JPWO2019146091A1 - AC electric car control device - Google Patents

Abstract

The control device (20) of the AC electric vehicle is the first calculated based on the converter output voltage Vd, the converter input current Is, the filter output of the overhead wire voltage Vs output by the AC overhead wire (18), and the converter output current IL. A generator (21 to 25, 28) that generates a converter voltage reference Vc based on a control amount Vsp, a filter output of an overhead wire voltage Vs, and a second control amount Vci calculated based on a converter input current Is. Further, a correction unit (26 to 28) for correcting the converter voltage reference Vc based on the filter output of the overhead wire voltage Vs and the correction amount Vcg calculated based on the converter input current Is is provided.

Description

The present invention relates to a control device for an AC electric train that travels by receiving AC power supplied from an AC overhead wire.

In AC electric vehicles, regulations on inductive interference in a specific frequency band are strictly set in order to prevent malfunction of ground equipment. For this reason, control devices for AC electric vehicles are required to achieve high-precision suppression of harmonic currents.

The following Non-Patent Document 1 describes a technique for shifting the phase of a carrier wave applied to a plurality of PWM (Pulse Width Modulation) converters by a predetermined phase as a measure for suppressing a harmonic current. In a plurality of PWM converters, if the phase of the carrier wave is shifted for each PWM converter, the harmonic components generated from the plurality of PWM converters are canceled in a specific frequency band. This makes it possible to reduce the harmonic components in the specific frequency band.

"Technology of PWM Converter for Railway Vehicles (5)" Pages 8-11 Railway Vehicles and Technology September 1999

When a PWM converter is mounted on an AC electric vehicle, it is common to connect a plurality of PWM converters to a main transformer that receives AC power from an AC overhead wire.

Here, the number of main transformers is two, each main transformer is provided with two secondary windings, and one PWM converter is connected to each of the two secondary windings. Consider the case. In this case, there is electromagnetic coupling interference between the two secondary windings of the main transformer, and the total value of the currents generated by the two power converters is affected by the electromagnetic coupling interference. Become. However, since the conditions of the two main transformers are the same or the same, even if the above-mentioned conventional method is used, harmonics can be obtained under the condition that the two power converters are always connected. It was possible to suppress the wave current.

On the other hand, in one of the two main transformers, if only one PWM converter is connected to the secondary winding, or in each of the two main transformers, two secondary windings. Even if one PWM converter is connected to each of the two main transformers, if one of the main transformers fails and stops operating, the two main transformers Electromagnetic conditions will be different. Therefore, it is assumed that the suppression of the harmonic current is insufficient only by the above-mentioned conventional method, and there is a problem that the suppression of the harmonic current cannot be effectively performed.

The present invention has been made in view of the above, and is an AC electric vehicle capable of effectively suppressing harmonic currents regardless of the connection status between the main transformer and the PWM converter or the operating status of the PWM converter. The purpose is to obtain the control device of.

In order to solve the above-mentioned problems and achieve the object, the present invention is mounted on an AC electric vehicle having a converter device that converts an AC voltage output from an AC overhead wire and applied via a main transformer into a DC voltage. It is a control device for an AC electric vehicle that controls the operation of the converter device. The control device of the AC electric vehicle has a converter output voltage, a converter input current, a filter output of the overhead wire voltage output by the AC overhead wire, a first control amount calculated based on the converter output current, and a filter output of the overhead wire voltage. And a generator that generates a converter voltage reference based on a second control amount calculated based on the converter input current, and a first correction calculated based on the filter output of the overhead wire voltage and the converter input current. A correction unit for correcting the converter voltage reference based on the amount is provided.

According to the control device for the AC electric vehicle according to the present invention, the harmonic current can be effectively suppressed regardless of the connection status between the main transformer and the PWM converter or the operating status of the PWM converter. Play.

Functional block diagram showing a configuration including a control device for an AC electric vehicle according to an embodiment. The figure which provides the explanation of the operation of the main part of the control device in an embodiment. A block diagram showing an example of a hardware configuration for realizing the functions of the first arithmetic processing unit to the eighth arithmetic processing unit in the embodiment. A block diagram showing another example of a hardware configuration for realizing the functions of the first arithmetic processing unit to the eighth arithmetic processing unit in the embodiment. A block diagram showing specific processing contents of signal input processing and AD conversion processing in the embodiment. The figure which shows the structure of the control device applied to the AC electric vehicle of the structure different from FIG.

