JP2008289238A - Motor controller and readhesion control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a new control method which separates detection of occurrence of idling slip from execution of readhesion control. <P>SOLUTION: When the peripheral speed V of a driving wheel increases due to occurrence of idling slip of the driving wheel and the speed difference Vd from a reference speed Vm reaches a predetermined threshold Vs1 at time t1, occurrence of idling slip is detected. When the peripheral speed V increases furthermore and the speed difference Vd from the reference speed Vm reaches a predetermined threshold Vs2 at time t2, readhesion control is executed. A threshold αs2 is determined depending on the tangential force coefficient μ of the driving wheel at the timing of idling slip detection. More specifically, when the tangential force coefficients μ is relatively large, Vs2=Vs1 is satisfied and when idling slip detection takes place, readhesion control is executed immediately. When the tangential force coefficients μ is relatively small, Vs2>Vs1 is satisfied and the timing of readhesion control is delayed as compared with that in prior art. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric motor control device that controls an electric motor that drives a moving wheel of an electric vehicle, detects occurrence of idling of the moving wheel, and performs re-adhesion control of the moving wheel, and a re-adhesion control method thereof.

  As electric cars, trains, electric cars, and the like are known. Hereinafter, trains (powered vehicles) will be described as typical examples. The train is accelerated and decelerated by the tangential force between the wheels and rails (also called adhesive force). If the generated torque of the electric motor is in the range of tangential force or less, adhesion running is performed, but if the tangential force is exceeded, idling or gliding (hereinafter referred to as “idling gliding”) occurs. In the case of idling, the control for reducing the generated torque of the electric motor to return to the sticking running, that is, the re-sticking control is performed (for example, refer to Patent Document 1).

Therefore, torque control that maintains effective adhesion performance and does not cause idling or rapid and optimum re-adhesion torque control after idling is required. However, in order to maintain the adhesion performance, it is necessary to obtain a tangential force. As a technique for estimating the tangential force coefficient, for example, the technique of Patent Document 2 is known.
JP 2002-44804 A Japanese Patent Laid-Open No. 11-252716

  However, most of the developments and researches related to conventional re-adhesion control are related to a method for quickly detecting the occurrence of idling and the method for prompt re-adhesion control after detecting the occurrence of idling. In other words, it is an implicit premise that the re-adhesion control is promptly activated in the event of idling.

  The present invention has been made in view of the above-described problems, and proposes a new control method that separates the detection of the occurrence of idling and the activation of re-adhesion control.

The first invention for solving the above-described problems is
An electric motor control device (for example, the electric motor in FIG. 3) that controls the electric motor (for example, the electric motor 10 in FIG. 3) that drives the driving wheel of the electric vehicle, detects the occurrence of idling of the moving wheel, and performs re-adhesion control of the moving wheel. A control device 40),
Tangential force coefficient equivalent value detecting means for detecting the tangential force coefficient equivalent value of the driving wheel (for example, the μ calculating device 41 in FIG. 3);
1) A first speed difference reference condition (for example, a threshold value Vs2 set in the comparator 4243 in FIG. 4) having the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values, and / or 2 ) Satisfying the re-adhesion control activation condition including at least a first circumferential acceleration reference condition (for example, the threshold value αs2 set in the comparator 4244 in FIG. 4) that uses the circumferential acceleration of the moving wheel as a determination target value. Trigger condition matching detection means to detect (for example, trigger command unit 424 in FIG. 4);
Re-adhesion control activating means (for example, a return command unit 425 in FIG. 4) for activating the re-adhesion control in response to detection by the activation condition match detection means;
With
An electric motor control device further comprising activation condition variable means (for example, parameter switching unit 427 in FIG. 4) for changing the activation condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. is there.

As another invention,
A re-adhesion control method for detecting occurrence of idling of the moving wheel and performing re-adhesion control of the moving wheel when controlling an electric motor that drives a driving wheel of an electric vehicle,
A tangential force coefficient equivalent value detecting step for detecting a tangential force coefficient equivalent value of the driving wheel;
1) a first speed difference reference condition that uses the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values; and / or 2) a first periphery that uses the peripheral acceleration of the moving wheel as a determination target value. An activation condition match detection step for detecting that the activation condition of the re-adhesion control including at least an acceleration reference condition is satisfied;
A re-adhesion control activation step for activating the re-adhesion control in response to detection by the activation condition match detection step;
Including
The re-adhesion control method may further include an activating condition variable step of changing the activating condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detecting step.

  According to the first aspect of the invention, the re-adhesion control is activated when it is detected that the activation condition is satisfied. The activation condition is varied based on the detected value corresponding to the tangential force coefficient of the driving wheel. The The value corresponding to the tangential force coefficient is not only the tangential force coefficient itself, but also the same variation as the variation of the tangential force coefficient, such as the tangential force, the adhesive force, and the electric current value of the motor (for example, torque current). This is a value (a value that is almost linear with the tangential force coefficient) and can be handled equivalently or substantially equivalent to the tangential force coefficient.

  Re-adhesion control is activated during idling. The idling occurs even if the tangential force coefficient equivalent value is high or low. If re-adhesion control is performed when the value corresponding to the tangential force coefficient of the running wheel that is idling is relatively low, the tangential force coefficient equivalent value during re-adhesion is relatively low due to torque reduction by re-adhesion control. The tangential force coefficient equivalent value is lower than the tangential force coefficient equivalent value, and the adhesive force during re-adhesion is reduced.

  However, as will be described later, when idling with a relatively low tangential force coefficient equivalent value is continued, the tangential force coefficient equivalent value can increase. Thus, according to the first invention and the like, the activation condition for the re-adhesion control is varied based on the tangential force coefficient equivalent value, so that the timing of the re-adhesion control activation is delayed when the tangential force coefficient equivalent value is low. Is possible. Thereby, the continuation of idling is allowed and the increase of the tangential force coefficient equivalent value is promoted, so that the adhesive force at the time of re-adhesion can be increased.

