KR102444416B1 - Soft switching method of motor providing kick-start - Google Patents

Abstract

The present invention provides a soft switching method of a motor that provides a kickstart, comprising the steps of: driving a motor according to a pulse width modulation signal having a duty ratio according to a preset first initial value; When the rotor position is changed within a preset range, it is set to a stop state, and when it is changed beyond a preset range, it is determined as a rotating state; When the motor is determined to be in a stopped state, the pulse for driving the motor Blocking the output of the width modulation signal by a preset delay time, and after the delay time has elapsed, the motor is re-driven according to the pulse width modulation signal having a duty ratio of a second initial value greater than the first initial value and, by re-sensing the position of the rotor of the motor, and when the motor is detected as being in a rotating state, the duty ratio of a pulse width modulation signal for driving the motor from the second initial value to a preset target value in stages It is characterized in that it comprises the step of increasing or decreasing.
Accordingly, it is possible to realize a stable system of the motor by allowing an initial duty drive suitable for the motor system to be found while satisfying the initial starting torque of the motor.

Description

SOFT SWITCHING METHOD OF MOTOR PROVIDING KICK-START

The present invention relates to a method for soft switching of a motor, and more particularly, to a method for switching a motor that provides a kickstart to satisfy an initial starting torque of a motor without straining a power switch of the motor.

In the case of a motor or power supply having a switch control method, a PWM (Pulse Width Modulation) signal, which is a gate driving signal, for a certain period of time (about 10 ms) in order to prevent the power switch from being damaged by an inrush current that is introduced during initial operation. After stabilizing the power switch by gradually increasing the duty width of This control method is called soft start, and the period in which the power switch is stabilized for a certain period of time is called soft start time. By implementing this soft-start function, the deterioration of the power switch is prevented and the service life of the switch is extended.

In general, in the case of motor control, in performing the duty control of PWM, which controls the speed of the motor according to the input control signal, unlike the switch control type power supply device, which does not change significantly after the initial operation, it depends on the input control signal. A large change is required. Therefore, a change in the duty control width for an instantaneous speed change may cause a reduction in the life span of the switch for controlling the motor and cause a motor failure.

According to the prior art, a converter for soft start has been proposed in order to prevent a large change in duty, but there is a problem that the switching step for soft start or soft switching cannot be easily adjusted by this prior art There is a disadvantage in that it is difficult to respond to a change in duty after the initial driving.

US 10-2007-0118752 A US 10-2008-0095567 A

An object of the present invention is to solve the above problems, and it is an object of the present invention to provide a method for soft switching of a motor that provides a kickstart to satisfy the initial starting torque of the motor without straining the power switch of the motor.

According to an aspect of the present invention, there is provided a soft switching method for a motor that provides a kickstart, comprising the steps of: driving the motor according to a pulse width modulation signal having a duty ratio according to a predetermined first initial value; , detecting the rotor position of the motor and determining that the rotor position is in a stopped state when the position is changed within a preset range and is in a rotating state when it is changed beyond the preset range; blocking the output of the pulse width modulation signal for driving the motor by a preset delay time so that the torque supplied to the motor rapidly decreases and approaches zero when it is determined, and after the delay time has elapsed Re-driving the motor according to a pulse width modulation signal having a duty ratio of a second initial value greater than a first initial value; and increasing or decreasing the duty ratio of the pulse width modulation signal for driving the motor from the second initial value to a preset target value in stages.

According to the present invention, it is possible to realize a stable system of a motor by allowing an initial duty drive suitable for a motor system to be found while satisfying the initial starting torque of the motor.

In addition, according to the present invention, since the switching duty ratio of the pulse width modulation signal is increased or decreased step by step from the duty ratio at the time when the initial driving of the motor is started to the ideal target duty ratio of the motor, there is no strain on the power switch of the motor. .

1 is a flowchart illustrating a method for soft switching of a motor providing a kickstart according to an embodiment of the present invention;
2 is a block diagram schematically showing a driving circuit of a motor to which FIG. 1 is applied;
3 is a block diagram schematically illustrating an internal configuration of the duty ratio increase/decrease unit of FIG. 2 .

Specific details including the problems to be solved for the present invention as described above, the means for solving the problems, and the effects of the invention are included in the embodiments and drawings to be described below. Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. Like reference numerals refer to like elements throughout.

1 is a flowchart illustrating a method of soft switching of a motor providing a kickstart according to an embodiment of the present invention, and the method of soft switching of a motor providing a kickstart according to an embodiment of the present invention is shown in FIG. It can be implemented using the driving circuit of the motor.

Hereinafter, a method of soft switching of a motor for providing a kickstart according to an embodiment of the present invention will be described in detail with reference to the drawings.

First, the motor 10 is driven according to a pulse width modulation (PWM) signal having a duty ratio according to a preset first initial value (S100).

