Boost rectifier circuit

Abstract

The objective is to provide a boost rectifier circuit that has a simple structure and can suppress ripple voltage. [Solution] The boost rectifier circuit 1 includes a transformer 21 that inputs an AC voltage to the primary winding 21a, a full-wave rectifier circuit section 3 that generates a first DC voltage VDC1 by rectifying the AC voltage generated in the secondary winding 21b, a first half-wave rectifier type CW circuit section 7, and a second half-wave rectifier type CW circuit section 8. The first half-wave rectifier type CW circuit section 7 rectifies and boosts the AC voltage generated in the secondary winding 2b, and the second half-wave rectifier type CW circuit section 8 rectifies and boosts the AC voltage generated in the secondary winding 2b in the opposite phase to the first half-wave rectifier type CW circuit section 7. The output voltage from the first half-wave rectifier type CW circuit section 7 and the output voltage from the second half-wave rectifier type CW circuit section 8 are added to the first DC voltage VDC1 in the first series circuit section 4 to generate a second DC voltage VDC2.

Description

Technical Field

[0001] The present disclosure relates to a step-up rectifier circuit.

Background Art

[0002] There is known a step-up rectifier circuit including a Cockcroft-Walton circuit (hereinafter, CW circuit) that boosts and rectifies an input voltage by combining a plurality of circuit portions including capacitors and diodes (see, for example, Patent Document 1). The CW circuit has a half-wave rectification method and a full-wave rectification method.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] [[ID=३५]]The CW circuit of the half-wave rectification method generates a high voltage using only one half-wave of the AC voltage generated in the secondary winding of the transformer. The CW circuit of the half-wave rectification method has fewer components and a simpler circuit configuration, but is less efficient than the full-wave rectification method, and ripple noise and AC noise are likely to be superimposed on the output voltage. The CW circuit of the full-wave rectification method generates a high voltage using both half-waves of the AC voltage generated in the secondary winding of the transformer. The CW circuit of the full-wave rectification method is more efficient than the half-wave rectification method and ripple noise and AC noise are less likely to be superimposed on the output voltage, but has more components and a more complicated circuit configuration.

[0005] An object of the present disclosure is to provide a step-up rectifier circuit having a simple structure and capable of suppressing a ripple voltage.

Means for Solving the Problems

[0006] A step-up rectifier circuit relating to one aspect of the present disclosure includes: [1] a transformer including a primary winding and a secondary winding, to which an AC voltage is input to the primary winding; a full-wave rectifier circuit section connected to the secondary winding and which generates a first DC voltage by rectifying the AC voltage generated in the secondary winding; a first series circuit section consisting of a plurality of first capacitors and a plurality of second capacitors connected alternately in series; a second series circuit section consisting of a plurality of third capacitors connected in series; and a third series circuit section consisting of a plurality of fourth capacitors connected in series, wherein one end of the second series circuit section is connected to one end of the secondary winding, one end of the third series circuit section is connected to the other end of the secondary winding, and one end of the first series circuit section is connected to the output terminal of the full-wave rectifier circuit section. The third capacitor in the series circuit section and the first capacitor in the first series circuit section constitute a first half-wave rectifier type boost circuit section, the fourth capacitor in the third series circuit section and the second capacitor in the first series circuit section constitute a second half-wave rectifier type boost circuit section, the first half-wave rectifier type boost circuit section rectifies and boosts the AC voltage generated in the secondary winding, the second half-wave rectifier type boost circuit section rectifies and boosts the AC voltage generated in the secondary winding in the opposite phase to the first half-wave rectifier type boost circuit section, and the output voltage from the first half-wave rectifier type boost circuit section and the output voltage from the second half-wave rectifier type CW circuit section are added to the first DC voltage in the first series circuit section to generate a second DC voltage, thus creating a boost rectifier circuit.