Moreover, 2nd invention is the motor control apparatus of 1st invention, Comprising:
An idle running detection means (for example, an idle running detection unit 423 in FIG. 4) for detecting occurrence of idle running of the driving wheel is further provided,
The activation condition varying means is an electric motor control device that varies the activation condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means when the idle running detection means is detected. is there.

  According to the second aspect of the present invention, the re-adhesion control activation condition can be varied based on the value corresponding to the tangential force coefficient phase when the occurrence of idling of the driving wheel is detected.

The third invention is the electric motor control device of the first invention,
An idling detection means (for example, idling detection unit 423 in FIG. 4) for detecting occurrence of idling of the driving wheel;
There is a possibility that the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detecting means when the occurrence of idling of the driving wheel is detected by the idle running detection means will increase when the idle running is continued. Immediately running idle running means that activates the re-adhesion control in response to detection by the idle running detection means when the predetermined range is not within a predetermined allowable continuous range (for example, the activation command unit in FIG. 4) 424),
Is an electric motor control device further provided.

  If the value corresponding to the tangential force coefficient at the time of idling is not within the continuation allowable range set in advance as the range of values that may rise if idling is continued, the idling There is little possibility of an increase in the value corresponding to the tangential force coefficient. Depending on the activation conditions, continuation of idling can be allowed even in such a case, but according to the third invention, continuation of idling in such a case can be prevented.

Moreover, 4th invention is the electric motor control apparatus of 2nd or 3rd invention, Comprising:
Non-activation detecting means for detecting that the re-adhesion control is not activated by the re-adhesion control activating means until a predetermined time elapses after detection by the idling / sliding detection means (for example, the activation command unit 424 in FIG. 4). )When,
Forced activation means (for example, activation command unit 424 in FIG. 4) for forcibly activating the re-adhesion control in response to detection by the non-activation detection means;
Is an electric motor control device further provided.

  According to the fourth aspect of the invention, the re-adhesion control is forcibly activated when the re-adhesion control is not activated until a predetermined time has elapsed since the detection of the idling. There is also a risk that the life of the wheel may be shortened due to friction and wear with the rail due to continuous idling. However, according to the fourth aspect of the present invention, when the re-adhesion control is not activated until the predetermined time has elapsed since the detection of the occurrence of idling, the re-adhesion control is forcibly activated. Excessive continuation of gliding can be prevented.

The fifth invention is the motor control device according to any one of the first to fourth inventions,
The activation condition varying means includes a continuation allowable range that is determined in advance as a range of values that may increase when the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means continues idling. When the motor is in the motor, the motor control device changes the activation condition to a condition that allows the idling to be continued as compared with a case where the motor does not fall within the allowable continuous range.

  If the value corresponding to the tangential force coefficient at the time of idling is within the continuation allowable range determined in advance as the range of values that may rise when idling is continued, the idling There is a high possibility of an increase in the value corresponding to the tangential force coefficient. Therefore, according to the fifth aspect, it is possible to allow the idling to be continued when the value corresponding to the tangential force coefficient when the occurrence of such idling is detected is within the allowable continuation range.

The sixth invention is the electric motor control device of the first invention,
Idle running detection means (for example, idle detection unit 423 in FIG. 9) for detecting occurrence of idle running of the driving wheel;
Idle running high frequency generation detecting means (for example, high frequency occurrence detector 431 in FIG. 9) for detecting that the detection frequency by the idle running detection means matches a predetermined high frequency condition;
Further comprising
The activation condition varying means varies the activation condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means when the idle running high frequency occurrence detection means is detected. An electric motor control device.

  According to the sixth aspect of the present invention, when the detection frequency of the occurrence of idling meets the predetermined high frequency condition, the activation condition is varied based on the detected tangential force coefficient equivalent value. It can be said that a state where the wheel is driven at a high torque while the adhesive force is small is a state where idling is likely to occur. Moreover, it can be said that the state where the adhesive force is small is a state where the tangential force coefficient is low. Therefore, there is a possibility that the state in which idling occurs frequently has a low tangential force coefficient. According to the sixth aspect of the present invention, the activation condition can be changed in such a state, and the re-adhesion control activation control suitable for the state can be realized.

Various methods are conceivable as the method for changing the activation condition in each of the above-described inventions.
For example, as a seventh invention, the electric motor control device according to any one of the first to sixth inventions,
The activation condition includes at least the first speed difference reference condition,
In the first speed difference reference condition, a speed difference between a peripheral speed of the driving wheel and a traveling speed of the electric vehicle or a threshold of a slip ratio is defined as a condition.
The activation condition varying means may constitute an electric motor control device that varies the activation condition by increasing or decreasing the threshold value.

In this case, as an eighth invention,
The activation condition varying means may constitute an electric motor control device that increases the threshold value as the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means decreases.

Further, as a ninth invention, the electric motor control device according to any one of the first to eighth inventions,
The activation condition includes at least the first circumferential acceleration reference condition,
In the first circumferential acceleration reference condition, a threshold value of the circumferential acceleration of the driving wheel is defined as a condition,
The activation condition varying means may constitute an electric motor control device that varies the activation condition by increasing or decreasing a threshold value of the circumferential acceleration.

In this case, as a tenth invention, the electric motor control device of the ninth invention,
The activation condition varying means may constitute an electric motor control device that increases the threshold value of the circumferential acceleration as the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means is smaller.

The eleventh invention is the electric motor control device according to any one of the first to tenth inventions,
The activation condition varying means may further constitute an electric motor control device that varies the activation condition based on the traveling speed of the electric vehicle.

According to the eleventh aspect, in addition to the value corresponding to the tangential force coefficient of the driving wheel, the activation condition is further varied based on the traveling speed of the electric vehicle.
For this reason, it is possible to realize appropriate change of the activation condition according to the relationship between the traveling speed of the electric vehicle and the tangential force coefficient equivalent value.

  Moreover, in the electric motor control apparatus of each invention described above, the activation of the re-adhesion control is controlled based on the value corresponding to the tangential force coefficient, but control other than the activation may be performed.

