JP2014220947A - Electric power conversion system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device that is able to hinder occurrence of noise in a band lower than AM band.SOLUTION: An electric power conversion device 10 including a switching element has a plurality of switching circuits 21, 22 that separately carry out switching and are connected in parallel. One or more switching circuits 22 out of the plurality of switching circuits 21, 22 have modulation control means 22b that exerts control so as to shift the phase of a predetermined modulation pattern. In this configuration, even if noise of a band lower than AM band occurs due to the switching of a certain switching circuit 21, switching is carried out in another switching circuit 22 in a predetermined modulation pattern in which a phase is shifted so as to muffle by combining with the waveform of the noise. Accordingly, occurrence of noise in a band lower than AM band can be hindered. Also, hindering occurrence of noise enables simplified filter circuit 30 and a cost reduction.

Description

  The present invention relates to a power conversion device that converts input power and outputs the converted power.

  Conventionally, an example of a technology related to a power switching device aimed at reducing the size and weight of a noise filter and reducing the intensity of a radiated electromagnetic wave while reducing manufacturing conditions has been disclosed (see, for example, Patent Document 1). The power switching device includes a control circuit unit that selects a plurality of types of pulse cycle patterns in a predetermined repetition order and arranges them in time sequence to set the pulse cycle of the switching signal.

JP 2006-187173 A

  However, since the switching signals described in Patent Document 1 are selected in a predetermined repetition order and arranged in time sequence, the modulation frequency changes within a unit period. Since the modulation frequency changes like a carrier wave (carrier wave), it appears as noise in the LW (long wave) band lower than the AM (medium wave) band. In particular, when it overlaps with the audible frequency band, it may become a cause of abnormal noise generated in circuit components (for example, a transformer, a capacitor, etc.). Moreover, it is generated as an abnormal sound from a speaker of a radio or audio equipment. In particular, under a weak electric field such as a tunnel, it becomes an unusual noise that tends to be uncomfortable.

  This invention is made | formed in view of such a point, and it aims at providing the power converter device which can suppress generation | occurrence | production of the noise in a band lower than AM band.

  A first invention made to solve the above problems includes switching elements (21a, 22a, 23a,..., 2na), and a predetermined modulation pattern based on a carrier frequency (fc1, fc2, fc3,...) In the power conversion device (10) that converts the input power by switching the switching elements and outputs the converted power, each of the switching circuits performs a switching operation, and a plurality of switch circuits (21, 22, 23,...) Connected in parallel. , 2n), and at least one of the plurality of switch circuits includes modulation control means (21b, 22b, 23b,..., 2nb) that controls the phase of the predetermined modulation pattern to be shifted. It is characterized by having.

  According to this configuration, even when noise in a band lower than the AM band is generated by switching of a certain switch circuit, the other modulation circuit has a predetermined modulation pattern whose phase is shifted so as to be silenced by waveform synthesis with the noise. Switching is performed with. Therefore, the generation of noise in a band lower than the AM band can be suppressed.

  In a second aspect of the present invention, when the plurality of switch circuits are n (n is an integer of 2 or more), the modulation control means sets the phase of the predetermined modulation pattern to 360 degrees / Control is performed so as to shift by n.

  According to this configuration, the occurrence of noise in a band lower than the AM band can be suppressed by shifting the phase of the predetermined modulation pattern by 360 degrees / n.

  The third invention includes switching elements (21a, 22a, 23a,..., 2na), and performs switching of the switching elements with a predetermined modulation pattern based on carrier frequencies (fc1, fc2, fc3),. In the power conversion device (10) for converting the input power and outputting it, each of the plurality of switch circuits (21, 22, 23,..., 2n) that performs the switching and are connected in parallel, Among the switch circuits, one or more switch circuits include modulation control means (21b, 22b, 23b,..., 2nb) for controlling to reverse the predetermined modulation pattern.

  According to this configuration, even when noise in a band lower than the AM band is generated by switching of a certain switch circuit, the other switch circuit has a predetermined modulation pattern inverted so as to be silenced by waveform synthesis with the noise. Perform switching. Therefore, the generation of noise in a band lower than the AM band can be suppressed.

  The “switch circuit” may be a circuit that includes a switching element and performs switching. For example, a converter, an inverter, etc. correspond. The “predetermined modulation pattern” may be one type of modulation pattern (including a periodic pattern), a combination of two or more types, or the modulation pattern may be changed during operation.