[0007] In the boost rectifier circuit described in [1] above, by placing the full-wave rectifier circuit immediately after the transformer, it is possible to generate a first DC voltage while suppressing ripple by utilizing both half-waves of the AC voltage generated in the secondary winding of the transformer. Furthermore, in the half-wave rectifier boost circuit, which has fewer components than the full-wave rectifier boost circuit, the phase of the output voltage from the first half-wave rectifier boost circuit and the phase of the output voltage from the second half-wave rectifier boost circuit are in opposite phases, so the noise superimposed on the first series circuit cancels each other out. As a result, it is possible to generate a second DC voltage while effectively suppressing ripple. In addition, the boost rectifier circuit described in [1] does not require the use of two transformers or a transformer with a center tap, as is the case with the full-wave rectifier boost circuit. Therefore, by combining the full-wave rectifier circuit and the half-wave rectifier CW circuit, a simple structure is achieved while suppressing ripple voltage.

[0008] A boost rectifier circuit relating to one aspect of the present disclosure includes: [2] "The full-wave rectifier circuit section includes a first rectifier capacitor, a second rectifier capacitor, a third rectifier capacitor, a first diode, a second diode, a third diode, and a fourth diode, wherein the anode of the first diode is connected to one electrode of the first rectifier capacitor, the cathode of the first diode is connected to one electrode of the second rectifier capacitor, the anode of the second diode is connected to one electrode of the second rectifier capacitor, the cathode of the second diode is connected to one end of the secondary winding, and the third diode The anode of the diode is connected to one electrode of the first rectifier capacitor, the cathode of the third diode is connected to one electrode of the third rectifier capacitor, the anode of the fourth diode is connected to one electrode of the third rectifier capacitor, the cathode of the fourth diode is connected to the other end of the secondary winding, the other electrode of the first rectifier capacitor is connected to a reference potential line, the other electrode of the second rectifier capacitor is connected to the other end of the secondary winding, and the other electrode of the third rectifier capacitor is connected to one end of the secondary winding, which may be the boost rectifier circuit described in [1]. In this case, the amount of charge stored in the first capacitor is increased by utilizing the positive and negative half-waves of the AC voltage generated in the secondary winding, and the boost ratio can be increased in the full-wave rectifier circuit section.

[0009] A boost rectifier circuit relating to one aspect of the present disclosure is described as follows: [3] "The full-wave rectifier circuit section includes a first rectifier capacitor, a first diode, a second diode, a third diode, and a fourth diode, wherein the anode of the first diode is connected to one electrode of the first rectifier capacitor, the cathode of the first diode is connected to one end of the secondary winding, the anode of the second diode is connected to one end of the secondary winding, and the cathode of the second diode is connected to the first rectifier capacitor The high-voltage power supply described in [1] or [2] may be the one described in [1] or [2], wherein the anode of the third diode is connected to the other electrode of the rectifier, the anode of the third diode is connected to one electrode of the first rectifier capacitor, the cathode of the third diode is connected to the other end of the secondary winding, the anode of the fourth diode is connected to the other end of the secondary winding, the cathode of the fourth diode is connected to the other electrode of the first rectifier capacitor, and the other electrode of the first rectifier capacitor is connected to a reference potential line. In this case, the full-wave rectifier circuit section also has a simple configuration with fewer components, making it easier to further reduce the number of components in the boost rectifier circuit. [Effects of the Invention]

[0010] According to this disclosure, it is possible to provide a boost rectifier circuit that has a simple structure and can suppress ripple voltage. [Brief explanation of the drawing]

[0011] [Figure 1] This is a circuit diagram showing the configuration of a boost rectifier circuit according to one embodiment of the present disclosure. [Figure 2] This is a circuit diagram showing the configuration of a boost rectifier circuit according to the second embodiment. [Figure 3] This is a circuit diagram showing the configuration of a boost rectifier circuit according to the third embodiment. [Figure 4] This is a circuit diagram showing the configuration of the boost rectifier circuit related to the first comparative example. [Figure 5] This is a circuit diagram showing the configuration of a boost rectifier circuit relating to the second comparative example. [Figure 6]Figure 6(a) shows an example of the ripple voltage superimposed on the second DC voltage generated by the boost rectifier circuit according to the second embodiment, the boost rectifier circuit according to the first comparative example, and the boost rectifier circuit according to the second comparative example. Figure 6(b) shows an example of comparing the ripple voltage, number of components, and output voltage rise time for the boost rectifier circuit according to the second embodiment, the boost rectifier circuit according to the first comparative example, and the boost rectifier circuit according to the second comparative example. [Figure 7] This is a circuit diagram showing the configuration of a boost rectifier circuit according to the first modified example. [Figure 8] This is a circuit diagram showing the configuration of a boost rectifier circuit according to the second modified example. [Modes for carrying out the invention]