For example, as a twelfth invention, the electric motor control device according to any of the first to eleventh inventions,
B) A second speed difference reference condition (for example, a threshold value Vr set in the comparator 4251 in FIG. 4) having the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values, and / or ) At least a second circumferential acceleration reference condition (for example, a threshold value αr set in the comparator 4252 in FIG. 4) having the circumferential acceleration of the moving wheel as a determination target value, A return condition coincidence detecting means (for example, a return command unit 425 in FIG. 4) for detecting that the return condition for starting the return operation of the adhesive control is satisfied;
Re-adhesion control return means (for example, the re-adhesion controller 428 in FIG. 4) for starting the return operation of the re-adhesion control activated by the re-adhesion control activating means in response to detection by the return condition match detection means;
A return condition variable means for changing the return condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means (for example, the parameter switching unit 427 in FIG. 4);
It is good also as comprising the electric motor control apparatus further provided with.

According to the twelfth aspect, when it is detected that the return condition is satisfied, the return operation of the activated re-adhesion control is started.
That is, based on the tangential force coefficient equivalent value, it is possible to control not only the re-adhesion control activation control but also the start of the re-adhesion control return operation.

Further, as a thirteenth invention, the electric motor control device according to any one of the first to twelfth inventions,
Torque reduction speed variable means (for example, parameter switching unit 427 in FIG. 4) that varies the torque reduction speed, which is a control parameter for the re-adhesion control, based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. ) May be configured.

  According to the thirteenth aspect, the torque reduction speed, which is a control parameter for the re-adhesion control, can be varied based on the detected tangential force coefficient equivalent value.

Further, as a fourteenth invention, the electric motor control device according to any one of the first to thirteenth inventions,
Return time variable means (for example, parameter switching unit 427 in FIG. 4) for changing the return time, which is a control parameter of the re-adhesion control, based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. Furthermore, it is good also as comprising the provided motor control apparatus.

  According to the fourteenth aspect of the present invention, the return time as the re-adhesion control parameter can be varied based on the detected tangential force coefficient equivalent value.

  According to the present invention, since the re-adhesion control activation condition is varied based on the tangential force coefficient equivalent value, the re-adhesion control activation timing can be delayed when the tangential force coefficient equivalent value is low. As a result, the detection of the occurrence of idling and the activation of re-adhesion control, such as allowing the idling to continue and encouraging the increase in the value corresponding to the tangential force coefficient, can increase the adhesion force during re-adhesion. A new re-adhesion control method can be realized.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following, the case where the present invention is applied to a train which is a kind of electric car will be described, but embodiments to which the present invention can be applied are not limited thereto.

[principle]
In a train, when the occurrence of idling of a driving wheel driven by an electric motor is detected, re-adhesion control is performed to reduce the torque (current) of the electric motor and re-adhere the moving wheel to the track, and then restore the torque. As described above, in the conventional re-adhesion control, the re-adhesion control is activated (started) as soon as the occurrence of idling is detected.

  On the other hand, in the present embodiment, when the occurrence of idling is detected, the re-adhesion control is not necessarily activated immediately, but according to the tangential force coefficient μ of the driving wheel at the time when the occurrence of idling is detected. The timing for activating the re-adhesion control is varied. That is, according to the tangential force coefficient μ, (a) a control pattern that activates re-adhesion control immediately in the same manner as in the prior art, and (b) delays the timing for initiating re-adhesion control to continue idling for a certain amount of time. Switch between permissible control patterns. Specifically, when the tangential force coefficient μ is relatively large, (a) the re-adhesion control is activated immediately, and when the tangential force coefficient μ is relatively small, (b) the re-adhesion control is activated. Delay.

ここで、Ｆは車輪周引張力［Ｎ］、ｍは回転慣性質量［ｋｇ］、αは車輪周加速度［ｍ／ｓ^２］、Ｗ_０は静止輪重［Ｎ］である。
また、車輪周引張力Ｆは、式（２）で与えられる。

ここで、Ｇは歯車比、Ｒは車輪半径［ｍ］、τ_ｅは電動機の発生トルク［Ｎｍ］である。 The tangential force coefficient μ is calculated by the equation (1).

Here, F is the wheel circumferential tensile force [N], m is the rotational inertial mass [kg], α is the wheel circumferential acceleration [m / s ² ], and W ₀ is the stationary wheel weight [N].
Further, the wheel circumferential tensile force F is given by Expression (2).

Here, G is the gear ratio, R is the wheel radius [m], and τ _e is the generated torque [Nm] of the motor.

In the equations (1) and (2), the gear ratio G, the wheel radius R, the rotational inertia mass m, and the stationary wheel load W ₀ are known values determined by the specifications of the vehicle. Further, the wheel circumferential acceleration α and the generated torque τ _e are values that change as the train travels. The generated torque τ _e can be calculated from the torque current component Iq of the electric motor, for example.

  FIG. 1 is a diagram showing test results when the Shinkansen train is run at a high speed test at about 340 [km / h]. In the test, among the axes of the bogie of the Shinkansen train, when the occurrence of idling was detected for the axis to be tested, idling was continued without activating readhesion control immediately. The figure shows the characteristics of the tangential force coefficient μ with respect to the sliding speed during the occurrence (continuation) of idling. The tangential force coefficient μ was calculated using the formulas (1) and (2) from the measured value of the torque current component of the electric motor. Moreover, about the said axis | shaft, only the characteristic (1)-(7) with respect to each of the seven idling runs among many idling slides which generate | occur | produced during test running is shown.

  If the generated idling is continued, the sliding speed gradually increases with time. In most idling runs, the tangential force coefficient μ remains unchanged or decreases as the sliding speed increases (corresponding to (1) to (6) in the figure). However, when the tangential force coefficient μ at the occurrence of idling is small, the tangential force coefficient μ increases as the sliding speed increases (corresponding to (7) in the figure). For the sake of simplicity, the figure shows only the characteristics for seven idling runs, but in fact, a considerable number of test results are obtained and this tendency is shown. That is, when the tangential force coefficient μ at the occurrence of idling is relatively small, it can be said that by allowing the idling to continue, a greater adhesive force than at the occurrence can be obtained.

