JP6890087B2 - Railroad vehicles, active filter devices for railroad vehicles, and railroad systems - Google Patents

Description

The present invention relates to an inductive interference suppression technique during operation of a railroad vehicle, which is driven by an induction motor controlled by a variable voltage / variable frequency inverter.

FIG. 1 shows a main circuit configuration of a typical railway vehicle control device that controls an induction motor by a variable voltage / variable frequency inverter (hereinafter referred to as “VVVF inverter”). In this circuit, the DC voltage collected from the overhead wire 001 by the pantograph 002 is supplied to the VVVF inverter 006 via the LC low-pass filter circuit 101 configured by connecting the inductor 003 and the capacitor 005. The VVVF inverter 006 converts the DC voltage into a variable voltage / variable frequency three-phase AC to control the induction motor 007.

In railway vehicles, it is necessary to consider inductive interference caused by the current intermittently controlled by the switching element used in the VVVF inverter 006. That is, the return current i generated when performing a wide range of variable frequency operation from low frequency to high frequency flows to the rail 012 via the wheel 011 as shown in FIG. The induction of the harmonic current included in the return current i may affect various security equipment 100 such as traffic lights and railroad crossings. Therefore, for example, when the AC component included in the return current i is in the commercial frequency band of 50 Hz and 60 Hz, it is necessary to suppress this to, for example, 0.7 A or less.

In a conventional railway vehicle driven by an induction motor controlled by a VVVF inverter, an LC low-pass filter using an inductor and a capacitor on the DC input side is used in order to reduce the AC component contained in the return current (for example, a patent). See FIG. 11 of Document 1). However, in order to reduce the AC component in the commercial frequency band below the above values by this method, it is necessary to increase the values of the inductor and the capacitor. However, in the case of railway vehicles, those with high withstand voltage and large capacity are required, and increasing the values of inductors and capacitors increases the volume of each. In addition, there are restrictions on the space in which they can be installed.

Therefore, in the conventional LC low-pass filter, a large-capacity inductor and a capacitor are required to attenuate the AC component contained in the return current, especially the component below the commercial frequency band, which is economical, spatial, and economical. There was a disadvantage for vehicles.

Japanese Unexamined Patent Publication No. 61-98102

The active filter device described in Patent Document 1 reduces the ripple current of a specific frequency included in the return current generated when controlled by a VVVF inverter without using a reactor or a capacitor for a large-capacity filter. Therefore, a transformer containing an iron core is used (see FIG. 1 of Patent Document 1).

However, in the case of a railroad vehicle, for example, a current of about 500 A flows in the return current, so it is necessary to increase the volume of the transformer in order to prevent magnetic saturation of the added transformer.

Therefore, there is a problem that the entire device mounted on the railroad vehicle cannot be sufficiently miniaturized.

A preferred aspect of the present invention is a pantograph that collects voltage from an overhead wire, a first low-pass filter that is configured by connecting an inductor that suppresses an AC component of the output voltage of the pantograph and a first capacitor, and a first one. A railroad vehicle equipped with a first inverter that converts the output voltage of a low-pass filter into alternating current and an induction motor controlled by the first inverter, and further equipped with an active filter device. is there. The active filter device consists of a voltage detector that insulates and detects the voltage between the terminals of the first capacitor, an active filter control unit that generates a control signal using the output signal of the voltage detector, and an inverter operation based on the control signal. A second inverter is provided, and a second capacitor connected to the output terminal of the second inverter and the high potential terminal of the first capacitor is provided.

Another preferable aspect of the present invention is a pantograph that collects voltage from an overhead wire, a first low-pass filter that is configured by connecting an inductor that suppresses an AC component of the output voltage of the pantograph and a first capacitor, and a first low-pass filter. It is an active filter device including a first inverter that converts the output voltage of the low-pass filter 1 into alternating current and an induction motor controlled by the first inverter, and is mounted on a railroad vehicle driven by the induction motor. This device includes a voltage detector that detects the voltage between the terminals of the first capacitor, an active filter control unit that generates a control signal using the output signal of the voltage detector, and a second inverter that operates based on the control signal. It includes an inverter and a second capacitor connected to the output terminal of the second inverter and the high potential terminal of the first capacitor.