[0012] Hereinafter, preferred embodiments of a boost rectifier circuit according to one embodiment of the present disclosure will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[0013] [First Embodiment] Figure 1 is a circuit diagram showing the configuration of a boost rectifier circuit according to one embodiment of the present disclosure. As shown in Figure 1, the boost rectifier circuit 1 according to the present embodiment includes a DC power supply 11, an H-bridge circuit 12, a transformer 21, a diode 22, a diode 23, a full-wave rectifier circuit section 3, a first series circuit section 4, a second series circuit section 5, and a third series circuit section 6.

[0014] The DC power supply 11 outputs a DC voltage. One end of the DC power supply 11 is connected to the reference potential line (also called the ground potential line or earth potential line) GND, and the other end is connected to the input terminal of the H-bridge circuit 12. One output terminal 12a of the H-bridge circuit 12 is connected to one end of the primary winding 21a of the transformer 21 via a resistor 13a, a capacitor 14a, and an inductor 15a. The other output terminal 12b of the H-bridge circuit 12 is connected to the other end of the primary winding 21a of the transformer 21. The two ends of the primary winding 21a are connected to each other via an inductor 15b and a capacitor 14b, which are provided in parallel with each other.

[0015] In the circuit described above, when a DC voltage is output from the DC power supply 11, this DC voltage is periodically distributed to two output terminals 12a and 12b by the H-bridge circuit 12. That is, square waves with opposite phases are output from the two output terminals 12a and 12b. These square waves are converted into AC voltages by the resistor, inductor, and capacitor described above, and this AC voltage is input to the primary winding 21a of the transformer 21. Note that other circuits (such as a push-pull circuit) may be used instead of the H-bridge circuit 12, as long as they can apply an AC voltage to the primary winding 21a of the transformer 21.

[0016] The anode of diode 22 is connected to one end 21c of the secondary winding 21b. The cathode of diode 22 is connected to the reference potential line GND. The anode of diode 23 is connected to the other end 21d of the secondary winding 21b. The cathode of diode 23 is connected to the reference potential line GND.

[0017] The full-wave rectifier circuit section 3 is connected to both ends of the secondary winding 21b. The full-wave rectifier circuit section 3 includes a capacitor 31 (first rectifier capacitor), a capacitor 32 (second rectifier capacitor), a capacitor 33 (third rectifier capacitor), a diode 34 (first diode), a diode 35 (second diode), a diode 36 (third diode), and a diode 37 (fourth diode). In the following description, one electrode of the capacitor mainly refers to the electrode located on the output side, that is, the side opposite to the secondary winding 21b. The other electrode of the capacitor mainly refers to the electrode located on the input side, that is, the side of the secondary winding 21b.

[0018] The anode of the diode 34 is connected to one electrode of the capacitor 31, and the cathode of the diode 34 is connected to one electrode of the capacitor 32. The anode of the diode 35 is connected to one electrode of the capacitor 32, and the cathode of the diode 35 is connected to one end 21c of the secondary winding 21b. The anode of the diode 36 is connected to one electrode of the capacitor 31, and the cathode of the diode 36 is connected to one electrode of the capacitor 33. The anode of the diode 37 is connected to one electrode of the capacitor 33, and the cathode of the diode 37 is connected to the other end 21d of the secondary winding 21b. The other electrode of the capacitor 31 is connected to the reference potential line GND. The other electrode of the capacitor 32 is connected to the other end 21d of the secondary winding 21b. The other electrode of the capacitor 33 is connected to one end 21c of the secondary winding 21b.

