JP5309656B2 - Motor control circuit and moving body provided with motor control circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique to control the rotational speeds of multiple motors through a relatively simple configuration. <P>SOLUTION: A control circuit 100 for a movable body equipped with multiple motors includes: multiple driving signal generation units 120L, 120R that respectively generate driving signals for respectively driving the motors; a rotation signal generation unit 32L that detects the rotational speed of one of the motors and generates a rotation signal indicating a frequency corresponding to the rotational speed; a reference rotation signal generation unit 104 that sets a target rotational speed related to one of the motors and generates a reference rotation signal indicating a frequency corresponding to the set target rotational speed; and a phase difference signal generation unit 108 that detects the phase difference between the rotation signal and the reference rotation signal and generates a phase difference signal indicating the phase difference. The driving signal generation units 120L, 120R respectively generate driving signals, based on the phase difference signal. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a control circuit for an electric motor.

  In recent years, it has been desired to improve the accuracy of control of the rotation speed of an electric motor. A brushless motor may be used as an electric motor for controlling the rotation speed. As a technique related to the brushless motor, for example, one disclosed in Patent Document 1 is known.

JP 2001-298882 A

  By the way, in recent years, vehicles using a plurality of electric motors instead of the internal combustion engine have been developed. However, there is a problem that the control of the plurality of electric motors is quite complicated and the circuit configuration is also complicated.

  An object of the present invention is to provide a technique capable of controlling the rotational speeds of a plurality of electric motors with a relatively simple configuration.

In order to solve at least a part of the problems described above, the present invention can take the following forms or application examples.
[Form]
A control circuit for a moving body including a plurality of electric motors,
A plurality of drive signal generation units that respectively generate drive signals for driving the plurality of electric motors;
And the rotational speed of the one motor of the plurality of motors is detected and that generates a rotation signal indicating the frequency corresponding to the rotational speed rotation signal generating section,
A target rotational speed set by the set that generates a reference rotation signal indicating the frequency corresponding to the target rotation speed standards rotation signal generating unit for one motor among the plurality of electric motors,
Said rotation signal and detecting a phase difference between the reference rotation signal, that generates a phase difference signal indicative of the phase difference phase difference signal generating unit,
With
The rotation signal generator is provided only for one of the plurality of electric motors,
Only one reference rotation signal generation unit is provided for the plurality of electric motors,
Only one phase difference signal generation unit is provided for the plurality of electric motors,
The plurality of drive signal generation units each generate the drive signal to the plurality of electric motors based on the phase difference signal.

[Application Example 1]
A control circuit for a moving body including a plurality of electric motors,
A plurality of drive signal generation units that respectively generate drive signals for driving the plurality of electric motors;
A rotation signal generator that detects a rotation speed of one of the plurality of electric motors and generates a rotation signal indicating a frequency according to the rotation speed;
A reference rotation signal generation unit that sets a target rotation speed for one of the plurality of electric motors, and generates a reference rotation signal indicating a frequency according to the set target rotation speed;
Detecting a phase difference between the rotation signal and the reference rotation signal and generating a phase difference signal indicating the phase difference; and
With
The plurality of drive signal generation units each generate the drive signal based on the phase difference signal.
According to the control circuit of Application Example 1, the rotation speeds of the plurality of motors can be controlled based on the target rotation speed of one of the plurality of motors.

[Application Example 2]
A control circuit according to Application Example 1,
The plurality of drive signal generation units each generate the drive signal such that the phase difference is small.
According to the control circuit of Application Example 2, the rotation speeds of the plurality of electric motors can be made to accurately follow the target rotation speed.

[Application Example 3]
The control circuit according to Application Example 1 or 2,
The plurality of drive signal generation units respectively generate the drive signals so as to cause a difference in rotational speeds of the plurality of electric motors, and perform steering angle control of the moving body.
According to the control circuit of Application Example 3, a difference occurs in the rotation speeds of the plurality of electric motors, so that the steering angle of the moving body can be controlled.

[Application Example 4]
The control circuit according to any one of Application Examples 1 to 3,
The plurality of drive signal generation units generate the drive signals so that at least one of the plurality of electric motors has a rotation direction different from the rotation direction of the other electric motors, and change the direction of the moving body. Control circuit to perform.
According to the control circuit of Application Example 4, since at least one of the rotation directions of the plurality of electric motors is different from the other rotation directions, the direction of the moving body can be easily changed. it can.