The control device for the AC electric vehicle according to the embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, a technique capable of effectively suppressing harmonic currents is disclosed regardless of the connection status between the main transformer and the PWM converter and the operating status of the PWM converter. Therefore, the number of PWM converters connected to the main transformer will be described by exemplifying only one, which is the minimum number. The present invention is not limited to the following embodiments.

Embodiment.
FIG. 1 is a functional block diagram showing a configuration including a control device 20 for an AC electric vehicle according to an embodiment. In FIG. 1, the drive system of the AC electric vehicle is shown on the upper side, and the control device 20 constituting the control system of the AC electric vehicle and mounted on the AC electric vehicle is shown on the lower side.

As shown in FIG. 1, the drive system of the AC electric vehicle includes a panda graph 1, a main transformer 2, a converter device 3 which is a PWM converter, a filter capacitor 5, and a load 4. Hereinafter, the filter capacitor 5 is referred to as "FC5".

AC power from the AC overhead line 18 is input to the panda graph 1. The AC power supplied from the panda graph 1 is input to the primary winding 2a of the main transformer 2. An AC voltage generated in the secondary winding 2b of the main transformer 2 is applied to the converter device 3. The converter device 3 converts the applied AC voltage into a DC voltage. FC5 smoothes the DC voltage of the converter device 3. The load 4 is driven by a DC voltage smoothed by FC5. The load 4 includes an inverter that converts a DC voltage output from the converter device 3 into an AC voltage, an AC motor to which the AC voltage of the inverter is applied, and a railroad vehicle driven by the AC motor.

Next, the configuration of the control device 20 and the functions of each part constituting the control device 20 will be described. As shown in FIG. 1, the control device 20 includes a first arithmetic processing unit 21 to 8th arithmetic processing unit 28, a carrier generation unit 14, a PWM signal generation unit 15, and AD converters 6a to 6d. Be prepared.

The first arithmetic processing unit 21 includes a filter 7a, an adder / subtractor 11a, and a constant voltage control unit 13. The filter 7a is a low-pass filter or a band-pass filter. The first arithmetic processing unit 21 calculates the DC voltage correction amount Vda based on the DC voltage reference Vd * generated internally and the actual converter output voltage Vd. As the converter output voltage Vd, as shown in the figure, the detection value of the AD converter 6a that detects the voltage across the FC5 can be used.

The second operational amplifier 22 includes an operational amplifier 10a. In the operational amplifier 10a, "G1" in the figure represents a gain value. In addition, in other operational amplifiers, each gain value is expressed in the same manner. The operational amplifier 10a calculates the secondary current feedforward amount Isf, which is the feedforward amount of the converter input current, based on the converter output current IL. As the converter output current IL, as shown in the figure, the detection value of the AD converter 6b that detects the current flowing through the DC bus 16 connecting the converter device 3 and the load 4 can be used.

The third arithmetic processing unit 23 includes a filter 7b and a basic sine wave generation unit 8. The filter 7b is a low-pass filter or a band-pass filter. The third arithmetic processing unit 23 calculates the basic sine wave SWF based on the filter output Vs0 of the overhead wire voltage Vs.

The fourth operational amplifier 24 includes an adder / subtractor 11b, an adder / subtractor 11c, a multiplier 12, and an operational amplifier 10b. The fourth arithmetic processing unit 24 calculates the first control amount Vsp based on the DC voltage correction amount Vda, the secondary current feedforward amount Isf, the fundamental sine wave SWF, and the converter input current Is. The first controlled variable Vsp is used to generate the converter voltage reference Vc described later. The DC voltage correction amount Vda is the output of the first arithmetic processing unit 21. The secondary current feedforward amount Isf is the output of the second arithmetic processing unit 22. The basic sine wave SWF is the output of the third arithmetic processing unit 23. As the converter input current Is, as shown in the figure, the detection value of the AD converter 6c that detects the current flowing on the input side of the converter device 3 can be used.

The fifth operational amplifier 25 includes a cosine wave generation unit 9, an operational amplifier 10c, and an adder / subtractor 11d. The fifth arithmetic processing unit 25 calculates the second controlled variable Vci based on the filter output Vs0 of the overhead wire voltage Vs and the converter input current Is. The second controlled variable Vci is used together with the first controlled variable Vsp to generate the converter voltage reference Vc. As the converter input current Is, the value detected by the AD converter 6c can be used. As the filter output Vs0 of the overhead wire voltage Vs, the output of the filter 7b in the third arithmetic processing unit 23 can be used.

