JP4616136B2 - Operation method of electric power converter and train - Google Patents

Description

  The present invention relates to an operation method of a power converter having an inverter of an electric vehicle and a converter (hereinafter referred to as a PWM converter) that is controlled by pulse width modulation, and in particular, generates harmonics during switching by the carry of the PWM converter. The present invention relates to a driving method to be suppressed.

  In recent years, it has become widespread to organize trains using inverter-driven railway vehicles that use power converters. The converter for electric power used for an inverter drive system has an essential configuration for a converter that converts alternating current into direct current. As such a converter, forward conversion and reverse conversion are performed without switching in the same circuit, and the AC side current waveform is close to a sine wave, and the content of low-order harmonics is small, and therefore, the bridge connection is made. A PWM converter that employs a pulse width modulation method (PWM) in which self-extinguishing switching elements are anti-parallel to each diode is widely used.

  FIG. 7 shows the state of generation of harmonics when the PWM converter is subjected to pulse width modulation control. That is, in the case of one converter, the power supply side has few components due to switching, centering on a frequency 2 fs that is twice the frequency fs of a pulse width modulation control carrier (hereinafter also referred to as carrier). Also appears. In this figure, the existence after the component (fourth harmonic) centering on the frequency 4fs which is four times the carrier frequency fs appearing in the envelope A is omitted, and the shape of the harmonic is also the sideband wave. It is displayed including existence.

  In a train or the like equipped with a large number of such PWM converters, low-order harmonics with a low content rate are multiplexed and cannot be ignored.

  In a drive system in which a large number of railway vehicles using converters are knitted, a plurality of units each consisting of m PWM converters are provided on the secondary side of a transformer that receives single-phase alternating current from an overhead wire in order to reduce the generated harmonics. In the control apparatus for a train train comprising a plurality of AC electric vehicles that are controlled so that the phase difference of the carrier for pulse modulation control among these m converters is 180 ° / m, Means for distributing different phase references to at least two or more of the units in the train train, each AC electric vehicle having means for holding the distributed phase references, the held phase references and each conversion in the unit The pulse width modulation control is performed by a train train control device provided with means for setting the carrier phase reference for each converter based on the converter phase reference preset for each unit. Operated with a phase difference to the carrier of use, by applying a carrier phase difference operating method, it has been proposed to suppress the occurrence of lower order harmonics (e.g., see Patent Document 1).

  FIG. 8 shows the state of generation of harmonics when the carrier phase difference control method is applied to two PWM converters subjected to pulse width modulation control. That is, when PWM control is performed by giving a phase difference of 90 ° (180 ° / 2) to the carrier (frequency fs) of one converter and the other converter, for the component centering on the second harmonic 2fs, A phase difference of 180 ° cancels each other, and a component centered on the quadruple frequency 4fs appears as the lowest low-frequency component.

  FIG. 9 shows the state of generation of harmonics when operating by applying the carrier phase difference control method to four PWM converters subjected to pulse width modulation control. That is, when PWM control is performed by giving a phase difference of 45 ° (180 ° / 4) to the carrier of one PWM converter and the other PWM converter, the component centered on the frequency 2fs that is twice the carrier frequency fs is 180 °. And a component centered at a frequency 4fs that is four times the carrier frequency fs is also canceled, and a component centered at a frequency 8fs that is eight times the carrier frequency fs appears as the lowest frequency component. .

  In this way, by applying the carrier phase difference control method to the PWM converters of a plurality of power converters, by supplying a carrier for pulse width modulation control with a phase difference for each PWM converter, In addition, it is possible to reduce a component centered on a low-order frequency of the carrier frequency fs (hereinafter referred to as a low-order harmonic). The carrier phase difference provided for each PWM converter is 180 ° / m (m is the number of converters). For example, the relationship between the number of converters and the phase difference is 90 ° for two units, 60 ° for three units, and 45 ° for four units.

  On the other hand, in a conventional inverter-driven railway vehicle, a power converter composed of a converter and an inverter is cooled using a cooling fan. However, when the train is traveling at a high speed, it is possible to cool the power converter by cooling with the traveling wind, and in a train train in which a large number of such inverter-driven vehicles are knitted, It is considered that the power converter mounted on some of the trains in the train train is cooled by running wind without using a cooling fan.