Another preferable aspect of the present invention is a pantograph that collects voltage from an overhead wire, a first low-pass filter that is configured by connecting an inverter that suppresses an AC component of the output voltage of the pantograph and a first capacitor, and a first low-pass filter. A railroad vehicle equipped with a first inverter that converts the output voltage of the low-pass filter 1 into alternating current and an induction electric motor controlled by the first inverter, and a railroad vehicle driven by the induction electric motor, and a low voltage side of the first capacitor. It is a railway system including a rail that is electrically connected to or electrically connected to an overhead wire via a transformer, and a security device that is electrically connected to the rail. In this system, the railroad vehicle is equipped with an active filter device, which generates a control signal using a voltage detector that detects the voltage between the terminals of the first capacitor and the output signal of the voltage detector. The active filter control unit, the second inverter that multiplies the voltage between the terminals of the first capacitor by A based on the control signal, and the second that is connected to the output terminal of the second inverter and the high potential terminal of the first capacitor. It is equipped with a capacitor.

According to the present invention, it is possible to reduce the size of the entire device mounted on a railway vehicle while suppressing the noise component of the return current.

A circuit diagram showing a main circuit configuration of a railroad vehicle. The circuit diagram which shows the main circuit composition and the active filter apparatus of the railroad vehicle of an Example. The circuit diagram which shows the example of the 2nd inverter configuration. The circuit diagram which shows the other example of the 2nd inverter configuration. The graph which shows the frequency characteristic of the return current of an active filter using a nonlinear amplifier. The circuit diagram which shows the main circuit composition and the active filter device of the railroad vehicle of 2nd Example. The circuit diagram which shows the main circuit composition and the active filter device of the railroad vehicle of the 3rd Example.

In the following embodiments, when necessary for convenience, the description will be divided into a plurality of sections or embodiments, but unless otherwise specified, they are not unrelated to each other, and one is the other. There is a relationship between some or all of the modifications, details, supplementary explanations, etc. In addition, in the following embodiments, when the number of elements (including the number, numerical value, quantity, range, etc.) is referred to, when it is specified in particular, or when it is clearly limited to a specific number in principle, etc. Except, the number is not limited to the specific number, and may be more than or less than the number of characteristics.

Furthermore, in the following embodiments, the components (including element steps, etc.) are not necessarily essential unless otherwise specified or clearly considered to be essential in principle. Needless to say. Similarly, in the following embodiments, when referring to the shape, positional relationship, etc. of a component or the like, the shape is substantially the same unless otherwise specified or when it is considered that it is not apparent in principle. Etc., etc. shall be included. This also applies to the above numerical values and ranges.

In the configuration of the invention described below, the same reference numerals may be used in common among different drawings for the same parts or parts having similar functions, and duplicate description may be omitted. When there are a plurality of elements having the same or similar functions, they may be described by adding different subscripts to the same code. However, if it is not necessary to distinguish between a plurality of elements, the subscript may be omitted for explanation.

The notations such as "first", "second", and "third" in the present specification and the like are attached to identify the components, and do not necessarily limit the number, order, or contents thereof. is not it. In addition, numbers for identifying components are used for each context, and numbers used in one context do not always indicate the same composition in other contexts. Further, it does not prevent the component identified by a certain number from having the function of the component identified by another number.

The position, size, shape, range, etc. of each configuration shown in the drawings and the like may not represent the actual position, size, shape, range, etc. in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings and the like.

In the embodiment described below, a configuration is described in which a capacitor and an inverter are used to maintain or reduce the resonance frequency even if the passive element is miniaturized by utilizing the Miller effect that equivalently increases the capacitance value of the capacitor. Will be done. With such a configuration, inductive interference can be suppressed even if the LC low-pass filter is miniaturized.

FIG. 2 shows an embodiment of the active filter device for an electric vehicle of the present invention. The same configurations as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 2, the active filter device includes a voltage sensor 008, an active filter control unit 009, a second inverter 010, and a second capacitor 004.

The voltage sensor 008 electrically insulates and detects the voltage between terminals of the first capacitor 005 (for example, a capacity of 10 mF) by using, for example, a transformer. Since it is not desirable to handle high voltages in the control system, insulation is used to reduce the signal voltage level. Then, the voltage level is returned by the second inverter 010 later.

The output voltage of the voltage sensor 008 is signal-processed by the active filter control unit 009 by an analog circuit or a digital circuit. For example, a voltage of 20 Hz to 100 Hz is extracted by a bandpass filter such as a microcomputer, FPGA (Field Programmable Gate Array), or an analog circuit, and the extracted frequency band signal is given a gain. Further, the signal having the gain is PWM (pulse width modulation) and output from the active filter control unit 009.