[0019] The full-wave rectifier circuit section 3 generates a first DC voltage VDC1 by rectifying the AC voltage generated in the secondary winding 21b. In the full-wave rectifier circuit section 3 according to the present embodiment, a first DC voltage VDC1 obtained by rectifying and boosting the AC voltage in the secondary winding 21b is output from the output terminal of the full-wave rectifier circuit section 3, that is, one electrode of the capacitor 31. The full-wave rectifier circuit section 3, for example, increases the amount of charge stored in the capacitor 31 by utilizing the positive and negative half-waves of the AC voltage in the secondary winding 21b to generate the first DC voltage VDC1. As an example, when the DC power supply 11 generates a voltage of 50V and the turns ratio of the transformer 21 is 1 to 100, the amplitude value of the AC voltage in the secondary winding 21b can be 5 kVp-p. In this case, the full-wave rectifier circuit section 3 generates a first DC voltage VDC1 with an absolute value of 10 kV.

[0020] The first series circuit section 4 is formed by alternately connecting a plurality of first capacitors and a plurality of second capacitors in series. In the example of FIG. 1, the first series circuit section 4 includes N (N is an integer of 2 or more; the case of N = 3 is illustrated in the figure) first capacitors Cp(2), Cp(4),..., Cp(ZN), and N second capacitors Cq(2), Cq(4),..., Cq(2N) alternately connected in series. One end of the first series circuit section 4 is connected to the output terminal of the full-wave rectifier circuit section 3. Specifically, one end of the first series circuit section 4 is connected to one electrode of the capacitor 31. The second series circuit section 5 is formed by connecting a plurality of third capacitors in series. In the example of FIG. 1, the second series circuit section 5 includes N third capacitors Cp(1), Cp(3),..., Cp(2N - 1) connected in series. One end of the second series circuit section 5 is connected to one end 21c of the secondary winding 21b. The third series circuit section 6 is formed by connecting a plurality of fourth capacitors in series. In the example of FIG. 1, the third series circuit section 6 includes N fourth capacitors Cq(1), Cq(3),..., Cq(2N - 1) connected in series. One end of the third series circuit section 6 is connected to the other end 21d of the secondary winding 21b.

[0021] Then, the anode of diode Dp(n) (where n=1,2,3,...) is connected to one electrode of capacitor Cp(n), and the cathode of diode Dp(n) is connected to the other electrode of capacitor Cp(n+1). However, the cathode of the final stage diode Dp(2N) is connected to one electrode of capacitor Cp(2N-1). The anode of diode Dq(n) is connected to one electrode of capacitor Cq(n), and the cathode of diode Dq(n) is connected to the other electrode of capacitor Cq(n+1). However, the cathode of the final stage diode Dq(2N) is connected to one electrode of capacitor Cq(2N-1).

[0022] In this embodiment, the third capacitors Cp(1), Cp(3), ..., Cp(2N-1) of the second series circuit section 5 and the first capacitors Cp(2), Cp(4), ..., Cp(2N) of the first series circuit section 4 constitute the first half-wave rectified CW circuit section (first half-wave rectified boost circuit section) 7. Furthermore, the fourth capacitors Cq(1), Cq(3), ..., Cq(2N-1) of the third series circuit section 6 and the second capacitors Cq(2), Cq(4), ..., Cq(2N) of the first series circuit section 4 constitute the second half-wave rectified CW circuit section (second half-wave rectified boost circuit section) 8. The first series circuit section 4 is a common circuit section in the first half-wave rectifier type CW circuit section 7 and the second half-wave rectifier type CW circuit section 8.

[0023] The first half-wave rectifier CW circuit section 7 rectifies and boosts the AC voltage generated across the secondary winding 21b. The first half-wave rectifier CW circuit section 7 generates a DC output voltage from the AC voltage by repeatedly accumulating charge in the third capacitors Cp(1), Cp(3), ..., Cp(2N-1) and the first capacitors Cp(2), Cp(4), ..., Cp(2N), and rectifying it with the diode Dp(n). The second half-wave rectifier CW circuit section 8 rectifies and boosts the AC voltage generated across the secondary winding 21b in the opposite phase (180° phase difference) to that of the first half-wave rectifier CW circuit section 7. The second half-wave rectifier type CW circuit section 8 generates a DC output voltage from an AC voltage by repeatedly accumulating charge in the fourth capacitors Cq(1), Cq(3), ..., Cq(2N-1) and the second capacitors Cq(2), Cq(4), ..., Cq(2N), and rectifying it with the diode Dq(n).