[Application Example 5]
The control circuit according to any one of Application Examples 1 to 4, further comprising:
Comprising a plurality of regenerative circuit units that cause each of the plurality of electric motors to function as a generator;
The plurality of regenerative circuit units perform steering angle control of the moving body by causing at least one of the plurality of electric motors to function as a generator so as to cause a difference in rotational speeds of the plurality of electric motors. , Control circuit.
According to the control circuit of Application Example 5, a difference occurs in the rotation speeds of the plurality of electric motors, so that the steering angle of the moving body can be controlled. Furthermore, the electric power regenerated from the regenerative circuit unit can be stored.

[Application Example 6]
A moving body having a plurality of electric motors,
The control circuit according to any one of Application Examples 1 to 5 is provided.
Moving body.

[Application Example 7]
The moving object according to Application Example 6,
A plurality of braking devices for braking rotation of the plurality of electric motors,
The plurality of braking devices perform steering angle control of the moving body by braking at least one of the plurality of electric motors so as to cause a difference in rotational speeds of the plurality of electric motors. .

  According to Application Example 6 and Application Example 7, it is possible to perform speed control and steering angle control of the moving body.

[Application Example 8]
The moving object according to Application Example 6 or 7,
The number of the plurality of electric motors is two;
A moving body in which rotation axes of two wheels rotated by the two electric motors are on a straight line.
According to Application Example 8, it is possible to perform speed control and steering angle control of a moving body in which the rotation axes of the two wheels are linear.

  Note that the present invention can be realized in various modes. For example, the present invention can be realized in the form of a control method for a moving body, a control device and a control system, an integrated circuit for realizing the functions of the method or device, a computer program, a recording medium on which the computer program is recorded, and the like.

Next, embodiments of the present invention will be described in the following order based on examples.
A. First embodiment:
B. Second embodiment:
C. Third embodiment:
D. Fourth embodiment:
E. Example 5:
F. Example 6:
G. Variations:

A. First embodiment:
FIG. 1 is an explanatory diagram showing a configuration of a moving object 1000 as an embodiment of the present invention. FIG. 1A is a view of the moving body 1000 viewed from above, and FIG. 1B is a view of the moving body 1000 viewed from the front. The moving body 1000 includes a fixed base 10, two wheels 20L and 20R, two motors 30L and 30R, two rotation sensors 32L and 32R, and a control circuit 100. The two motors 30L and 30R rotate the wheels 20L and 20R, respectively. The two rotation sensors 32L and 32R detect the rotation speeds of the motors 30L and 30R, respectively. However, as will be described later, the two rotation sensors 32L and 32R can be omitted. The control circuit 100 controls the two motors 30L and 30R. The moving body 1000 can go straight or turn by controlling the rotational speeds of the first motor 30L and the second motor 30R. Since the moving body 1000 is a two-wheeled vehicle, it is preferable to provide a gyro sensor or an inclination sensor on the fixed base 10 to balance the fixed base 10.

  FIG. 2 is a block diagram showing the configuration of the control circuit 100 of the moving body 1000 in the first embodiment. The control circuit 100 includes a CPU 102, a reference rotation signal generation unit 104, and a PLL control unit 106. The PLL control unit 106 includes a phase comparison unit 108, a loop filter 110, and a frequency divider 112. Further, the control circuit 100 includes a first PWM drive control unit 120L and a first drive driver unit 122L as circuits for controlling the first motor 30L. Similarly, the control circuit 100 includes a second PWM drive control unit 120R and a second drive driver unit 122R as circuits for controlling the second motor 30R. These operations will be described later. The first and second motors 30L and 30R are provided with first and second hall sensors 31L and 31R, respectively. The first and second hall sensors 31L and 31R output first and second magnetic pole position signals SS1 and SS2 indicating the positional relationship between the rotor and the stator in the first and second motors 30L and 30R, respectively. To do. The waveforms of the first and second magnetic pole position signals SS1, SS2 are substantially sinusoidal. In the control circuit 100, the second rotation sensor 32R is omitted. The first and second motors 30L and 30R will be described as single-phase full-wave drive motors.

  FIG. 3 is a timing chart showing signals in the control circuit 100. FIG. 3 shows a reference rotation signal BR that is an output of the reference rotation signal generation unit 104, a first sensor pulse signal CP1 that is an output of the first rotation sensor 32L, and an actual rotation speed that is an output of the frequency divider 112. The pulse signal RP, the up signal UP and down signal DW output from the phase comparison unit 108, the clock signal CLK, the LPF signal Q110 output from the loop filter 110, and the first PWM drive control unit 120L (FIG. 7). The first PWM signal PWM1 generated in (1) is drawn. Hereinafter, the operation in the control circuit 100 will be described with reference to FIGS. 2 and 3.

