Pulse power supply device

Abstract

To output a pulse output voltage with multiple levels at any timing.SOLUTION: A pulse power supply device includes N DC-DC converters, and N inverters. The N DC-DC converters generate a DC voltage between a first DC output terminal and a second DC output terminal. The N inverters include a first switch that short-circuits or disconnects the first DC output terminal and the pulse output terminal of the corresponding DC-DC converter, and a second switch that short-circuits or disconnects the second DC output terminal and the pulse output terminal of the corresponding DC-DC converter. The first DC-DC converter of the N DC-DC converters has an isolation transformer, and the first DC output terminal or the second DC output terminal is connected to a reference potential. The first DC output terminal of an n-th DC-DC converter of the N DC-DC converters is connected to the pulse output terminal of an (n-1)-th inverter of the N inverters.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a pulse power supply. [Background technology]

[0002] A bipolar multilevel inverter (Patent Document 1) is known as a pulse power supply device that periodically switches between three or more levels of voltage and outputs the voltage. The bipolar multilevel inverter includes a short-circuit switch that outputs 0V, and a full-bridge inverter that switches between a positive side voltage and a negative side voltage. The bipolar multilevel inverter can periodically switch between 0V, a positive side voltage, and a negative side voltage. However, in the bipolar multilevel inverter, the absolute values ​​of the positive side voltage and the negative side voltage are the same, and the duty ratio is also 50%. For this reason, the voltage value and duty ratio generated by the bipolar multilevel inverter are limited.

[0003] As such a pulse power supply device, a multilevel inverter of the NPC (Neutral Point Clamped) type is also known. The multilevel inverter of the NPC type uses an NPC circuit using a switch and a diode or a bidirectional switch (T-type NPC). The multilevel inverter of the NPC type can output positive and negative voltages with different absolute values ​​and switch the voltage at a duty ratio other than 50% by generating multiple DC voltages using multiple DC-DC converters. However, even when the multilevel inverter of the NPC type outputs a positive voltage with a small absolute value and a negative voltage with a large absolute value, the withstand voltage of the switch switching the positive voltage with a small absolute value must be made high, just like the switch switching the negative voltage with a large absolute value. The same applies even if the magnitude relationship between the positive voltage and the negative voltage is reversed. For this reason, the cost of the switches in the multilevel inverter of the NPC type is high. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2009 / 145092 [Patent Document 2] Patent No. 6225418 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above, and provides a pulse power supply device that can output a pulse output voltage Vout at multiple levels simply and at low cost. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a pulse power supply device according to the present invention comprises N (N is an integer of 2 or more) DC-DC converters each having a DC input section consisting of a first DC input terminal and a second DC input terminal and a DC output section consisting of a first DC output terminal and a second DC output terminal, transforming a DC voltage input between the first DC input terminal and the second DC input terminal and generating a transformed DC voltage between the first DC output terminal and the second DC output terminal, and N inverters each having a switch and a pulse output terminal and provided in one-to-one correspondence with the N DC-DC converters, and each of the N inverters has a first switch for short-circuiting or disconnecting the first DC output terminal and the pulse output terminal of a corresponding DC-DC converter among the N DC-DC converters, and a second switch for short-circuiting or disconnecting the first DC output terminal and the pulse output terminal of the corresponding DC-DC converter. and a second switch which shorts or disconnects the second DC output terminal and the pulse output terminal of the inverter, and the first switch and the second switch perform complementary switching operations to output a pulse output voltage from the pulse output terminal, a first DC-DC converter among the N DC-DC converters has an isolation transformer between the DC input unit and the DC output unit for transforming a voltage, and the first DC output terminal or the second DC output terminal is connected to a reference potential, the pulse output terminal of the Nth DC-DC converter among the N DC-DC converters is connected to a load, and the first DC output terminal of the nth DC-DC converter (n is an integer not less than 2 and not more than N) is connected to the pulse output terminal of the (n-1)th inverter among the N inverters. Effect of the Invention

[0007] According to the present invention, a pulse output voltage with multiple levels can be output simply and at low cost. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the configuration of a pulse power supply device according to the first embodiment. [Diagram 2] FIG. 2 is a diagram showing a first example of a simulation waveform according to the first embodiment. [Diagram 3] FIG. 3 is a diagram showing a second example of a simulation waveform according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing a third example of a simulation waveform according to the first embodiment. [Diagram 5] FIG. 5 is a diagram showing a fourth example of a simulation waveform according to the first embodiment. [Figure 6] FIG. 6 is a diagram showing the configuration of a pulse power supply device according to the second embodiment. [Figure 7] FIG. 7 is a diagram showing a simulation waveform of the second embodiment. [Figure 8] FIG. 8 is a diagram showing the configuration of a pulse power supply according to the third embodiment. [Figure 9] FIG. 9 is a diagram showing an example of a simulation waveform of the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] FIG. 1 shows a configuration of a pulse power supply 100 according to the first embodiment. The pulse power supply 100 supplies a load 70 with a pulse output voltage Vout that periodically changes to a plurality of levels. The pulse power supply 100 outputs a pulse output voltage Vout that is stabilized to a target potential regardless of the fluctuation of the impedance of the load 70. For example, the pulse power supply 100 is used as a pulse generating device that supplies switching pulses to a plasma generating device. Note that an equivalent circuit of the load 70 is represented by a capacitor 71 and a resistor 72, for example, as shown in FIG. 1. The pulse frequency of the pulse output voltage Vout is about 100 Hz to 10 MHz. In this embodiment, the pulse frequency of the pulse output voltage Vout is 400 kHz.

[0010] The pulse power supply device 100 includes a first DC-DC converter 1-1, a second DC-DC converter 1-2, a first inverter 2-1, a second inverter 2-2, and a pulse control unit 3.

[0011] The first DC-DC converter 1-1 and the second DC-DC converter 1-2 are switching power supply devices including at least a rectifier circuit that rectifies a voltage using a rectifier element, downstream of a switch circuit for power conversion. In the first DC-DC converter 1-1, the rectifier circuit is disposed on the secondary side of a transformer 26-1. Similarly, in the second DC-DC converter 1-2, a rectifier circuit is disposed on the secondary side of a transformer 26-2.

