JPH0832122B2 - Electric car control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to an electric vehicle controller.

(Prior Art) The use of an induction motor as a main motor of a railway vehicle has great advantages in terms of downsizing and weight saving and maintenance-free. By the way, in order to control the speed of an induction motor efficiently, variable voltage / variable frequency control (hereinafter VVVF
VV that uses a thyristor, etc.
VF inverter is used.

Fig. 7 shows the relationship between the equivalent circuit for one phase of the induction motor and the VVVF inverter and the input filter. 20 is the input filter reactor L ₀ , 21 is the input filter capacitor C ₀ , 22 is the VVVF inverter, 23 Is the primary leakage inductance L ₁ , 24 is the primary range stance R ₁ , 25 is the excitation inductance Lm, 26 is the secondary leakage inductance L ₂ , and 27 is the equivalent secondary resistance R ₂ / S ₁ .

Here, S ₁ is the slip of the induction motor and is defined as follows.

S ₁ = Slip frequency FS / Inverter output frequency F This VVVF system requires complicated control and PMW modulation must be performed to reduce power source harmonics, so advanced control technology is required. To be done.

Conventionally, as a control unit of such a PMW modulation VVVF inverter, the method shown in FIG. 8 has been taken. FIG. 8 is a block diagram showing a control unit of a conventional VVVF inverter. 1 is a pulse generator that generates a pulse corresponding to the rotation speed FR of the induction motor, and 2 is a rotation frequency FR from the signal of the pulse generator 1. Rotation speed frequency calculation unit 3 for calculating the slip frequency detection unit for detecting wheel slip and slip from the signal change rate of the pulse generator 1 4 for master controller command M and notch command P / B Valves 5 are master controller commands (hereinafter simply referred to as masscon commands) MC
And the current command value calculation unit that calculates the current command value IC according to the variable load VL and the slipping condition WSD, 6 is the notch command P /
This is a power running regeneration determination unit that determines whether the power running P state or the regenerative B state is performed by B, and outputs a power running P and regeneration B determination signal based on the determination result. 7 is the current command value IC
And a slip frequency calculation unit for calculating the reference slip frequency FS according to the current deviation IU between the current command value IC and the current IM of the induction motor, and 8 is the inverter frequency F and the input voltage of the VVVF inverter (that is, the seventh Capacitor in figure
C ₀ terminal voltage) EC and a modulation factor calculation unit that calculates the modulation factor AL from the conditions of power running P or regeneration B, 9 is a modulation pulse mode calculation unit that calculates the modulation pulse mode N from the inverter frequency F, and 10 is an inverter frequency This is a PWM modulation unit that performs PWM modulation (pulse width modulation) according to F, modulation pulse mode N, and modulation rate AL.

Further, FIG. 9 shows the slip frequency calculator 7 shown in FIG.
It is a figure showing the details of. As shown in the figure, the slip frequency calculation unit 7 is a reference slip frequency FS1 for the current command value IC.
Of the current command value IC from the current command value calculator 5 and the function unit 11 that outputs the reference slip frequency FS1 to the current command value IC and the first-order delay compensation of the current deviation IU to determine the compensated output. Output as current compensation slip frequency FS2 1
A second delay compensator 12 is provided, and the sum of the reference slip frequency FS1 and the constant current compensating slip frequency FS2, which are these outputs, is passed through a limiter 13 and then output as the slip frequency FS. As a result, ICIM control can be performed.

In the VVVF inverter having such a control unit, the pulse generator 1 detects the rotation speed of the electric motor. Then, the rotation frequency calculator 2 calculates the rotation frequency FR of the induction motor from the signal of the pulse generator 1 and outputs it.

On the other hand, the slipping detection section 3 detects slipping and slipping of a wheel based on the signal change rate of the pulse generator 1. And
This is output as the slipping condition WSD.