It is a schematic diagram which shows the 1st structural example of a power converter device. It is a time chart figure which shows the 1st example of control of a sine wave modulation pattern. It is a time chart figure which shows the example of control of a triangular wave modulation pattern. It is a time chart figure which shows the example of control of a sawtooth wave modulation pattern. It is a time chart figure which shows the 1st example of control of a rectangular wave modulation pattern. It is a schematic diagram which shows the 2nd structural example of a power converter device. It is a time chart figure showing the 2nd example of control of a sine wave modulation pattern. It is a time chart figure showing the 2nd example of control of a rectangular wave modulation pattern. It is a schematic diagram which shows the 3rd structural example of a power converter device. It is a schematic diagram which shows the 4th structural example of a power converter device.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Note that unless otherwise specified, “connecting” means electrically connecting. Each figure shows elements necessary for explaining the present invention, and does not necessarily show all actual elements. When referring to directions such as up, down, left and right, the description in the drawings is used as a reference.

[Embodiment 1]
The first embodiment will be described with reference to FIGS. The power conversion device 10 corresponds to a “converter” and has a function of converting an input voltage Vin (for example, 288 [V]) into a required output voltage Vout (for example, 14 [V]) and outputting the same. A power source Eb is connected to the input terminal Tin of the power converter 10, and a load Z is connected to the output terminal Tout. The power source Eb corresponds to, for example, a battery (secondary battery or the like), a fuel cell, or the like. The load Z corresponds to, for example, a battery separate from the power source Eb, a rotating electric machine (motor generator, generator, electric motor, etc.), a headlamp, and the like. The output voltage Vout may be set to an arbitrary value. You may set in the power converter device 10, and may set based on the signal, data, etc. which are received from an external processor (for example, ECU, computer, etc.).

  A power conversion device 10 illustrated in FIG. 1 includes switch circuits 21 and 22, a filter circuit 30, and the like. The switch circuit 21 corresponds to a “predetermined switch circuit” serving as a reference, and includes a switching element 21a, a modulation control unit 21b, and the like. The switch circuit 22 corresponds to “one or more switch circuits among a plurality of switch circuits”, and includes a switching element 22a, a modulation control unit 22b, and the like. Control is performed in a master-slave relationship in which the switch circuit 21 of the present embodiment operates as a “master” and the switch circuit 22 as a “slave”. Although illustration and description are omitted, control may be performed in a master-slave relationship in which the switch circuit 22 is operated as a “master” and the switch circuit 21 is operated as a “slave”.

  The number of switching elements 21 a included in the switch circuit 21 and the number of switching elements 22 a included in the switch circuit 22 may be arbitrarily set to one or more. The switch circuits 21 and 22 may have the same number or different numbers. Specifically, the number of required switching elements varies depending on the circuit configuration type such as a full bridge type, a half bridge type, a forward type, a push-pull type, and a flyback type.

  The modulation control means 21b controls the switching element 21a to switch with a predetermined modulation pattern, and transmits the synchronization signal Ps2 to the modulation control means 22b. Receiving the synchronization signal Ps2, the modulation control means 22b controls the switching element 22a to switch by shifting the phase of a predetermined modulation pattern. An arbitrary pattern may be set as the “predetermined modulation pattern”. For example, one modulation pattern may be set, two or more modulation patterns may be set, and the modulation pattern may be changed during operation.

  The filter circuit 30 includes a smoothing unit and the like, and a rectifying unit as necessary. The smoothing unit includes a coil (inductor), a capacitor, and the like, and smoothes the output voltage Vout. The rectifying unit includes a rectifying element such as a diode, and performs rectification when the power output by the switching elements 21a and 22a is alternating current.

  A control example of the switch circuits 21 and 22 in the power conversion apparatus 10 configured as described above will be described with reference to FIGS. 2 and 3. FIG. 2 shows an example of control when switching is performed with a predetermined modulation pattern using a carrier wave as a sine wave (odd function waveform). The upper part of FIG. 2 shows a control example of the switch circuit 21 that changes between the upper limit frequency fc1 (1 + δ) and the lower limit frequency fc1 (1-δ) with reference to the carrier frequency fc1. The lower part of FIG. 2 shows a control example of the switch circuit 22 that changes between the upper limit frequency fc2 (1 + δ) and the lower limit frequency fc2 (1-δ) with reference to the carrier frequency fc2. An arbitrary value may be set for δ. The examples shown in the upper and lower stages of FIG. 2 are the same for FIGS. 3 to 5 described later.

