually increases as the PWM duty increases as shown by the solid line in FIG. 12, and rapidly increases from the point where the PWM duty becomes about 70%. In addition, since the regenerative power supplied to the battery is proportional to the amount of regenerative current flowing into the battery, the regenerative current value gradually increases as the PWM duty increases, and the PWM duty increases as the regenerative power changes. It increases rapidly from the point where it becomes about 70%.
Therefore, in the bicycle with an electric motor of the present embodiment, the regenerative current value when the PWM duty is about 70% is set as a threshold value, and two values Δ1 and Δ2 having different sizes from the threshold value are controlled by the control circuit (61). Is stored in a built-in memory (not shown). When the regenerative current value is less than or equal to the threshold value, the step width Δ is set to the larger value Δ1 of the two values, whereas when the regenerative current value exceeds the threshold value, the step Δ is The smaller value Δ2 is set.
[0053]
In the bicycle with an electric motor according to the present embodiment, the control procedure similar to that shown in FIG. Here, since the control procedure executed by the control circuit (61) is the same except for the PWM duty change procedure in step S9, the entire description is omitted.
[0054]
FIG. 14 shows a PWM duty change procedure executed by the control circuit (61) of this embodiment.
First, in step S41, a regenerative current command value is calculated based on the output value of the rotational speed / rotational position detection circuit (43) and the output value of the regenerative current detection circuit (50), and then in step S42, the rotational speed. / The output value of the rotational position detection circuit (43) and the output value of the regenerative current detection circuit (50) are acquired, and in step S43, the regenerative current command value is limited to a value below the peak value of the regenerative power, which will be described later. Execute.
[0055]
Subsequently, in step S44, it is determined whether or not the regenerative current value acquired in step S42 is greater than or equal to the regenerative current command value. If NO is determined, the process proceeds to step S45 to increase the PWM duty. A procedure described later for setting the step width when performing the processing is executed. Thereafter, in step S46, a procedure for setting the PWM duty to a value equal to or higher than the lower limit value corresponding to the rotational speed of the electric motor is executed. In step S47, the procedure is executed by increasing the PWM duty by the set step width. finish. Note that the procedure of step S46 is the same as the procedure shown in FIG.
On the other hand, if the regenerative current value is greater than or equal to the regenerative current command value and it is determined YES in step S44, the process proceeds to step S48, where the PWM duty is reduced by a predetermined step width and the procedure is terminated. To do.
[0056]
FIG. 15 shows the regenerative current command value limiting procedure in step S43. First, in step S51, the upper limit value of the regenerative current command value is derived from the rotation speed acquired in step S42 of FIG. 14 based on the regenerative current command upper limit value table stored in the built-in memory. Next, in step S52, it is determined whether or not the regenerative current command value calculated in step S41 of FIG. 14 is greater than or equal to the derived upper limit value. If it is determined no, the procedure ends.
On the other hand, when the regenerative current command value is equal to or greater than the derived upper limit value and it is determined as YES in step S52, the process proceeds to step S53, and the regenerative current command value is set to the upper limit value. End the procedure.
By the above procedure, the regenerative current command value is set to a value equal to or less than the value at the peak point of the regenerative power.
[0057]
FIG. 16 shows the PWM duty step width setting procedure in step S45 of FIG.
First, in step S54, it is determined whether or not the regenerative current value acquired in step S42 of FIG. 14 is equal to or greater than the threshold value stored in the built-in memory. If NO is determined, the process proceeds to step S55. The step width Δ when increasing the PWM duty is set to the larger value Δ1 of the two values Δ1 and Δ2 stored in the built-in memory, and the procedure is terminated.
On the other hand, if the regenerative current value is equal to or greater than the threshold value and it is determined as YES in step S54, the process proceeds to step S56, and the smaller value Δ2 is set out of the two values Δ1 and Δ2. To finish the procedure.
When the regenerative current value is below the threshold value according to the above procedure, the PWM duty step width is set to a large value, while when the regenerative current value is equal to or greater than the threshold value, the PWM duty step width is a small value. Will be set to.
[0058]
Third embodiment
In the bicycle with an electric motor of the first embodiment, the PWM duty is indirectly suppressed below the value at the peak point of the regenerative power by suppressing the motor current command value below the value at the peak point of the regenerative power. On the other hand, the bicycle with an electric motor of this embodiment directly suppresses the PWM duty to a value below the peak value of the regenerative power, and its electrical configuration is shown in FIG. This is the same as the bicycle with electric motor of the first embodiment shown.