The sixth arithmetic processing unit 26 includes a first-order lag element 26a, a filter 26b, an operational amplifier 26c, an effective value calculation unit 26d, differentiators 26e and 26g, and a gain variable unit which is a first gain variable unit. It includes a 26f, multipliers 26h and 26j, and a gain variable portion 26i which is a second gain variable portion. The filter 26b is a bandpass filter.

In the sixth operational amplifier 26, the first-order lag element 26a, the filter 26b, and the operational amplifier 26c constitute the specific harmonic component extraction unit 26A. The specific harmonic component extraction unit 26A is a calculation unit that extracts a specific harmonic component included in the converter input current Is. In AC electric vehicles, regulations on inductive interference in specific frequency bands are strictly set in order to prevent malfunction of ground equipment. Therefore, the sixth arithmetic processing unit 26 including the specific harmonic component extraction unit 26A controls so that the specific harmonic component does not become large.

Further, in the sixth arithmetic processing unit 26, the effective value arithmetic unit 26d, the differentiators 26e and 26g, the gain variable units 26f and 26i, and the multipliers 26h and 26j constitute the variable gain arithmetic unit 26B. The variable gain calculation unit 26B is a calculation unit that calculates the variable gain applied to the operational amplifier 26c of the specific harmonic component extraction unit 26A.

The specific harmonic component extraction unit 26A of the sixth arithmetic processing unit 26 calculates the correction amount Vcg1 based on the converter input current Is and the second variable gain CG2. The correction amount Vcg1 is used to correct the converter voltage reference Vc. The variable gain calculation unit 26B of the sixth calculation processing unit 26 calculates the second variable gain CG2 based on the filter output Is1 of the harmonic component and the first variable gain CG1. As the filter output Is1 of the harmonic component, the output of the filter 26b in the specific harmonic component extraction unit 26A is used. The first variable gain CG1 is the output of the first gain variable unit 26f, and is calculated using the fundamental sine wave SWF. That is, the first variable gain CG1 is generated inside the variable gain calculation unit 26B.

The seventh operational amplifier 27 includes a first-order lag element 27a, a filter 27b, addition / subtractors 27c and 27e, and an operational amplifier 27d. The filter 27b is a bandpass filter.

The seventh arithmetic processing unit 27 is an arithmetic unit that extracts harmonic components included in the return current. The return current is the current that flows through the circuit portion on the ground side. In the case of an AC electric vehicle, the current flowing out from the AC overhead wire 18 returns to the power supply side via a rail which is a circuit portion on the ground side. Rails have railroad security equipment such as track circuits, ground elements, and railroad crossing controllers. Therefore, a seventh arithmetic processing unit 27 is provided so that the harmonic component included in the return current does not affect the railway security equipment. As a technique for reducing the harmonic component included in the return current, a technique for shifting the phase of the carrier wave among a plurality of PWM converters and a technique for making the rising cycle of the carrier wave different from the falling cycle of the carrier wave are known. .. When these known techniques are used, the seventh arithmetic processing unit 27 can be omitted.

The seventh arithmetic processing unit 27 calculates the correction amount Vcg based on the correction amount Vcg1 and the correction amount Vcg2. The correction amount Vcg1 is a correction amount generated by the sixth arithmetic processing unit 26. The correction amount Vcg2 is a correction amount calculated by using the converter input current Is inside the seventh arithmetic processing unit 27. The correction amount Vcg2 is used together with the correction amount Vcg1 to correct the converter voltage reference Vc. The correction amount Vcg1 generated by the sixth arithmetic processing unit 26 and the correction amount Vcg2 generated by the seventh arithmetic processing unit 27 are added by the adder / subtractor 27e. The output of the adder / subtractor 27e is input to the eighth arithmetic processing unit 28 as a correction amount Vcg.

The eighth arithmetic processing unit 28 includes addition / subtractors 11e and 11f. The eighth arithmetic processing unit 28 calculates the converter voltage reference Vc and corrects the converter voltage reference Vc. Specifically, the adder / subtractor 11e calculates the converter voltage reference Vc based on the first controlled variable Vsp and the second controlled variable Vci. Further, the addition / subtractor 11f corrects the converter voltage reference Vc with respect to the converter voltage reference Vc by using the correction amount Vcg. The corrected converter voltage reference Vc1 calculated by the eighth arithmetic processing unit 28 is output to the PWM signal generation unit 15.