[0012] The first DC-DC converter 1-1 includes a first DC input terminal T11-1, a second DC input terminal T12-1, a first DC output terminal T21-1, and a second DC output terminal T22-1. The first DC input terminal T11-1 and the second DC input terminal T12-1 form a DC input section, and the first DC output terminal T21-1 and the second DC output terminal T22-1 form a DC output section. The first DC input terminal T11-1, the second DC input terminal T12-1, the first DC output terminal T21-1, and the second DC output terminal T22-1 may be electrodes or may be parts of wiring. The same applies to the other terminals. In the first DC-DC converter 1-1, a DC input voltage Vin is supplied between the first DC input terminal T11-1 and the second DC input terminal T12-1. The input voltage Vin may be, for example, a voltage output from a battery, or a voltage obtained by rectifying and smoothing AC power. The second DC input terminal T12-1 is connected to a reference potential (for example, a ground potential of 0 V). As an example, the second DC input terminal T12-1 may be connected to a ground potential. The first DC-DC converter 1-1 converts the supplied input voltage Vin into a desired potential difference V 1 (10 kV in this embodiment) and output between the first DC output terminal T21-1 and the second DC output terminal T22-1. Thereafter, the voltage of the first DC output terminal T21-1 to the second DC output terminal T22-1 is converted to the first DC voltage V 1 The first DC output terminal T21-1 is connected to the reference potential.

[0013] The potential of the first DC output terminal T21-1 is higher than the potential of the second DC output terminal T22-1. As described above, in this embodiment, the potential of the first DC output terminal T21-1 is the reference potential, so the potential of the second DC output terminal T22-2 is changed from the reference potential to the first DC voltage V 1 In other words, the potential difference of the second DC output terminal T22-2 as viewed from the first DC output terminal T21-1 is -V 1 It becomes.

[0014] The second DC-DC converter 1-2 includes a first DC input terminal T11-2, a second DC input terminal T12-2, a first DC output terminal T21-2, and a second DC output terminal T22-2. The second DC-DC converter 1-2 receives an input voltage Vin between the first DC input terminal T11-2 and the second DC input terminal T12-2. The second DC input terminal T12-2 is connected to a reference potential. The second DC-DC converter 1-2 converts the received input voltage Vin into a desired potential difference V 2 (1 kV in this embodiment) and output between the first DC output terminal T21-2 and the second DC output terminal T22-2. Thereafter, the voltage of the first DC output terminal T21-2 to the second DC output terminal T22-2 is converted to the second DC voltage V 2 The potential of the first DC output terminal T21-2 is higher than the potential of the second DC output terminal T22-2.

[0015] In this embodiment, the second DC-DC converter 1-2 generates a DC voltage whose absolute value is smaller than that of the DC voltage generated by the first DC-DC converter 1-1. That is, the second DC voltage V 2 The absolute value of -V 1 is smaller than the absolute value of

[0016] In this embodiment, the first DC-DC converter 1-1 is an isolated switching power supply device and includes a first DC input terminal T11-1, a second DC input terminal T12-1, a first DC output terminal T21-1, a second DC output terminal T22-1, a first primary side switch 21-1, a second primary side switch 22-1, a third primary side switch 23-1, a fourth primary side switch 24-1, a primary side inductor 25-1, a transformer 26-1, a first diode 27-1, a second diode 28-1, a third diode 29-1, a fourth diode 30-1, a secondary side inductor 31-1, a capacitor 32-1, and a voltage control unit 40-1. The first DC input terminal T11-1 and the second DC input terminal T12-1 form a DC input section, and the first DC output terminal T21-1 and the second DC output terminal T22-1 form a DC output section. The first DC input terminal T11-1, the second DC input terminal T12-1, the first DC output terminal T21-1 and the second DC output terminal T22-1 may be electrodes or may be parts of wiring.

[0017] A DC input voltage Vin is supplied between the first DC input terminal T11-1 and the second DC input terminal T12-1 of the first DC-DC converter 1-1. The second DC input terminal T12-1 is connected to a reference potential.

[0018] The first DC-DC converter 1-1 is generally composed of an inverter circuit, a transformer, a rectifier circuit, and a smoothing circuit. The inverter circuit is composed of a first primary side switch 21-1, a second primary side switch 22-1, a third primary side switch 23-1, a fourth primary side switch 24-1, a primary side inductor 25-1, and a primary side coil of a transformer 26-1. The rectifier circuit is composed of a first diode 27-1, a second diode 28-1, a third diode 29-1, and a fourth diode 30-1. The smoothing circuit is composed of a secondary side inductor 31-1 and a capacitor 32-1.

[0019] The first DC-DC converter 1-1 converts the supplied input voltage Vin to an AC voltage using an inverter circuit, transforms it using a transformer 26-1, and converts it to a DC voltage using a rectifier circuit and a smoothing circuit. As described above, in the first DC-DC converter 1-1, the first DC output terminal T21-1 is connected to the reference potential, so the second DC output terminal T22-1 is connected to the reference potential and outputs the first DC voltage V 1 -V subtracted 1 A voltage of −10 kV in this embodiment is generated.

[0020] At this time, the first DC-DC converter 1-1 is set to -V 1 The first DC-DC converter 1-1 controls the switching of the first primary-side switch 21-1, the second primary-side switch 22-1, the third primary-side switch 23-1, and the fourth primary-side switch 24-1 so that the detection value (detected by a detector not shown) of the target potential becomes the target potential. 1 It is possible to generate a voltage of

[0021] In addition, since the first DC-DC converter 1-1 uses the transformer 26-1 to step up the voltage, it is easy to generate a high voltage, for example, with an absolute value of 10 kV or more, and therefore can be suitably used in applications where high voltages are used.

[0022] A specific configuration of the first DC-DC converter 1-1 will be described below. The first primary side switch 21-1 and the second primary side switch 22-1 are connected in series between the first DC input terminal T11-1 and the second DC input terminal T12-1. The third primary side switch 23-1 and the fourth primary side switch 24-1 are connected in series between the first DC input terminal T11-1 and the second DC input terminal T12-1. The connection point between the first primary side switch 21-1 and the second primary side switch 22-1 is referred to as a connection point N2-1, and the connection point between the third primary side switch 23-1 and the fourth primary side switch 24-1 is referred to as a connection point N3-1.

[0023] The first primary side switch 21-1, the second primary side switch 22-1, the third primary side switch 23-1, and the fourth primary side switch 24-1 are, for example, enhancement type N-channel MOSFETs (Metal Oxide Semiconductor Field Effect Transistors). In this case, the drain of the first primary side switch 21-1 is connected to the first DC input terminal T11-1. The drain of the second primary side switch 22-1 is connected to the source of the first primary side switch 21-1. The source of the second primary side switch 22-1 is connected to the second DC input terminal T12-1. In addition, the drain of the third primary side switch 23-1 is connected to the first DC input terminal T11-1. The drain of the fourth primary side switch 24-1 is connected to the source of the third primary side switch 23-1. The source of the fourth primary side switch 24-1 is connected to the second DC input terminal T12-1. A control signal is given to the gates of these switches from the voltage control unit 40-1. At this time, the first primary side switch 21-1 and the second primary side switch 22-1 are controlled to perform complementary switching operations, and the third primary side switch 23-1 and the fourth primary side switch 24-1 are controlled to perform complementary switching operations.