  In such a power converter without a blower that uses traveling wind for cooling, the frequency of the carrier for pulse width modulation control of the converter of the power converter is set lower than that of the power converter with a blower. The converter's heat generation is gradually reduced to improve the operating rate.

  When a train is organized using such a power converter without a blower, it is difficult to make a power converter without a blower for all vehicles due to a lack of cooling capacity at low speed or when stopped. In reality, a power converter with a fan and a power converter without a fan are mixed during knitting. However, the power converter with a blower and the power converter without a blower have different cooling capacities. Therefore, under the same operating conditions, the power converter without a blower is under severe thermal conditions.

  In the operation of such a fanless power converter, a reduction in cooling capacity is compensated for by reducing the carrier frequency fs used for pulse width modulation control.

  When a specific power converter in which the carrier frequency fs for pulse width modulation control is set low in the power converter in the train organization to which the carrier phase difference operation method is applied as described above, the carrier It becomes difficult to cancel the harmonic components that should be canceled by the phase difference operation, which may adversely affect communication facilities and signal facilities.

The generation state of harmonics in this case will be described with reference to FIG. In this case, consider a case where the carrier phase difference control method is applied to a unit composed of three power converters with cooling fans and one power converter without fans. Assume that the converter of each power converter is supplied with a phase difference of 45 ° to the carrier. Since the carrier supplied to the three power converters with a blower is given a phase difference of 45 °, low-order harmonics having a phase relationship of 180 ° cancel each other, and there is no partner to cancel. The second (secondary) harmonic 2fsb is generated. On the other hand, since one power converter without a blower has no counterpart to cancel out the lower harmonics, the second harmonic 2fsbl is generated.
Japanese Patent No. 26667812

  The present invention is a vehicle that forms a train, and includes a vehicle equipped with an inverter cooled by a cooling blower and a power converter having a PWM converter (hereinafter sometimes referred to as a power converter with a blower) and cooling by the blower. To compensate for the lack of cooling capacity of fanless power converters when vehicles equipped with inverters and PWM converters that do not perform power conversion (hereinafter sometimes referred to as fanless power converters) are mixed. It aims at providing the operating method of the converter for electric power.

  In addition, the present invention provides a method for operating a power converter, in which when the frequency of a carrier for pulse width modulation control (hereinafter sometimes referred to as a carrier) of a fanless power converter is lowered, An object of the present invention is to provide an operation method of a power converter that reduces the influence of harmonics of the power.

In order to solve the above problems, the present invention provides a method for operating a power converter in a train formed by connecting a plurality of railway vehicles equipped with a power converter controlled by pulse width modulation. One or more power converters that are cooled by the cooling fan when a power converter that is cooled by the cooling fan and a power converter that is not cooled by the cooling fan are mixed. Are grouped, and one or more power converters that are not cooled by the cooling fan are grouped, and each of the groups is operated by a carrier phase difference method using an independent carrier frequency.
In addition, the present invention provides a power converter with a blower that is pulse-width-modulated and cooled by the cooling fan, and a converter for power-free blower that is pulse-width-modulated and not cooled by the cooling fan. And a first train that is composed of one or more power converters with a blower, and is controlled at a common carrier frequency, Each of the power converters of the first group, comprising a second group of one or more of the blower non-power converters, the second group being controlled at a common carrier frequency and different from the first group. Is controlled using a carrier whose phase is shifted between the power converters in the group, and each power converter in the second group is phase-shifted between the power converters in the group. Stagger It was to be controlled by using the carrier.

Furthermore, the present invention provides a carrier frequency of a group consisting of one or more power converters that are not cooled by the cooling fan, and one or more power converters that are cooled by the cooling fan. Or the carrier frequency of the second group is set to be lower than the carrier frequency of the first group.

Further, according to the present invention, when the carrier phase difference method includes m power converters constituting the group, the carrier phase difference scheme is [180 ° / m] on the carriers of the power converters constituting the group. Or a phase difference of [180 ° / m] between the power converters constituting each group when there are m power converters constituting each group. It was made to control using the carrier which attached.

