JPH0898583A - Method and apparatus for controlling brushless motor - Google Patents

Abstract

PURPOSE: To enable the optimum energization switching of armature windings, and to reduce the cost. CONSTITUTION: Concerning a method and an apparatus for controlling three- phase brushless motor by detecting the position of the rotor 1a of the brushless motor 1, and switching the energization of the three armature windings on the basis of the timing of this position detection, the terminal voltage (induced voltage) R of one armature winding is divided by a voltage divider circuit 10a, and this divided voltage is compared with a fixed reference voltage from a reference voltage generating circuit 10b by a comparator circuit 10c, to obtain a positional signal Ro at the timing of the intersection of this comparison result, and this positional signal Ro is inputted to a control circuit (microcomputer) 11. This control circuit 11 obtains a timing signal (optimum energization switching time) delayed by a specified phase angle from the edge of the positional signal R0, and turns on and off a plurality of switching elements of an inverter section 2 after the passage of this time to switch the energization the armature windings.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation control technique for a brushless motor used for a motor of an air conditioner, and more particularly, to a brushless motor for surely detecting an accurate rotor position to control the rotation of the brushless motor. The present invention relates to a motor control method and an apparatus thereof.

[0002]

2. Description of the Related Art In controlling the rotation of a DC brushless motor (hereinafter referred to as a three-phase brushless motor),
Conventionally, for example, the control device shown in FIG. 7 is used.

That is, this control device switches a plurality of switching elements (in order to switch the power supply Vcc obtained by converting an AC power supply into a direct current by an AC / DC converter and apply it to the armature winding of the brushless motor 1). Inverter unit 2 with bridge connection of transistors) and brushless motor 1
The position detection unit 3 that detects the position of the rotor 1a based on the terminal voltages (for example, voltages having a phase difference of 120 degrees; induced voltage) R, S, and T, and energization of each armature winding of the brushless motor 1 are predetermined. And outputs a signal for driving the inverter unit 2 in order to switch the energization of each armature winding based on the position detection signals A, B and C from the position detection unit 3 in a predetermined manner. A control circuit (microcomputer) 4 that outputs a chopping signal that chops a predetermined signal among the signals at a predetermined ON / OFF ratio, and a chopping unit 5 that combines and outputs the drive signal and the chopping.
And the switching elements U, V, W, X of the inverter unit 2 by the drive signal including the chopped signal.
And a driver unit 6 for driving Y and Z.

In this control device, when the brushless motor 1 is started, the brushless motor 1 is synchronously operated for a predetermined time, but after the elapse of the predetermined time, the brushless motor 1 is detected based on the position detection signal of the rotor 1a of the brushless motor 1. Rotation control (switch to operation by so-called position detection).

In the operation by the position detection, the position of the rotor 1a is detected, and the energization of each armature winding is switched based on this position detection. The switching timing is induced by each armature winding. Generally, the phase angle is delayed by 30 degrees or 90 degrees from the neutral point of the voltage.

Therefore, the position detecting section 3 divides the terminal voltages R, S and T of the armature windings shown in FIGS. 8A, 8B and 8C by the voltage dividing circuit 3a, These divided voltages are smoothed by the differentiating circuit 3b and the integrating circuit 3c,
And the phase angle is delayed by 90 degrees ((d), (e) in the figure,
(Shown in (f)). Further, the signals (voltages) delayed by the phase angle of 90 degrees are compared with a predetermined reference voltage (neutral point voltage) by the comparison circuit 3d by each comparator, and the position detection signals A, B,
C is obtained (shown in (g), (h), and (i) of the same figure). The reference voltage is the output of the integration circuit 3c and the resistance circuit 3e.
It was obtained by synthesizing in. Also, as shown in FIG.
In (b) and (c), D is a spike voltage generated at the time of switching energization.