  The CPU 102 (FIG. 2) supplies a reference frequency command BF to the reference rotation signal generation unit 104. The reference frequency command BF determines the frequency of the reference rotation signal BR based on an external speed command. The frequency of the reference rotation signal BR indicates a target rotation speed indicated by an external speed command.

  Further, the CPU 102 supplies first and second forward / reverse rotation commands RD1 and RD2 to first and second PWM drive control units 120L and 120R, which will be described later. The first and second forward / reverse commands RD1 and RD2 are commands for determining the rotation directions of the first and second motors 30L and 30R. The reference rotation signal generation unit 104 generates a reference rotation signal BR based on the reference frequency command BF. As described above, the reference rotation signal BR is a signal indicating the rotation speed of the control target of the first and second motors 30L and 30R.

  The first rotation sensor 32L outputs a first sensor pulse signal CP1 indicating a frequency corresponding to the rotation speed of the first motor 30L. For example, a rotary encoder or the like can be used as the first rotation sensor 32L. The frequency divider 112 divides the first sensor pulse signal CP1 to output an actual rotational speed pulse signal RP corresponding to the rotational speed of the first motor 30L. In the first sensor pulse signal CP1 in the present embodiment, six pulses are generated when the motor makes one revolution. The actual rotational speed pulse signal RP generates one pulse while the first sensor pulse signal CP1 generates six pulses. That is, the actual rotational speed pulse signal RP generates one pulse when the motor makes one revolution. However, the number of pulses generated by each signal during one rotation of the motor can be set to an arbitrary number.

  The phase comparison unit 108 compares the phase of the reference rotation signal BR with the phase of the actual rotation speed pulse signal RP, and outputs a phase difference signal PD indicating the phase difference. In this embodiment, the rotational speeds of the two motors 30L and 30R are controlled based on the phase difference signal PD. The phase difference signal PD includes an up signal UP and a down signal DW. That is, when the reference rotation signal BR rises prior to the actual rotation speed pulse signal RP, the phase comparison unit 108 increases the phase of the actual rotation speed pulse signal RP, and therefore increases at the rising edge of the reference rotation signal BR. The signal UP is set to high level, and then the up signal UP is set to low level at the rising edge of the actual rotational speed pulse signal RP. Further, when the actual rotational speed pulse signal RP rises prior to the reference rotational signal BR, the phase comparison unit 108 delays the phase of the actual rotational speed pulse signal RP, and therefore the rising edge of the actual rotational speed pulse signal RP. The down signal DW is set to the high level at, and then the down signal DW is set to the low level at the rising edge of the reference rotation signal BR. The loop filter 110 outputs an LPF signal Q110 based on the up signal UP and the down signal DW of the phase difference signal PD. The operation of the loop filter 110 will be described later.

  As will be described later, the first PWM drive control unit 120L generates the first PWM signal PWM1 based on the LPF signal Q110, and further, the first PWM signal PWM1 and a first forward / reverse rotation command RD1 supplied from the CPU 102, A first drive signal DRV1 is generated based on the first magnetic pole position signal SS1 supplied from the first Hall sensor 31L. The duty ratio of the first PWM signal PWM1 is calculated based on the LPF signal Q110. The first drive driver unit 122L drives the first motor 30L based on the first drive signal DRV1. The operations of the second PWM drive control unit 120R and the second drive driver unit 122R are the same as those of the first PWM drive control unit 120L and the first drive driver unit 122L, respectively, and thus description thereof is omitted.

  FIG. 4 is an explanatory diagram showing an internal configuration of the reference rotation signal generation unit 104. The reference rotation signal generation unit 104 includes a crystal oscillator 130, a frequency divider 131, a phase comparison unit 132, a loop filter 134, a voltage oscillator (VCO) 136, and a frequency divider 138. Here, the phase comparison unit 132, the loop filter 134, the voltage oscillator 136, and the frequency divider 138 constitute a PLL circuit 140. The CPU 102 can rewrite the value of the frequency division value M of the frequency divider 131 and the value of the frequency division value N of the frequency divider 138 by the reference frequency command BF, and the reference rotation output from the voltage oscillator 136. The frequency of the signal BR can be arbitrarily set.