As described above, the first arithmetic processing units 21 to 8th arithmetic processing units 28 have a function of a generation unit for generating a converter voltage reference Vc and a function of a correction unit for correcting the converter voltage reference Vc. .. The function of the generation unit is embodied by the first arithmetic processing unit 21 to the fifth arithmetic processing unit 25 and the addition / subtractor 11e in the eighth arithmetic processing unit 28. Further, the function of the correction unit is realized by the sixth arithmetic processing unit 26, the seventh arithmetic processing unit 27, and the adder / subtractor 11f in the eighth arithmetic processing unit 28.

In addition, in FIG. 1, the addition / subtractor 27e provided in the 7th arithmetic processing unit 27 may be provided in the 8th arithmetic processing unit 28. When the addition / subtractor 27e is provided in the eighth arithmetic processing unit 28, the correction amount Vcg1 is output from the sixth arithmetic processing unit 26 to the eighth arithmetic processing unit 28, and is output from the seventh arithmetic processing unit 27. The correction amount Vcg2 is output to the eighth arithmetic processing unit 28, and the correction amount Vcg1 and the correction amount Vcg2 are added by the eighth arithmetic processing unit 28. In the case of this configuration, the correction amount Vcg1 is referred to as "first correction amount Vcg1", and the correction amount Vcg2 is referred to as "second correction amount Vcg2".

The carrier generation unit 14 calculates the carrier SA used for generating the PWM signal based on the basic sine wave SWF.

The PWM signal generation unit 15 generates a PWM signal for driving a switching element (not shown) provided in the converter device 3 based on the converter voltage reference Vc and the carrier SA. The method for generating the PWM signal is known, and the description thereof is omitted here.

Although FIG. 1 shows a configuration having a second arithmetic processing unit 22 for calculating the secondary current feedforward amount Isf, converter control is possible even if the second arithmetic processing unit 22 is omitted.

Next, a more detailed operation of the control device 20 will be described with reference to FIG.

(Operation of the first arithmetic processing unit 21)
The converter output voltage Vd input to the control device 20 is converted into a digital signal by the AD converter 6a. The converted digital signal is input to the filter 7a in the first arithmetic processing unit 21. In the adder / subtractor 11a, the difference between the DC voltage reference Vd * and the output of the filter 7a is calculated. The constant voltage control unit 13 calculates the DC voltage correction amount Vda based on the output of the adder / subtractor 11a.

(Operation of the second arithmetic processing unit 22)
The converter output current IL input to the control device 20 is converted into a digital signal by the AD converter 6b. The converted digital signal is multiplied by the gain G1 by the operational amplifier 10a in the second operational amplifier 22, and the output of the operational amplifier 10a is calculated as the secondary current feedforward amount Isf.

(Operation of the third arithmetic processing unit 23)
The overhead wire voltage Vs input to the control device 20 is converted into a digital signal by the AD converter 6d. The converted digital signal is input to the filter 7b in the third arithmetic processing unit 23, and the filter output Vs0 of the overhead wire voltage Vs is generated. Further, the filter output Vs0 of the overhead wire voltage Vs is input to the basic sine wave generation unit 8, and the basic sine wave SWF is calculated by the basic sine wave generation unit 8.

(Operation of the fourth arithmetic processing unit 24)
The converter input current Is input to the control device 20 is converted into a digital signal by the AD converter 6c. The converted digital signal is input to the adder / subtractor 11c in the fourth arithmetic processing unit 24. Further, the DC voltage correction amount Vda, the secondary current feedforward amount Isf, and the basic sine wave SWF, which are the outputs of the first arithmetic processing units 21 to the third arithmetic processing units 23, are the fourth arithmetic processing units. It is input to 24. Here, the DC voltage correction amount Vda and the secondary current feedforward amount Isf are input to the adder / subtractor 11b in the fourth arithmetic processing unit 24. The addition output Isp of the addition / subtractor 11b is multiplied by the basic sine wave SWF by the multiplier 12, and the output of the multiplier 12 is calculated as the converter input current reference Is *. Further, the deviation ΔIs between the converter input current Is converted into a digital signal by the AD converter 6c and the converter input current reference Is * is calculated by the adder / subtractor 11c. Then, the gain G2 is multiplied by the deviation ΔIs by the operational amplifier 10b, and the output of the operational amplifier 10b is calculated as the first control amount Vsp.