[0024] The output voltages from the first half-wave rectifier CW circuit section 7 and the output voltage from the second half-wave rectifier CW circuit section 8 are added to the first DC voltage VDC1 in the first series circuit section 4 to generate the second DC voltage VDC2. The second DC voltage VDC2 is output from the other end of the first series circuit section 4 as the output voltage of the boost rectifier circuit 1 and supplied to the load RL. More specifically, in the boost rectifier circuit 1, the voltages generated at the electrodes of each of the first capacitors Cp(2), Cp(4), ..., Cp(2N) and the second capacitors Cq(2), Cq(4), ..., Cq(2N) in the first series circuit section 4 are added to the first DC voltage VDC1 in sequence to finally generate the second DC voltage VDC2. For example, if the absolute value of the first DC voltage VDC1 is 10kV, a voltage of 5kV is generated at the electrodes across each of the first capacitors Cp(2), Cp(4), ..., Cp(2N) and the second capacitors Cq(2), Cq(4), ..., Cq(2N), resulting in a final absolute value of approximately 40kV for the second DC voltage VDC2.

[0025] [Second Embodiment] Figure 2 is a circuit diagram showing the configuration of a boost rectifier circuit 1A according to a second embodiment of the present disclosure. The boost rectifier circuit 1A differs from the boost rectifier circuit 1 according to the first embodiment in that it is made up of N+1 (where N is an integer of 2 or more; the figure illustrates the case where N=3) third capacitors Cp(1), Cp(3), ..., Cp(2N+1) connected in series, and that 2N+1 diodes Dp(1), Dp(2), ..., Dp(2N+1) connect the first series circuit section 4 and the second series circuit section 5. In the example in Figure 2, the anode of diode Dp(1) is connected to the other electrode of capacitor Cq(2), and the cathode of diode Dp(1) is connected to one electrode of capacitor Cp(1). The anode of diode Dp(2n) (where n=1,2,3,...) is connected to one electrode of capacitor Cp(2n+1), and the cathode of diode Dp(2n) is connected to the other electrode of capacitor Cp(2n). The anode of diode Dp(2n+1) is connected to one electrode of capacitor Cp(2n), and the cathode of diode Dp(2n+1) is connected to one electrode of capacitor Cp(2n+1).

[0026] In the boost rectifier circuit 1A, the voltage of the first stage of the second series circuit section 5 is divided at the third capacitor Cp(1) and the third capacitor Cp(3) of the second series circuit section 5. As a result, the absolute value of the voltage generated at the third capacitor Cp(1) of the second series circuit section 5 in this embodiment is smaller than the absolute value of the voltage generated at the third capacitor Cp(1) of the second series circuit section 5 in the first embodiment.

[0027] [Third Embodiment] Figure 3 is a circuit diagram showing the configuration of a boost rectifier circuit 1B according to a third embodiment of the present disclosure. The boost rectifier circuit 1B differs from the boost rectifier circuit 1 according to the first embodiment in that it has a full-wave rectifier circuit section 3A instead of a full-wave rectifier circuit section 3. The full-wave rectifier circuit section 3A is connected to both ends of the secondary winding 21b. The full-wave rectifier circuit section 3A includes a capacitor 41 (first rectifier capacitor), a diode 42 (first diode), a diode 43 (second diode), a diode 44 (third diode), and a diode 45 (fourth diode). The anode of diode 42 is connected to one electrode of capacitor 41, and the cathode of diode 42 is connected to one end 21c of the secondary winding 21b. The anode of diode 43 is connected to one end 21c of the secondary winding 21b, and the cathode of diode 43 is connected to the other electrode of capacitor 41. The anode of diode 44 is connected to one electrode of capacitor 41, and the cathode of diode 44 is connected to the other end 21d of the secondary winding 21b. The anode of diode 45 is connected to the other end 21d of the secondary winding 21b, and the cathode of diode 45 is connected to the other electrode of capacitor 41. The other electrode of capacitor 41 is connected to the reference potential line GND.