  As shown in the figure, the carrier wave (sine wave) is 180 degrees out of phase between the switch circuit 21 and the switch circuit 22. In this embodiment, the switch circuit 22 delays the phase as compared with the switch circuit 21, but the phase may be advanced.

  Specifically, when the carrier wave of the switch circuit 21 is used as a reference, the carrier wave of the switch circuit 22 is controlled to be in reverse phase. Control may be performed so that the modulation period T1 (from time t12 to time t14) of the switch circuit 21 is equal to the modulation period T2 (from time t12 to time t14) of the switch circuit 22 (T1 = T2; time from t12 to time until t14). The carrier frequency increase / decrease may be controlled so that the change period T1a of the switch circuit 21 is equal to the change period T2a of the switch circuit 22 (T1a = T2a; from time t12 to time t13). Further, the change period T1b of the switch circuit 21 and the change period T2b of the switch circuit 22 may be controlled to be equal (T1b = T2b; from time t13 to time t14).

  FIG. 3 shows an example of control in the case of switching with a predetermined modulation pattern using a carrier wave as a triangular wave (odd function waveform). The difference from FIG. 2 is the waveform. The modulation cycle T1 (from time t22 to time t24) of the switch circuit 21 may be controlled to be equal to the modulation cycle T2 (from time t22 to time t24) of the switch circuit 22 (T1 = T2; time from t22 to time). until t24). The increase / decrease in the carrier frequency may be controlled so that the change period T1a of the switch circuit 21 is equal to the change period T2a of the switch circuit 22 (T1a = T2a; from time t22 to time t23). Further, the change period T1b of the switch circuit 21 and the change period T2b of the switch circuit 22 may be controlled to be equal (T1b = T2b; from time t23 to time t24).

  According to the first embodiment described above, the following effects can be obtained.

  (1) The power conversion device 10 includes a plurality of switch circuits 21 and 22 that perform switching and are connected in parallel, and one or more switch circuits 21 and 22 among the plurality of switch circuits 21 and 22 include: The modulation control means 21b and 22b for controlling the phase of a predetermined modulation pattern to be shifted are used (see FIG. 1). According to this configuration, even if noise in a band lower than the AM band is generated by switching of a certain switch circuit 21, the other switch circuit 22 has a predetermined phase shifted so as to be silenced by waveform synthesis with the noise. Switching is performed with a modulation pattern. Therefore, the generation of noise in a band lower than the AM band can be suppressed. Further, since the generation of noise is suppressed, the filter circuit 30 can be simplified and the cost can be reduced.

  (2) The plurality of switch circuits 21 and 22 are set to 2 (n = 2), and the modulation control means 22b shifts the phase of the predetermined modulation pattern by 180 degrees (360 degrees / n) with reference to the predetermined switch circuit 21. It was set as the structure controlled as follows (refer FIGS. 1-3). When the switch circuit 22 is used as a reference, the modulation control means 21b may control so that the phase of a predetermined modulation pattern is shifted by 180 degrees. According to these configurations, generation of noise in a band lower than the AM band can be suppressed by shifting the phase of the predetermined modulation pattern by 180 degrees.

  (3) The modulation control means 22b is configured to control so as to delay the phase (see FIGS. 2 and 3). When the switch circuit 22 is used as a reference, the modulation control means 21b may delay the phase. According to these configurations, noise is canceled by delaying the phase, and as a result, generation of noise in a band lower than the AM band can be suppressed.

  (4) The predetermined modulation pattern has an odd function waveform including a sine wave and a triangular wave (see FIGS. 2 and 3). According to this configuration, when the carrier wave has an odd function waveform, it is possible to suppress the generation of noise in a band lower than the AM band.

  (7) The modulation control means 21b and 22b are configured to control so that one period of the modulation periods T1 and T2 applied to a predetermined modulation pattern is the same (T1 = T2) (see FIGS. 2 and 3). . According to this configuration, when control is performed so that one period of the modulation periods T1 and T2 is the same, generation of noise in a band lower than the AM band can be reliably suppressed.