The position detection signals A, B and C are transmitted to the control circuit 4
The control circuit 4 detects the position of the rotor 1a and switches the energization of each armature winding based on the timing of each position detection.
It outputs a signal for turning on and off each switching element. This signal is the upper arm signal and the lower arm signal shown in FIGS. 8 (j) to 8 (o), and the upper arm signal is the transistor U, V, W constituting the upper arm of the inverter unit 2.
Is driven on and off, and the lower arm signal drives the transistors X, Y and Z forming the lower arm of the inverter unit 2 on and off.

Further, the control circuit 4 outputs a chopping signal to the chopping unit 5, and the chopping unit 5 chops the L level of one arm signal, for example (FIG. 8).
(Q), (r), (s) shown).

As described above, the energization of each armature winding of the brushless motor 1 is switched based on the position detection signals A, B and C to control the rotation of the brushless motor 1 and the on / off ratio () of the chopping signal ( The brushless motor 1 is controlled to a predetermined rotation speed by varying the on time and the off time.

[0010]

SUMMARY OF THE INVENTION In the above brushless motor control method, each terminal voltage (induced voltage) R,
The position detection unit 3 detects the chopping waveform included in S and T.
The position detection signal of the rotor 1a is obtained by integrating the voltage from which the chopping waveform has been removed, and the position detection signal of the rotor 1a is smooth, so that the position of the rotor 1a can be easily detected. Becomes

However, the terminal voltages R, S, T of the armature windings are not limited to the frequency components of the chopping signal, but various frequency components such as the frequency component of the rotational speed and the frequency component of the waveform of the induced voltage (sine wave component). ) Etc. are included. Therefore, when the terminal voltages R, S, and T are passed through the integral filter of the position detector 3 to obtain the position detection signals A, B, and C, the characteristics of the integral filter cause a change in the rotation speed of the brushless motor 1. The output of the position detector 3 does not delay the phase angle by 90 degrees with respect to the neutral point potential of the induced voltage, that is, an error occurs in the phase difference of the 90 degree delay.

Further, when it is necessary to control the brush motor 1 in a wide range of rotation speeds, the phase angle 90 degree delay greatly differs depending on each rotation speed, that is, the phase angle 90 degree error becomes large. There is a problem that not only an error occurs in the position detection of the rotor 1a, but also the error becomes large, and the operating efficiency of the brushless motor 1 becomes worse.

Further, since the integrating circuits for three phases are used, there is a problem that the number of parts is increased and the cost is increased.

Furthermore, the phase difference when the operating efficiency is maximized during one cycle (one rotation) of the brushless motor differs depending on the number of rotations and the load condition, and the above-mentioned method (the phase angle of 90 degrees is used as the position detection timing). If the energization of the armature winding is switched at the position detection timing according to the method), there is a problem that the operation efficiency is not good.

The present invention has been made in view of the above problems, and an object thereof is to obtain an appropriate rotor position detection timing without using an integrating circuit or the like, and to enable optimum energization switching. It is another object of the present invention to provide a brushless motor control method and apparatus that can maximize operating efficiency and reduce costs.

[0016]

In order to achieve the above object, the present invention relates to a rotor of a brushless motor when a DC power source is switched by inverter means and applied to an armature winding of a three-phase brushless motor. Is a control method of a brushless motor that drives the inverter means based on the position detection of the armature winding to switch the energization of the armature winding, wherein one terminal voltage of the terminal voltage (induced voltage) of the armature winding is While comparing with a predetermined reference voltage and calculating a time corresponding to a predetermined phase angle delay from the intersection as the comparison result, the next energization switching timing of the armature winding is obtained based on the calculated time, and the energization is performed. The gist is that the signal for driving the inverter means is generated in accordance with the switching timing.

Further, in order to obtain the timing of the above-mentioned intersection, one terminal voltage of the terminal voltage (induced voltage) of the armature winding is inputted to the position detecting means, and the position detecting means predetermines the input terminal voltage. The voltage is divided, and the divided voltage is compared with a predetermined reference voltage to obtain the timing of the intersection. Then, the position signal of the comparison result is input to the control means, and the control means obtains the next energization switching timing time of the armature winding by the input position signal, while the timing of the intersection and the obtained timing time. Generates a signal for driving the inverter means for switching the next energization of the armature winding.