  For this reason, in this embodiment, the start timing of re-adhesion control is varied according to the tangential force coefficient μ at the time of occurrence of slipping. That is, when the tangential force coefficient μ is relatively large (specifically, exceeds a predetermined value), the re-adhesion control is immediately activated in the same manner as in the past, and the tangential force coefficient μ is small (specifically, In the case of a predetermined value or less), the re-adhesion control is activated after delaying the timing of re-adhesion control and allowing the idling to continue. Here, the continuation of the idling is allowed only when the tangential force coefficient μ is small. For this reason, the influence of wear on the wheels and rails due to the continuation of idling is small.

FIG. 2 is a diagram for explaining the re-adhesion control of the present embodiment. In the figure, the horizontal axis is time t, the peripheral speed V of the control target axis is shown together with the reference speed (target speed) Vm on the upper side, and the generated torque τ _e of the electric motor driving the target axis is shown on the lower side. Yes. According to the figure, when idling does not occur, the peripheral speed V substantially coincides with the reference speed Vm, and the motor torque τ _e is kept substantially constant. When idling occurs, the circumferential speed V increases, and the speed difference Vd that is the difference from the reference speed Vm increases. When the speed difference Vd reaches a predetermined threshold value Vs1 at time t1, the occurrence of idling is detected. Subsequently, when the speed difference Vd further increases and reaches a predetermined threshold value Vs2 at time t2, the re-adhesion control is activated. However, Vs1 ≦ Vs2.

When the re-adhesion control is activated, the reduction of the motor torque τ _e is started. At this time, the reduction of the motor torque τ _e is performed at a predetermined reduction speed Wt. The reduction in the motor torque τ _e is continued until the increase in the peripheral speed V becomes zero, that is, until the acceleration α obtained by differentiating the peripheral speed V becomes zero. Lowering the motor torque tau _e peripheral speed V is lowered, the speed difference Vd is returning operation of the re-adhesion control is started at time t3 equal to or less than the threshold value Vr determined in advance. That is, control for reducing the reduction amount of the motor torque τ _e and returning the torque is started. Then, at time t4 when the electric motor torque τ _e returns to the value at the start time (time t1) of the re-adhesion control, the re-adhesion control ends. At this time, the motor torque τ _e is controlled so as to return over a predetermined return time Tt.

  In the present embodiment, the threshold value Vs2 for determining the re-adhesion control activation timing and the threshold value Vr for determining the re-adhesion control return timing are varied according to the tangential force coefficient μ at the time when the occurrence of idling is detected. . Specifically, when the tangential force coefficient μ is relatively large (that is, greater than a predetermined value), Vs1 = Vs2, and when the occurrence of idling is detected, the re-adhesion control is activated immediately. On the other hand, when the tangential force coefficient μ is small (that is, equal to or less than a predetermined value), Vs2> Vs1 is set, and the triggering timing of the re-adhesion control is delayed.

  Furthermore, in the present embodiment, the generated torque reduction speed Wt and the return time Tt, which are control parameters for the re-adhesion control (re-adhesion control parameter), are varied according to the tangential force coefficient μ when the occurrence of idling is detected. .

[Constitution]
FIG. 3 is a block diagram showing a schematic configuration of the main circuit of the train in this embodiment, and shows one drive shaft. That is, although control of an electric motor is demonstrated below as individual control (what is called 1C1M), embodiment which can apply this invention is not restricted to this. For example, the present invention can be applied to 1C4M that controls two wheels of a moving wheel for two vehicles collectively. According to the figure, the main circuit of the train includes an electric motor 10, a speed sensor 12, an inverter 20, a current sensor 30, and an electric motor control device 40.

The electric motor 10 is a main electric motor (main motor) that rotates the axle by being supplied with electric power from the inverter 20, and is realized by, for example, a three-phase induction motor. The speed sensor 12 detects the rotational speed (circumferential speed) V of the electric motor 10. The inverter 20 is supplied with overhead power via a pantograph and a converter. Then, the output voltage is adjusted based on the voltage command values Vu ^* , Vv ^* , Vw ^* of the U phase, V phase, and W phase input from the vector arithmetic control device 43, and the electric motor 10 is supplied with power. The current sensor 30 is provided at the input end of the electric motor 10 and detects U-phase and V-phase currents Iu and Iv flowing into the electric motor 10.

  The electric motor control device 40 performs vector control of the electric motor 10. The electric motor control device 40 is realized by a computer or the like including a CPU, a ROM, a RAM, and the like. Configured as The motor control device 40 includes a μ calculation device 41, a re-adhesion control device 42, and a vector calculation control device 43.

  Based on the currents Iv and Iu detected by the current sensor 30 and the peripheral speed V detected by the speed sensor 12, the μ calculation device 41 calculates the tangential force coefficient μ of the wheel to be controlled according to the equation (1). The rotational speed of the axle is not directly detected, but the circumferential speed is estimated by an estimation method used in so-called speed sensorless vector control (for example, a method of estimating the rotational speed based on the armature voltage or armature current of the induction motor). By obtaining V, the speed sensor 12 may be unnecessary.

  The re-adhesion control device 42 controls the torque generated by the motor 10 based on the tangential force coefficient μ calculated by the μ calculation device 41, the peripheral speed V detected by the speed sensor 12, and the input reference speed Vm. A torque reduction command signal for executing the re-adhesion control is generated. Here, the reference speed Vm is the traveling speed of the train, and may be obtained from, for example, a speed signal obtained from the driver's cab or the peripheral speed of the driven shaft of the T car. Alternatively, it may be determined as a minimum value during power running, or as a maximum value during braking.

The vector calculation control device 43 determines the voltage to the inverter 20 based on the current command values Id ^* and Iq ^* input from a current command generation device (not shown ⁾ and the torque reduction command signal input from the re-adhesion control device 42. Command values Vu ^* , Vv ^* , Vw ^* are generated. Specifically, while the torque reduction command signal is not input, the voltage command values Vu ^* , Vv ^* , Vw ^* are calculated based on the current command values Id ^* , Iq ^* , and the torque reduction command signal is input. The voltage command values Vu ^* , Vv ^* , Vw ^* are calculated so as to reduce the torque generated by the electric motor 10 by an amount corresponding to the signal.