  5A is an explanatory diagram showing a configuration of the loop filter 110, and FIG. 5B is a timing chart showing signals input to and output from the loop filter 110. FIG. The loop filter 110 is an up / down counter, and receives the up signal UP and the down signal DW output from the phase comparison unit 108 and the clock signal CLK, and outputs the LPF signal Q110. That is, the loop filter 110 adds the output value of the LPF signal Q110 in synchronization with the clock signal CLK during the period in which the up signal UP indicates a high level, and during the period in which the down signal DW indicates a high level. The output value of the LPF signal Q110 is subtracted in synchronization with the clock signal CLK.

  FIG. 6 is an explanatory diagram showing an example of the loop filter 110 realized by an analog circuit. The loop filter 110 shown in FIG. 6 is a lag type low-pass filter. Even if the loop filter 110 is configured by such an analog circuit, the phase difference signal PD that is the output from the phase comparator 108 can be smoothed. The loop filter 110 converts the analog signal output into a digital signal and then outputs the LPF signal Q110.

  FIG. 7 is an explanatory diagram illustrating an example of an internal configuration of the first PWM drive control unit 120L. The first PWM drive control unit 120L includes a PWM signal generation unit 152 and a multiplexer 154. The PWM signal generation unit 152 generates the first PWM signal PWM1 according to the signal level of the LPF signal Q110. The multiplexer 154 generates the first drive signal DRV1 based on the first PWM signal PWM1, the forward / reverse rotation command RD from the CPU 102, and the first magnetic pole position signal SS1 from the first Hall sensor 31L. The first drive signal DRV1 is supplied to the first drive driver unit 122L (FIG. 2).

  FIG. 8A is an explanatory diagram illustrating an example of a method for generating the first PWM signal PWM1 in the PWM signal generation unit 152. FIG. 8B is a graph showing the relationship between the output level of the LPF signal Q110 and the duty ratio of the first PWM signal PWM1. The comparator 156 provided in the PWM signal generation unit 152 compares the LPF signal Q110 with the reference triangular wave TW, and outputs the comparison result as the first PWM signal PWM1 (FIG. 8A). That is, if the output level of the LPF signal Q110 is large, the duty ratio of the first PWM signal PWM1 generated by the PWM signal generation unit 152 is large (FIG. 8B), and the rotation speed of the first motor 30L is large. On the other hand, if the output level of the LPF signal Q110 is small, the duty ratio of the first PWM signal PWM1 generated by the PWM signal generation unit 152 is small, and the rotation speed of the first motor 30L is small. Here, since the LPF signal Q110 having the same output level is supplied to the first PWM drive control unit 120L and the second PWM drive control unit 120R (FIG. 2), the rotational speeds of the first and second motors 30L and 30R. Can be made equal.

  FIG. 9 is a timing chart showing signals in the multiplexer 154. FIG. 9 shows a case where the output level of the LPF signal Q110 is constant, and the duty ratio of the first PWM signal PWM1 is drawn constant. FIG. 9 shows signals when the first forward / reverse rotation command RD1 instructs forward rotation.

  The multiplexer 154 outputs two first drive signals DRV1a and DRV1b based on the first PWM signal PWM1 and the first magnetic pole position signal SS1. That is, the multiplexer 154 outputs the first PWM signal PWM1 as the first drive signal DRV1a in the section where the signal level of the first magnetic pole position signal SS1 is larger than the predetermined threshold Th, while the signal of the first magnetic pole position signal SS1. In a section where the level is smaller than the predetermined threshold Th, the first PWM signal PWM1 is output as the first drive signal DRV1b. When the first forward / reverse rotation command RD1 instructs reverse rotation, the first and second PWM signals PWM1 and PWM2 are switched and output. The threshold Th is preferably the middle point of the maximum value indicated by the first magnetic pole position signal SS1.

  FIG. 10 is a circuit diagram illustrating an example of an internal configuration of the first drive driver unit 122L. The first drive driver unit 122L is an H-type bridge circuit including four diodes D1 to D4 and four transistors TR1 to TR4. The first drive signal DRV1a is supplied to the transistors TR1 and TR4, while the first drive signal DRV1b is supplied to the transistors TR2 and TR3. As shown in FIG. 9, the two first drive signals DRV1a and DRV1b alternately show a high level every half cycle of the first magnetic pole position signal SS1. Thereby, the direction of the current flowing through the electromagnetic coil 38 in the first motor 30L is alternately switched between the i1 direction and the i2 direction. Therefore, since the direction of the magnetic field generated by the electromagnetic coil 38 is switched every half cycle of the first magnetic pole position signal SS1, the first motor 30L can rotate. The four diodes D1 to D4 are provided to protect the transistors TR1 to TR4 from a surge voltage that is generated when the four transistors TR1 to TR4 are switched ON / OFF.