[0059]
As shown by the solid line in FIG. 4, when the rotation speed of the electric motor is ω2, the PWM duty α2 at the peak point of the regenerative power is smaller than the value α1 when the rotation speed is ω1 (ω1 <ω2). As shown in FIG. 17, the PWM duty at the peak point of the regenerative power is increased between the rotation speed of the electric motor and the PWM duty at the peak point of the regenerative power. There is a certain relationship that decreases.
Therefore, in the bicycle with an electric motor of this embodiment, the PWM duty upper limit value table representing the relationship between the rotational speed of the electric motor and the upper limit value is provided as the upper limit value of the PWM duty at the peak point of the regenerative power. Stored in internal memory. Based on the table, the upper limit value of the PWM duty is derived from the rotational speed of the electric motor, and the PWM duty is set to a value equal to or lower than the upper limit value.
[0060]
In the bicycle with the electric motor of this embodiment, the control procedure similar to that shown in FIG. Here, since the control procedure executed by the control circuit is the same except for the PWM duty change procedure in step S9, the entire description is omitted.
[0061]
FIG. 18 shows a PWM duty change procedure executed by the control circuit of this embodiment.
First, in step S61, a motor current command value is calculated based on the output value of the rotation speed / rotation position detection circuit and the output value of the motor current detection circuit, and then in step S62, the rotation speed / rotation position detection circuit. The output value and the output value of the motor current detection circuit are acquired.
Subsequently, in step S63, it is determined whether or not the motor current value acquired in step S62 is greater than or equal to the motor current command value. If NO is determined, the process proceeds to step S64 to increase the PWM duty. Set the step width. Thereafter, a procedure for setting the PWM duty to be equal to or higher than the lower limit value corresponding to the rotational speed of the electric motor is executed. In step S66, the PWM duty is increased by the set step width, and then the process proceeds to step S68. Note that the procedures in step S64 and step S65 are the same as the procedure shown in FIG. 9 and the procedure shown in FIG.
On the other hand, if the motor current value is equal to or greater than the motor current command value and it is determined YES in step S63, the process proceeds to step S67, where the PWM duty is reduced by a predetermined step width, The process proceeds to S68.
In step S68, a later-described procedure for limiting the PWM duty to a value equal to or less than the value at the peak point of the regenerative power is executed.
[0062]
FIG. 19 shows the PWM duty limiting procedure in step S68.
First, in step S71, the upper limit value of the PWM duty is derived from the rotational speed acquired in step S62 of FIG. 18 based on the PWM duty upper limit value table stored in the built-in memory. In step S72, it is determined whether the current PWM duty is greater than or equal to the derived upper limit value. If it is determined NO, the procedure ends.
On the other hand, if the PWM duty is equal to or greater than the derived upper limit value and it is determined as YES in step S72, the process proceeds to step S73, the PWM duty is set to the upper limit value, and the procedure is terminated. .
By the above procedure, the PWM duty is set to a value equal to or less than the value at the peak point of the regenerative power.
[0063]
Fourth embodiment
The bicycle with an electric motor of this embodiment compares the motor current command value with the motor current value and changes the PWM duty only in that the PWM duty is changed by comparing the regenerative current command value with the regenerative current value. This is different from the electric motor-equipped bicycle of the third embodiment, and the PWM duty is directly suppressed to a value equal to or less than the value at the peak point of the regenerative power. The electric configuration of the bicycle with an electric motor of this embodiment is the same as that of the bicycle with an electric motor of the second embodiment shown in FIG. 11 except for the control circuit.
[0064]
In the bicycle with the electric motor of this embodiment, the control procedure similar to that shown in FIG. Here, since the control procedure executed by the control circuit is the same except for the PWM duty change procedure in step S9, the entire description is omitted.
[0065]
FIG. 20 shows a PWM duty change procedure executed by the control circuit of this embodiment. Incidentally, the same PWM duty upper limit value table as that of the third embodiment is stored in the built-in memory of the control circuit of the present embodiment.
First, in step S81, a regenerative current command value is calculated based on the output value of the rotational speed / rotational position detection circuit and the output value of the regenerative current detection circuit. The output value and the output value of the regenerative current detection circuit are acquired. Subsequently, in step S83, it is determined whether or not the regenerative current value acquired in step S82 is greater than or equal to the regenerative current command value. If NO is determined, the process proceeds to step S84 to increase the PWM duty. Set the step width. Thereafter, a procedure for setting the PWM duty to be equal to or higher than the lower limit value corresponding to the rotational speed of the electric motor is executed. In step S86, the PWM duty is increased by the set step width, and the process proceeds to step S88. The procedures in step S84 and step S85 are the same as the procedure shown in FIG. 16 and the procedure shown in FIG.