  FIG. 4 is a block diagram showing a circuit configuration of the re-adhesion control device 42. According to the figure, the re-adhesion control device 42 includes an adder 421, a differentiator 422, an idling detection unit 423, an activation command unit 424, a return command unit 425, a holding circuit 426, and a parameter switching unit 427. And a re-adhesion controller 428.

  The adder 421 calculates a speed difference Vd by subtracting the input reference speed Vm from the peripheral speed V. The differentiator 422 calculates the acceleration α by differentiating the inputted peripheral speed V.

  The idling detection unit 423 includes comparators 4231 and 4232, an OR gate 4233, and an idling threshold value switch 4234, and detects the occurrence of idling of the moving wheel to be controlled. The comparator 4231 compares and determines whether or not the speed difference Vd input from the adder 421 exceeds a set threshold value Vs1, and outputs a determination signal when it is determined that the speed difference Vd has exceeded. The comparator 4232 compares and determines whether or not the acceleration α input from the differentiator 422 exceeds a set threshold value αs1, and outputs a determination signal when determining that the acceleration α exceeds the threshold αs1.

  The OR gate 4233 calculates the logical sum of the determination signals input from the comparators 4231 and 4232, respectively. The output signal from the OR gate 4233 is the idling detection signal S1. That is, when a determination signal is input from at least one of the comparators 4231 and 4232, the idling detection signal S1 is output. That is, the idling detection unit 423 outputs the idling detection signal S1 when the speed difference Vd exceeds the threshold value Vs1 or when the acceleration α exceeds the threshold value αs1.

  The idling threshold value switching unit 4234 switches threshold values Vs1 and αs1 (hereinafter referred to as “idling detection threshold value”) set in each of the comparators 4231 and 4232 based on the inputted reference speed Vm. Specifically, the current speed range is determined based on the reference speed Vm. Next, an idle detection threshold value corresponding to the determined speed range is set in each of the comparators 4231 and 4232 according to the idle detection threshold value table TBL1.

  FIG. 5 shows an example of the idling detection threshold value table TBL1. According to the figure, the idling detection threshold value table TBL1 sets the value of each idling detection threshold value for each speed range. Here, there are three types of speed ranges: “high speed range”, “medium speed range”, and “low speed range”. It should be noted that the number of speed ranges is not limited to these three types, and may be any number.

  The activation command unit 424 includes a timer 4241, comparators 4242, 4243, and 4244, and an OR gate 4245, and instructs (commands) the re-adhesion control to be activated on the driving wheel to be controlled. The timer 4241 resets the time and starts at the timing when the idling detection signal S1 is input from the idling detection unit 423. That is, the time T measured by the timer 4241 is an elapsed time from the point in time when idling is detected. The comparator 4242 compares and determines whether or not the measured time T of the timer 4241 exceeds a set threshold value Ts, and outputs a determination signal when it is determined that the timer 4241 has exceeded it. The comparator 4243 compares and determines whether or not the speed difference Vd input from the adder 421 exceeds the set threshold value Vs2, and outputs a determination signal when it is determined that the speed difference Vd has exceeded. The comparator 4244 compares and determines whether or not the acceleration α input from the differentiator 422 exceeds a set threshold value α2, and outputs a determination signal when determining that the acceleration α exceeds the threshold α2.

  The OR gate 4245 calculates the logical sum of the determination signals input from the comparators 4242, 4243, and 4244, respectively. The output signal from the OR gate 4245 becomes the activation command signal S2. That is, when a determination signal is input from at least one of the comparators 4242, 4243, and 4244, the activation command signal S2 is output. That is, the activation command unit 424 performs the re-adhesion control when the speed difference Vd exceeds the threshold value Vs2, when the acceleration α exceeds the threshold value αs2, or when the elapsed time since the detection of the idling has reached the threshold value Ts. The activation command signal S2 for instructing the activation (starting) is output. Here, “the velocity difference Vd exceeds the threshold value Vs2 or the acceleration α exceeds the threshold value αs2” is an activation condition of the re-adhesion control. In addition, “the elapsed time from the detection of idling” reaches the threshold value Ts is a condition for forcibly activating the re-adhesion control.

  The return command unit 425 includes comparators 4251 and 4252 and an AND gate 4253, and instructs (commands) a return operation of the activated re-adhesion control. The comparator 4251 compares and determines whether or not the speed difference Vd input from the adder 421 is lower than a set threshold value Vr, and outputs a determination signal when it is determined that the speed difference Vd is lower. The comparator 4252 compares and determines whether or not the acceleration α input from the differentiator 422 is lower than a set threshold value αr, and outputs a determination signal when determining that the acceleration α is lower than the threshold value αr.

  The AND gate 4253 calculates the logical performance of the determination signals input from the comparators 4251 and 4252, respectively. The output signal from the AND gate 4253 becomes the return command signal S3. That is, when the determination signal is input from both the comparators 4251 and 4252, the return command signal S3 is output. That is, the return command unit 425 outputs the return command signal S3 that instructs the return of the generated torque of the electric motor 10 when the acceleration α is less than the threshold value αr and the speed difference Vd is less than the threshold value Vr. Here, “the acceleration α is below the threshold value αr and the speed difference Vd is below the threshold value Vr” is a return condition for starting the return operation of the re-adhesion control.

  The holding circuit 426 holds the input reference speed Vm and the tangential force coefficient μ at the timing when the idling detection signal S1 is inputted from the idling detection unit 423. In other words, the holding circuit 426 holds the reference speed Vm and the tangential force coefficient μ at the time when the latest (current) idling is detected.

  The re-adhesion controller 428 generates torque generated by the electric motor 10 based on the activation command signal S2 input from the activation command unit 424, the return command signal S3 input from the return command unit 425, and the set re-adhesion control parameter. To generate and output a torque command signal for realizing re-adhesion. Specifically, when the activation command signal S2 is input from the activation command unit 424, a torque reduction command signal is generated so as to reduce (decrease) the torque generated by the electric motor 10 at the set torque reduction speed Wt. , Re-adhere the idle wheel to the track. Thereafter, when a return command signal S3 is input from the return command unit 425, a torque reduction command signal is generated so that the reduced generated torque is returned at the set return time Tt.