Here, the active filter of this embodiment suppresses the flow of the frequency component of 20 Hz to 100 Hz extracted by the bandpass filter to the rail 012. In particular, the safety equipment 100 such as a traffic light connected to the rail 012 is expected to use a signal of about 20 Hz to 100 Hz, for example, a band of 25 Hz, 50 Hz, and 100 Hz. There is. Therefore, it is important not to let this AC component flow on the rail 012 in order to improve the operating accuracy of the safety equipment 100. Specifically, in order to filter at least a part or all of the frequency components in the band of 20 Hz to 100 Hz, the second inverter amplifies a part or all of the band.

In this embodiment, the overhead wire 001 uses a DC voltage, but since the DC overhead wire actually transmits a voltage obtained by rectifying AC to DC, some AC components other than DC are transmitted. Including. Further, when the first inverter 006 is driven, the voltage of the first capacitor 005 fluctuates, and an AC component flows on the rail 012. That is, strictly speaking, there are two noise sources through which the AC component flows through the rail 012, and it can be said that the overhead wire 001 and the first inverter 006.

The output pulse voltage of the active filter control unit 009 is input to the second inverter 010 including the gate driver that drives the switching element. The second inverter 010 is an amplifier that multiplies the voltage between terminals by A.

FIG. 3 is a circuit diagram showing a configuration example of the second inverter 010. In the second inverter 010A shown in FIG. 3, the semiconductor element 201 has a full bridge configuration. The control signal from the active filter control unit 009 controls the switching operation of the semiconductor element 201, and outputs a desired waveform from the output terminal 300 to the second capacitor 004.

When the full bridge configuration of FIG. 3 is used as the second inverter 010, the inverter output pulse of the full bridge configuration can output a positive voltage and a negative voltage with reference to the ground, so only one inverter power supply 202 is required. Further, an LC filter 203 is provided in order to reduce switching noise included in the output pulse.

FIG. 4 is a circuit diagram showing another configuration example of the second inverter 010. In the second inverter 010B shown in FIG. 4, the semiconductor element 301 has a half-bridge configuration. When the half-bridge configuration of FIG. 4 is used as the second inverter 010, two inverter power supplies 302 are required for the inverter output pulse of the half-bridge configuration to output a positive voltage and a negative voltage with reference to the ground. In addition, an inductor 303 is used to smooth the current.

In FIG. 2, the output of the second inverter 010 is connected to the second capacitor 004. It is assumed that the second inverter 010 amplifies the electric power by A times. When the impedance Zc2 of the second capacitor 004 at this time is calculated, it can be shown as Zc2 = 1 / (C2 × (1 + A)). C2 is the capacitance value of the second capacitor 004. As can be seen from the calculated Zc2, it can be seen that the capacitance value of the second capacitor is multiplied by (1 + A). That is, the capacitance value of the second capacitor 004 can be equivalently (1 + A) times. The effect of multiplying the capacitance value of the second capacitor 004 by (1 + A) is known as the Miller effect. According to the Miller effect, it can be said that the capacitor between the input and output of the inverter is equivalent to inserting a capacitor of the size multiplied by the value of the voltage gain A of the inverter between the input and ground. ..

Here, the second inverter 010 is a non-linear amplifier that amplifies the signal by switching as shown in FIGS. 3 and 4. Generally, in a circuit using the Miller effect, a linear amplifier is connected to a second capacitor 004 that amplifies the capacitance. The reason is that the nonlinear amplifier includes a signal that amplifies the capacitance in the output pulse and switching noise, and this switching noise affects peripheral circuits and the like. However, in the railway inverter, the maximum high frequency specification (specification in the highest frequency) of the signal device is 42 kHz, and by selecting an appropriate switching frequency, it is possible to prevent switching noise from affecting the signal device. Therefore, the Miller effect using a non-linear amplifier can be applied to the second inverter 010.

As described above, in this embodiment, the leakage of the signal of 20 Hz to 100 Hz to the rail 012 is reduced. The important bands used in the security equipment 100 connected to rail 012 are, for example, 25 Hz, 50 Hz, 100 Hz. Considering the influence of the switching of the second inverter 010 on the band, the preferable switching frequency condition of the second inverter 010 is sufficiently (for example, 10 to 50 times or more) higher than 25 Hz, 50 Hz, and 100 Hz. Examples thereof include 8.6 kHz and 17.3 kHz, which are practically 20 kHz or less at 5 kHz or higher and have no specification of a signal device.

FIG. 5 shows the frequency characteristics of the return current i when an active filter using a non-linear amplifier is used for the second inverter 010. The data 501 is the data when the first capacitor 005 is miniaturized and the active filter is not adopted. The data 502 is data when the first capacitor 005 is not miniaturized and the active filter is not adopted. The data 503 is data when the first capacitor 005 is miniaturized and an active filter is adopted.