(Operation of the fifth arithmetic processing unit 25)
The converter input current Is converted into a digital signal by the AD converter 6c is input to the cosine wave generation unit 9 in the fifth arithmetic processing unit 25. In the fifth arithmetic processing unit 25, the cosine wave CWF is generated by the cosine wave generation unit 9 based on the converter input current Is. The cosine wave CWF is input to the operational amplifier 10c, and the gain G3 is multiplied by the operational amplifier 10c. The correction amount VL calculated by the operational amplifier 10c and the filter output Vs0 of the overhead wire voltage Vs output from the third arithmetic processing unit 23 are input to the addition / subtractor 11d, and the filter output Vs0 of the overhead wire voltage Vs and the correction amount The deviation from VL is calculated as the second control amount Vci.

(Operation of 6th Arithmetic Processing Unit 26)
The converter input current Is is input to the filter 26b via the first-order lag element 26a. When the response speed of the filter 26b is high, the first-order lag element 26a can be omitted. In the filter 26b, the specific harmonic component Is1 is extracted. As described above, the specific harmonic component Is1 is a specific frequency component that affects the railway security equipment among the frequency components included in the converter input current Is. The specific frequency component may be one band or a plurality of bands. The extracted specific harmonic component Is1 is input to the operational amplifier 26c and the effective value calculation unit 26d.

The effective value calculation unit 26d calculates the effective value Iscf of the specific harmonic component Is1. The effective value Iscf of the specific harmonic component Is1 is input to the differentiator 26e. In the differentiator 26e, differentiating processing is performed on the effective value Iscf of the specific harmonic component Is1. The output of the differentiator 26e is input to the multiplier 26h.

The fundamental sine wave SWF calculated by the third arithmetic processing unit 23 is input to the gain variable unit 26f. The variable gain unit 26f generates a first variable gain CG1 that changes at a period slower than the period of the fundamental sine wave SWF, that is, a period longer than the period of the fundamental sine wave SWF. When the period of the basic sine wave SWF is "T0", the period of change of the first variable gain CG1 is "n × T0". Here, n is a real number larger than 1. The first variable gain CG1 is input to the differentiator 26g. In the differentiator 26g, differentiating processing is performed on the first variable gain CG1. The output of the differentiator 26g is input to the multiplier 26h.

In the multiplier 26h, the effective value Iscf of the specific harmonic component Is1 and the first variable gain CG1 are multiplied. The output of the multiplier 26h is input to the gain variable unit 26i. The output of the multiplier 26h is subjected to integration processing by the gain variable unit 26i. Further, in the gain variable unit 26i, limit processing is performed so that the output of the integration processing does not exceed the limit value on the maximum side and does not fall below the limit value on the minimum side. The limit value on the maximum side is a real value that does not exceed 1. The minimum limit value is a real value larger than 1 and smaller than the maximum limit value. Hereinafter, the limit value on the maximum side is referred to as "maximum gain", and the limit value on the minimum side is referred to as "minimum gain".

In the multiplier 26j, the output of the gain variable unit 26i is multiplied by the default gain DG which is a fixed value. In the description here, the value of the default gain DG is set to "1".

In this way, the multiplier 26j generates a second variable gain CG2 that varies between the minimum gain and the maximum gain.

The second variable gain CG2 is applied to the operational amplifier 26c. That is, in the operational amplifier 26c, a second variable gain CG2, which is not a fixed value, is applied to the specific harmonic component Is1 output from the filter 26b.

(Operation of the 7th arithmetic processing unit 27)
The converter input current Is is input to the filter 27b via the first-order lag element 27a. When the response speed of the filter 27b is high, the first-order lag element 27a can be omitted. In the filter 27b, the fundamental frequency component Is0 is extracted from the converter input current Is. The fundamental frequency is the frequency of the AC overhead wire 18. The output of the first-order lag element 27a that does not pass through the filter 27b and the output of the first-order lag element 27a that passes through the filter 27b are input to the adder / subtractor 27c and subtracted. Therefore, the addition / subtractor 27c outputs a harmonic component obtained by removing the fundamental frequency component Is0 from the converter input current Is. In the operational amplifier 27d, the gain G5 is multiplied by the harmonic component output from the adder / subtractor 27c, and the output of the operational amplifier 27d is calculated as the correction amount Vcg2. Further, in the addition / subtractor 27e, the correction amount Vcg2 and the correction amount Vcg1 output from the sixth arithmetic processing unit 26 are added, and the output of the addition / subtractor 27e is calculated as the correction amount Vcg.