[0018]

According to the above means, the terminal voltage of one armature winding is divided by the voltage dividing circuit, the divided voltage is compared with the predetermined reference voltage by the comparison circuit, and the intersection point of the comparison results is obtained. A position signal with the timing is input to the control circuit (microcomputer).

This control circuit calculates the time corresponding to the predetermined phase angle delay (phase difference) from the edge of the input position signal, for example, the time corresponding to the phase angles of 30 degrees, 90 degrees and 150 degrees. These calculated times are added to the edge detection times, and at the time when these added times have elapsed, a signal for driving the inverter means for switching the energization of the armature winding is output.

Further, since the phase difference differs depending on, for example, the number of revolutions and the load state, the time corresponding to the phase difference other than 30 degrees, 90 degrees and 150 degrees (the time corresponding to the phase difference that maximizes the operation efficiency). ) Is set, that is, the time corresponding to the phase difference that enables optimum operation is calculated.

The time calculated in this way is added to the edge detection time, and a signal for driving the inverter means for switching the energization of the armature winding is output when the added time elapses.

Further, in order to obtain the position signal, a voltage divider circuit and a comparator circuit for one phase and a reference voltage generating circuit for generating a reference voltage may be provided, and it is not necessary to provide an integrating circuit or the like. Moreover, a circuit for three phases is not required.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A brushless motor control method and apparatus according to the present invention detect the position of a rotor of a three-phase DC brushless motor (hereinafter referred to as a brushless motor), and a plurality of armatures are detected based on the position detection timing. When switching the energization of the winding, the time of the predetermined phase difference is predicted based on the timing of the intersection obtained by comparing the terminal voltage (induced voltage) of one armature winding with the predetermined reference voltage. Focusing on the fact that it is possible, the optimum energization switching time is predicted based on the timing of the intersection, and when the predicted time elapses, the energization of the armature winding is switched to control the rotation of the brushless motor.

Therefore, the controller of the brushless motor of the present invention has, for example, the configuration shown in FIG. In addition,
7, those parts which are the same as those corresponding parts in FIG. 7 described above are designated by the same reference numerals, and a description thereof will be omitted.

In FIG. 1, this control device is arranged so that one of the terminal voltages (induced voltages) R, S, T, for example, the induced voltage of the terminal voltage R, is applied to the three armature windings of the three-phase brushless motor 1. The position detector 10 that detects the neutral point and outputs the position signal R0 as the timing of the neutral point, and the time between the edges of the position signal R0 is measured, and a predetermined phase is calculated based on the measured time. Angular delay (eg phase difference 30
Degrees, 90 degrees and 150 degrees),
From the edge of the position signal, calculate the elapsed time point by the rotor 1a.
A control circuit (microcomputer) 11 for switching the energization of the three armature windings of the brushless motor 1 is provided as the position detection timing.

The position detecting section 10 divides the input terminal voltage R by a voltage dividing circuit 10a, a reference voltage generating circuit 10b for generating a predetermined reference voltage (Vcc / 2), and the divided voltage and the reference voltage. And a comparison circuit 10c for comparing the above-mentioned results, and outputs a position signal R0 as the neutral point timing of the induced voltage resulting from this comparison result. The voltage division ratio in the voltage dividing circuit 10a and the resistance ratio in the reference voltage generating circuit 10b are set so that the neutral point of the induced voltage can be detected.

In addition to the function of the control circuit 4 shown in FIG. 9, the control circuit 11 turns on / off the upper arm transistors U, V, W and the lower arm transistors X, Y, Z of the inverter section 2. It has a function of outputting a control signal for switching the chopping of the signal to the chopping unit 5.

Further, in calculating the time corresponding to the above-mentioned predetermined phase angle delay, the optimum phase difference with respect to the rotational speed and the load condition, that is, the time corresponding to the phase difference at which the operating efficiency of the brushless motor 1 is maximized is set. It is preferable to calculate.