On the other hand, if the regenerative current value is greater than or equal to the regenerative current command value and it is determined YES in step S83, the process proceeds to step S87, where the PWM duty is reduced by a predetermined step width, and then step The process proceeds to S88.
In step S88, a procedure for limiting the PWM duty to a value equal to or less than the value at the peak point of the regenerative power is executed, and the above procedure is terminated. Note that the procedure of step S88 is the same as the procedure shown in FIG.
[0066]
Example 5
In the bicycles with electric motors of the third and fourth embodiments, the PWM duty is limited to a value equal to or less than the value at the peak point of the regenerative power based on the rotation speed of the electric motor. The bicycle with an electric motor limits the PWM duty to a value equal to or less than the value at the peak point of the regenerative power based on the regenerative current flowing into the battery. The electric configuration of the bicycle with an electric motor of this embodiment is the same as that of the bicycle with an electric motor of the second embodiment shown in FIG. 11 except for the control circuit.
[0067]
As shown in FIG. 21, between the magnitude of the regenerative current flowing into the battery and the PWM duty at the peak point of the regenerative power, the PWM duty at the peak point of the regenerative power decreases as the magnitude of the regenerative current increases. A certain relationship is established.
Therefore, in the bicycle with an electric motor of the present embodiment, the PWM duty upper limit value table representing the relationship between the regenerative current value and the upper limit value is set as the upper limit value of the PWM duty at the peak point of the regenerative power. Stored in Then, an upper limit value of the PWM duty is derived from the regenerative current value based on the table, and the PWM duty is set to a value equal to or lower than the upper limit value.
[0068]
In the bicycle with the electric motor of this embodiment, the control procedure similar to that shown in FIG. Here, since the control procedure executed by the control circuit is the same except for the PWM duty change procedure in step S9, the entire description is omitted.
[0069]
FIG. 22 shows a PWM duty change procedure executed by the control circuit of this embodiment.
First, in step S91, a regenerative current command value is calculated based on the output value of the rotation speed / rotational position detection circuit and the output value of the regenerative current detection circuit, and then the output value of the regenerative current detection circuit is acquired in step S92. To do.
Subsequently, in step S93, it is determined whether or not the regenerative current value acquired in step S92 is greater than or equal to the regenerative current command value. If NO is determined, the process proceeds to step S94 to increase the PWM duty. In step S95, the PWM duty is increased by the set step width, and the process proceeds to step S97. Note that the procedure of step S94 is the same as the procedure shown in FIG.
On the other hand, if the regenerative current value is greater than or equal to the regenerative current command value and it is determined YES in step S93, the process proceeds to step S96, where the PWM duty is reduced by a predetermined step width, and then the step. The process proceeds to S97.
In step S97, a procedure described later for limiting the PWM duty to a value equal to or less than the value at the peak point of the regenerative power is executed, and the above procedure is terminated.
[0070]
FIG. 23 shows the PWM duty limiting procedure in step S97.
First, in step S101, the upper limit value of the PWM duty is derived from the regenerative current value acquired in step S92 of FIG. 22 based on the PWM duty upper limit value table stored in the built-in memory. Next, in step S102, it is determined whether the current PWM duty is greater than or equal to the derived upper limit value. If it is determined NO, the procedure ends.
On the other hand, when the PWM duty is equal to or greater than the derived upper limit value and it is determined as YES in step S102, the process proceeds to step S103, the PWM duty is set to the upper limit value, and the procedure is terminated. .
By the above procedure, the PWM duty is set to a value equal to or less than the value at the peak point of the regenerative power.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the overall configuration of a bicycle with an electric motor according to the present invention.
FIG. 2 is a block diagram showing an electrical configuration of the electric motor-equipped bicycle according to the first embodiment.
FIG. 3 is a flowchart showing a control procedure executed during traveling in the electric motor-equipped bicycle according to the present invention.
FIG. 4 is a graph showing the relationship between PWM duty and regenerative power, and the relationship between PWM duty and motor current command value.
FIG. 5 is a graph showing the relationship between the rotational speed of the electric motor and the motor current command value at the peak point of regenerative power.