(Operation of the eighth arithmetic processing unit 28)
The first control amount Vsp, which is the output of the fourth arithmetic processing unit 24, and the second control amount Vci, which is the output of the fifth arithmetic processing unit 25, are the addition / subtractor 11e in the eighth arithmetic processing unit 28. Is entered in. In the adder / subtractor 11e, the first control amount Vsp and the second control amount Vcig are added, and the output of the adder / subtractor 11e is calculated as the converter voltage reference Vc. Further, the converter voltage reference Vc and the correction amount Vcg which are the outputs of the seventh arithmetic processing unit 27 are input to the adder / subtractor 11f in the eighth arithmetic processing unit 28. In the adder / subtractor 11f, the converter voltage reference Vc and the correction amount Vcg are added, and the output of the adder / subtractor 11f is calculated as the corrected converter voltage reference Vc1. That is, the converter voltage reference Vc is corrected by the correction amount Vcg.

(Operation of carrier generation unit 14)
The carrier generation unit 14 calculates the carrier SA used for generating the PWM signal based on the basic sine wave SWF input from the third arithmetic processing unit 23.

(Operation of PWM signal generation unit 15)
The PWM signal generation unit 15 generates a PWM signal for driving the converter device 3 based on the converter voltage reference Vc calculated by the eighth arithmetic processing unit 28 and the carrier SA calculated by the carrier generation unit 14. .. The generated PWM signal is output to the converter device 3.

Next, the operation of the main part of the control device 20 in the embodiment will be described with reference to FIG. FIG. 2 is a diagram provided for explaining the operation of the main part of the control device 20 in the embodiment. In particular, FIG. 2 is a diagram for explaining the operation of the variable gain calculation unit 26B in the sixth calculation processing unit 26 of the control device 20.

The time-varying waveform of the first variable gain CG1 is shown in the upper part of FIG. This waveform is the output waveform of the gain variable unit 26f. The time-varying waveform of the differential value of the first variable gain CG1 is shown in the upper middle part of FIG. This waveform is the output waveform of the differentiator 26g. The time-varying waveform of the effective value Iscf of the specific harmonic component Is1 is shown in the middle part of FIG. This waveform is an output waveform of the effective value calculation unit 26d. The time-varying waveform of the differential value of the effective value Iscf is shown in the lower middle part of FIG. This waveform is the output waveform of the differentiator 26e.

Further, in the lower part of FIG. 2, a chart regarding the sign of the gain adjustment amount and the direction of the gain control is shown. The code of the gain adjustment amount is a code relating to the multiplication value of the differential value of CG1 and the differential value of Iscf, and represents the code of the output of the multiplier 26h in the variable gain calculation unit 26B.

In FIG. 2, in the period from time t0 to time t1, the sign of the differential value of CG1 is positive, and the sign of the differential value of Iscf is positive. Therefore, the sign of the gain adjustment amount is positive in this period.

In the period from time t1 to time t2, the sign of the differential value of CG1 is negative, and the sign of the differential value of Iscf is also negative. Therefore, the sign of the gain adjustment amount is positive in this period.

In the period from time t2 to time t3, the sign of the differential value of CG1 is negative, and the sign of the differential value of Iscf is positive. Therefore, the sign of the gain adjustment amount is negative in this period.

In the period from time t3 to time t4, the sign of the differential value of CG1 is positive, and the sign of the differential value of Iscf is negative. Therefore, the sign of the gain adjustment amount is negative in this period.

As shown in the table of FIG. 2, the output of the gain variable unit 26i is calculated by "1- (gain adjustment amount)" with respect to the gain adjustment amount which is the output of the multiplier 26h. Therefore, when the sign of the gain adjustment amount is positive, the output value of the gain variable unit 26i is smaller than 1, and the control in the direction of lowering the gain works. On the other hand, when the sign of the gain adjustment amount is negative, the output value of the gain variable unit 26i is larger than 1, and the control in the direction of increasing the gain works. In this way, the direction of gain control is determined by the output of the multiplier 26h.

According to the above control, even when the effective value Iscf of the specific harmonic component Is1 tends to increase, if the first variable gain CG1 tends to increase, the sign of the gain adjustment amount becomes positive. The gain value is lowered. As a result, the increase of the specific harmonic component Is1 is suppressed. On the contrary, when the effective value Iscf of the specific harmonic component Is1 tends to decrease and the first variable gain CG1 tends to decrease, the sign of the gain adjustment amount becomes negative and the gain The value is raised. As a result, it is possible to effectively suppress the harmonic current while avoiding the situation where the gain value is suppressed more than necessary.