[0024] The primary inductor 25-1 is connected between the connection point N2-1 and one terminal of the primary coil of the transformer 26-1. Note that the primary inductor 25-1 may not be necessary depending on the control method of the first primary switch 21-1, the second primary switch 22-1, the third primary switch 23-1, and the fourth primary switch 24-1. For example, when phase shift control is performed, it is preferable to have the primary inductor 25-1, but when phase shift control is not performed, it can be omitted.

[0025] The transformer 26-1 is used to perform voltage transformation while providing insulation between the DC input section and the DC output section. One terminal of the primary coil of the transformer 26-1 is connected to the primary inductor 25-1, and the other terminal of the primary coil of the transformer 26-1 is connected to a connection point N3-1. The secondary coil of the transformer 26-1 is connected to a diode bridge formed of four diodes (a first diode 27-1, a second diode 28-1, a third diode 29-1, and a fourth diode 30-1).

[0026] The first diode 27-1 and the second diode 28-1 are connected in series such that the anode of the first diode 27-1 is connected to the cathode of the second diode 28-1. The connection point between the first diode 27-1 and the second diode 28-1 is a connection point N4-1. The third diode 29-1 and the fourth diode 30-1 are connected in series such that the anode of the third diode 29-1 is connected to the cathode of the fourth diode 30-1. The connection point between the third diode 29-1 and the fourth diode 30-1 is a connection point N5-1.

[0027] One terminal of the secondary coil of the transformer 26-1 is connected to a connection point N4-1, and the other terminal of the secondary coil of the transformer 26-1 is connected to a connection point N5-1. The cathode of the first diode 27-1 and the cathode of the third diode 29-1 are connected to a connection point N6-1, and the anode of the second diode 28-1 and the anode of the fourth diode 30-1 are connected to a connection point N7-1.

[0028] The secondary inductor 31-1 has one terminal connected to the connection point N6-1 and the other terminal connected to the reference potential and to the first DC output terminal T21-1. The capacitor 32-1 is connected between the first DC output terminal T21-1 and the second DC output terminal T22-1.

[0029] The voltage control unit 40-1 is realized by a processing circuit such as a microcontroller. The voltage control unit 40-1 detects the voltage of the second DC output terminal T22-1, and thereby detects the -V 1 The voltage control unit 40-1 detects the voltage value of -V 1 The first DC-DC converter 1-1 controls the switching duty ratio of the four switches constituting the inverter circuit so that the potential of -V 1 Such a first DC-DC converter 1-1 can generate a voltage of -V between the first DC output terminal T21-1 and the second DC output terminal T22-1. 1 A potential difference of +1 can be generated, and a voltage of negative polarity can be output to the second DC output terminal T22-1.

[0030] In addition, in this embodiment, the second DC-DC converter 1-2 is an isolated switching power supply device and includes a first DC input terminal T11-2, a second DC input terminal T12-2, a first DC output terminal T21-2, a second DC output terminal T22-2, a first primary side switch 21-2, a second primary side switch 22-2, a third primary side switch 23-2, a fourth primary side switch 24-2, a primary side inductor 25-2, a transformer 26-2, a first diode 27-2, a second diode 28-2, a third diode 29-2, a fourth diode 30-2, a secondary side inductor 31-2, a capacitor 32-2, and a voltage control unit 40-2. The first DC input terminal T11-2 and the second DC input terminal T12-2 form a DC input section, and the first DC output terminal T21-2 and the second DC output terminal T22-2 form a DC output section. The first DC input terminal T11-2, the second DC input terminal T12-2, the first DC output terminal T21-2, and the second DC output terminal T22-2 may be electrodes or may be parts of wiring.

[0031] Similar to the first DC-DC converter 1-1, a DC input voltage Vin is supplied between the first DC input terminal T11-2 and the second DC input terminal T12-2 of the second DC-DC converter 1-2. Also, similar to the second DC input terminal T12-1 of the first DC-DC converter 1-1, the second DC input terminal T12-2 is connected to a reference potential.

[0032] The second DC-DC converter 1-2 is generally composed of an inverter circuit, a transformer, a rectifier circuit, and a smoothing circuit. The inverter circuit is composed of a first primary side switch 21-2, a second primary side switch 22-2, a third primary side switch 23-2, a fourth primary side switch 24-2, a primary side inductor 25-2, and a primary side coil of a transformer 26-2. The rectifier circuit is composed of a first diode 27-2, a second diode 28-2, a third diode 29-2, and a fourth diode 30-2. The smoothing circuit is composed of a secondary side inductor 31-2 and a capacitor 32-2.

[0033] The second DC-DC converter 1-2 converts the supplied input voltage Vin to an AC voltage using an inverter circuit, transforms it using a transformer 26-2, and converts it to a DC voltage using a rectifier circuit and a smoothing circuit. As a result, the second DC-DC converter 1-2 outputs a positive second DC voltage V 2 (In this embodiment, 1 kV) is generated.

[0034] At this time, the second DC-DC converter 1-2 is supplied with the second DC voltage V 2 The first primary-side switch 21-2, the second primary-side switch 22-2, the third primary-side switch 23-2, and the fourth primary-side switch 24-2 are switched and controlled so that the detection value (detected by a detector not shown) of V becomes the target potential. As a result, the second DC-DC converter 1-2 outputs a stabilized second DC voltage V between the first DC output terminal T21-2 and the second DC output terminal T22-2. 2 can be generated.

[0035] Furthermore, since the second DC-DC converter 1-2 uses the transformer 26-2 to step up the voltage, it is easy to generate a high voltage, for example, with an absolute value of 10 kV or more, and is therefore suitable for use in applications where high voltages are used.

[0036] However, as described above, in this embodiment, the second DC voltage V 2 Since the input voltage is 1 kV, the second DC-DC converter 1-2 generates a relatively low voltage.

[0037] The specific configuration of the second DC-DC converter 1-2 is substantially the same as that of the first DC-DC converter 1-1, except that the second DC-DC converter 1-2 differs from the first DC-DC converter 1-1 in that the first DC output terminal T21-2 is not connected to the reference potential, and that one terminal of the secondary inductor 31-2 is connected to the connection point N6-2 and the other terminal is not connected to the reference potential but is connected to the first DC output terminal T21-2.

[0038] The voltage control section 40-2 of the second DC-DC converter 1-2 may be realized by a common circuit to the voltage control section 40-1 of the first DC-DC converter 1-1.

[0039] As described above, the transformer 26-2 is provided between the DC input section and the DC output section of the second DC-DC converter 1-2, and the primary side and secondary side of the transformer 26-2 are insulated from each other. Therefore, the potential of the first DC output terminal T21-2 is in a DC floating state inside the circuit of the second DC-DC converter 1-2.