The master controller and the brake valve 4 output a mass control command MC and a notch command P / B, which are given to the current command value calculation unit 5 and the power running regeneration determination unit 6. The current command value calculation unit 5 calculates the current command value IC according to the mass control command MC, the idling sliding condition WSD, and the variable load VL given from the outside, and outputs the calculated current command value IC to the slip frequency calculation unit 7. . Further, the power running regeneration determining unit 6 determines whether the power running P state or the regenerative B state is in accordance with the notch command P / B. Then, the discrimination result is given to the modulation factor calculation unit 8. The slip frequency calculator 7 calculates the reference slip frequency FS according to the current command value IC and the current deviation IU between the current IM of the induction motor and the current command value IC. Then, the calculated slip frequency FS is added to the rotation frequency FR calculated by the rotation frequency calculation unit 2 to obtain the inverter frequency F.
Becomes The modulation factor calculator 8 calculates the modulation factor AL from the inverter frequency F and the inverter input voltage EC according to the power running P and regeneration B conditions. Further, the modulation pulse mode calculator 9 calculates the modulation pulse mode N from the inverter frequency F. The inverter frequency F, the modulation pulse mode N, and the modulation rate AL thus obtained are given to the PWM modulation section 10, and the PWM modulation section 10 performs PWM modulation according to the inverter frequency F, the modulation pulse mode N, and the modulation rate AL, and the inverter Generates a gate pulse of and supplies it to the inverter section. As a result, the VVVF inverter 22 controls the frequency and voltage under the condition that the current is constant.

When controlling an induction motor with such a VVVF inverter 22, as can be seen from the equivalent circuit shown in FIG. 7, the input filter circuit composed of the input filter reactor L ₀ and the input filter capacitor C ₀ , and the excitation motor side excitation Since there is the inductance Lm, an oscillating current (hunting current) is likely to occur because a current tends to flow between them. The only damping elements that suppress this oscillating current are the primary resistance R ₁ in series and the equivalent secondary resistance R ₂ / S ₁ in parallel. as primary resistance R ₁ is larger, and as the equivalent secondary resistance R ₂ / S ₁ is small,
Great damping effect.

However, the primary resistance R ₁ has a very small value, and conversely, the equivalent secondary resistance R ₂ / S ₁ originally has a small value of the slip S ₁ , and in particular, as the inverter frequency F becomes higher, S _{Since 1} becomes even smaller, it is not possible to expect a large damping effect with this alone.

(Problems to be Solved by the Invention) As described above, when the induction motor is controlled by the VVVF inverter, as can be seen from the equivalent circuit shown in FIG. 7, the input filter reactor L ₀ and the input filter capacitor C ₀ are used. Since there is the configured input filter circuit and the excitation inductance Lm on the induction motor side, a current tends to flow between them. Therefore, an oscillating current is likely to occur, but the only damping element for this oscillating current is the primary resistance R ₁ in series and the equivalent secondary resistance R ₂ / S _{1 in} parallel. is there. And, in principle, the larger the primary resistance R ₁ is, the more the equivalent 2
The smaller the next resistance R ₂ / S ₁ , the greater the damping effect. However, the primary resistance R ₁ has a very small value, and conversely, the equivalent secondary resistance R ₂ / S ₁ originally has a small value of S ₁ , and in particular, as the inverter frequency F becomes higher, S ₁ becomes Because there is a situation that it will be smaller,
Both cannot be expected to have a large damping effect.

Therefore, as shown in FIGS. 8 and 9, if VVVF control is performed while simply performing constant current control by the slip frequency FS, if oscillating current occurs in the main circuit, set it. There is a drawback that I can not do it.

Therefore, an object of the present invention is to suppress the oscillation phenomenon of the main circuit current that occurs when the induction motor is driven by a VVVF inverter having an input LC filter by slip frequency control without impairing the constant current control performance. An object of the present invention is to provide an electric vehicle control device capable of doing the above.