  The parameter switching unit 427 is based on the reference speed Vm and the tangential force coefficient μ input from the holding circuit 426, and thresholds Ts, Vs2, and αs2 (hereinafter referred to as “thresholds”) set in the comparators 4242, 4243, and 4244 of the activation command unit 424, respectively. , “Activation command threshold”), thresholds αr and Vr (hereinafter referred to as “return command threshold”) set in the comparators 4251 and 4252 of the return command unit 425, and torque set in the re-adhesion controller 428, respectively. The pull-down speed Wt and the return time Tt (hereinafter referred to as “re-adhesion control parameter”) are switched. Specifically, the speed range is determined based on the reference speed Vm. Next, the activation command threshold corresponding to the tangential force coefficient μ is set in each of the comparators 4242, 4243, and 4244 of the activation command unit 424 according to the determined speed range parameter table TBL2, and the return command threshold is set in the return command unit 425. Each of the comparators 4251 and 4252 is set, and the re-adhesion control parameter is set in the re-adhesion controller 428.

  That is, the activation command threshold set for each of the comparators 4242, 4243, and 4244 of the activation command unit 424, the return command threshold set for each of the comparators 4251 and 4252 of the return command unit 425, and the re-adhesion controller 428. The re-adhesion control parameter set to is a value corresponding to the reference speed Vm and the tangential force coefficient μ at the time of detection of the occurrence of the current idling.

FIG. 6 shows an example of the parameter table TBL2. The parameter table TBL2 is prepared for each of three types of speed ranges, “high speed range”, “medium speed range”, and “low speed range”. FIG. 5A shows a parameter table TBL2 for “high speed range”, FIG. 5B shows a parameter table TBL2 for “medium speed range”, and FIG. This is a table TBL2. In the parameter table TBL2, the values of the activation command threshold, the return command threshold, and the re-adhesion control parameter are set for each tangential force coefficient μ. The activation command threshold is a speed difference Vs2 set as a threshold value in the comparator 4243 of the activation command unit 424, an acceleration αs2 set as a threshold value in the comparator 4244, and a forced activation time Ts set as a threshold value in the comparator 4242. is there. The return command threshold is a speed difference Vr set as a threshold value in the comparator 4251 of the return command unit 425 and an acceleration αr set as a threshold value in the comparator 4252. Further, the re-adhesion control parameters are a reduction speed Wt and a return time Tt of the generated torque τ _e of the electric motor 10.

  According to the parameter table TBL2, when the tangential force coefficient μ is 0.1 or more, the forced activation time Ts is set to “0” in any speed range. For this reason, when the idling detection unit 4233 detects the occurrence of idling, the comparator 4242 immediately outputs a determination signal, and the activation command signal S2 is output from the OR gate 4245 to the re-adhesion controller 428. And re-adhesion control is immediately started.

  On the other hand, when the tangential force coefficient μ is less than 0.1, the forced activation time Ts is set to a value larger than 0, and the speed of the idling detection threshold is used as the activation command threshold for the speed difference Vs2 and the acceleration αs2. A value larger than each of the difference Vs1 and the acceleration αs1 is set. As a result, if the value of the tangential force coefficient μ when the occurrence of idling is detected is a relatively small value, re-adhesion control is not started immediately after the occurrence of idling, but idling This is temporarily allowed to continue. An increase in the tangential force coefficient μ can be expected by allowing the idling to continue.

  In addition, the lower the tangential force coefficient μ at the time of idling, the lower the tangential force coefficient μ at the occurrence of idling, the higher the activation command threshold value. Is set to

  In addition, the higher the speed range, the larger the amount of change in the peripheral speed of the wheel and the acceleration per unit time. Therefore, the higher the speed range, the higher the activation command threshold.

  Even if the tangential force coefficient μ is less than 0.1, the continuation of the idling for a certain time or more will cause great wear on the wheels and rails, so the elapsed time from the detection of the occurrence of idling When the forced activation time Ts is reached, the re-adhesion control is forcibly started.

  In the return command, the lower the tangential force coefficient μ, the larger the return command threshold (only the speed difference Vr is set in FIG. 6), and the higher the speed range, the larger the value is set. As the return command threshold value is larger, the effect of starting the torque return operation earlier is obtained (see FIG. 2). For this reason, the torque return operation can be started earlier as the tangential force coefficient μ is lower or the higher the speed range.

Further, the torque reduction speed Wt and the return time Tt are varied depending on whether or not the tangential force coefficient μ is less than 0.1. Specifically, when the tangential force coefficient μ is a value expected to increase due to the continuation of idling (less than 0.1), the torque reduction speed Wt is set to a small value, and the return time Tt is set to a large value. Can be switched.

  The threshold value of the value of the tangential force coefficient μ at the time of detecting the occurrence of the idling that is expected to increase due to the continuation of the idling is assumed to be 0.1. Each value of the parameter table TBL2 of FIG. 5 and the idling detection threshold value table TBL1 of FIG. 5 are also examples. Of course, the design may be changed as appropriate according to the carriage, train, or the like to which this embodiment is applied.

Further, the above-described activation control of the re-adhesion control is executed in the same manner even when idling is again detected and detected during the torque return operation. Concretely, it demonstrates with reference to FIG. 7 which showed the other example of re-adhesion control. FIG. 7 shows that after the return operation of the re-adhesion control is started at time t3 in FIG. 2, the idling is performed again until the motor torque τ _e returns to the value at the start time (time t1) of the re-adhesion control. It is an example when it occurs. When the speed difference Vd reaches a predetermined threshold value Vs1 at time t31, the idling detection unit 423 detects the occurrence of idling again. Subsequently, when the speed difference Vd further increases and reaches the speed difference Vs2 of the activation command threshold at time t32, the activation command unit 424 issues an activation command for re-adhesion control.

  Note that the timer 4241 resets and restarts the time counting by the idling detection signal S1 from the idling detection unit 423 at time t31.

[Modification]
It should be noted that the application of the present invention is not limited to the above-described embodiment, and can of course be changed as appropriate without departing from the spirit of the present invention.