For example, the PWM generating unit 50 generates a PWM signal having a duty ratio according to the first initial value and outputs it to the driving unit 60 , and the driving unit 60 based on the duty ratio included in the input PWM signal. The motor 10 is driven.

In the method of soft switching of a motor providing kickstart according to an embodiment of the present invention, a target value for a duty ratio of a PWM signal corresponding to a driving command of the motor is preset, and the first initial value is the target value. It is preferable to set it smaller than the value.

For example, when the target value is set to 10%, the first initial value may be set to 2.5%.

Next, by detecting the rotor position of the motor, when the rotor position is changed within a preset range, it is set to a stop state, and when it is changed beyond the preset range, it is determined as a rotating state (S200).

For example, if the preset range is 0° to 10°, if the angle corresponding to the rotor position of the motor 10 sensed by the sensing unit 20 is 8°, the motor 10 is in a stopped state. judge

Next, when it is determined that the motor is in a stopped state, the output of the PWM signal for driving the motor is cut off by a preset delay time (S300), and after the delay time has elapsed, a second value greater than the first initial value is blocked. 2 The motor is re-driven according to the PWM signal having the duty ratio of the initial value (S400).

In this case, the torque supplied to the motor 10 during the delay time sharply decreases and approaches zero. 10), the amount of change in momentum, that is, the amount of impact, is increased to instantaneously generate a high maximum torque in the motor 10, so that even when the increase in the duty ratio is small, it is possible to effectively meet the initial starting torque of the motor do.

Next, the duty ratio of the PWM signal for driving the motor is increased or decreased in stages from the second initial value to a preset target value when the motor is detected as rotating by re-sensing the position of the rotor ( S600).

Here, the increasing/decreasing step (S600) includes calculating a difference value between the second initial value and the target value (S601), and bit-right shifting the difference value by a preset bit value to obtain a step size. It may include step S602 and step S603 of increasing/decreasing in stages from the second initial value to the target value based on a plurality of increasing/decreasing steps according to increasing/decreasing by the step size.

At this time, the increasing/decreasing step ( S600 ) is performed by the duty ratio increase/decrease unit 40 of FIG. 2 , which includes a signal detector 110 and a subtractor 120 as shown in FIG. 3 . ), the shifter 130 , the adder/subtractor 150 , the soft switching register 160 , the operand register 170 , the multiplexer 180 , and the step control unit 190 may be provided.

Here, the signal detector 110 binarizes and stores the second initial value and the target value, the subtractor 120 calculates a difference between the stored second initial value and the target value, and the shifter 130 A step size is obtained by bitwisely calculating the calculated difference value by a preset bit value, the adder 150 adds or subtracts the input binary value by the step size, and the soft switching register 160 adds or subtracts the The output value is stored and output, and the operand register 170 receives the output value of the soft switching register 160 and changes or maintains the stored operand value to the output value of the soft switching register 160, and the multiplexer 180 is the first 2 The initial value and the operand value are received from the operand register 170 to output the second initial value or the operand value to the adder/subtractor 150 based on a selection signal, and the step control unit 190 controls the second initial value A selection signal is generated based on a plurality of increasing/decreasing steps according to the step size from to the target value, and the generated selection signal is provided to the multiplexer 180 .

Hereinafter, a detailed operation example of performing the increasing/decreasing step ( S600 ) using the duty ratio increasing/decreasing unit 40 will be described with reference to FIG. 3 .

If the signal detector 110 receives 010100 (a decimal value of 20) composed of 6 bits as the second initial value and 101000 (a decimal value of 40) as the target value, the subtractor 120 performs 101000 and 010100 By calculating the difference between , a difference value of 010100 (decimal value is 20) is calculated.

Thereafter, if the shifter 130 performs bit right operation on the difference value 010100 by a preset bit value (eg, 1 bit) for two-step soft switching, a step size of 001010 (decimal value is 10) can be obtained. .

At this time, the switching step register 140 stores the step size of 000101.

Meanwhile, the multiplexer 180 receives the second initial value of 010100 (the decimal value is 20) from the signal detector 110 and receives the first selection signal generated by the step control unit 190 to receive the second initial value. 010100 is output as the first step (step1).

The adder 150 increases the step size by 001010 (10 in decimal) from 010100 (20 in decimal) output from the multiplexer 180 as the first step, and stores 011110 (30 in decimal) as the first step (step1). do.

The operand register 170 stores 000000, which is a value of 0 for each bit, as a pre-stored operand value in the first step (step 1), and the output value is 011110 (30 in decimal) from the addition/subtractor 150 or the soft switching register 160 ), as a second step (step2), the previously stored operand value (000000) is changed to the output value (011110) of the soft switching register 160, and the changed operand value (011110 (30 in decimal)) is output to the multiplexer 180. do.