Next, the operation of the control device will be described in detail with reference to the time chart of FIG. 2 and the flow charts of FIGS. 3 to 6. First, the processing for starting the three-phase brushless motor 1 is executed. To do.

In this start-up process, since the brushless motor 1 is operated synchronously, the control device 11 causes the six transistors U, V, W, X, Y and Z of the inverter unit 2 to turn on and off in a predetermined manner. A chopping signal for chopping the signal is output to switch the energization of the three armature windings of the brushless motor 1 to
Control the rotation.

In this case, the brushless motor 1 is gradually accelerated from a low frequency, and the position detection unit 10 outputs the position signal R0.
Is output, and the intersection of the induced voltage and the reference voltage can be detected by the position signal R0, that is, until the appropriate position signal R0 is obtained, the above processing is executed. Since the control during this synchronous operation is already known,
Detailed description thereof will be omitted.

When the brushless motor 1 is rotationally controlled for a predetermined time by the start-up process described above, the terminal voltage R of each armature winding of the brushless motor 1 is normally input to the position detector 10 (see FIG. 2 (b)). ). The position detecting section 10 divides the terminal voltage by the voltage dividing circuit 10a (signal R shown in FIG. 2B).
U), the divided signal RU and the reference voltage generating circuit 10
The comparison circuit 10c compares the reference voltage from b with the reference voltage and outputs the position signal R0 as a result of the comparison (shown in FIG. 2C).

At the timing t3 shown in FIG. 2, the control circuit 11 detects the present time ta by the edge of the first position signal R0 after the energization switching and temporarily stores it in the internal memory (step ST1), at this time ta, the time T (3
0) = T2 × (30/360) is added (step ST
2) The time ta + T (30) = t (30) is set in the compare register A inside the control circuit 11 (step ST3). Note that time T (30) = T2 × (30 /
The calculation of 360) will be described later.

Subsequently, when the edge of the input position signal R0 is detected, it is determined whether the edge is a rising edge or a falling edge (step ST4). If the edge is a rising edge, the process proceeds to step ST5 and the inside of the control circuit 11 is determined. The flag set in advance is set ("1"), and if it is a falling edge, step ST6
Proceed to and clear the flag (set it to "0").

After setting or clearing the above flags,
Time t (3 set in the above compare register A
When 0) has elapsed (time t4 shown in FIG. 2), the t (30) interrupt routine shown in FIG. 4 is executed. When the flag is set, the process proceeds from step ST20 to ST21 to turn off the signal for driving the transistor W of the inverter unit 2 (shown in FIG. 2 (f)) and turn on the signal for driving the transistor U. (Shown in FIG. 2D). At the same time, a control signal for chopping the signals for driving the transistors X, Y, Z forming the lower arm of the inverter unit 2, that is, a control signal for switching from the upper arm to the lower arm chopping is sent to the chopping unit 5. Output (step ST22).

On the other hand, when the flag is cleared, the process proceeds from step ST20 to ST23 to turn off the signal for driving the transistor Z of the inverter section 2 (shown in FIG. 2 (i)) and drive the transistor X. The signal to be turned on is turned on (shown in FIG. 2 (g)). At the same time, a control signal for chopping the signals for driving the transistors U, V, W forming the upper arm of the inverter unit 2, that is, a control signal for switching from the lower arm to the upper arm chopping is sent to the chopping unit 5. Output (step ST24).

Upon completion of the interrupt processing, the process returns to the main routine to calculate the time corresponding to the phase difference of 90 degrees, so that the time (time of one cycle) T3 between time t1 and time t3 is calculated (step ST7). ). In this case, the time tc is subtracted from the time ta to calculate the time of one cycle. The time tc corresponds to the time t1 shown in FIG.

Next, when the time T3 for one cycle is calculated,
Using this time T3, a time corresponding to a phase angle of 90 degrees from the edge of the position signal R0, T (90) = T3 × (90 /
360), and this calculation time T (90)
Is added to time ta to calculate the time at which the phase difference is 90 degrees (step ST8), and the calculated time t (90) = ta +
T (90) is set in the comparator register B (step ST9).