(A) Parameter switching timing For example, in the above-described embodiment, the activation command threshold value, the return command threshold value, and the re-adhesion control parameter are switched according to the tangential force coefficient μ at the timing at the detection timing of the occurrence of idling. However, this may be switched as needed.

  A re-adhesion control device 42A as an example of the re-adhesion control device 42 in this case is shown in FIG. However, in the figure, the same reference numerals are given to the same components as the re-adhesion control device 42 in FIG. According to FIG. 8, the re-adhesion control device 42 </ b> A removes the holding circuit 426 in the re-adhesion control device 42 shown in FIG. 4, and the activation command holding unit 4246 in the activation command unit 424 and the return command in the return command unit 425. A holding unit 4254 and a reset signal generator 429 are further provided.

  The parameter switching unit 427 switches the activation command threshold value, the return command threshold value, and the re-adhesion control parameter according to the parameter table TBL2 shown in FIG. 6, for example, based on the input reference speed Vm and the tangential force coefficient μ as needed. .

  The activation command holding unit 4246 holds the output signal of the OR gate 4245 and outputs the held signal. That is, when the determination signal is output from at least one of the comparators 4242, 4243, and 4244 by the OR gate 4245 to the activation command holding unit 4246, an ON signal is input. Then, even if it is no longer input, the input ON signal is kept and output. When the reset signal is input from the reset signal generator 429, the held signal is reset. The output signal from the activation command holding unit 4246 becomes the activation command signal S2 output from the activation command unit 424.

  The return command holding unit 4254 holds the output signal of the AND gate 4253 and outputs the held signal. That is, when the determination signal is output from both of the comparators 4251 and 4252 by the AND gate 4253, the ON signal is input to the return command holding unit 4254. However, once this ON signal is input, it is input. Even if it disappears, it keeps holding the input ON signal. When the reset signal is input from the reset signal generator 429, the held signal is reset. The output signal from the return command holding unit 4254 becomes the return command signal S3 output from the return command unit 425.

  The reset signal generator 429 generates and outputs a reset signal based on the torque reduction command signal input from the re-adhesion controller 428. Specifically, the reset signal is generated and output at the time when the re-adhesion control ends, that is, with a command signal indicating that the torque reduction amount is zero (the state at time t4, which is the end time of the re-adhesion control in FIG. 2). To do.

(B) Detection frequency of idling and sliding In the above-described embodiment, each time the occurrence of idling is detected, the parameter is switched according to the tangential force coefficient μ at the time of detection. It may be switched according to the detection frequency of the occurrence of the occurrence of.

  FIG. 9 shows a circuit configuration of a re-adhesion control device 42B which is an example of the re-adhesion control device 42 in this case. However, in the figure, the same reference numerals are given to the same components as the re-adhesion control device 42 in FIG. According to FIG. 9, the re-adhesion control device 42 </ b> B is configured to further include a high-frequency occurrence detector 431 in the re-adhesion control device 42 shown in FIG. 4.

  The high-frequency occurrence detector 431 detects whether the occurrence frequency of the idling is high based on the idling detection signal S1 input from the idling detection unit 423. Specifically, the input frequency of the idling detection signal S1 from the idling detection unit 423 (the number of times the idling detection signal S1 is input with respect to the past predetermined time) is calculated. This input frequency corresponds to the occurrence frequency of idling. Next, when the calculated input frequency exceeds a predetermined threshold, it is determined that the occurrence frequency is high, and when it is equal to or less than the threshold, it is determined that the frequency is not high (that is, low frequency). Then, the determination result of whether or not the frequency is high is output as a detection result signal. The high-frequency occurrence detector 431 determines whether or not the frequency is high and outputs a determination result signal at a predetermined period.

  Based on the detection result signal input from the high-frequency occurrence detector 431, the parameter switching unit 427 includes an activation command threshold set in the activation command unit 424 and a return command threshold set in the return command unit 425 according to the parameter table TBL3. Each of the re-adhesion control parameters set in the re-adhesion controller 428 is switched.

  FIG. 10 shows an example of the parameter table TBL3. According to the figure, the parameter table TBL3 is prepared for each of three types of speed ranges of “high speed range”, “medium speed range”, and “low speed range”. In the figure, the parameter table TBL3 for “high speed range” is shown, but the other “medium speed range” and “low speed range” have the same configuration. In the parameter table TBL3, the values of the activation command threshold, the return command threshold, and the re-adhesion control parameter are set for each of the high-frequency detection results of “with detection” and “without detection”. For the high-frequency detection result “detected”, the value of each parameter is set for each tangential force coefficient μ.

(C) Mode of motor control In the above-described embodiment, one motor control device 40 controls one motor 10 so-called 1C1M. However, other control methods, for example, one motor control device uses four motor control devices. Even in the case of 1C4M for controlling an electric motor, the same applies.

(D) Tangential force coefficient equivalent value In the above-described embodiment, the tangential force coefficient μ itself is used as an example of the tangential force coefficient equivalent value. However, the tangential force, the adhesive force, the current value of the motor (for example, torque current), etc. Any value may be used as long as it is a value that exhibits the same variation as the variation of the tangential force coefficient (a value that is almost linear with the tangential force coefficient) and that can be handled equivalently or substantially equivalently to the tangential force coefficient μ.

(E) Variable control of activation command threshold based on rate of change of tangential force coefficient μ during idling and sliding In the above embodiment, activation command threshold based on the value of tangential force coefficient μ when occurrence of idling is detected The return command threshold value and the return command threshold value etc. are fixed based on the change (rate of change) per unit time of the tangential force coefficient μ during idling. It is good to do. Specifically, the activation command threshold value, the return command threshold value, and the like are once determined based on the value of the tangential force coefficient μ when the occurrence of idling is detected. Thereafter, the tangential force coefficient μ is determined at predetermined time intervals (for example, 10 msec intervals). The change rate (time derivative) of is calculated, and the previously determined activation command threshold, return command threshold, etc. are varied in real time according to the calculated change rate of the tangential force coefficient μ.

(F) Electric vehicle Furthermore, in the above-mentioned embodiment, although the train which is a kind of electric vehicle was demonstrated, it is applicable similarly to an electric vehicle etc., for example.