If the filter is made smaller, for example, the capacitor is made smaller, the AC component of the return current increases, which may affect the surrounding signal devices. However, even if the filter is miniaturized, the AC component of the return current i can be reduced by using the active filter. According to FIG. 5, it can be seen that the frequency components of 20 Hz to 100 Hz are suppressed. For example, by compensating the amount of capacitance reduction due to capacitor miniaturization with an active filter, the AC component of the return current i becomes the same return current as before the filter miniaturization, as is clear from the comparison between data 502 and data 503. ..

It is desirable in this embodiment that both the second capacitor 004 and the first capacitor 005 are provided. The reason is that when the frequency characteristic of the second capacitor 004 is poor, a high frequency current is output due to the switching of the second inverter 010. In that case, in order to cut off the high frequency current, it is desirable to simultaneously provide a first capacitor 005 that does not use an active filter.

According to this embodiment, the capacitors constituting the low-pass filter can be miniaturized, and even if the capacitance value of the capacitor decreases, an equivalently large capacitance value can be used by the active filter. Therefore, it is possible to reduce the size of the passive element constituting the low-pass filter and suppress the AC component of the return current that causes a malfunction in the safety equipment such as a traffic light.

FIG. 6 is an active filter device according to the second embodiment, and the same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof is omitted. The present embodiment includes a current sensor 013 that detects the current flowing through the inductor 003, for example, with a logoski coil, and the output voltage of the current sensor 013 is signal-processed by an analog circuit or a digital circuit by the active filter control unit 009. Based on the detected current value, control is performed to multiply the voltage between the terminals of the first capacitor by A.

For example, a current of 20 Hz to 100 Hz is extracted by a bandpass filter such as a microcomputer, FPGA, or an analog circuit, and the extracted frequency band signal is given a gain. Further, the signal having the gain is PWM-modulated and output from the active filter control unit 009. The output pulse voltage of the active filter control unit 009 is input to the second inverter 010 including the gate driver that drives the switching element. The output of the second inverter 010 is connected to the second capacitor 004 via the second low-pass filter 102.

The present embodiment includes a second low-pass filter 102 that removes an AC component included in the output voltage of the second inverter 010. The output of the second inverter 010 includes the signal of the active filter control unit 009 and the carrier wave by PWM modulation. The carrier wave has a higher frequency than the signal of the active filter control unit 009, and this carrier wave may become noise and cause inductive interference. Therefore, the second low-pass filter 102 suppresses inductive interference due to the carrier wave. As the second low-pass filter 102, known configurations such as an inductor and a capacitor LC filter and a smoothing inductor can be used.

FIG. 7 is an active filter device according to the third embodiment, and the same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof is omitted.

This embodiment is an active filter device applied to an AC vehicle. As shown in FIG. 7, AC power is collected from the overhead line 001 that transmits AC power via the pantograph 002. From this AC power, DC power is obtained via a transformer 014 and a converter 015. This DC power is converted into alternating current by the first inverter 006 forming the load motion unit, and drives the induction motor 007. The other mechanism is the same as that of the first embodiment shown in FIG.

According to the examples described above, even if the capacitance value of the passive element constituting the LC low-pass filter of the railway vehicle, for example, the capacitor decreases due to the miniaturization of the capacitor, the capacitance value is equivalently large due to the active filter. Can be used. Therefore, it is possible to suppress the AC component of the return current that affects safety equipment such as traffic lights, which increases when the capacitor is miniaturized, and to miniaturize the passive elements that make up the LC low-pass filter. Although the invention made by the present inventor has been specifically described based on the embodiment, it is said that the present invention is not limited to the above-described embodiment and can be variously modified without departing from the gist thereof. Not to mention.

The above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. Further, it is possible to add / delete / replace a part of the configuration of the embodiment with another configuration.

The embodiments described may be widely used primarily for rail vehicles. According to this embodiment, it is possible to achieve miniaturization of the drive system of a railway vehicle by having an active filter using a capacitor and an inverter.