According to the present invention, the carrier frequencies of the first and second groups are set so that the harmonics of the carriers of each group do not fall within the same frequency band, or the carriers of the first and second groups The frequency was set so that the harmonics of the carriers in each group would not be in the same frequency band.

The present invention further sets the frequency of the carrier of each group so that the harmonics of the carrier of each group are in the same frequency band, and the harmonics of the carrier of each group in the same frequency band are The phase of the carrier frequency of the power converter is set so as to have a phase difference that cancels each other, or the carrier frequency of the first and second groups is a frequency band in which the harmonics of the carrier of each group are the same The carrier phase of the power converter was set so as to have a phase difference in which the harmonics of the carriers of each group in the same frequency band cancel each other.

  ADVANTAGE OF THE INVENTION According to this invention, the deterioration and destruction of a switching element by lack of cooling capacity can be suppressed in the converter for electric power without a fan for rail vehicles.

  According to the present invention, in a power converter for a railway vehicle, when a power converter with a fan and a power converter without a fan are mixed during train formation, each power converter is operated in a carrier phase difference operation. The generation of low-order harmonics of the carrier frequency of the PWM converter at the time can be suppressed.

  Embodiments of a method for operating a power converter according to the present invention will be described below with reference to the drawings. FIG. 1 is a diagram for explaining an example of the arrangement of power converters in a train formation to which the method for operating a power converter according to the present invention is applied. The train has vehicles 50-1 to 50-6, and the vehicles 50-1 to 50-4 are equipped with power converters 1-1 to 1-4 with a blower, respectively. Vehicles 50-5 and 50-6 are equipped with fanless power converters 2-1, 2-2, respectively.

  The configuration of the power converter mounted on each vehicle will be described with reference to FIG. The blower-equipped power converter 1 includes a PWM converter 11, a smoothing capacitor 12 that forms a DC intermediate circuit, an inverter 13, and a blower 14. The fanless power converter 2 includes a PWM converter 21, a smoothing capacitor 22 that forms a DC intermediate circuit, and an inverter 23. AC power collected from the overhead line via the current collector 3 is supplied from the primary winding 41 of the main transformer 4 to the power converters 1 and 2 via the secondary winding 42.

  The operation method of the power converter according to the present invention in a train having such a configuration will be described. First, grouping of power converters when the carrier phase difference control method is applied will be described. In FIG. 1, the power converters with fan 1-1 to 1-4 are connected to a power converter group with fan (hereinafter sometimes referred to as a group with fan), and a power converter without fan 2-1 and 2- 1 is grouped into a fanless power converter group (hereinafter also referred to as a fanless group).

  Since the group with a blower includes four power converters 1-1 to 1-4, when applying the carrier phase difference control method, the carrier phase difference is 45 °. Since the fanless group includes two power converters, when applying the carrier phase difference control method, each carrier phase difference is 90 °.

  The generation state of low-order harmonics in the case of such a configuration will be described with reference to FIG. In the group with a blower, as shown in FIG. 9, the frequency component 2 fsb component twice the carrier frequency fsb and the four frequency component component 4 fsb are canceled out, and the frequency component 8 fsb component eight times appears. On the other hand, in the fanless group, as shown in FIG. 8, the frequency component 2fsbl, which is twice the carrier frequency fsbl, is canceled, and the frequency component 4fsbl, which is four times, appears. At this time, since the carrier frequency fsb (for example, 900 Hz) of the group with a blower is set higher than the carrier frequency fsbl (for example, 600 Hz) of the group without a blower, 4fsb is 3600 Hz, 8fsb is 7200 Hz, 4fsbl is 1200 Hz, and 8fsbl Becomes 4800 Hz, the same harmonic band does not appear, and the lower harmonics of each group can be reduced.

  In this way, by setting the relationship between the carrier frequency fsb of the power converter with a blower and the carrier frequency fsbl of the power converter without a blower to a frequency relationship in which those harmonics do not overlap, the knitting is equipped with a blower. Even when a power converter and a power converter without a blower coexist, generation of low-order harmonics in the entire knitting can be suppressed. Since higher harmonics are attenuated, it is not a problem.