An example of a test result. Explanatory drawing of re-adhesion control. The main circuit block diagram of a train. The circuit block diagram of a re-adhesion control apparatus. An example of an idling detection threshold value table. An example of a parameter table. Explanatory drawing of re-adhesion control. The modification of a re-adhesion control apparatus. The modification of a re-adhesion control apparatus. An example of the parameter table in the re-adhesion control apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Main motor 40 Electric motor control apparatus 41 (micro | micron | mu) calculation apparatus 42 Re-adhesion control apparatus 423 Idling detection part 4231, 4232 Comparator, 4233 Idling threshold value switcher, 4234 OR gate 424 Activation command part 4241 Timer, 4242, 4243, 4244 Comparator, 4245 OR gate 425 Return command unit 4251, 4252 Comparator, 4253 AND gate 426 Holding circuit, 427 Parameter switcher, 428 Re-adhesion controller 43 Vector arithmetic control device S1 Sliding detection signal, S2 Start command signal, S3 Return command signal

Claims (15)

An electric motor control device that controls an electric motor that drives a driving wheel of an electric vehicle, detects occurrence of idling of the driving wheel, and performs re-adhesion control of the driving wheel,
Tangential force coefficient equivalent value detection means for detecting a tangential force coefficient equivalent value of the driving wheel;
1) a first speed difference reference condition that uses the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values; and / or 2) a first periphery that uses the peripheral acceleration of the moving wheel as a determination target value. An activation condition matching detection means for detecting that the activation condition of the re-adhesion control including at least an acceleration reference condition is satisfied;
Re-adhesion control activating means for activating the re-adhesion control in response to detection by the activation condition match detection means;
With
An electric motor control device further comprising an activation condition varying means for varying the activation condition based on a tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. Further comprising an idling detection means for detecting the occurrence of idling of the driving wheel,
2. The activation condition varying means varies the activation condition based on a tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means when detection by the idling / sliding detection means is performed. The motor control device described. Idle running detection means for detecting occurrence of idle running of the driving wheel;
There is a possibility that the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detecting means when the occurrence of idling of the driving wheel is detected by the idle running detection means will increase when the idle running is continued. An idle running occurrence immediate activation means that activates the re-adhesion control in response to the detection of the idle sliding detection means when it is not within a predetermined allowable continuous range as a certain value range;
The motor control device according to claim 1, further comprising: A non-activation detecting means for detecting that the re-adhesion control is not activated by the re-adhesion control activating means until a predetermined time has elapsed since the detection by the idling sliding detection means;
Forced activation means for forcibly activating the re-adhesion control in response to detection by the non-activation detection means;
The motor control device according to claim 2 or 3, further comprising:   The activation condition varying means includes a continuation allowable range that is determined in advance as a range of values that may increase when the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means continues idling. The motor control device according to any one of claims 1 to 4, wherein the activation condition is changed to a condition content that allows the idling to be continued when compared with a case where the activation condition is not within the allowable continuous range. . Idle running detection means for detecting occurrence of idle running of the driving wheel;
An idle running high frequency occurrence detecting means for detecting that the detection frequency by the idle running detection means matches a predetermined high frequency condition;
Further comprising
The activation condition varying means varies the activation condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means when the idle running high frequency occurrence detection means is detected. The electric motor control device according to claim 1. The activation condition includes at least the first speed difference reference condition,
In the first speed difference reference condition, a speed difference between a peripheral speed of the driving wheel and a traveling speed of the electric vehicle or a threshold of a slip ratio is defined as a condition.
The motor control device according to any one of claims 1 to 6, wherein the activation condition varying unit varies the activation condition by increasing or decreasing the threshold value.   The motor control device according to claim 7, wherein the activation condition variable unit increases the threshold value as the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection unit decreases. The activation condition includes at least the first circumferential acceleration reference condition,
In the first circumferential acceleration reference condition, a threshold value of the circumferential acceleration of the driving wheel is defined as a condition,
The motor control device according to any one of claims 1 to 8, wherein the activation condition varying unit varies the activation condition by increasing or decreasing a threshold value of the circumferential acceleration.   The motor control device according to claim 9, wherein the activation condition variable unit increases the threshold value of the circumferential acceleration as the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection unit decreases.   The motor control device according to any one of claims 1 to 10, wherein the activation condition varying unit further varies the activation condition based on a traveling speed of the electric vehicle. A) a second speed difference reference condition that uses the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values; and / or b) a second periphery that uses the peripheral acceleration of the driving wheel as a determination target value. A return condition matching detection means for detecting that a return condition for starting a return operation of the re-adhesion control activated by the re-adhesion control activating means, including at least an acceleration reference condition;
Re-adhesion control return means for starting a return operation of re-adhesion control activated by the re-adhesion control activation means in response to detection by the return condition match detection means;
Return condition variable means for changing the return condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means;
The electric motor control device according to claim 1, further comprising:   The torque reduction speed varying means for varying the torque reduction speed, which is a control parameter for the re-adhesion control, based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. The electric motor control device according to any one of the above.   The return time variable means which changes the return time which is a control parameter of the re-adhesion control based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection means. The electric motor control device according to one item. A re-adhesion control method for detecting occurrence of idling of the moving wheel and performing re-adhesion control of the moving wheel when controlling an electric motor that drives a driving wheel of an electric vehicle,
A tangential force coefficient equivalent value detecting step for detecting a tangential force coefficient equivalent value of the driving wheel;
1) a first speed difference reference condition that uses the peripheral speed of the moving wheel and the traveling speed of the electric vehicle as determination target values; and / or 2) a first periphery that uses the peripheral acceleration of the moving wheel as a determination target value. An activation condition match detection step for detecting that the activation condition of the re-adhesion control including at least an acceleration reference condition is satisfied;
A re-adhesion control activation step for activating the re-adhesion control in response to detection by the activation condition match detection step;
Including
The re-adhesion control method further comprising an activation condition variable step of varying the activation condition based on the tangential force coefficient equivalent value detected by the tangential force coefficient equivalent value detection step.

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