Subsequently, when the time t (90) set in the comparator register B has elapsed (time t5 shown in FIG. 2), the t (90) interrupt routine shown in FIG. 5 is executed. When the flag is set, the process proceeds from step ST30 to ST31, the signal for driving the transistor Y of the inverter unit 2 is turned off (shown in FIG. 2 (h)), and the signal for driving the transistor Z is turned on. (Shown in FIG. 2 (i)). At the same time, a control signal for chopping the signals for driving the transistors U, V, W forming the upper arm of the inverter unit 2, that is, a control signal for switching from the lower arm to the upper arm chopping is sent to the chopping unit 5. Output (step ST32).

On the other hand, when the flag is cleared, the process proceeds from step ST30 to ST33, the signal for driving the transistor V of the inverter section 2 is turned off (shown in FIG. 2 (e)), and the transistor W is driven. The signal to be turned on is turned on (shown in FIG. 2 (f)). At the same time, a control signal for chopping the signals for driving the transistors X, Y, Z forming the lower arm of the inverter unit 2, that is, a control signal for switching from the upper arm to the lower arm chopping is sent to the chopping unit 5. Output (step ST34).

Subsequently, upon completion of the interrupt process, the process returns to the main routine, and in order to calculate the time corresponding to the phase difference of 150 degrees, the position signal R is calculated using the time T3.
A time T (15
0) = T3 × (150/360) is calculated, and
The calculated time T (150) is added to the time ta to calculate the time with the phase difference of 150 degrees (step ST10), and the calculated time t (90) = ta + T (90) is set in the comparator register C (step ST10). ST11).

Then, the time t (150) set in the comparator register C has elapsed (FIG. 2).
At time t6), the t (150) interrupt routine shown in FIG. 6 is executed. When the flag is set, the process proceeds from step ST40 to ST41 to turn off the signal for driving the transistor U of the inverter unit 2 (shown in FIG. 2D) and turn on the signal for driving the transistor V. (Shown in FIG. 2 (e)). At the same time, a control signal for chopping the signals for driving the transistors X, Y, Z forming the lower arm of the inverter unit 2, that is, a control signal for switching from the upper arm to the lower arm chopping is sent to the chopping unit 5. It is output (step ST42).

On the other hand, when the flag is cleared, the process proceeds from step ST40 to ST43, the signal for driving the transistor X of the inverter section 2 is turned off (shown in FIG. 2 (g)), and the transistor Y is driven. The signal to be turned on is turned on (shown in FIG. 2 (h)). At the same time, a control signal for chopping the signals for driving the transistors U, V, W forming the upper arm of the inverter unit 2, that is, a control signal for switching from the lower arm to the upper arm chopping is sent to the chopping unit 5. It is output (step ST44).

Then, upon completion of the interrupt processing, the process returns to the main routine and, using the time T3 of one cycle, the time T (30) = T3 × (30/3) corresponding to the phase difference of 30 degrees.
60) is calculated (step ST12). This time T
The calculation of (30) is to be used in step ST3 when the main routine is repeated.

Subsequently, the time tb (see FIG. 2) at which the edge of the previously detected position signal R0 is detected is stored in the memory that stores the time tc at which the edge of the position signal R0 is detected two times before (time t1 shown in FIG. 2). At time t2 shown in the drawing, the time tb of the previous time is stored by changing it to the time tc of the last two times (step ST13). Further, the edge time ta (t3 shown in FIG. 2) of the position signal R0 of this time detection is written in the memory that stores the time tb of the edge of the position signal R0 of the previous detection (time t2 shown in FIG. 2), that is, This is because it is necessary to reserve one memory in order to obtain the edge time of the position signal.