  According to the mobile body configured as described above, the rotational speeds of the first and second motors 30L and 30R can be controlled to the target rotational speed by only providing one PLL control unit 106 in the control circuit 100. It becomes possible. Furthermore, if one of the first and second motors 30L, 30R is temporarily stopped by a short brake, the direction of the moving body can be changed. Here, “short brake” means that the signal level input to the transistors TR1 and TR3 in FIG. 10 is set to VCC, and the signal level input to the transistors TR2 and TR4 is decreased to GND, for example. This is a method of stopping rotation. The direction of the moving body can also be changed by rotating one of the first and second motors 30L and 30R in the normal direction and rotating the other in the reverse direction.

  The PWM drive control units 120L and 120R correspond to the drive signal generation unit in the present invention, and the rotation sensors 32L and 32R correspond to the rotation signal generation unit in the present invention. The phase comparison unit 108 corresponds to the phase difference signal generation unit in the present invention.

B. Second embodiment:
FIG. 11 is a block diagram showing the configuration of the moving body control circuit 100b in the second embodiment. The only difference from the first embodiment shown in FIG. 2 is that the first and second mechanical brakes 34L and 34R are provided in the first and second motors 30L and 30R, respectively. The configuration is the same as that of the first embodiment. The CPU 102 in the control circuit 100b supplies first and second brake commands BC1 and BC2 to the two mechanical brakes 34L and 34R, respectively. The first and second mechanical brakes 34L and 34R adjust the braking force in accordance with the respective brake commands BC1 and BC2. Here, the CPU 102 can generate the two brake commands BC1 and BC2 so that the braking forces of the two mechanical brakes 34L and 34R are different. In this way, even if the driving forces of the two motors 30L and 30R are the same, it is possible to make a difference in the rotational speeds of the two motors 34L and 34R. Therefore, according to the moving body of the second embodiment, it is possible to make a difference in the rotational speeds of the wheels 20L and 20R, and to realize the steering angle control of the moving body.

  FIG. 12 is an explanatory diagram showing the configuration of the first mechanical brake 34L. The configuration of the second mechanical brake 34R is the same as that of the first mechanical brake 34L shown in FIG. The first mechanical brake 34L includes an exciting coil 60, a spring 62, a movable iron core 64, and a brake lining 66. The first mechanical brake 34L is a non-excitation operation type brake. That is, when the exciting coil 60 is in a non-energized state, the movable iron core 64 is pressed against the brake lining 66 by the force of the spring 62, and a braking force is generated for the first motor 30L. On the other hand, when the exciting coil 60 is energized, the movable iron core 64 is attracted to the exciting coil 60, so that a gap is formed between the movable iron core 64 and the brake lining 66. Therefore, when the exciting coil 60 is in an energized state, no braking force is generated on the first motor 30L.

  The mechanical brakes 34L and 34R correspond to the “braking device” in the present invention.

C. Third embodiment:
FIG. 13 is a block diagram showing the configuration of the moving body control circuit 100c in the third embodiment. The only difference from the second embodiment shown in FIG. 11 is that a regenerative brake system 172L, 172R is provided instead of the mechanical brakes 34L, 34R, and a power storage unit 174 is provided, Other configurations are the same as those of the second embodiment. Regenerative brake systems 172L and 172R adjust the respective brake forces according to regenerative brake commands RBC1 and RBC2, respectively. Therefore, the two regenerative braking systems 172L and 172R can also make a difference in the rotational speeds of the wheels 20L and 20R of the moving body and realize the steering angle control of the moving body. Furthermore, in regenerative braking systems 172L and 172R, it is possible to charge power storage unit 174 during braking.

  The regenerative braking systems 172L and 172R correspond to the “regenerative circuit unit” in the present invention.