[Structure of Invention]

(Means for Solving Problems) That is, in order to achieve the above object, the present invention provides a variable voltage variable frequency inverter in which a filter circuit including a reactor and a capacitor is connected to an input side and an induction motor is connected to an output side. A rotation frequency calculation means for calculating the rotation frequency of the induction motor, a current command value for the induction motor, and a slip frequency calculation based on the deviation between the current command value and the actual current of the induction motor. Frequency calculation means, compensation gain setting means for setting the magnitude of the compensation gain according to the rotation frequency calculated by the rotation frequency calculation means, and the compensation gain for the input voltage to the variable voltage variable frequency inverter. The differential compensation calculation is performed by the compensation gain set by the setting means to obtain the differential compensation value, and the differential compensation value is obtained. Compensation means for adding / subtracting a value to / from the slip frequency, an inverter frequency is calculated from the output of the compensation means and the rotation frequency calculated by the rotation frequency calculation means, and the variable voltage variable frequency inverter is calculated based on the inverter frequency. And a control means for controlling.

(Operation) In such a configuration, in detecting the rotation speed of the induction motor and adding / subtracting a predetermined slip frequency to control the inverter frequency, a predetermined compensation gain and slip are applied to the voltage or current fluctuation of the capacitor. It is obtained as a multiplied differential compensation value, which is added to the slip frequency during power running and subtracted from the slip frequency during regeneration. Further, the compensation gain is changed according to the rotation speed of the induction motor. With this configuration, the oscillation of the main circuit current caused by the voltage fluctuation of the filter capacitor is compensated by the differential compensation value added to the inverter frequency, so that the main circuit current oscillation is suppressed and the constant current control performance is improved. There is no loss.

As described above, according to the present invention, the oscillation phenomenon of the main circuit current generated when the induction motor is driven by the VVVF inverter having the input LC filter by the slip frequency control is easily suppressed without impairing the constant current control performance. You will be able to do it.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a configuration example of a control unit of a VVVF inverter in this system, which is basically the same as the conventional example described in FIG. Therefore, the same parts as those in FIG. 8 are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 1, a part different from FIG. 8 is a slip frequency calculator 17. That is, in the present invention, the induction motor is
It is intended to prevent the oscillating current of the main circuit when controlling the slip frequency with a VF inverter by adding a correction to the slip frequency according to the operating conditions. Therefore, the slip frequency calculation unit 17 does not simply determine the slip frequency to be given from the current command value IC and the deviation of the current IM of the induction motor with respect to the current command value IC unlike the conventional slip frequency calculation unit 7, and The condition of whether the vehicle is in the power running P state or the regenerative state B, the inverter input voltage EC, and the rotation frequency FR obtained by the rotation frequency calculation unit 2
Is taken into consideration.

Therefore, in this device, as shown in FIG. 1, the slip frequency calculation unit 17 has a current command value IC which is the output of the current command value calculation unit 5 and a deviation IU of the current IM of the induction motor with respect to the current command value IC. And the power running P output from the power running regeneration determining unit 6.
The determination result of whether the state is the state of B or the state of regeneration B, the inverter input voltage EC and the rotation frequency FR of the rotation frequency calculation unit 2 to be output are input, and the slip frequency to be given is obtained from these.

FIG. 2 is a block diagram showing details of the slip frequency calculation unit 17 in FIG. As shown in the figure, the slip frequency calculation unit 17 determines the reference slip frequency FS1 for the current command value IC.
Of the current command value IC from the current command value calculator 5 and the function unit 11 that outputs the reference slip frequency FS1 to the current command value IC and the first-order delay compensation of the current deviation IU to determine the compensated output. Output as current compensation slip frequency FS2 1
A differential compensator 14 having a second delay compensator 12 for differentially compensating the inverter input voltage EC, and an output FS3 of the differential compensator 14 as it is or as a polarity reversal device according to the discrimination result of the power regeneration regeneration discrimination unit 6. A switch 15 is provided for switching the polarity of the signal via 16 and outputting the signal. Furthermore, these outputs are the reference slip frequency FS1, the constant current compensation slip frequency FS2, and the output of the differential compensator 14 whose polarity is selected by the switch 15.
The sum of FS3 is passed through the limiter 13 and then output as the slip frequency FS.

Further, FIG. 3 shows the details of the differential compensator 14 in FIG. 2, in which a switch for gain selection is output by the output of the comparison unit 20 which compares the rotational frequency FR with a predetermined reference value C1. 21 is switched to change the differential gain K2. A plurality of differential gains K2, such as K21 and K22, are prepared in advance, and selected from these in accordance with the comparison result. And EC
Is compensated for by the differential gain K2 by the compensation calculation unit 22 to obtain FS3.