When the edge of the input position signal R0 is detected, the main routine is executed again and the current time ta of the edge detection (time t7 shown in FIG. 2) is stored in the memory (step ST1). Time T (30) corresponding to the phase difference of 30 degrees calculated in step ST12
= T3 × (30/360) is added to the current time ta (step ST2), and this time ta + T (30) = t
(30) is set in the comparator register A (step ST3). In this way, the main routine of FIG. 3 and the interrupt routine of FIGS. 4 to 6 are executed and repeated as described above.

More specifically with reference to the time chart of FIG. 2, since the edge of the position signal R0 is rising at time t7, the flag is cleared (step ST6) and set in the comparator register. When the time t (30) has elapsed (time t8 shown in FIG. 2), the t (30) interrupt routine shown in FIG. 4 is executed.

In this case, since the flag is not set, the signal for driving the transistor Z of the inverter section 2 is turned off (as shown in FIG. 2 (i)) and the signal for driving the transistor X is turned on as described above. (Figure 2 (g)
Shown in). At the same time, a control signal for chopping the signals for driving the transistors U, V, W forming the upper arm of the inverter unit 2, that is, a control signal for switching from the lower arm to the upper arm chopping is sent to the chopping unit 5. Output.

In addition, the phase angle 9 from the edge of the position signal R0.
Time 0 ° delayed t (90) = t7 + T4 × (90/36
0) is calculated, and when the time t (90) elapses (time t9 shown in FIG. 2), the (150) interrupt routine shown in FIG. 5 is executed.

In this case, since the flag is not set, the signal for driving the transistor V of the inverter section 2 is turned off and the signal for driving the transistor W is turned on as described above. At the same time, a control signal for chopping the signals for driving the transistors X, Y, Z forming the lower arm of the inverter unit 2, that is, a control signal for switching from the upper arm to the lower arm chopping is sent to the chopping unit 5. Output.

Furthermore, time t (150) = T7 + T4 × (15) which is delayed by a phase angle of 150 degrees from the edge of the position signal R0.
0/360) is calculated, and when this time t (150) has elapsed, the interrupt routine shown in FIG. 6 is executed.

In this case, since the flag is not set, the signal for driving the transistor X of the inverter section 2 is turned off (as shown in FIG. 2 (g)) and the signal for driving the transistor Y is turned on as described above. (Figure 2 (h)
Shown in). At the same time, a control signal for chopping the signals for driving the transistors U, V, W forming the upper arm of the inverter unit 2, that is, a control signal for switching from the lower arm to the upper arm chopping is sent to the chopping unit 5. Output.

In the above embodiment, the position signal R0
The energization of the armature winding is switched at timings of phase angles of 30 degrees, 90 degrees, and 150 degrees (phase difference) from the edge of, but, for example, the phase difference is 30 degrees, 90 degrees depending on the rotation speed and the load state. And 150 degrees, the phase difference is set so that the operation efficiency of the brushless motor 1 is maximized, that is, the time corresponding to the phase difference is calculated from the edge of the position signal R0, and when this calculation time elapses. The energization of the armature winding may be switched.

In this way, one terminal voltage (induced voltage) of the brushless motor 1 is compared with a predetermined reference value, a position signal is obtained at the timing of the intersection (neutral point) which is the result of this comparison, and this position signal is obtained. Is input to the microcomputer of the control circuit 11, and the time (T1 to T6 shown in FIG. 2) between the edges of the position signal is measured by this microcomputer, and a predetermined phase angle (for example, 30 degrees, 90 degrees) from the edge is measured. Degrees (150 degrees) and a delay time (T (30), T (90), T (150) shown in FIG. 2) are calculated, and three electric machines are used as the position detection timing of the rotor 1a when these calculated times elapse. Switch the energization of the child winding. Further, in order to obtain the position signal, the voltage divider circuit 10a and the comparator circuit 10c for only one phase and the reference voltage generation circuit 10b are provided.

Therefore, it is possible to obtain an appropriate rotor position detection timing without using an integrating circuit or the like, to enable optimal energization switching, to maximize operating efficiency, and to reduce the number of parts. Less,
It can be done cheaply.