001 Overhead wire 002 Pantograph 003 Inductor 004 2nd capacitor 005 1st capacitor 006 1st inverter 007 Induction motor 008 Voltage sensor 009 Active filter control unit 010 2nd inverter 011 Wheel 012 Rail 014 Current sensor 014 Transformer 015 Converter

Claims (15)

A pantograph to collect the voltage from the overhead line, a first line connected to the pantograph, and the first low-pass filter you suppress the AC component of the output voltage of the pantograph, connected to the first line A first inverter that converts the output voltage of the first low-pass filter into alternating current, an induction electric motor controlled by the first inverter, and a second that allows a return current from the first inverter to flow through a rail. A railroad vehicle equipped with a railroad track and driven by the induction motor, further equipped with an active filter device.
The first low-pass filter is
With the inductor inserted in series in the first line,
The first line between the inductor and the first inverter and the first capacitor connected to the second line are provided.
The active filter device is
A voltage detector that insulates and detects the voltage between the terminals of the first capacitor, and
An active filter control unit that generates a control signal using the output signal of the voltage detector, and
A second inverter that operates based on the control signal, and
A railway vehicle comprising an output terminal of the second inverter and a second capacitor connected to the first line between the inductor and the first inverter. The railway vehicle according to claim 1, wherein the capacity value of the second capacitor is equivalently increased by the Miller effect. The claim is characterized in that when the second inverter multiplies the voltage between terminals of the first capacitor by A, the capacitance value of the second capacitor is equivalently (1 + A) multiplied by the Miller effect. 2 The railroad vehicle described. The railway vehicle according to claim 1, wherein a second low-pass filter is inserted between the output terminal of the second inverter and the second capacitor. The railway vehicle according to claim 1, wherein the voltage detector includes an ammeter that measures a value of a current input to a high potential terminal of the first capacitor. The railway vehicle according to claim 1, further comprising a transformer and a converter for rectifying the AC voltage of the output of the pantograph. The railway vehicle according to claim 1, wherein the second inverter amplifies the voltage between terminals of the first capacitor for a part or all of the band of 20 Hz to 100 Hz. The railway vehicle according to claim 1, wherein the second inverter operates at a switching frequency of 5 kHz or higher. A pantograph to collect the voltage from the overhead line, a first line connected to the pantograph, and the first low-pass filter you suppress the AC component of the output voltage of the pantograph, connected to the first line A first inverter that converts the output voltage of the first low-pass filter into alternating current, an induction electric motor controlled by the first inverter, and a second that allows a return current from the first inverter to flow through a rail. A railroad vehicle equipped with a railroad track and driven by the induction motor.
The first low-pass filter was connected to an inductor inserted in series in the first line, the first line between the inductor and the first inverter, and the second line. An active filter device mounted on a railroad vehicle equipped with a first capacitor.
A voltage detector that detects the voltage between the terminals of the first capacitor, and
An active filter control unit that generates a control signal using the output signal of the voltage detector, and
A second inverter that operates based on the control signal, and
An active filter device for a railway vehicle, comprising: an output terminal of the second inverter and a second capacitor connected to the first line between the inductor and the first inverter. The output voltage of the second inverter is A times the voltage between the terminals of the first capacitor.
The active filter device for a railway vehicle according to claim 9, wherein the capacitance value of the second capacitor is equivalently (1 + A) multiplied by the Miller effect. The active filter device for a railway vehicle according to claim 9, wherein the second inverter amplifies the voltage between terminals of the first capacitor for a part or all of the band of 20 Hz to 100 Hz. The active filter device for a railway vehicle according to claim 9, wherein the second inverter operates at a switching frequency of 5 kHz or higher. A pantograph to collect the voltage from the overhead line, a first line connected to the pantograph, and the first low-pass filter you suppress the AC component of the output voltage of the pantograph, connected to the first line A first inverter that converts the output voltage of the first low-pass filter into AC, an induction electric motor controlled by the first inverter, and a second that allows a return current from the first inverter to flow through a rail. A railroad vehicle having a railroad track and being driven by the induction motor , the first low-pass filter is between an inductor inserted in series in the first railroad track and the inductor and the first inverter. A railroad vehicle having a first line connected to the first line and a first capacitor connected to the second line.
A rail that is electrically connected to the low voltage side of the first capacitor or is electrically connected to the overhead wire via a transformer.
A security device that is electrically connected to the rail,
In a railway system equipped with
The railroad vehicle is equipped with an active filter device.
The active filter device is
A voltage detector that detects the voltage between the terminals of the first capacitor, and
An active filter control unit that generates a control signal using the output signal of the voltage detector, and
A second inverter that multiplies the voltage between the terminals of the first capacitor by A based on the control signal, and
It includes an output terminal of the second inverter and a second capacitor connected to the first line between the inductor and the first inverter.
Railroad system. The railway system according to claim 13, wherein the second inverter multiplies the signal band including the signal band used by the security device by A. The railway system according to claim 13, wherein the second inverter operates at a switching frequency of 5 kHz or more and 20 kHz or less, which does not include the signal band used by the security device.

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