FIG. 6 is a graph showing the relationship between the rotational speed of the electric motor and the PWM duty at a point where the regenerative power increases rapidly.
FIG. 7 is a flowchart showing a PWM duty change procedure executed in the electric motor-equipped bicycle according to the first embodiment.
FIG. 8 is a flowchart showing a specific procedure of a motor current command value limiting procedure executed in the PWM duty changing procedure.
FIG. 9 is a flowchart showing a specific procedure of a PWM duty step width setting procedure executed in the PWM duty change procedure.
FIG. 10 is a flowchart showing a specific procedure of a PWM duty lower limit value setting procedure executed in the PWM duty change procedure.
FIG. 11 is a block diagram showing an electrical configuration of a bicycle with an electric motor according to a second embodiment.
FIG. 12 is a graph showing the relationship between PWM duty and regenerative power, and the relationship between PWM duty and regenerative current command value.
FIG. 13 is a graph showing the relationship between the rotation speed of the electric motor and the regenerative current command value at the peak point of regenerative power.
FIG. 14 is a flowchart showing a PWM duty change procedure executed in the electric motor-equipped bicycle.
FIG. 15 is a flowchart showing a specific procedure of a regenerative current command value limiting procedure executed in the PWM duty change procedure.
FIG. 16 is a flowchart showing a specific procedure of a PWM duty step width setting procedure executed in the PWM duty change procedure.
FIG. 17 is a graph showing the relationship between the rotation speed of the electric motor and the PWM duty at the peak point of regenerative power.
FIG. 18 is a flowchart showing a PWM duty change procedure executed in the electric motor-equipped bicycle according to the third embodiment.
FIG. 19 is a flowchart showing a PWM duty limit procedure executed in the PWM duty change procedure.
FIG. 20 is a flowchart showing a PWM duty change procedure executed in the electric motor-equipped bicycle according to the fourth embodiment.
FIG. 21 is a graph showing a relationship between a regenerative current value and a PWM duty at a peak point of regenerative power.
FIG. 22 is a flowchart showing a PWM duty change procedure executed in the electric motor-equipped bicycle according to the fifth embodiment.
FIG. 23 is a flowchart showing a PWM duty limit procedure executed in the PWM duty change procedure.
FIG. 24 is a schematic diagram showing the overall configuration of a conventional bicycle with an electric motor.
FIG. 25 is a block diagram showing the electrical configuration of the electric motor-equipped bicycle.
FIG. 26 is a diagram illustrating a voltage waveform of a three-phase winding of an electric motor in a regenerative travel mode and an on / off state of PWM control of switching elements S1, S3, and S5 constituting an inverter.
FIG. 27 is a circuit diagram showing a step-up chopper circuit configured by an inverter when the regenerative running mode is set.
FIG. 28 is a diagram illustrating an on / off state of switching element S1 constituting the inverter and a waveform of a current flowing through the U-phase winding.
FIG. 29 is a graph showing the relationship between PWM duty and electric power generated from an electric motor, and the relationship between PWM duty and regenerative power.
[Explanation of symbols]
(1) Bicycle body
(11) Human torque sensor
(2) Electric motor
(3) Battery
(4) Controller
(41) Control circuit
(42) Inverter
(43) Speed / rotation position detection circuit

Claims (10)

In a motor control apparatus that can control regenerative braking of an electric motor, and includes an inverter that supplies electric power generated from the electric motor to a battery that is a power source of the motor, and a PWM control circuit that controls the inverter ,
Speed detecting means for detecting the rotational speed of the electric motor ;
Motor current detection means for detecting the magnitude of the output current of the electric motor ,
The PWM control circuit is
A motor current command value representing a target value of the output current of the electric motor is calculated, and a process of changing the PWM duty based on the motor current command value and a detection result by the motor current detection means is executed. ,
The first step width (Δ1) when changing the PWM duty and the second step width (Δ2) having a smaller change width than the first step width are stored.