Note that FIG. 2 shows a case where the period of change of the first variable gain CG1 is twice the period of the specific harmonic component Is1, but the present invention is not limited to this example. The period of the first variable gain CG1 may be longer than the period of the fundamental wave, that is, the overhead line voltage Vs.

Next, the hardware configuration for realizing the function of the control device 20 in the embodiment will be described with reference to the drawings of FIGS. 3 to 5. FIG. 3 is a block diagram showing an example of a hardware configuration for realizing the functions of the first arithmetic processing units 21 to 8th arithmetic processing units 28 in the embodiment. FIG. 4 is a block diagram showing another example of the hardware configuration for realizing the functions of the first arithmetic processing units 21 to 8th arithmetic processing units 28 in the embodiment. FIG. 5 is a block diagram showing specific processing contents of the signal input processing and the AD conversion processing in the embodiment.

When the functions of the first arithmetic processing units 21 to 8th arithmetic processing units 28 are realized, as shown in FIG. 3, the processor 200 that performs the arithmetic and the memory 202 in which the program read by the processor 200 is stored. , And the interface 204 for inputting and outputting signals can be included.

The processor 200 may be an arithmetic unit, a microprocessor, a microcomputer, a CPU (Central Processing Unit), or a DSP (Digital Signal Processor). Further, the memory 202 includes a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Program ROM), and an EPROM (registered trademark) (Electrically EPROM). Examples thereof include magnetic discs, flexible discs, optical discs, compact discs, mini discs, DVDs (Digital Versailles Disc), and BDs (Blue-ray® Disc).

The memory 202 stores a program that executes the functions of the first arithmetic processing units 21 to 8th arithmetic processing units 28, and a table referenced by the processor 200. The processor 200 sends and receives necessary information via the interface 204, the processor 200 executes a program stored in the memory 202, and the processor 200 refers to a table stored in the memory 202, thereby performing the above-mentioned arithmetic processing. It can be performed. The calculation result by the processor 200 can be stored in the memory 202.

Further, the processor 200 and the memory 202 shown in FIG. 3 may be replaced with the processing circuit 203 as shown in FIG. The processing circuit 203 corresponds to a single circuit, a composite circuit, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof.

FIG. 5 shows specific processing contents of the signal input processing and the AD conversion processing in the embodiment. The functional blocks 50 of the signal input processing and the AD conversion processing shown in FIG. 5 include an AD conversion processing block 51 of the converter output voltage Vd, an AD conversion processing block 52 of the converter output current IL, an AD conversion processing block 53 of the overhead wire voltage Vs, and a converter. The AD conversion processing block 54 of the input current Is, the signal input processing block 55 of the DC voltage reference Vd *, the input processing block 56 of the gain constants G1 to G5, the input processing block 57 of the filter constant, and the input processing block 58 of the time constant. It is a functional block that is aggregated so that it can be performed collectively by software. The time constant input processing block 58 sets the time constant in the operational amplifiers 10a, 10b, 10c, 26c, 27d configured by the PI (Proportional-Integral) controller or the PID (Proportional-Integral-Differential) controller. It is a process.

Here, when the arithmetic functions of the first arithmetic processing units 21 to 8th arithmetic processing units 28 are realized by the FPGA, it is conceivable to incorporate the constants used for each arithmetic into the FPGA. However, changing the FPGA logic requires special equipment as compared with changing the software logic, which complicates the work. Therefore, for example, when trying to change the constant of each controller at the adjustment stage, the change work cannot be easily performed, and the adjustment takes time.

On the other hand, as shown in FIG. 5, if the settings or changes of the gain constants G1 to G5, the filter constants, and the time constants used in the control calculation are aggregated and read from the software, the adjustment takes time. Does not occur. That is, in the control device 20 according to the present embodiment, the gain constant, the filter constant, and the time constant can be set or changed by changing the software. This eliminates the need for special equipment or procedures such as changing the FPGA built-in constant, facilitating adjustment and shortening the adjustment time.

As described above, according to the control device for the AC electric vehicle according to the embodiment, the converter voltage reference Vc generated based on the first control amount Vsp and the second control amount Vci is corrected by the correction amount Vcg. Therefore, even if the phase of the carrier is not shifted for each PWM converter, the harmonic current of the harmonic current is not affected by the connection status between the main transformer 2 and the converter device 3 or the operating status of the converter device 3. It becomes possible to effectively suppress the suppression. In addition, since the harmonic current can be effectively suppressed, it is possible to improve the robustness against changes in the operating conditions of the AC electric vehicle.