[0040] Here, the first DC output terminal T21-2 in the second DC-DC converter 1-2 is connected to the pulse output terminal T3-1 of the first inverter 2-1 described later, and a period during which it is connected to the reference potential occurs due to switching of the first inverter 2-1. Therefore, the second DC-DC converter 1-2 can detect the voltage of the second DC output terminal T22-2 at the timing when the first DC output terminal T21-2 becomes the reference potential.

[0041] Such a second DC-DC converter 1-2 outputs a stabilized second DC voltage V between the first DC output terminal T21-2 and the second DC output terminal T22-2. 2 A potential difference of 1 kV in this embodiment can be generated.

[0042] As described above, the first DC output terminal T21-2 of the second DC-DC converter 1-2 is in a DC floating state inside the circuit of the second DC-DC converter 1-2. Since the first DC output terminal T21-2 is connected to the pulse output terminal T3-1 of the first inverter 2-1, the potential of the first DC output terminal T21-2 is the same as the potential of the pulse output terminal T3-1. Furthermore, the potential of the second DC output terminal T22-2 is increased from the potential of the first DC output terminal T21-2 to the second DC voltage V 2 The potential is the potential obtained by subtracting

[0043] As described later, in this embodiment, the potential of the pulse output terminal T3-1 is −10 kV or the ground potential 0 V, so the potential of the first DC output terminal T21-2 is also −10 kV or 0 V. Therefore, the potential of the second DC output terminal T22-2 is −11 kV or −1 kV. Therefore, the pulse power supply 100 according to this embodiment can output a pulse output voltage Vout of up to four levels.

[0044] The first inverter 2-1 is provided corresponding to the first DC-DC converter 1-1, and the second inverter 2-2 is provided corresponding to the second DC-DC converter 1-2.

[0045] The first inverter 2-1 has a pulse output terminal T3-1, a first switch 51-1, and a second switch 52-1. The pulse output terminal T3-1 of the first inverter 2-1 is connected to a first DC output terminal T21-2 of the second DC-DC converter 1-2.

[0046] The first switch 51-1 receives the first high control signal S 11 , the first switch 51-1 shorts or disconnects the first DC output terminal T21-1 and the pulse output terminal T3-1 in the first DC-DC converter 1-1. The first switch 51-1 is, for example, an enhancement type N-channel MOSFET. In this case, the drain of the first switch 51-1 is connected to the first DC output terminal T21-1, and the source is connected to the pulse output terminal T3-1. The first switch 51-1 has a gate connected to a first high control signal S 11 is given.

[0047] The second switch 52-1 receives the first low control signal S 12 In response to the first low control signal S, the second switch 52-1 shorts or disconnects the second DC output terminal T22-1 and the pulse output terminal T3-1 in the first DC-DC converter 1-1. The second switch 52-1 is, for example, an enhancement type N-channel MOSFET. In this case, the drain of the second switch 52-1 is connected to the pulse output terminal T3-1, and the source is connected to the second DC output terminal T22-1. The second switch 52-1 has a gate connected to the first low control signal S 12 is given.

[0048] The first switch 51-1 and the second switch 52-1 in the first inverter 2-1 perform complementary switching operations. That is, when the first switch 51-1 is in a short-circuited state, the second switch 52-1 is in a disconnected state. When the first switch 51-1 is in a disconnected state, the second switch 52-1 is in a short-circuited state.

[0049] As a result, the potential of the pulse output terminal T3-1 of the first inverter 2-1 becomes the reference potential when the first switch 51-1 is in a short-circuited state, and becomes the first DC voltage V 1 The potential at the pulse output terminal T3-1 of the first inverter 2-1 is determined. Therefore, the voltage output from the pulse output terminal T3-1 of the first inverter 2-1 (hereinafter, the first pulse output voltage) changes periodically due to the switching operations of the first switch 51-1 and the second switch 52-1. The potential at the pulse output terminal T3-1 of the first inverter 2-1 is also determined. Therefore, the potential at the first DC output terminal T21-2 in the second DC-DC converter 1-2 is also determined.

[0050] In this embodiment, since the potential difference between the first DC output terminal T21-1 and the second DC output terminal T22-1 in the first DC-DC converter 1-1 is −10 kV, a potential difference of 10 kV may occur between both ends of the first switch 51-1 and both ends of the second switch 52-1. Therefore, the potential difference may be shared by connecting multiple switches in series. For example, the first switch 51-1 and the second switch 52-1 may each be configured with five switches connected in series. Of course, not only the first switch 51-1 and the second switch 52-1 but also other switches may be configured with multiple switches connected in series.

[0051] The second inverter 2-2 has a pulse output terminal T3-2, a first switch 51-2, and a second switch 52-2. The pulse output terminal T3-2 of the second inverter 2-2 is connected to the load .

[0052] The first switch 51-2 receives the second high control signal S 21In response to this, the first switch 51-2 shorts or disconnects the first DC output terminal T21-2 and the pulse output terminal T3-2 in the second DC-DC converter 1-2. The first switch 51-2 is, for example, an enhancement type N-channel MOSFET. In this case, the drain of the first switch 51-2 is connected to the first DC output terminal T21-2, and the source is connected to the pulse output terminal T3-2. The first switch 51-2 has a gate connected to a second high control signal S 21 is given.

[0053] The second switch 52-2 receives the second low control signal S 22 In response to the second low control signal S, the second switch 52-2 shorts or disconnects the second DC output terminal T22-2 and the pulse output terminal T3-2 in the second DC-DC converter 1-2. The second switch 52-2 is, for example, an enhancement type N-channel MOSFET. In this case, the drain of the second switch 52-2 is connected to the pulse output terminal T3-2, and the source of the second switch 52-2 is connected to the second DC output terminal T22-2. The second switch 52-2 has a gate connected to a second low control signal S 22 is given.

[0054] The first switch 51-2 and the second switch 52-2 in the second inverter 2-2 perform complementary switching operations. That is, when the first switch 51-2 is in a short-circuited state, the second switch 52-2 is in a disconnected state. When the first switch 51-2 is in a disconnected state, the second switch 52-2 is in a short-circuited state.

[0055] As a result, the potential of the pulse output terminal T3-2 of the second inverter 2-2 becomes the same potential as the first DC output terminal T21-2 when the first switch 51-2 is short-circuited, and becomes the same potential as the second DC output terminal T22-2 when the second switch 52-2 is short-circuited. Therefore, the voltage output from the pulse output terminal T3-2 of the second inverter 2-2 (hereinafter, the second pulse output voltage) changes periodically due to the switching operations of the first switch 51-2 and the second switch 52-2. This second pulse output voltage is output to the load 70 as the pulse output voltage Vout.

[0056] The pulse control unit 3 is realized by a processing circuit such as a microcontroller. The pulse control unit 3 may be realized by a common circuit to the voltage control unit 40-1 of the first DC-DC converter 1-1 and the voltage control unit 40-2 of the second DC-DC converter 1-2.