In the VVVF inverter having such a control unit, the pulse generator 1 detects the rotation speed of the electric motor. Then, the rotation frequency calculator 2 calculates the rotation frequency FR of the induction motor from the signal of the pulse generator 1 and outputs it. On the other hand, the slipping detection section 3 detects slipping and slipping of a wheel based on the signal change rate of the pulse generator 1. Then, this is output as the slipping condition WSD.

The master controller and the brake valve 4 output a mass control command MC and a notch command P / B, which are given to the current command value calculation unit 5 and the power running regeneration determination unit 6. The current command value calculation unit 5 calculates the current command value IC according to the mass control command MC, the idling sliding condition WSD, and the variable load VL given from the outside, and outputs the calculated current command value IC to the slip frequency calculation unit 17. . Further, the power running regeneration determining unit 6 determines whether the power running P state or the regenerative B state is in accordance with the notch command P / B. Then, the determination result is given to the slip frequency calculating section 17 and the modulation rate calculating section 8. Then, the slip frequency calculation unit 17 determines the rotation frequency FR output by the rotation frequency calculation unit 2, the condition of the current command value IC and the power running P or the regenerative B, and the current command value IC and the current IM of the induction motor. The reference slip frequency FS is calculated according to the deviation IU. That is, the slip frequency calculator 17 has the relationship of the reference slip frequency FS1 with respect to the current command value IC as a function, and the current command value calculator 5 with the function unit 11 that outputs the reference slip frequency FS1 with respect to the input current command value IC. The reference slip frequency FS1 for the current command value IC from is obtained, and the first order delay compensator 12 which performs the first order delay compensation of the current deviation IU and outputs the compensated output as the constant current compensation slip frequency FS2 The constant current compensation slip frequency FS2, which is the primary delay compensation of the deviation IU, is obtained, and the inverter input voltage E
For C, a predetermined differential compensation gain K according to the rotation frequency FR
The differential compensator 14 which performs differential compensation for 2 minutes obtains the differentially compensated output FS3 of the inverter input voltage EC. In addition, the differentially compensated output FS3 is taken out as it is or after inverting the polarity according to the discrimination result of the power running regeneration discriminating unit 6, and further, the reference slip frequency FS1 and the constant current compensation slip frequency FS2 and the differential selected by the switch 15 for the polarity. The sum of the output FS3 of the compensator 14 is passed through the limiter 13 and then output as the slip frequency FS. As a result, the slip frequency with constant current compensation slip frequency and differential compensation of input voltage EC added to the reference slip frequency
FS will be obtained. Then, the slip frequency FS thus calculated is added to the rotation frequency FR calculated by the rotation frequency calculation unit 2 to become the inverter frequency F.
The modulation factor calculator 8 calculates the modulation factor AL from the inverter frequency F and the inverter input voltage EC according to the power running P and regeneration B conditions. Further, the modulation pulse mode calculator 9 calculates the modulation pulse mode N from the inverter frequency F. The inverter output frequency F, the modulation pulse mode N and the modulation rate AL thus obtained are given to the PWM modulation section 10, and the PWM modulation section 10 performs PWM modulation according to the inverter frequency F, the modulation pulse mode N and the modulation rate AL, The gate pulse of the inverter is generated and given to the inverter unit. As a result, the VVVF inverter 22 controls the frequency and voltage under the condition that the current is constant.

With such a configuration, the VVVF inverter 22 can control the AC output voltage EM and the slip frequency FS independently, and, as shown in the control characteristic factor diagram of FIG. Can be controlled.