  (8) The modulation control means 21b and 22b are controlled so that the change periods T1a, T1b, T2a and T2b corresponding to the increase and decrease of the carrier frequencies fc1 and fc2 are the same (T1a = T2a, T1b = T2b). (See FIGS. 2 and 3). According to this configuration, when control is performed so that the change periods corresponding to the increase and decrease of the carrier frequencies fc1 and fc2 are the same, it is possible to reliably suppress the occurrence of noise in a band lower than the AM band.

[Embodiment 2]
The second embodiment will be described with reference to FIGS. Note that the configuration and the like of the power conversion device 10 are the same as those in the first embodiment, and in the second embodiment, differences from the first embodiment will be described in order to simplify the illustration and description. Therefore, the same elements as those used in Embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

  The second embodiment differs from the first embodiment in the carrier wave. Specifically, the first embodiment is an odd function waveform, whereas the second embodiment is an even function waveform. Therefore, the modulation control means 21b and 22b of the second embodiment are different in function from the embodiments. In the present embodiment, as in the first embodiment, an example will be described in which control is performed in a master-slave relationship in which the switch circuit 21 is “master” and the switch circuit 22 is “slave”.

  The modulation control unit 21b operates in the same manner as in the first embodiment, and controls the switching element 21a to switch with a predetermined modulation pattern. Receiving the synchronization signal Ps2 from the modulation control means 21b, the modulation control means 22b controls to switch the switching element 22a by inverting a predetermined modulation pattern.

  FIG. 4 shows an example of control when switching is performed with a predetermined modulation pattern using a carrier wave as a sawtooth wave (even function waveform). The control example shown in FIG. 2 is different from the control example shown in FIG. 2 in that a predetermined modulation pattern is inverted instead of shifting the phase. The modulation cycle T1 (from time t32 to time t34) of the switch circuit 21 may be controlled to be equal to the modulation cycle T2 (from time t32 to time t34) of the switch circuit 22 (T1 = T2; time from t32 to time until t34). The increase / decrease in the carrier frequency may be controlled so that the change period T1a of the switch circuit 21 is equal to the change period T2a of the switch circuit 22 (T1a = T2a; from time t32 to time t33). Further, the change period T1b of the switch circuit 21 and the change period T2b of the switch circuit 22 may be controlled to be equal (T1b = T2b; from time t33 to time t34).

  FIG. 5 shows a control example in which switching is performed with a predetermined modulation pattern by converting the carrier wave into a rectangular wave (even function waveform). FIG. 5 shows a control example for switching the switching elements 21a and 22a by PWM (Pulse Width Modulation). The increase / decrease in the carrier frequency may be controlled so that the change period T1a of the switch circuit 21 is equal to the change period T2a of the switch circuit 22 (T1a = T2a; from time t42 to time t43). Further, the change period T1b of the switch circuit 21 and the change period T2b of the switch circuit 22 may be controlled to be equal (T1b = T2b; from time t43 to time t44).

  According to the second embodiment described above, the following effects can be obtained. Since the configuration of power conversion device 10 is the same as that of the first embodiment, the same effects as (1), (2), (7), and (8) described above can be obtained.

  (5) In the power conversion device 10 that includes the switching elements 21a and 22a, converts the input power by switching the switching elements 21a and 22a with a predetermined modulation pattern based on the carrier frequencies fc1 and fc2, and outputs the converted power , Each of which has a plurality of switch circuits 21 and 22 connected in parallel, and one or more of the plurality of switch circuits 21 and 22 inverts a predetermined modulation pattern. The modulation control means 21b and 22b are configured to control (see FIGS. 1, 4 and 5). According to this configuration, even when noise in a band lower than the AM band is generated by switching of a certain switch circuit 21, the other modulation is reversed so that the other switch circuit 22 is silenced by waveform synthesis with the noise. Perform switching by pattern. Therefore, the generation of noise in a band lower than the AM band can be suppressed.

  (6) The predetermined modulation pattern has an even function waveform including a sawtooth wave and a rectangular wave (see FIGS. 4 and 5). According to this configuration, when the carrier wave has an odd function waveform, it is possible to suppress the generation of noise in a band lower than the AM band.