[0057] The pulse control unit 3 controls the switching of the first inverter 2-1 and the second inverter 2-2. The pulse control unit 3 outputs a first high control signal S 11 and the first row control signal S 12 to the first inverter 2-1, and a second high control signal S 21 and the second low control signal S 22 is provided to the second inverter 2-2.

[0058] The pulse control unit 3 may control the duty ratio and switching period in any manner as long as it switches the first switch 51-1 and the second switch 52-1 included in the first inverter 2-1 complementarily. The same applies to the second inverter 2-2. The pulse control unit 3 may control the duty ratio and switching period of the first inverter 2-1 and the duty ratio and switching period of the second inverter 2-2 without any correlation with each other.

[0059] As described above, the first DC output terminal T21-2 of the second DC-DC converter 1-2 is in a DC floating state inside the circuit of the second DC-DC converter 1-2. Here, the first DC output terminal T21-2 of the second DC-DC converter 1-2 is connected to the pulse output terminal T3-1 of the first inverter 2-1. Furthermore, the first DC output terminal T21-1 of the first DC-DC converter 1-1 is connected to the reference potential. Therefore, the first DC output terminal T21-2 of the second DC-DC converter 1-2 becomes the reference potential when the first switch 51-1 of the first inverter 2-1 is in a short-circuit state. Therefore, the voltage control unit 40-2 of the second DC-DC converter 1-2 can detect the voltage of the second DC output terminal T22-2 at the timing when the first DC output terminal T21-2 becomes the reference potential based on the switching timing of the first inverter 2-1. For example, the voltage control unit 40-2 of the second DC-DC converter 1-2 outputs the first high control signal S 11 Based on the timing at which the first DC output terminal T21-2 becomes the reference potential, the second DC-DC converter 1-2 can detect the voltage of the second DC output terminal T22-2 at the timing at which the first DC output terminal T21-2 becomes the reference potential. As a result, the second DC-DC converter 1-2 outputs a stabilized second DC voltage V 2 can be generated.

[0060] If the pulse power supply device 100 is configured as described above, the first DC voltage V 1 potential difference, second DC voltage V 2 By adjusting the potential difference and the switching timing, a pulse output voltage Vout of multiple levels can be output at any timing.

[0061] Furthermore, as described above, the first DC output terminal T21-2 of the second DC-DC converter 1-2 is in a DC floating state inside the circuit of the second DC-DC converter 1-2. 2 This potential difference is not affected by the potential of the second DC output terminal T22-1 of the first DC-DC converter 1-1, which has a larger absolute value of the potential.

[0062] Therefore, what affects the withstand voltages of the first switch 51-2 and the second switch 52-2 included in the second inverter 2-2 is the potential difference between the first DC output terminal T21-2 and the second DC output terminal T22-2 (the second DC voltage V 2 ).

[0063] Therefore, the first DC voltage V 1 The absolute value of the second DC voltage V 2 Even if the absolute value of the second DC voltage V 2 This can be realized by an element having a withstand voltage sufficient to switch the pulsed output voltage Vout at multiple levels at any desired timing simply and at low cost.

[0064] 2 shows a first example of a simulation waveform of the pulse power supply 100 according to the first embodiment. 11 (B) shows an example of the waveform of the first row control signal S 12 (C) shows an example of the waveform of the second high control signal S 21 (D) shows an example of the waveform of the second row control signal S 22 An example of the waveform is shown below.

[0065] In this embodiment, the first high control signal S 11 , the first row control signal S 12 , the second high control signal S 21 and the second low control signal S 22 The duration of one period is 2.5 μs. Therefore, the pulse frequency of the pulse output voltage Vout is 400 kHz.

[0066] (E) shows the first pulse output voltage output from the first inverter 2-1 when the first inverter 2-1 is directly connected to the load 70. In the case of FIG. 2, the first pulse output voltage is 11When the logic level is H, the first low control signal S 12 When the logic is H, the first DC voltage V 1 (-10kV).

[0067] (F) shows the second pulse output voltage when the second inverter 2-2 is directly connected to the load 70, that is, when it is assumed that the first DC output terminal T21-2 of the second DC-DC converter 1-2 is not connected to the pulse output terminal T3-1 of the first inverter 2-1 and the first DC output terminal T21-2 of the second DC-DC converter 1-2 is connected to the reference potential. That is, it shows the potential of the pulse output terminal T3-2 of the second inverter 2-2. In the case of FIG. 2, the second pulse output voltage is the second high control signal S 21 When the logic level is H, the second low control signal S 22 is -1kV when the logic is H.

[0068] (G) shows the pulse output voltage Vout. The pulse power supply 100 outputs a pulse output voltage Vout obtained by adding together the first pulse output voltage shown in (E) and the second pulse output voltage shown in (F). In the case of FIG. 2, the pulse power supply 100 can output a pulse output voltage Vout that repeats 0V, -10kV, -11kV, and -10kV as shown in (G). In this way, the pulse power supply 100 can output a pulse output voltage Vout that repeats 0V, -10kV, -11kV, and -10kV as shown in (G). 1 , second DC voltage V 2 Furthermore, by controlling the switching timing of the first inverter 2-1 and the second inverter 2-2, it is possible to output a pulse output voltage Vout at multiple levels at any desired timing.

[0069] Fig. 3 shows a second example of simulation waveforms of the pulse power supply 100 according to the first embodiment. (A) to (F) of Fig. 3 show the same signals and voltages as (A) to (F) of Fig. 2. In the case of Fig. 3, the pulse power supply 100 can output a pulse output voltage Vout that repeats -10 kV, 0 V, -1 kV, and 0 V, as shown in (G).

[0070] Fig. 4 shows a third example of simulation waveforms of the pulse power supply 100 according to the first embodiment. (A) to (F) of Fig. 4 show the same signals and voltages as (A) to (F) of Fig. 2. In the case of Fig. 4, the pulse power supply 100 can output a pulse output voltage Vout that repeats 0 kV, -1 kV, -11 kV, and -10 kV, as shown in (G).

[0071] Fig. 5 shows a fourth example of a simulation waveform of the pulse power supply 100 according to the first embodiment. (A) to (F) of Fig. 5 show the same signals and voltages as (A) to (F) of Fig. 2. In the case of Fig. 5, the pulse power supply 100 can output a pulse output voltage Vout that repeats -10 kV, -1 kV, 0 V, and -11 kV, as shown in (G). In this way, the pulse power supply 100 can output a pulse output voltage Vout of multiple levels at any timing.

[0072] 6 shows the configuration of a pulse power supply 200 according to the second embodiment, together with a load 70. The pulse power supply 200 according to the second embodiment has substantially the same functions and configuration as the pulse power supply 100 according to the first embodiment, and includes substantially the same circuits as those included in the pulse power supply 100. Circuits that are the same as those included in the pulse power supply 100 according to the first embodiment are given the same reference numerals, and detailed explanations thereof will be omitted.