FIG. 6 is a diagram showing a configuration of a control device 20A applied to an AC electric vehicle having a configuration different from that of FIG. The control device 20 of FIG. 1 is configured to monitor the voltage of the primary winding 2a in the main transformer 2 as the overhead wire voltage Vs. However, as shown in FIG. 6, the tertiary winding in the main transformer 2 is monitored. It may be configured to monitor the voltage of 2c. Even in the configuration of monitoring the voltage of the tertiary winding 2c of the main transformer 2, the same effect as that of the control device 20 can be obtained by configuring the control device 20A to be the same as or equivalent to that of FIG.

The configuration shown in the above-described embodiment shows an example of the content of the present invention, can be combined with another known technique, and is configured without departing from the gist of the present invention. It is also possible to omit or change a part of.

1 pandagraph, 2 main transformer, 2a primary winding, 2b secondary winding, 2c tertiary winding, 3 converter device, 4 load, 5 filter capacitor, 6a to 6d AD converter, 7a, 7b, 26b , 27b filter, 8 basic sine wave generator, 9 chord wave generator, 10a-10c, 26c, 27d arithmetic amplifier, 11a to 11f, 27c, 27e adder / subtractor, 12,26h, 26j multiplier, 13 constant voltage control unit , 14 Carrier generator, 15 PWM signal generator, 16 DC bus, 18 AC overhead wire, 20 controller, 21 1st arithmetic processing unit, 22 2nd arithmetic processing unit, 23 3rd arithmetic processing unit, 24th 4 arithmetic processing unit, 25 5th arithmetic processing unit, 26 6th arithmetic processing unit, 26A specific harmonic component extraction unit, 26B variable gain arithmetic unit, 26a, 27a first-order lag element, 26d effective value arithmetic unit, 26e, 26g Differential, 26f, 26i Gain variable unit, 27 7th arithmetic processing unit, 28 8th arithmetic processing unit, 50 Functional block of signal input processing and AD conversion processing, 51 AD conversion processing of converter output voltage Vd Block, 52 converter output current IL AD conversion processing block, 53 overhead wire voltage Vs AD conversion processing block, 54 converter input current Is AD conversion processing block, 55 DC voltage reference Vd * signal input processing block, 56 gain constant G1 ~ G5 input processing block, 57 filter constant input processing block, 58 time constant input processing block, 200 processors, 202 memory, 203 processing circuit, 204 interface.

Claims (7)

It is a control device for an AC electric vehicle that is mounted on an AC electric vehicle having a converter device that converts an AC voltage output from an AC overhead wire and applied via a main transformer into a DC voltage, and controls the operation of the converter device. hand,
The converter output voltage, the converter input current, the filter output of the overhead wire voltage output by the AC overhead wire, and the first control amount calculated based on the converter output current, the filter output of the overhead wire voltage, and the converter input current. A generator that generates a converter voltage reference based on a second control amount calculated based on
A correction unit that corrects the converter voltage reference based on the filter output of the overhead wire voltage and the first correction amount calculated based on the converter input current.
A control device for AC electric vehicles, which is characterized by being equipped with. The first correction amount is a first variable gain calculated based on a specific harmonic component included in the converter input current, an effective value of the specific harmonic component, and a filter output of the overhead wire voltage. The control device for an AC electric vehicle according to claim 1, wherein the AC electric vehicle is calculated based on the first variable gain and the second variable gain calculated based on the first variable gain. The control device for an AC electric vehicle according to claim 2, wherein the first variable gain is a gain that changes in a period longer than the period of the overhead wire voltage. The second variable gain according to claim 2 or 3, wherein the second variable gain is a gain that has been subjected to limit processing so as not to exceed the limit value on the maximum side and not to fall below the limit value on the minimum side. Control device for AC electric vehicles. The correction unit sets the direction of gain control for increasing or decreasing the first correction amount based on the multiplication result of the differential value of the effective value of the specific harmonic component and the differential value of the first variable gain. The control device for an AC electric vehicle according to claim 3 or 4, wherein the determination is made. The correction unit calculates a second correction amount based on the filter output of the overhead wire voltage and the converter input current, and the converter voltage reference is based on the first correction amount and the second correction amount. The control device for an AC electric vehicle according to any one of claims 1 to 5, wherein the AC electric vehicle is corrected. The control device for an AC electric vehicle according to claim 6, wherein the second correction amount is calculated based on a harmonic component obtained by removing a fundamental frequency component from the converter input current.

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