D. Fourth embodiment:
FIG. 14 is a block diagram showing a configuration of a moving body control circuit 100d in the fourth embodiment. The only difference from the first embodiment shown in FIG. 2 is that the first and second amplitude adjustment units 176L and 176R are provided in front of the two PWM drive control units 120L and 120R, respectively. Other configurations are the same as those of the first embodiment. The first amplitude adjustment unit 176L adjusts the level of the LPF signal Q110, which is the output of the loop filter 110, in accordance with the first amplitude adjustment command AS1 from the CPU 102, and supplies the adjusted signal to the first PWM drive control unit 120L. Similarly, the second amplitude adjustment unit 176R adjusts the level of the LPF signal Q110, which is the output of the loop filter 110, in accordance with the second amplitude adjustment command AS2 from the CPU 102, and sends the adjusted signal to the second PWM drive control unit 120R. Supply.

  Here, if the first amplitude adjustment command AS1 is different from the first amplitude adjustment command AS2, the level of the LPF signal Q110 supplied to the first PWM drive control unit 120L and the LPF supplied to the second PWM drive control unit 120R. The level of the signal Q110 is different, and a difference occurs between the rotation speed of the first motor 30L and the rotation speed of the second motor 30R. Therefore, the two amplitude adjusting units 176L and 176R can also make a difference in the rotational speeds of the wheels 20L and 20R of the moving body, thereby realizing the steering angle control of the moving body.

  The amplitude adjustment units 176L and 176R and the PWM drive control units 120L and 120R correspond to the “drive signal generation unit” in the present invention.

E. Example 5:
FIG. 15 is a block diagram showing the configuration of the moving body control circuit 100e in the fifth embodiment. The difference from the first embodiment shown in FIG. 2 is that the internal configurations of the first and second PWM drive control units 120Le and 120Re are different, and the first and second PWM drive control units 120Le and 120Re. On the other hand, the first and second excitation ratio commands EC1 and EC2 are supplied.

  FIG. 16 is a block diagram showing an internal configuration of the first PWM drive control unit 120Le in the fifth embodiment. The first PWM drive control unit 120Le includes a PWM signal generation unit 152, a multiplexer 154e, and an excitation interval setting unit 155. The operation of the PWM signal generator 152 is the same as that of the PWM signal generator 152 (FIGS. 7 and 8) in the first embodiment. The excitation interval setting unit 155 generates the first excitation signal ENB1 based on the first excitation ratio command EC1 supplied from the CPU 102 and the first magnetic pole position signal SS1. As will be described later, the first excitation signal ENB1 defines a period during which the first PWM signal PWM1 is valid (hereinafter also referred to as an excitation interval EP) and a period during which the first PWM signal PWM1 is invalid (hereinafter also referred to as a non-excitation interval NEP). Signal. The multiplexer 154e generates two drive signals DRV1a and DRV1b based on the first PWM signal PWM1, the first magnetic pole position signal SS1, and the first excitation signal ENB1.

  FIG. 17 is an explanatory diagram showing the internal configuration and operation of the excitation interval setting unit 155. The excitation interval setting unit 155 includes an electronic variable resistor 592, voltage comparators 594, 596, and an OR circuit 598. The resistance value Rv of the electronic variable resistor 592 is set by a first excitation ratio command EC1 supplied from the CPU 102. Voltages V1 and V2 across the electronic variable resistor 592 are applied to one input terminal of a voltage comparator 594,596. The first magnetic pole position signal SS1 is supplied to the other input terminal of the voltage comparators 594,596. Output signals Sp and Sn of the voltage comparators 594 and 596 are input to the OR circuit 598. As described above, the output of the OR circuit 598 is the first excitation signal ENB1 for distinguishing between the excitation interval EP and the non-excitation interval NEP.

  FIG. 17B shows the operation of the excitation interval setting unit 155. Both-end voltages V1 and V2 of the electronic variable resistor 592 are changed by adjusting the resistance value Rv. Specifically, both-end voltages V1 and V2 are set to values having the same difference from the median value (= VDD / 2) of the voltage range. When the first magnetic pole position signal SS1 is higher than the first voltage V1, the output Sp of the first voltage comparator 594 becomes H level, while the first magnetic pole position signal SS1 is lower than the second voltage V2. In this case, the output Sn of the second voltage comparator 596 becomes H level. The first excitation signal ENB1 is a signal obtained by taking the logical sum of these output signals Sp and Sn. Therefore, as shown in the lower part of FIG. 17B, the first excitation signal ENB1 can be used as a signal indicating the excitation interval EP and the non-excitation interval NEP. The excitation interval EP and the non-excitation interval NEP are set by adjusting the variable resistance value Rv according to the first excitation ratio command EC1 supplied from the CPU 102.