When the motor current value detected by the motor current detecting means is smaller than the predetermined threshold value, the PWM duty is changed by the first step width, while when the motor current value is larger than the predetermined threshold value, the PWM duty is changed. Change the duty by the second step width,
A motor control device that limits PWM duty to a value at a point at which regenerative power supplied to a battery reaches a peak or a value close to the PWM duty based on a rotational speed of an electric motor. The PWM control circuit is
Upper limit value deriving means for deriving a motor current command value at or near a point where the regenerative power supplied to the battery peaks based on the rotation speed of the electric motor as a current command upper limit value;
It is determined whether or not the calculated motor current command value exceeds the derived current command upper limit value, and when the calculated current command upper limit value is exceeded, the current command that sets the motor current command value to the upper limit value The motor control device according to claim 1, further comprising value setting means. 3. The motor control device according to claim 1, wherein the predetermined threshold is set as a motor current value corresponding to a PWM duty at a point where an output voltage of the inverter exceeds a voltage across the battery. . In a motor control apparatus that can control regenerative braking of an electric motor, and includes an inverter that supplies electric power generated from the electric motor to a battery that is a power source of the motor, and a PWM control circuit that controls the inverter ,
Regenerative current detection means for detecting the magnitude of the regenerative current flowing into the battery,
The PWM control circuit is
A regenerative current command value representing a target value of the regenerative current flowing into the battery is calculated, and a process of changing the PWM duty based on the regenerative current command value and a detection result by the regenerative current detection means is executed. ,
The first step width (Δ1) when changing the PWM duty and the second step width (Δ2) having a smaller change width than the first step width are stored.
When the regenerative current value detected by the regenerative current detection means is smaller than the predetermined threshold value, the PWM duty is changed by the first step width, while when the regenerative current value is larger than the threshold value, the PWM duty is changed. Change in the second step width,
A motor control device that limits PWM duty to a value at a point at which regenerative power supplied to a battery reaches a peak or a value close to the PWM duty based on a rotational speed of an electric motor . The PWM control circuit is
An upper limit value deriving means for deriving a regenerative current command value at a point where the regenerative power supplied to the battery reaches a peak or a value near the regenerative power based on the rotation speed of the electric motor as a current command upper limit value;
A current command that determines whether the calculated regenerative current command value exceeds the derived current command upper limit value, and sets the regenerative current command value to the upper limit value if the calculated current command upper limit value is exceeded. The motor control device according to claim 1, further comprising value setting means. 6. The motor control device according to claim 4, wherein the predetermined threshold value is set as a regenerative current value corresponding to a PWM duty at a point where the output voltage of the inverter exceeds the voltage across the battery. . The PWM control circuit is
Upper limit value deriving means for deriving the PWM duty at a point where the regenerative power supplied to the battery reaches a peak based on the rotational speed of the electric motor or a value near the PWM duty as an upper limit value of the PWM duty;
It is determined whether or not the PWM duty exceeds the derived PWM duty upper limit value, and when it exceeds the PWM duty upper limit value, a duty upper limit value setting means is provided for setting the PWM duty to the upper limit value. The motor control device according to claim 1 or 4 . The PWM control circuit is
Lower limit value deriving means for deriving a lower limit value of the PWM duty based on the rotation speed of the electric motor;
It is determined whether or not the PWM duty is lower than the derived PWM duty lower limit value, and when the PWM duty is lower than the PWM duty lower limit value, duty lower limit value setting means for setting the PWM duty to the lower limit value is provided. The motor control apparatus in any one of Claim 1 thru | or 7 . In a motor control apparatus that can control regenerative braking of an electric motor, and includes an inverter that supplies electric power generated from the electric motor to a battery that is a power source of the motor, and a PWM control circuit that controls the inverter ,
Regenerative current detection means for detecting the magnitude of the regenerative current flowing into the battery,
The PWM control circuit is
A regenerative current command value representing a target value of the regenerative current flowing into the battery is calculated, and a process of changing the PWM duty based on the regenerative current command value and a detection result by the regenerative current detection means is executed. ,
The first step width (Δ1) when changing the PWM duty and the second step width (Δ2) having a smaller change width than the first step width are stored.
When the regenerative current value detected by the regenerative current detection means is smaller than the predetermined threshold value, the PWM duty is changed by the first step width, while when the regenerative current value is larger than the threshold value, the PWM duty is changed. Change in the second step width,
A motor control device, wherein the PWM duty is limited to a value at a point where the regenerative power supplied to the battery reaches a peak or a value close to the PWM duty based on a detection result by the regenerative current detection means. The PWM control circuit is
An upper limit value deriving unit for deriving a PWM duty at a point where the power supplied to the battery reaches a peak or a value near the PWM duty based on a detection result by the regenerative current detecting unit;
It is determined whether or not the PWM duty exceeds the derived PWM duty upper limit value, and when it exceeds the PWM duty upper limit value, a duty upper limit value setting means is provided for setting the PWM duty to the upper limit value. The motor control device according to claim 9 .

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