That is, the output frequency F shown in FIG. 10 in which the AC output voltage EM of the VVVF inverter is proportional to the output frequency F
In the range of the point F ₁ where the AC output voltage is saturated from 0, the AC output voltage EM and the slip frequency FS are both controllable,
Therefore, in this case, the current command value IC and the current IM of the induction motor
Are controlled so that the output frequency F of the VVVF inverter exceeds the above-mentioned F ₁ and the slip frequency of the induction motor is controlled, the VVVF inverter output frequency corresponding to the maximum slip frequency FS at which the slip frequency can be controlled. In the range up to F ₂ , the AC output voltage EM is maximized, and
The slip frequency FS is controlled to increase as it goes from F ₁ to F ₂ , and the current command value IC and the current IM of the induction motor are controlled to be equal to each other as described above.

Further, in the range where the VVVF inverter output frequency F exceeds the above F ₂ , the AC output voltage EM and the slip frequency FS are both controlled to have a maximum maximum value, and the current IM of the induction motor is controlled to be less than the current command value IC.

An object of the present invention is to enhance damping of vibration phenomenon. In the VVVF inverter, the method usually considered as a method for strengthening the damping of the vibration phenomenon is that the differential element of the current IM of the induction motor is negatively fed back to the AC output voltage of the VVVF inverter as is done in general converters. This is a method of adding to the modulation factor AL which is a control parameter of EM. This method is a method for apparently increasing the transient R ₁ only for the oscillating current in FIG. 7, and is not limited to the control converter for varying the voltage, that is, the VVVF inverter, but the chopper device, the phase control rectifier, the CVCF inverter. It is an effective method that is common to all. But this method
As shown in FIG. 10, the VVVF inverter can be applied only when the output frequency F of the VVVF inverter is in the range of 0 to F ₁ , so that the anti-hunt effect is naturally lost in a region outside this range.

In the present invention, attention is paid to the slip frequency FS, which is a control element peculiar to the VVVF inverter, and anti-hunt is enabled by changing and controlling the parallel resonance condition. Specifically, the following actions are performed.

That is, as described with reference to FIG. 7, the equivalent quadratic resistance which is another element for strengthening the damping.
It suffices if R ₂ / S ₁ can be made transiently small only with respect to the oscillating current, but the steady value of the slip frequency FS is set to make the current command value IC and the current IM of the induction motor equal. Reference slip frequency FS1 according to the current command value IC shown in Fig. 9
And current deviation IU constant current compensation slip frequency for first-order lag compensation
It is determined by the constant current control element that is the sum of FS2, so if you add an element that adjusts the slip frequency FS only for the oscillating current that is superimposed on the current IM of the induction motor, that is, the change in the current IM of the induction motor. It will be good.

Therefore, in the present invention, ΔIM is detected by the following method. ΔIM and input filter capacitor voltage oscillation component ΔEC
There is a relationship of

In addition, the DC component of the input filter capacitor voltage is EC ₀
Then, the input filter capacitor voltage EC is EC = EC ₀ + ΔEC. Therefore, the oscillating current component ΔIM can be obtained by differentiating the inverter input voltage EC. (Of course, the oscillating current component ΔIM is measured by directly measuring the current without using the voltage.
May be obtained. Therefore, in order to realize the damping enhancement by the slip frequency, the slip frequency calculation unit 17 shown in FIG. 2 may be made to function.

That is, as described above, the function of the slip frequency calculation unit 17 is to perform differential compensation on the inverter input voltage EC (that is, the voltage of the filter capacitor C ₀ ) by the differential gain K2 to obtain the differential compensation value for the current oscillation. When powering, the switch 15 adds the reference slip frequency FS1 and the constant current compensation slip frequency FS2 to the sum. As a result, when the voltage EC of the filter capacitor is increased, R ₂ /
S ₁ becomes smaller and the excitation inductance Lm shown in Fig. 7
It will act so that the current flowing into will not increase. Conversely, if the filter capacitor voltage EC is to decrease, R ₂ / S ₁ is increased, the current flowing into the exciting inductance Lm acts so as not to decrease. This action tries to keep the current of the exciting inductance Lm constant even if an oscillating current is generated in the current IM of the induction motor, that is, it absorbs the oscillating current by the transient change of the equivalent secondary resistance. Therefore, the fact that the current command value IC and the current IM of the induction motor are equal and have constant current characteristics does not have any influence, and a large damping acts only on the oscillating current.