[Embodiment 3]
The third embodiment will be described with reference to FIGS. The configuration and the like of power conversion device 10 are the same as those in the first embodiment, and in order to simplify the illustration and description, the third embodiment will be described with respect to differences from the first and second embodiments. Therefore, the same elements as those used in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted.

  The third embodiment differs from the first and second embodiments in the number of switch circuits. Specifically, the first and second embodiments are 2 (n = 2), while the third embodiment is different in that 3 (n = 3). In the third embodiment, a switch circuit 23 is newly provided.

  The switch circuit 23 corresponds to “one or more switch circuits among a plurality of switch circuits”, and includes a switching element 23a, a modulation control unit 23b, and the like. In the present embodiment, as in the first and second embodiments, an example will be described in which control is performed in a master-slave relationship in which the switch circuit 21 is “master” and the switch circuits 22, 23 are “slave”. Control may be performed in a master-slave relationship in which any one of the switch circuits 21, 22, and 23 operates as a “master” and a switch circuit other than the “master” operates as a “slave”.

  The modulation control unit 21b transmits the synchronization signal Ps2 to the modulation control unit 22b and transmits the synchronization signal Ps3 to the modulation control unit 23b. Receiving the synchronization signal Ps3, the modulation control means 23b controls the switching element 23a to switch by shifting the phase of a predetermined modulation pattern.

  A control example of the switch circuits 21, 22, and 23 in the power conversion device 10 configured as described above will be described with reference to FIGS. FIG. 7 shows a control example in which the carrier wave is a sine wave (an example of an odd function waveform), and FIG. 8 shows a control example in which the carrier wave is a rectangular wave (an example of an even function waveform).

  As in the first and second embodiments, the upper part of FIG. 7 shows a control example of the switch circuit 21, and the middle part of FIG. Further, the lower part of FIG. 7 shows a control example of the switch circuit 23 that changes between the upper limit frequency fc3 (1 + δ) and the lower limit frequency fc3 (1-δ) with reference to the carrier frequency fc3. As illustrated, the phase of the carrier wave (sine wave) is shifted by 120 degrees (= 360 degrees / 3) between the switch circuits 21, 22, and 23. Although not shown, the triangular wave shown in FIG. 3 can be similarly controlled. In this embodiment, the switch circuits 22 and 23 delay the phase as compared with the switch circuit 21, but the phase may be advanced.

  The modulation period T1 (from time t52 to time t54) of the switch circuit 21, the modulation period T2 (from time t52 to time t54) of the switch circuit 22, and the modulation period T3 (from time t52 to time t54) of the switch circuit 23 (T1 = T2 = T3; from time t52 to time t54). The carrier frequency increase / decrease may be controlled so that the change period T1a of the switch circuit 21, the change period T2a of the switch circuit 22, and the change period T3a of the switch circuit 23 are equal (T1a = T2a = T3a; time) from t52 to time t53). Further, the change period T1b of the switch circuit 21, the change period T2b of the switch circuit 22, and the change period T3b of the switch circuit 23 may be controlled to be equal (T1b = T2b = T3b; from time t53 to time t54). .

  FIG. 8 shows an example of control in the case of switching with a predetermined modulation pattern by converting the carrier wave into a rectangular wave (even function waveform). The uppermost stage (first stage) shows an example of control of the switch circuit 21, the second stage shows an example of control of the switch circuit 22, the third stage shows an example of control of the switch circuit 23, and the lowermost stage (4 FIG. 6 shows a control example of the switch circuit 24 indicated by a two-dot chain line. That is, this is a control example for switching the switching elements 21a, 22a, 23a, and 24a by PWM. The modulation control means 24b of the switch circuit 24 controls the carrier frequency fc4 so as to change between the upper limit frequency fc4 (1 + δ) and the lower limit frequency fc4 (1-δ).

  The increase / decrease change in the carrier frequency in the figure may be controlled so that the change period T1a of the switch circuit 21 is equal to the change period T2a of the switch circuit 22 (T1a = T2a; from time t62 to time t63). The change period T1b of the switch circuit 21 and the change period T2b of the switch circuit 22 may be controlled to be equal (T1b = T2b; from time t63 to time t64). The change period T3a of the switch circuit 23 and the change period T4a of the switch circuit 24 may be controlled to be equal (T3a = T4a; from time t62 to time t63). The change period T3b of the switch circuit 23 and the change period T4b of the switch circuit 24 may be controlled to be equal (T3b = T4b; from time t63 to time t64). As long as the sound can be silenced, the controls shown from the top to the bottom in FIG. 8 may be combined in any way. The modulation period in the case of performing all of the switch circuits 21 to 24 may be controlled so that T1 = T2 = T3 = T4.