  With reference to FIG. 4, another example of the arrangement of power converters in train formation to which the operation method of the present invention is applied will be described. The train has vehicles 50-1 to 50-9, and the vehicles 50-1 to 50-4 and the vehicles 50-7 to 50-9 are respectively power converters 1-1 to 1-4 with a blower. 1-5 to 1-6. Vehicles 50-5 and 50-6 are equipped with fanless power converters 2-1, 2-2, respectively.

  An operation method of the power converter in the train having such a configuration will be described. First, grouping of power converters when the carrier phase difference control method is applied will be described. In FIG. 4, the power converters with fan 1-1 to 1-4 are grouped with a first fan, the power converters with fan 1-5 to 1-7 are grouped with a second fan, and power without a fan. The converters 2-1 and 2-1 are set as a fanless group.

  Since the first fan-equipped group includes four fan-mounted power converters 1-1 to 1-4, when applying the carrier phase difference control method, the carrier phase difference is 45 °. . In the second group with a blower, since three power converters 1-5 to 1-7 with a blower are included, the carrier phase difference is set to 60 ° when the carrier phase difference control method is applied. . Since the fanless group includes two fanless power converters 2-1, 2-2, the carrier phase difference is 90 ° when the carrier phase difference control method is applied.

  The generation state of low-order harmonics in the case of such a configuration will be described with reference to FIG. In the first group with a blower, as shown in FIG. 9, the frequency 2fsb component that is twice the carrier frequency fsb and the component of the frequency 4fsb that is four times the frequency are canceled, and the frequency 8fsb that is eight times the carrier frequency fsb is the lowest. Appears as a frequency component. In the second group with a blower, the frequency 2fsb component twice the carrier frequency fsb and the frequency 4fsb component four times cancel each other, and the 6 times frequency 6fsb appears as the lowest frequency component. In the fanless power converter loop, as shown in FIG. 8, the component of the frequency 2fsbl, which is twice the carrier frequency fsbl, is canceled, and the frequency 4fsbl, which is four times, appears as the lowest frequency component. At this time, since the carrier frequency fsb (for example, 900 Hz) of the group with a fan is set higher than the carrier frequency fsbl (for example, 600 Hz) of the group without a fan, 4fsbl is 1200 Hz, 6fsb is 5400 Hz, 8fsbl is 4800 Hz, and 4fsb Is 3600 Hz, and 8fsb is 7200 Hz, so that low-order harmonics can be reduced without interfering with each other.

  In addition, a case will be described in which three power converters with a blower and one power converter without a blower are being knitted. As shown in FIG. 10, when the carrier phase difference control method of 45 ° phase difference is performed with all the power converters as one group, the carrier for one power converter with a blower and the power converter without a blower is used. Components of frequencies 2fsb and 2fsbl that are twice the frequencies fsb and fsbl appear. In order to solve such a problem, in the present invention, three power converters with a blower are operated as one group by applying a carrier phase difference control method with a phase difference of 60 °, and there is no single blower. A normal control method is applied to the power converter. Thus, by dividing each power converter with a fan and without a fan, and adopting the carrier phase difference control method in each group (in this example, the power converter without a fan is 1 Since it is a stand, the group without a blower cannot perform the carrier phase difference control method and performs a normal operation), and can operate while suppressing the generation of harmonics as much as possible, as shown in FIG.

Next, another embodiment of the present invention will be described. In this embodiment, the carrier frequency of the PWM converter that constitutes the power converter without a blower is the high frequency obtained by the carrier phase difference control of the power converter without the blower, and the PWM converter that constitutes the power converter with a blower. By setting the frequency to be the same frequency as the generated harmonic band and controlling the carrier phase of the power converter with a blower, a harmonic having a phase difference from the harmonic generated by the power converter without a blower is generated. Thus, harmonics generated by the power converter without a blower can be canceled out.