[0073] The pulse power supply device 200 according to the second embodiment includes N DC-DC converters 1 (N is an integer of 2 or more), N inverters 2, and a pulse control unit 3.

[0074] Each of the N DC-DC converters 1 is a switching power supply device including a rectifier circuit that rectifies voltage using a rectifier element in a stage subsequent to a switch circuit for power conversion. The N DC-DC converters 1 are composed of a first DC-DC converter 1-1 to an N-th DC-DC converter 1-N. The first DC-DC converter 1-1 and the second DC-DC converter 1-2 have the same configuration as in the first embodiment.

[0075] In this embodiment, the nth DC-DC converter 1-n (n is an integer of 3 or more and N or less) is an isolated switching power supply device having the same configuration as the second DC-DC converter 1-2, but the potential difference between the first DC output terminal T21-n and the second DC output terminal T22-n in each DC-DC converter 1 may be different for each DC-DC converter 1. In the description of the second embodiment, the nth first DC input terminal is the first DC input terminal T11-n, the nth second DC input terminal is the second DC input terminal T12-n, the nth first DC output terminal is the first DC output terminal T21-n, and the nth second DC output terminal is the second DC output terminal T22-n.

[0076] The n-th DC-DC converter 1-n includes a first DC input terminal T11-n, a second DC input terminal T12-n, a first DC output terminal T21-n, and a second DC output terminal T22-n. In the n-th DC-DC converter 1-n, an input voltage Vin is supplied between the first DC input terminal T11-n and the second DC input terminal T12-n. The second DC input terminal T12-n is connected to a reference potential. The n-th DC-DC converter 1-n converts the supplied input voltage Vin into a desired potential difference V n and output it between the first DC output terminal T21-n and the second DC output terminal T22-n. Thereafter, the voltage of the first DC output terminal T21-n with respect to the second DC output terminal T22-n is converted into the n-th DC voltage V n The potential of the first DC output terminal T21-n is higher than the potential of the second DC output terminal T22-n.

[0077] Moreover, the first DC output terminal T21-n of the n-th DC-DC converter 1-n is in a DC floating state inside the circuit of the n-th DC-DC converter 1-n. Moreover, since the first DC output terminal T21-n is connected to the pulse output terminal T3-(n-1) of the (n-1)th inverter 2-(n-1), the potential of the first DC output terminal T21-n becomes the same potential as the potential of the pulse output terminal T3-(n-1). Moreover, the potential of the second DC output terminal T22-n is changed from the potential of the first DC output terminal T21-n to the n-th DC voltage V nThe potential is the potential obtained by subtracting

[0078] In this embodiment, the DC voltage generated in any one of the second DC-DC converter 1-2 to the N-th DC-DC converter 1-N (second DC voltage V 2 ~Nth DC voltage V N ) is the absolute value of the first DC voltage V generated by the first DC-DC converter 1-1. 1 is less than or equal to the absolute value of

[0079] The N inverters 2 are provided in one-to-one correspondence with the N DC-DC converters 1. The N inverters 2 are composed of a first inverter 2-1 to an N-th inverter 2-N. Of the N inverters 2, the first inverter 2-1 corresponds to the first DC-DC converter 1-1. Of the N inverters 2, the n-th inverter 2-n corresponds to the n-th DC-DC converter 1-n. The first inverter 2-1 and the second inverter 2-2 are the same as those in the first embodiment. However, the load 70 is connected to the pulse output terminal T3-N of the N-th inverter 2-N.

[0080] The n-th inverter 2-n has a pulse output terminal T3-n, a first switch 51-n, and a second switch 52-n.

[0081] The pulse output terminal T3-m of the m-th inverter 2-m (m is 2 or more and N-1 or less) of the N inverters 2 is connected to the first DC output terminal T21-(m+1) of the (m+1)-th DC-DC converter 1-(m+1). That is, the first DC output terminal T21-n of the n-th DC-DC converter 1-n is connected to the pulse output terminal T3-(n-1) of the (n-1)-th inverter 2-(n-1) of the N inverters 2. The pulse output terminal T3-N of the N-th inverter 2-N is connected to the load 70.

[0082] The first switch 51-n receives the n-th high control signal S n1In response to this, the first switch 51-n shorts or disconnects the first DC output terminal T21-n and the pulse output terminal T3-n in the n-th DC-DC converter 1-n. The first switch 51-n is, for example, an enhancement-type N-channel MOSFET. In this case, the drain of the first switch 51-n is connected to the first DC output terminal T21-n, and the source is connected to the pulse output terminal T3-n. The first switch 51-n receives the n-th high control signal S n1 is given.

[0083] The second switch 52-n receives the n-th row control signal S n2 In response to the n-th low control signal S, the second switch 52-n shorts or disconnects the second DC output terminal T22-n and the pulse output terminal T3-n in the n-th DC-DC converter 1-n. The second switch 52-n is, for example, an enhancement type N-channel MOSFET. In this case, the drain of the second switch 52-n is connected to the pulse output terminal T3-n, and the source of the second switch 52-n is connected to the second DC output terminal T22-n. The second switch 52-n receives the n-th low control signal S n2 The first switch 51-n and the second switch 52-n in the n-th inverter 2-n perform a switching operation in a complementary manner.

[0084] The pulse control unit 3 controls the switching of each of the N inverters 2. The pulse control unit 3 outputs a first high control signal S 11 and the first row control signal S 12 to the first inverter 2-1. The pulse control unit 3 outputs the n-th high control signal S n1 and the nth row control signal S n2 is provided to the nth inverter 2-n.

[0085] The pulse control unit 3 may control the duty ratio and switching period in any manner as long as it switches the first switch 51-1 and the second switch 52-1 included in the first inverter 2-1 complementarily. The same applies to the n-th inverter 2-n. The pulse control unit 3 may control the switching duty ratio and switching period of each of the N inverters 2 without any correlation with each other.

[0086] Here, the potential of the pulse output terminal T3-1 of the first inverter 2-1 is determined whether the first switch 51-1 is short-circuited or the second switch 52-1 is short-circuited. Therefore, the potential of the first DC output terminal T21-2 of the second DC-DC converter 1-2 is also determined. Therefore, the potential of the pulse output terminal T3-2 of the second inverter 2-2 is also determined. Similarly, the potential of the first DC output terminal T21-n of the n-th DC-DC converter 1-n is also determined. In addition, the potential of the pulse output terminal T3-n of the n-th inverter 2-n is also determined. Therefore, the potential of the pulse output terminal T3-N of the N-th inverter 2-N is also determined.