In the case of power running, since power is supplied from the power supply side,
The fluctuation of the current IM of the induction motor and the voltage EC of the input filter capacitor C ₀ provided on the input side of the inverter have opposite phases. Therefore, when the voltage EC of the input filter capacitor C ₀ is about to rise, by reducing R ₂ / S ₁ , the differential element of the filter capacitor voltage EC is added by positive feedback to suppress the rise, but power regeneration is performed. In the case of a brake, on the contrary, electric power is regenerated to the power supply, so that the fluctuation of the current IM of the induction motor and the fluctuation of the voltage EC of the input filter capacitor C ₀ have the same phase. Therefore, the FS3 output whose polarity is inverted by the switch 15 through the polarity converter 16 is selected and added, that is, the differential element of the voltage EC of the input filter capacitor C ₀ is added by negative feedback, and the same damping effect as in the case of power running is obtained. Will be obtained.

By the way, as described with reference to FIG. 7, when the inverter frequency F becomes higher, the slip S ₁ becomes smaller, so that the damping effect is lowered. To compensate for this, the differential compensator 14
Then, as shown in FIG. 3, the rotation frequency FR is discriminated by the comparison unit 20, and when it is lower than C1, the differential gain K ₂ = K ₂₁ value is set, and when the reference value is C1 or higher, the differential gain K ₂ = K ₂₂ is set. As described above, the level of the differential gain is selectively switched by the switch 21 according to the vehicle speed. Then, by this, the magnitude of the damping effect in the entire speed range is corrected.

In this way, in this device, the oscillating current of the main circuit when controlling the slip frequency of the induction motor with the VVVF inverter is
The equivalent quadratic resistance R ₂ / S ₁ is controlled by adding a differential element to the slip frequency to be applied with the polarity according to the operating conditions to correct it, and this equivalent quadratic resistance R ₂ /
Since so as to suppress and absorb vibration current by transients S _1, the oscillation phenomenon of the main circuit current that occurs when driven by frequency control slip VVVF inverter having an input LC filter an induction motor, a constant current The control performance can be suppressed without any loss.

The present apparatus can also be configured as shown in FIG.
FIG. 4 shows the control unit of the VVVF inverter. Here, the modulation pulse mode N output from the modulation pulse mode calculation unit 9 is given as an input to the slip frequency calculation unit 17a instead of the rotation frequency FR in the system of FIG. It is the one. Further, in this case, the configuration of the slip frequency calculation unit 17 is the fifth.
As shown in the figure, the input of the differential compensator 14a is the inverter input voltage E
Basically, there is no difference from the case of FIG. 2 except that C and modulated pulse mode N are set. The structure of the differential compensator 14a is as shown in FIG. That is, the differential compensator 14a determines, as shown in FIG. 6, whether the output voltage fixing mode (single pulse mode) or not, and the differential of the differential compensator 14a with respect to the voltage EC according to the comparison result. Gain changing switch 31 for selecting gain K2 (selecting which one of preset gains K23 and K24 of different levels is set), differential compensation gain K2 selected by this gain changing switch 31
Compensated output for EC fluctuations by differentially compensating for the voltage EC, and output as FS3
Consists of 2.

In the VVVF control characteristics in Fig. 10, output frequency F1
The following is the inverter output voltage variable control area, and
The output voltage is fixed above F1.

This control mode is determined by the modulation pulse mode operation unit 9 in FIG. 4 which constitutes the control unit, and is discriminated using the output modulation pulse mode signal N. Therefore, the modulated pulse mode signal N is input to the differential compensator 14a of the slip frequency computing unit 17a in FIG. 4, and the differential compensator 14a outputs the output voltage fixed mode in the comparing unit 30 as shown in FIG. Determine whether it is single pulse mode,
The gain selector switch 31 is switched according to the result of this determination, and the optimum gain is selected and given to the compensation calculation unit 32. That is, in the configuration of FIG. 4, the differential compensator 14 with respect to the voltage EC
The differential gain K2 of a is changed according to the mode discrimination result,
The compensation calculation unit 32 corrects the damping effect in the entire speed range by correcting the voltage EC by the amount corresponding to the selected differential gain K2 and performing differential compensation.