The multiplexer 180 receives an operand value from the operand register 170, and the step control unit 190 causes the multiplexer 180 to output the operand value of the operand register 170 in the second step (step2). , and provides a second selection signal to the multiplexer 180 .

The multiplexer 180 outputs 011110 (30 in decimal) as the second step (step 2) according to the second selection signal.

Thereafter, the addition/subtractor 150 operates to increase the value by the step size from the output of the multiplexer 180 and outputs 101000 (40 in decimal), which is the output value of the second step (step2), and the soft switching register 170 is this Save the value.

The step controller 190 applies a disable signal to the operand register 170 in the last step (step2) of the increase/decrease steps.

In this case, the output value of the operand register 170 is maintained at 011110, and the addition/subtractor 150 outputs 101000 (40 in decimal), which is a value obtained by adding the step size from 011110 to the output value of the soft switching register 160. 101000 (40 in decimal) is maintained.

Accordingly, since the switching duty ratio of the pulse width modulation signal is increased or decreased step by step from the duty ratio at the time when the initial driving of the motor is started to the ideal target duty ratio of the motor, there is no strain on the power switch of the motor.

On the other hand, in the soft switching method of the motor providing kickstart according to another embodiment of the present invention, when the first step and the second step are in a preset state, the blocking step (S300) and the re-driving step ( S400), the method may further include stepping up from the first step to the second step.

Here, the first step includes a plurality of increasing/decreasing steps of increasing or decreasing stepwise from the first initial value to the target value, and the second step includes a plurality of increasing/decreasing steps increasing/decreasing stepwise from the second initial value to the target value. It may include an increase/decrease step.

In this case, it is preferable that the second step has a lower priority than the first step.

For example, the step selection unit 30 detects the position of the rotor of the motor 10 by the detection unit 20 in a state in which the first step is set to the initial state according to the priority, and the motor 10 is stopped. If it is determined that the step selector 30 maintains the initial state, but if it is determined that the motor 10 is in the rotating state, the step selector 30 steps up in the first step and The second step is selected.

Meanwhile, according to the foregoing, in the case of the soft switching method of a motor providing kickstart according to an embodiment of the present invention, the first initial value and the second initial value are in a preset state, or a second initial value having the first initial value Although only a preset state is considered in the first step and the second step having the second initial value, the present invention is not limited thereto, and initial values or steps may be added as necessary.

Accordingly, as described above, by using the soft switching method of the motor providing kickstart according to the present invention, it is possible to find the initial duty driving suitable for the motor system while satisfying the initial starting torque of the motor. It not only makes it possible to implement a stable system, but also increases or decreases the switching duty ratio of the pulse width modulation signal from the duty ratio at the time the initial driving of the motor starts to the ideal target duty ratio of the motor. won't go

As mentioned above, although the present invention has been described in detail through preferred embodiments, the present invention is not limited thereto and may be variously practiced within the scope of the claims.

10: motor 20: sensing unit
30: step selection unit 40: duty ratio increase/decrease unit
50: PWM generating unit 60: driving unit
110: signal detector 120: subtractor
130: shifter 135: bit value setting unit
140: switching step register 150: addition and subtraction
160: soft switching register 170: operand register
180: multiplexer 190: step control unit

Claims (3)

driving a motor according to a pulse width modulation signal having a duty ratio according to a preset first initial value;
detecting the rotor position of the motor and determining that the rotor position is in a stopped state when the position is changed within a preset range and is in a rotating state when the position of the rotor is changed within a preset range;
blocking the output of the pulse width modulation signal for driving the motor by a preset delay time so that the torque supplied to the motor rapidly decreases and approaches zero when it is determined that the motor is in a stopped state;
re-driving the motor according to a pulse width modulation signal having a duty ratio of a second initial value greater than the first initial value after the delay time has elapsed; and
Step by step increasing/decreasing a duty ratio of a pulse width modulation signal for driving the motor from the second initial value to a preset target value when the motor is detected as rotating by re-sensing the rotor position of the motor includes,
A first step comprising a plurality of increasing/decreasing steps of increasing/decreasing in steps from the first initial value to the target value, and a plurality of increasing/decreasing steps of increasing/decreasing stepwisely from the second initial value to the target value, wherein the first When the second step having a lower priority than the step is in a preset state,
Between the step of shutting down and the step of re-driving,
The soft switching method of the motor providing a kickstart further comprising the step of step-up (step up) from the first step to the second step.
According to claim 1,
The increasing or decreasing step is
calculating a difference between the second initial value and the target value;
calculating a step size by performing a bit-right shift operation on the difference value by a preset bit value; and
and increasing or decreasing from the second initial value to the target value in stages based on a plurality of increasing/decreasing steps according to the step size.





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