  FIG. 18 is an explanatory diagram showing the relationship between the first excitation ratio command EC1 and the first excitation signal ENB1. The ratio between the excitation interval EP and the non-excitation interval NEP indicated by the first excitation signal ENB1 (hereinafter also referred to as the excitation rate) is set according to the level of the first excitation ratio command EC1. FIG. 18A shows an example of the first excitation signal ENB1 when the excitation rate is 20%, 50%, and 100%. Further, the relationship between the signal level of the first excitation ratio command EC1 and the excitation rate can be set to a proportional relationship as shown in FIG.

  FIG. 19 is a timing chart showing signals in the multiplexer 154e. The two drive signals DRV1a and DRV1b generate pulses of the first PWM signal PWM1 only in the excitation interval EP in which the first excitation signal ENB1 indicates a high level. That is, the multiplexer 154e masks the first PWM signal PWM1 by the non-excitation interval NEP. Therefore, if the excitation rate is set to be small by the first excitation ratio command EC1, the masked area of the first PWM signal PWM1 becomes large, so that the rotation speed of the first motor 30L can be reduced. On the other hand, if the excitation rate is set to be large by the first excitation ratio command EC1, the masked area of the first PWM signal PWM1 becomes small, so that the rotation speed of the first motor 30L can be increased.

  According to the control circuit 100e having the above configuration, if the first excitation ratio command EC1 and the second excitation ratio command EC2 are set differently by the CPU 102, the first and second motors 30L and 30R have different rotational speeds. It becomes possible. Therefore, this control circuit 100e can also make a difference in the rotational speeds of the wheels 20L and 20R of the moving body to realize the steering angle control of the moving body.

  The PWM drive control units 120Le and 120Re correspond to the “drive signal generation unit” in the present invention.

F. Example 6:
FIG. 20 is a block diagram showing the configuration of the moving body control circuit 100f in the sixth embodiment. The difference from the first embodiment shown in FIG. 2 is that two reference rotation signal generation units 104 and two PLL control units 106 are provided. According to the control circuit 100f, the first and second motors 30L and 30R can be controlled independently. That is, if the CPU 102 sets the first reference frequency command BF1 and the second reference frequency command BF2 to be different, the first and second motors 30L and 30R can be set to different rotational speeds. Therefore, the control circuit 100f can also make a difference in the rotational speed of the wheels of the moving body and realize the steering angle control of the moving body.

G. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

G1. Modification 1:
In the above embodiment, the first sensor pulse signal CP1 which is the output of the first rotation sensor 32L is used as the signal indicating the rotation speed of the motor. Instead, the first sensor which is the output of the first hall sensor 31L. It is also possible to use a signal obtained by converting the output of the magnetic pole position signal SS1 into a rectangular wave by a comparator. In this case, the first rotation sensor 32L can be omitted.

G2. Modification 2:
In the above embodiment, the first and second PWM drive control units 120L and 120R are based on the first and second magnetic pole position signals SS1 and SS2 that are the outputs of the first and second Hall sensors 31L and 31R, respectively. Thus, the first and second drive signals DRV1 are generated. Instead, two rotation sensors are provided, and the first and second sensor pulse signals CP1, which are outputs of the two rotation sensors, are provided. The first and second drive signals DRV1 may be generated based on CP2.