[0087] Therefore, the first DC output terminal T21-n of the n-th DC-DC converter 1-n becomes the reference potential when the first switch 51-1 of the first inverter 2-1 is in a short-circuit state and all the first switches 51-2 to 51-(n-1) from the second inverter 2-2 to the (n-1)th inverter 2-(n-1) are in a short-circuit state. Therefore, the n-th DC-DC converter 1-n can detect the voltage of the second DC output terminal T22-n at the timing when the first DC output terminal T21-n becomes the reference potential based on the switching timing of the first inverter 2-1 to the (n-1)th inverter 2-(n-1). As a result, the n-th DC-DC converter 1-n can detect the voltage of the second DC output terminal T22-n at the timing when the first DC output terminal T21-n becomes the reference potential between the first DC output terminal T21-n and the second DC output terminal T22-n. n can be generated.

[0088] If the pulse power supply device 200 is configured as described above, the first DC voltage V 1 ~Nth DC voltage VN By adjusting the switching timing, a pulse output voltage Vout of multiple levels can be output at any desired timing.

[0089] Furthermore, the first DC output terminal T21-n (n is 2 or more and N or less) of the n-th DC-DC converter 1-n is in a DC floating state inside the circuit of the n-th DC-DC converter 1-n.

[0090] Therefore, the n-th DC voltage V generated in the n-th DC-DC converter 1-n n Even if the n-th inverter 2-n has a large voltage (for example, about 10 kV), it does not affect the withstand voltage of the first switch 51 and the second switch 52 included in the inverters other than the corresponding inverter. In other words, the withstand voltage of the first switch 51-n and the second switch 52-n included in the n-th inverter 2-n is determined based on the potential difference (n-th DC voltage V n ) may be determined accordingly.

[0091] For example, when N=3, the first DC voltage V of the first DC-DC converter 1-1 is 1 is 10 kV, the second DC voltage V of the second DC-DC converter 1-2 2 is 1 kV, and the third DC voltage V of the third DC-DC converter 1-3 3 If is 1kV, the first DC voltage V 1 becomes the maximum value of 10 kV, and the second DC voltage V 2 and the third DC voltage V 3 However, the absolute value is larger than the first DC voltage V 1 does not affect the withstand voltages of the first switch 51-2 and the second switch 52-2 included in the second inverter 2-2 and the first switch 51-3 and the second switch 52-3 included in the third inverter 2-3.

[0092] Therefore, the largest nth DC voltage V nThe switch included in each inverter 2 can be realized by an element having a withstand voltage sufficient to switch in response to the potential difference between the first DC output terminal T21 and the second DC output terminal T22 of the corresponding DC-DC converter 1. This enables the pulse power supply device 200 to output the pulse output voltage Vout simply and at low cost.

[0093] 7 shows simulation waveforms of the pulse power supply 200 according to the second embodiment. FIG. 7 shows the case where N=3. (A) shows the first high control signal S 11 (B) shows an example of the waveform of the second high control signal S 21 (C) shows an example of the waveform of the third high control signal S 31 An example of the waveform is shown below.

[0094] (D) shows the first pulse output voltage output from the first inverter 2-1 when the first inverter 2-1 is directly connected to the load 70. In the case of FIG. 7, the first pulse output voltage is 11 When the logic level is H, the first low control signal S 12 When the logic is H, the first DC voltage V 1 (-10kV).

[0095] (E) shows the second pulse output voltage when the second inverter 2-2 is directly connected to the load 70, that is, when it is assumed that the first DC output terminal T21-2 of the second DC-DC converter 1-2 is not connected to the pulse output terminal T3-1 of the first inverter 2-1 and the first DC output terminal T21-2 of the second DC-DC converter 1-2 is connected to the reference potential. That is, it shows the potential of the pulse output terminal T3-2 of the second inverter 2-2. In the case of FIG. 7, the second pulse output voltage is the second high control signal S 21 When the logic level is H, the second low control signal S 22 When the logic is H, it becomes -1kV.

[0096] (F) shows the third pulse output voltage when the third inverter 2-3 is directly connected to the load 70, that is, when it is assumed that the first DC output terminal T21-3 of the third DC-DC converter 1-3 is not connected to the pulse output terminal T3-2 of the second inverter 2-2 and the first DC output terminal T21-3 of the third DC-DC converter 1-3 is connected to the reference potential. That is, it shows the potential of the pulse output terminal T3-3 of the third inverter 2-3. In the case of FIG. 7, the third pulse output voltage is the third high control signal S 31 When the logic level is H, the third low control signal S 32 When the logic is H, the third DC voltage V 3 (-1kV).

[0097] (G) shows the pulse output voltage Vout. The pulse power supply 200 outputs a pulse output voltage Vout obtained by adding together the first pulse output voltage shown in (D), the second pulse output voltage shown in (E), and the third pulse output voltage shown in (F). In the case of FIG. 7, the pulse power supply 200 can output a pulse output voltage Vout that repeats -11 kV, -10 kV, 0 V, -1 kV, 0 V, and -10 kV as shown in (G). In this way, the pulse power supply 200 can output a pulse output voltage Vout that repeats -11 kV, -10 kV, 0 V, -10 kV, as shown in (G). 1 , second DC voltage V 2 , the third DC voltage V 3 In addition, by controlling the switching timing of the first inverter 2-1 to the third inverter 2-3, a pulse output voltage Vout of multiple levels can be output at any timing.

[0098] 8 shows the configuration of a pulse power supply 300 according to the third embodiment, together with a load 70. The pulse power supply 300 according to the third embodiment has substantially the same functions and configuration as the pulse power supply 100 according to the first embodiment, and includes substantially the same circuits as those included in the pulse power supply 100. Circuits that are the same as those included in the pulse power supply 100 according to the first embodiment are given the same reference numerals, and detailed explanations thereof will be omitted.

[0099] In the pulse power supply 100 according to the first embodiment, the first DC-DC converter 1-1 has a first DC output terminal T21-1 connected to the reference potential. In contrast, in the pulse power supply 300 according to the third embodiment, the second DC output terminal T22-1 in the first DC-DC converter 1-1 is connected to the reference potential.

[0100] In the pulse power supply device 100 according to the first embodiment, the voltage control unit 40-2 of the second DC-DC converter 1-2 controls the switching timing of the first inverter 2-1 (the first high control signal S 11 The voltage of the second DC output terminal T22-2 at the timing when the first DC output terminal T21-2 becomes the reference potential is detected based on the timing of the first DC output terminal T21-2 becoming the reference potential. 2 In contrast, in the pulse power supply device 300 according to the third embodiment, the voltage control section 40-2 of the second DC-DC converter 1-2 controls the switching timing of the first inverter 2-1 (the first low control signal S 12 The voltage of the second DC output terminal T22-2 at the timing when the second DC output terminal T22-2 becomes the reference potential is detected based on the timing of the first DC output terminal T21-2 and the second DC output terminal T22-2 being stabilized. 2 The control is performed to generate the

[0101] Except for these differences, the first DC-DC converter 1-1 and the pulse power supply 300 according to the third embodiment have the same configuration. Therefore, the first DC-DC converter 1-1 in the pulse power supply 300 according to the third embodiment outputs a first DC voltage V 1 A potential difference of +1 can be generated, and a positive voltage can be output to the first DC output terminal T21-1.