[0056]

As described above, according to the present invention, the position of the rotor of a three-phase brushless motor is detected,
A brushless motor control method and device for switching energization of three armature windings based on the position detection timing is obtained by comparing a terminal voltage (induced voltage) of one armature winding with a predetermined reference voltage. When the energization switching timings of the three armature windings are obtained based on the timing of the intersecting points, the predetermined phase angle delay timing (optimum energizing switching time) is obtained from the intersections, and the armature winding By controlling the rotation of the brushless motor by switching the energization of the wire, it is possible to obtain an appropriate rotor position detection timing, that is, the energization of the armature winding can be optimally switched, and the rotation speed and Optimal operation (operation with maximum efficiency) can be enabled according to the load state.

As a circuit for obtaining the timing of the intersection, an integrating circuit or the like may not be used, and a voltage dividing circuit for one phase and a comparison circuit and a reference voltage generating circuit may be used, and the position of the timing of the intersection may be used. The signal is input to the control circuit (microcomputer), and the timing for switching the energization of the armature winding is obtained by this control circuit, so not only the circuit configuration is simplified and the number of parts is reduced, but also the number of manufacturing steps There is a useful effect that it is possible to reduce the cost and eventually the cost.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a brushless motor control device according to an embodiment of the present invention.

FIG. 2 is a schematic time chart diagram for explaining the operation of the controller for the brushless motor shown in FIG.

FIG. 3 is a schematic flowchart illustrating the operation of the controller for the brushless motor shown in FIG.

FIG. 4 is a schematic flowchart illustrating the operation of the brushless motor control device shown in FIG. 1.

5 is a schematic flow chart diagram for explaining the operation of the controller of the brushless motor shown in FIG. 1. FIG.

FIG. 6 is a schematic flowchart illustrating the operation of the brushless motor control device shown in FIG. 1.

FIG. 7 is a schematic block diagram of a conventional brushless motor control device.

8 is a schematic time chart diagram for explaining the operation of the controller for the brushless motor shown in FIG. 7. FIG.

[Explanation of symbols]

1 Brushless Motor (DC Brushless Motor) 1a Rotor (of Brushless Motor 1) 2 Inverter Section 5 Chopping Section 6 Driver Section 4, 11 Control Circuit (Microcomputer) 10 Position Detection Section 10a Voltage Dividing Circuit 10b Reference Voltage Generation Circuit 10c Comparison Circuit R, S, T Terminal voltage of armature winding R0 Position signal U, V, W Switching element (upper arm transistor) X, Y, Z switching element (lower arm transistor)

Claims (2)

[Claims] 1. When the DC power source is switched by the inverter means and applied to the armature winding of a three-phase brushless motor, the inverter means is driven based on the position detection of the rotor of the brushless motor to drive the electric machine. A method of controlling a brushless motor that switches energization of a child winding, wherein one terminal voltage of the terminal voltage (induced voltage) of the armature winding is compared with a predetermined reference voltage, and the comparison result indicates an intersection point. While calculating the time corresponding to the predetermined phase angle delay,
A method for controlling a brushless motor, characterized in that a next energization switching timing of the armature winding is obtained based on the calculated time, and a signal for driving the inverter means is generated in accordance with the energization switching timing. . 2. When the DC power source is switched by the inverter means and applied to the armature winding of the three-phase brushless motor, the inverter means is driven based on the position detection of the rotor of the brushless motor to drive the electric machine. A controller of a brushless motor that switches energization of a child winding, wherein one terminal voltage of the terminal voltage (induced voltage) of the armature winding is divided, and the divided voltage and a predetermined reference voltage are divided. The position detection means for comparing and outputting the position signal at the timing of the intersection as the comparison result and the time corresponding to the predetermined phase angle from the edge of the output position signal are obtained, and the armature winding is calculated based on the calculated time. A control means for obtaining the next energization switching timing of the wire and generating a signal for driving the inverter means at the energization switching timing, and disconnecting the energization of the armature winding. Instead the control device for a brushless motor which is characterized in that so as to rotate control the brushless motor.