It is explanatory drawing which shows the structure of the moving body as one Example of this invention. It is a block diagram which shows the structure of the control circuit of the moving body in 1st Example. It is a timing chart which shows the signal in a control circuit. It is explanatory drawing which shows the internal structure of a reference | standard rotation signal production | generation part. It is explanatory drawing which shows the structure of a loop filter, and a timing chart which shows the signal input / output with respect to a loop filter. It is explanatory drawing which shows an example of the loop filter implement | achieved by the analog circuit. It is explanatory drawing which shows an example of an internal structure of a 1st PWM drive control part. It is explanatory drawing which shows an example of the production | generation method of the 1st PWM signal in a PWM signal production | generation part, and the graph which shows the relationship between the output level of a LPF signal, and the duty ratio of a 1st PWM signal. It is a timing chart which shows the signal in a multiplexer. It is a circuit diagram which shows an example of an internal structure of a 1st drive driver part. It is a block diagram which shows the structure of the control circuit of the moving body in 2nd Example. It is explanatory drawing which shows the structure of a 1st mechanical brake. It is a block diagram which shows the structure of the control circuit of the moving body in 3rd Example. It is a block diagram which shows the structure of the control circuit of the moving body in 4th Example. It is a block diagram which shows the structure of the control circuit of the moving body in 5th Example. It is a block diagram which shows the internal structure of the 1st PWM drive control part in 5th Example. It is explanatory drawing which shows the internal structure and operation | movement of an excitation area setting part. It is explanatory drawing which shows the relationship between a 1st excitation ratio command and a 1st excitation signal. It is a timing chart which shows the signal in a multiplexer. It is a block diagram which shows the structure of the control circuit of the moving body in 6th Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fixed stand 20L ... Wheel 20R ... Wheel 30L ... 1st motor 30R ... 2nd motor 31L ... 1st hall sensor 31R ... 2nd hall sensor 32L ... 1st rotation sensor 32R ... 2nd rotation sensor 34L ... 1st mechanical brake 34R ... second mechanical brake 38 ... electromagnetic coil 60 ... excitation coil 62 ... spring 64 ... movable iron core 66 ... brake lining 100 ... control circuit 100b ... control circuit 100c ... control circuit 100d ... control circuit 100e ... control circuit 100f ... control circuit 102 ... CPU
DESCRIPTION OF SYMBOLS 104 ... Reference rotation signal production | generation part 106 ... PLL control part 108 ... Phase comparison part 110 ... Loop filter 112 ... Divider 122L ... 1st drive driver part 122R ... 2nd drive driver part 130 ... Crystal oscillator 131 ... Divider 132 ... Phase comparison unit 134 ... Loop filter 136 ... Voltage oscillator 138 ... Divisor 140 ... PLL circuit 152 ... PWM signal generation unit 154 ... Multiplexer 154e ... Multiplexer 155 ... Excitation section setting unit 156 ... Comparator 172L ... First regenerative braking system 172R 2nd regenerative braking system 174 Power storage unit 176L 1st amplitude adjustment unit 176R 2nd amplitude adjustment unit 592 Electronic variable resistor 594 Voltage comparator 594 1st voltage comparator 596 2nd voltage comparison 1000 ... Moving object

Claims (8)

A control circuit for a moving body including a plurality of electric motors,
A plurality of drive signal generation units that respectively generate drive signals for driving the plurality of electric motors;
And the rotational speed of the one motor of the plurality of motors is detected and that generates a rotation signal indicating the frequency corresponding to the rotational speed rotation signal generating section,
A target rotational speed set by the set that generates a reference rotation signal indicating the frequency corresponding to the target rotation speed standards rotation signal generating unit for one motor among the plurality of electric motors,
Said rotation signal and detecting a phase difference between the reference rotation signal, that generates a phase difference signal indicative of the phase difference phase difference signal generating unit,
With
The rotation signal generator is provided only for one of the plurality of electric motors,
Only one reference rotation signal generation unit is provided for the plurality of electric motors,
Only one phase difference signal generation unit is provided for the plurality of electric motors,
The plurality of drive signal generation units each generate the drive signal to the plurality of electric motors based on the phase difference signal. The control circuit according to claim 1,
The plurality of drive signal generation units each generate the drive signal such that the phase difference is small. The control circuit according to claim 1 or 2,
The plurality of drive signal generation units respectively generate the drive signals so as to cause a difference in rotational speeds of the plurality of electric motors, and perform steering angle control of the moving body. A control circuit according to any one of claims 1 to 3,
The plurality of drive signal generation units generate the drive signals so that at least one of the plurality of electric motors has a rotation direction different from the rotation direction of the other electric motors, and change the direction of the moving body. Control circuit to perform. The control circuit according to any one of claims 1 to 4, further comprising:
Comprising a plurality of regenerative circuit units that cause each of the plurality of electric motors to function as a generator;
The plurality of regenerative circuit units perform steering angle control of the moving body by causing at least one of the plurality of electric motors to function as a generator so as to cause a difference in rotational speeds of the plurality of electric motors. , Control circuit. A moving body having a plurality of electric motors,
The control circuit according to claim 1 is provided.
Moving body. The mobile body according to claim 6, further comprising:
A plurality of braking devices for braking rotation of the plurality of electric motors,
The plurality of braking devices perform steering angle control of the moving body by braking at least one of the plurality of electric motors so as to cause a difference in rotational speeds of the plurality of electric motors. . The moving body according to claim 6 or 7,
The number of the plurality of electric motors is two;
A moving body in which rotation axes of two wheels rotated by the two electric motors are on a straight line.

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