[0102] 9 shows an example of a simulation waveform of the pulse power supply 300 according to the third embodiment.11 (B) shows an example of the waveform of the first row control signal S 12 (C) shows an example of the waveform of the second high control signal S 21 (D) shows an example of the waveform of the second row control signal S 22 An example of the waveform is shown below.

[0103] In this embodiment, the first high control signal S 11 , the first row control signal S 12 , the second high control signal S 21 and the second low control signal S 22 The duration of one period is 2.5 μs. Therefore, the pulse frequency of the pulse output voltage Vout is 400 kHz.

[0104] (E) shows the first pulse output voltage output from the first inverter 2-1 when the first inverter 2-1 is directly connected to the load 70. In the case of FIG. 9, the first pulse output voltage is 11 When the logic is H, the first DC voltage V 1 (10kV), and the first low control signal S 12 When the logic level is H, the voltage becomes 0V.

[0105] (F) shows the second pulse output voltage when the second inverter 2-2 is directly connected to the load 70, that is, when it is assumed that the first DC output terminal T21-2 of the second DC-DC converter 1-2 is not connected to the pulse output terminal T3-1 of the first inverter 2-1 and the first DC output terminal T21-2 of the second DC-DC converter 1-2 is connected to the reference potential. That is, it shows the potential of the pulse output terminal T3-2 of the second inverter 2-2. In the case of FIG. 9, the second pulse output voltage is the second high control signal S 21 When the logic level is H, the second low control signal S 22 is -1kV when the logic is H.

[0106] (G) shows the pulse output voltage Vout. The pulse power supply 300 outputs a pulse output voltage Vout obtained by adding together the first pulse output voltage shown in (E) and the second pulse output voltage shown in (F). In the case of FIG. 9, the pulse power supply 300 can output a pulse output voltage Vout that repeats 10 kV, 0 V, -1 kV, and 0 V, as shown in (G). In this way, the pulse power supply 300 can output a pulse output voltage Vout that repeats 10 kV, 0 V, -1 kV, and 0 V. 1 , second DC voltage V 2 Furthermore, by controlling the switching timing of the first inverter 2-1 and the second inverter 2-2, it is possible to output a pulse output voltage Vout at multiple levels at any desired timing.

[0107] For example, in the same manner as in the pulse power supply device 100 according to the first embodiment shown in FIGS. 3 to 5, the first DC voltage V 1 , second DC voltage V 2 Furthermore, by controlling the switching timing of the first inverter 2-1 and the second inverter 2-2, it is possible to output a pulse output voltage Vout at multiple levels at any desired timing.

[0108] Also, similar to the pulse power supply device 200 according to the second embodiment shown in FIG. 6, it is possible to have N (N is an integer of 2 or more) DC-DC converters 1, N inverters 2, and a pulse control unit 3. That is, the first DC-DC converter 1-1 shown in FIG. 6 can be configured as the first DC-DC converter 1-1 shown in FIG. 8. In this case, for example, if N=3 as in FIG. 7, the first DC voltage V 1 , second DC voltage V 2 , the third DC voltage V 3 In addition, by controlling the switching timing of the first inverter 2-1 to the third inverter 2-3, a pulse output voltage Vout of multiple levels can be output at any timing.

[0109] Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. Various modifications can be made to the embodiments. [Explanation of symbols]

[0110] 100 Pulse power supply device, 200 Pulse power supply device, 70 Load, 1-1 First DC-DC converter, 1-2 Second DC-DC converter, 1-n nth DC-DC converter, 2-1 First inverter, 2-2 Second inverter, 2-n nth inverter, 3 Pulse control unit, T11-1 First DC input terminal in the first DC-DC converter, T12-1 Second DC input terminal in the first DC-DC converter, T11-n First DC input terminal in the nth DC-DC converter, T12-n Second DC input terminal in the nth DC-DC converter, T21-1 First DC output terminal in the first DC-DC converter, T22-1 Second DC output terminal in the first DC-DC converter, T21-n First DC output terminal in the nth DC-DC converter, T22-n Second DC output terminal in the nth DC-DC converter

Claims

1. N (N is an integer of 2 or more) DC-DC converters each having a DC input section consisting of a first DC input terminal and a second DC input terminal and a DC output section consisting of a first DC output terminal and a second DC output terminal, transforming a DC voltage input between the first DC input terminal and the second DC input terminal, and generating a transformed DC voltage between the first DC output terminal and the second DC output terminal; N inverters, each having a switch and a pulse output terminal, provided in one-to-one correspondence with the N DC-DC converters; Equipped with each of the N inverters includes a first switch which shorts or disconnects the first DC output terminal and the pulse output terminal in a corresponding DC-DC converter among the N DC-DC converters, and a second switch which shorts or disconnects the second DC output terminal and the pulse output terminal in the corresponding DC-DC converter, and is configured to output a pulse output voltage from the pulse output terminal by complementary switching operations of the first switch and the second switch; a first DC-DC converter of the N DC-DC converters has an isolation transformer for transforming a voltage between the DC input unit and the DC output unit, and the first DC output terminal or the second DC output terminal is connected to a reference potential; a pulse output terminal of an Nth DC-DC converter among the N DC-DC converters is connected to a load; The first DC output terminal of the nth (n is an integer of 2 or more and N or less) DC-DC converter is connected to the pulse output terminal of the (n-1)th inverter of the N inverters. Pulse power supply.

2. A pulse control unit controls a switching timing of the switch in each of the N inverters, Each of the N DC-DC converters is a switching power supply device, Each of the nth DC-DC converters detects a voltage of the second DC output terminal at a timing when the first DC output terminal becomes the reference potential, and stabilizes a DC voltage generated between the first DC output terminal and the second DC output terminal based on the detected voltage of the second DC output terminal.

2. The pulse power supply of claim 1.

3. The absolute value of the potential difference between the first DC output terminal and the second DC output terminal of the first DC-DC converter is greater than the absolute value of the potential difference between the first DC output terminal and the second DC output terminal of a second DC-DC converter among the N DC-DC converters.

3. A pulse power supply according to claim 1 or 2.

4. The absolute value of the potential difference between the first DC output terminal and the second DC output terminal in the first DC-DC converter is larger than the maximum absolute value of the potential difference between the first DC output terminal and the second DC output terminal in second to Nth (N is an integer of 3 or more) DC-DC converters among the N DC-DC converters.

3. A pulse power supply according to claim 1 or 2.

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