The figure explaining the example of arrangement | positioning of the converter for electric power in the train organization to which the driving | operation method of this invention is applied. The figure explaining the structure of the converter for electric power to which this invention is applied. The figure explaining the generation | occurrence | production of the harmonic at the time of the operating method of this invention being applied (the 1). The figure explaining the other example of arrangement | positioning of the converter for electric power in the train organization to which the driving | running method of this invention is applied. The figure explaining the generation | occurrence | production of the harmonic at the time of the operating method of this invention being applied (the 2). The figure explaining the generation | occurrence | production of the harmonic at the time of the operating method of this invention being applied (the 3). The figure explaining the condition of the harmonic generation of a PWM converter. The figure explaining the condition of the harmonic generation at the time of carrying out carrier phase difference operation of two PWM converters. The figure explaining the condition of the harmonic generation at the time of carrying out carrier phase difference operation of four PWM converters. The figure explaining the condition of the harmonic generation at the time of carrying out carrier phase difference driving | operation of three PWM converters with a fan, and one PWM converter without a fan.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Power converter with a fan, 11 ... PWM converter, 12 ... Smoothing capacitor, 13 ... Inverter, 14 ... Blower, 2 ... Power converter without a fan, 21 ... PWM converter, 22 ... Smoothing capacitor, 23 ... Inverter, 3 ... current collector, 4 ... main transformer, 50 ... vehicle.

Claims (10)

A method of operating a power converter in pulse width train railway vehicle equipped with a modulated controlled Ru power for converter and multiple two joining to organize,
When a power converter that is cooled by a cooling fan and a power converter that is not cooled by a cooling fan are mixed during train formation,
Group one or more power converters that are cooled by the cooling fan, group one or more power converters that are not cooled by the cooling fan,
A method for operating a power converter , wherein each of the groups is operated by a carrier phase difference method using an independent carrier frequency . The operation method of the power converter according to claim 1,
The carrier frequency of the group composed of one or more power converters that are not cooled by the cooling fan is the group frequency composed of one or more power converters that are cooled by the cooling fan. A method for operating a power converter, wherein the power converter is set lower than a carrier frequency . A method of operating a power converter according to claim 1 or claim 2,
In the carrier phase difference method, when there are m power converters constituting the group, a phase difference of [180 ° / m] is given to the carriers of the power converters constituting the group. A method for operating a power converter, characterized in that: In the operating method of the power converter according to any one of claims 1 to 3,
  A method for operating a power converter, wherein the frequency of the carrier of each group is set so that the harmonics of the carrier of each group do not have the same frequency band. In the operating method of the power converter according to any one of claims 1 to 3,
  The frequency of the carrier of each group is set so that the harmonics of the carrier of each group are in the same frequency band, and the phase difference in which the harmonics of the carriers of each group in the same frequency band cancel each other is set. A method of operating a power converter, wherein the phase of the frequency of the carrier of the power converter is set so as to have. A power converter with a blower that is pulse width modulated and is cooled by the cooling blower;
Pulse train modulation controlled, and a train that is connected to a plurality of vehicles equipped with at least one of a blower-less power converter that is not cooled by the cooling blower,
A first group consisting of one or more power converters with a blower and controlled at a common carrier frequency;
A second group that is configured with one or more blower-free converters and is controlled by a common carrier frequency at a frequency different from the first group;
Each power converter of the first group is controlled using a carrier whose phase is shifted between each power converter in the group,
Wherein each power converter of the second group, a train, characterized in that it is controlled by using the carrier obtained by shifting the phase between each power converter in the group. In the train set according to claim 6,
  The train train according to claim 2, wherein the carrier frequency of the second group is set lower than the carrier frequency of the first group. In the train set according to claim 6 or 7,
  When there are m power converters constituting each group, the control is performed using a carrier having a phase difference of [180 ° / m] between the power converters constituting each group. A featured train. In the train set according to any one of claims 6 to 8,
  The train train according to claim 1, wherein the carrier frequencies of the first and second groups are set such that the harmonics of the carriers of each group are not in the same frequency band. In the train set according to any one of claims 6 to 8,
  The carrier frequencies of the first and second groups are set so that the harmonics of the carriers of each group are in the same frequency band, and the carrier phase of the power converter is the same frequency band of each group. A train train set so as to have a phase difference in which carrier harmonics cancel each other.

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