  According to the third embodiment described above, the number of switch circuits is different from that of the first and second embodiments, so that the same operational effects as those of the first and second embodiments can be obtained.

[Embodiment 4]
The fourth embodiment will be described with reference to FIG. The configuration and the like of power conversion device 10 are the same as those in the first embodiment, and in order to simplify the illustration and description, the fourth embodiment will be described with respect to differences from the first to third embodiments. Therefore, the same elements as those used in the first to third embodiments are denoted by the same reference numerals and description thereof is omitted.

  The fourth embodiment differs from the first to third embodiments in the number of switch circuits. Specifically, the first and second embodiments are 2, and the third embodiment is 3, whereas the fourth embodiment is different in that n (n> 3). That is, the power conversion device 10 illustrated in FIG. 9 includes n switch circuits 21, 22, 23,.

  In the present embodiment, as in the first to third embodiments, an example will be described in which control is performed in a master-slave relationship in which the switch circuit 21 operates as a “master” and the switch circuits 22, 23,. In addition, control is performed in a master-slave relationship in which any one of the switch circuits 21, 22, 23,..., 2n operates as a “master” and a switch circuit other than the “master” operates as a “slave”. Also good.

  Although not shown, when the carrier wave is an odd function waveform, it is only necessary to control the switching element to switch by shifting the phase by 360 degrees / n as in the control example shown in FIG. Similarly, when the carrier wave is an even function waveform, similarly to the control example shown in FIG. 8, the switching element may be controlled to be switched by PWM.

  According to the above-described fourth embodiment, since the number of switch circuits is different from the first to third embodiments, the same operational effects as the first to third embodiments can be obtained.

[Embodiment 5]
The fifth embodiment will be described with reference to FIG. The configuration and the like of power conversion device 10 are the same as those in the first embodiment, and in order to simplify the illustration and description, the fifth embodiment will be described with respect to differences from the first to third embodiments. Therefore, the same elements as those used in the first to third embodiments are denoted by the same reference numerals and description thereof is omitted.

  The fifth embodiment differs from the first to fourth embodiments in the command system. Specifically, in the first to fourth embodiments, control is performed in a master-slave relationship in which one switch circuit (for example, the switch circuit 21) operates as a “master” and another switch circuit (for example, the switch circuit 22 or the like) operates as a “slave”. It is a command system to do. On the other hand, the present embodiment is different in that it includes a control device 40 that transmits the synchronization signals Ps1, Ps2, etc. to the switch circuits 21, 22, etc., respectively. The control device 40 may be an ECU or a computer, for example, or may be an external processing device.

  10 has n switch circuits 21, 22, 23,..., 2n, as in the fourth embodiment. The control device 40 transmits the synchronization signal Ps1 to the switch circuit 21, transmits the synchronization signal Ps2 to the switch circuit 21, and transmits the synchronization signal Psn to the switch circuit 2n. In other words, it is composed of a star-type command system. The control method may be performed in the same manner as in the first to fourth embodiments. In addition, although the control apparatus 40 of FIG. 10 shows the example provided outside the power converter device 10, you may provide in the power converter device 10. FIG.

  According to the fifth embodiment described above, the command system is different from the first to fourth embodiments. When n = 2, it is possible to obtain the same operational effects as those of the first and second embodiments, and when n = 3, it is possible to obtain the same operational effects as those of the third embodiment, where n> 3. In this case, the same effect as that of the fourth embodiment can be obtained.

[Other Embodiments]
In the above, although the form for implementing this invention was demonstrated according to Embodiment 1-5, this invention is not limited to the said form at all. In other words, various forms can be implemented without departing from the scope of the present invention. For example, the following forms may be realized.