This also has an induction motor with an input LC filter
It is possible to prevent the vibration phenomenon of the main circuit that occurs when the VVVF inverter is driven by slip frequency control without any loss of constant current control performance.

〔The invention's effect〕

As described above in detail, according to the present invention, in an electric vehicle using a VVVF inverter having an LC filter on the input side as a power source, an electric vehicle capable of easily suppressing the vibration phenomenon of the main circuit current. A control device can be provided.

[Brief description of drawings]

FIG. 1 is a control block diagram showing an embodiment of the present invention, and FIG.
FIG. 3 is a block diagram showing a configuration example of a slip frequency computing unit used in the present apparatus, FIG. 3 is a block diagram showing a configuration of a differential compensator thereof, and FIG. 4 is a block diagram showing another embodiment of a control unit. FIG. 5 is a block diagram showing a configuration example of the slip frequency calculating section, FIG. 6 is a block diagram showing a configuration of the differential compensator in FIG. 5, and FIG. 7 has an LC filter on the input side.
An equivalent circuit diagram of the VVVF inverter, FIGS. 8 and 9 are diagrams for explaining the conventional system, and FIG. 10 is a diagram for explaining the characteristics of the VVVF inverter. 1 ... Pulse generator, 2 ... Rotation frequency calculator, 3 ...
Idling slip detection unit, 4 ... Master controller and brake valve, 5 ... Current command value calculation unit, 6 ... Power running regeneration determination unit,
8 ... Modulation rate calculator, 9 ... Modulation pulse mode calculator, 10 ...
PWM modulator, 11 ... Function device, 12 ... First-order delay compensator, 13 ... Limiter, 14 ... Differential compensator, 15, 21, 31 ... Changeover switch, 16
... Polarity converter, 17 ... Slip frequency calculation section, 20,30 ... Comparison section, 22,32 ... Compensation calculation section.

Claims (3)

[Claims] 1. A variable voltage variable frequency inverter having a filter circuit comprising a reactor and a capacitor connected to an input side thereof and an induction motor connected to an output side thereof, and a rotation frequency calculation means for calculating a rotation frequency of the induction motor. A current command value for the induction motor, and a slip frequency calculation means for calculating a slip frequency based on a deviation between the current command value and the actual current of the induction conductor, and the rotation frequency calculation means. Compensation gain setting means for setting the magnitude of the compensation gain according to the rotation frequency, and differential compensation calculation for the input voltage to the variable voltage variable frequency inverter by the compensation gain set by the compensation gain setting means. And a compensation means for adding and subtracting the differential compensation value to and from the slip frequency. Of calculating the inverter frequency from said rotation frequency calculated by the rotation frequency calculation unit and an output, and a control means for controlling the variable voltage variable frequency inverter based on the inverter frequency, the electric vehicle controller having a. 2. A variable voltage variable frequency inverter having a filter circuit composed of a reactor and a capacitor connected to an input side thereof and an induction motor connected to an output side thereof, and a rotation frequency calculation means for calculating a rotation frequency of the induction motor. A current command value for the induction motor and a slip frequency calculation means for calculating a slip frequency based on a deviation between the current command value and an actual current of the induction motor; and the rotation calculated by the rotation frequency calculation means. Compensation gain setting means for setting the magnitude of compensation gain according to frequency, and differential compensation value by performing differential compensation calculation on the actual current of the induction motor with the compensation gain set by the compensation gain setting means. And a compensation means for adding / subtracting the differential compensation value to / from the slip frequency, an output of the compensation means and the rotation frequency. Calculates the inverter frequency from said rotation frequency that is calculated by the number calculating means, and control means for controlling the variable voltage variable frequency inverter based on the inverter frequency, the electric vehicle controller having a. 3. The compensating means is configured to add a differential compensation value and the slip frequency when the electric vehicle is running, and subtract the differential compensation value from the slip frequency when the electric vehicle is regenerated. The electric vehicle control device according to any one of claims 1 to 2.