  In the first to fourth embodiments described above, a master / slave type command system is used, and in the fifth embodiment, a star type command system centered on the control device 40 is used (FIGS. 1, 6, 9 and 9). See FIG. Instead of this form, in the case of n> 2, it may be constituted by another command system. Other command systems include, for example, a bus type, a daisy chain type, and a ring type. In the bus type, switch circuits 21, 22, 23,..., 2n are connected to a single signal line, and a synchronization signal is transmitted through the signal line. In the daisy chain type, the modulation control means 21b, 22b, 23b,..., 2nb are connected in a row (a daisy chain), and the synchronization signal is sequentially transmitted through the switch circuit. In the ring type, modulation control means 21b, 22b, 23b,..., 2nb are connected to an annular signal line, and a synchronization signal (also called a token) is transmitted through the signal line. Regardless of which command system is used, the phase of the carrier frequency can be shifted or reversed, so that generated noise can be silenced. Therefore, it is possible to obtain the same effects as those of the first to fifth embodiments.

  In the first to fifth embodiments described above, the carrier frequencies fc1, fc2, and fc3 are symmetrically changed within the range of ± δ with the center frequency (see FIGS. 2 to 5 and 7). Instead of this form, it may be configured to change within a non-symmetrical range with respect to the center frequency. In other words, the range from the center frequency to the upper limit frequency is different from the range from the center frequency to the lower limit frequency. Even if comprised in this way, the noise which generate | occur | produces can be silenced by shifting or inverting the phase of a carrier frequency. Therefore, it is possible to obtain the same effects as those of the first to fifth embodiments.

  In Embodiment 1-5 mentioned above, it was set as the structure which applies the power converter device 10 as a converter (refer FIG.1, FIG.6, FIG.9 and FIG.10). Instead of this form, the power conversion device 10 may be applied as an inverter. Depending on the load Z (for example, a rotating electrical machine), the filter circuit 30 may be unnecessary. Even when applied as an inverter, even if noise occurs in a certain switch circuit, the other switch circuit 22 is silenced by synthesizing the waveform with the noise. Therefore, it is possible to obtain the same effects as those of the first to fifth embodiments.

DESCRIPTION OF SYMBOLS 10 Power converter 21, 22, 23, ..., 2n Switch circuit 21a, 22a, 23a, ..., 2na Switching element 21b, 22b, 23b, ..., 2nb Modulation control means 30 Filter circuit 40 Control device fc1, fc2, fc3 fc4 carrier frequency

Claims (8)

The switching element (21a, 22a, 23a,..., 2na) is used to convert the input power by switching the switching element with a predetermined modulation pattern based on the carrier frequency (fc1, fc2, fc3,...). In the power converter (10) that outputs the
Each of which performs the switching, and has a plurality of switch circuits (21, 22, 23,..., 2n) connected in parallel,
One or more switch circuits among the plurality of switch circuits have modulation control means (21b, 22b, 23b,..., 2nb) for controlling to shift the phase of the predetermined modulation pattern. Conversion device. When the plurality of switch circuits are n (n is an integer of 2 or more),
2. The power conversion device according to claim 1, wherein the modulation control unit controls the phase of the predetermined modulation pattern to be shifted by 360 degrees / n with reference to the predetermined switch circuit.   The power conversion apparatus according to claim 1, wherein the modulation control unit performs control so as to delay the phase.   The power converter according to any one of claims 1 to 3, wherein the predetermined modulation pattern is an odd function waveform including a sine wave and a triangular wave. , 2na including switching elements (21a, 22a, 23a,..., 2na), and switching the switching elements with a predetermined modulation pattern based on carrier frequencies (fc1, fc2, fc3),. In the power converter (10) that outputs the
Each of which performs the switching, and has a plurality of switch circuits (21, 22, 23,..., 2n) connected in parallel,
One or more switch circuits among the plurality of switch circuits have modulation control means (21b, 22b, 23b,..., 2nb) for controlling to invert the predetermined modulation pattern. apparatus.   The power conversion apparatus according to claim 5, wherein the predetermined modulation pattern is an even function waveform including a sawtooth wave and a rectangular wave.   The said modulation control means controls so that one period of the modulation period (T1, T2, T3) concerning the said predetermined modulation pattern becomes the same, The one of Claim 1 to 6 characterized by the above-mentioned. Power converter.   The electric power according to claim 7, wherein the modulation control means controls the change periods (T1a, T1b, T2a, T2b, T3a, T3b) corresponding to the increase / decrease change of the carrier frequency to be the same. Conversion device.

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