[0028] The full-wave rectifier circuit 3A generates a first DC voltage VDC1 by rectifying the AC voltage generated in the secondary winding 21b. Unlike the full-wave rectifier circuit 3 of the first embodiment, the full-wave rectifier circuit 3A does not need to boost the AC voltage. In the full-wave rectifier circuit 3A, the positive and negative half-waves of the AC voltage in the secondary winding 21b are rectified by diodes 42 to 45, and the first DC voltage VDC1 is output from one electrode of capacitor 41. For example, if the DC power supply 11 generates a voltage of 50V and the winding ratio of the transformer 21 is 1:100, the amplitude value of the AC voltage in the secondary winding 21b may be 5kVp-p. In this case, the full-wave rectifier circuit 3A generates a first DC voltage VDC1 with an absolute value of 5kV. Then, in the boost rectifier circuit 1A, the voltages generated at the electrodes of the first capacitors Cp(2), Cp(4), ..., Cp(2N) and the second capacitors Cq(2), Cq(4), ..., Cq(2N) in the first series circuit section 4 are sequentially added to the first DC voltage VDC1, so that the absolute value of the second DC voltage VDC2 is ultimately about 35kV.

[0029] [Explanation of effects] The effects obtained by the boost rectifier circuits according to each embodiment having the above configuration will be described below. Figure 4 is a circuit diagram showing a boost rectifier circuit 10A according to the first comparative example. The boost rectifier circuit 10A comprises an AC power supply 16, a transformer 25, and a half-wave rectifier type CW circuit section 7A. In the boost rectifier circuit 10A, the secondary winding 25b and the resistor R1 are connected in series. The half-wave rectifier type CW circuit section 7A is connected between one end of the secondary winding 25b (the terminal not connected to the resistor R1) and one end of the resistor R1 (the terminal not connected to the secondary winding 25b). The half-wave rectifier type CW circuit section 7A has N2 capacitors Cd(1) to Cd(N2) (the figure illustrates the case where N2=6) and N2 diodes Dd(1) to Dd(N2). The odd-numbered stage capacitors Cd(2n-1) are connected in series with one end connected to one end of the secondary winding 25b. The even-numbered stage capacitors Cd(2n) are also connected in series with one end connected to one end of resistor R1. One end of resistor R1 is connected to the reference potential line GND. The anode of Dd(n) is connected to one electrode of capacitor Cd(n), and the cathode of Dd(n) is connected to the other electrode of capacitor Cd(n+1). However, the cathode of the final stage diode Dd(N2) is connected to one electrode of capacitor Cd(N2-1).

[0030] Figure 5 is a circuit diagram showing a boost rectifier circuit 10B relating to the second comparative example. The boost rectifier circuit 10B comprises a DC power supply 11, an H-bridge circuit 12, transformers 21 and 26, and a full-wave rectifier type CW circuit section 7B. The secondary winding 21b of transformer 21 and the secondary winding 26b of transformer 26 are connected in series with each other. In the boost rectifier circuit 10B, two resistors R3 and R4 are connected in series between the secondary windings 21b and 26b, and the connection point of resistors R3 and R4 is connected to the reference potential line GND.

[0031] The full-wave rectifier CW circuit section 7B has N3 capacitors Ce(1) to Ce(N3) (the figure illustrates the case where N3=3), N3 capacitors Cf(1) to Cf(N3), and N3 capacitors Cg(1) to Cg(N3). The capacitors Ce(n) are connected in series with one end connected to the connection point of resistors R3 and R4. The capacitors Cf(n) are connected in series with one end connected to the other end of a series circuit consisting of secondary windings 21b and 26b and resistors R3 and R4. The capacitors Cg(n) are also connected in series with one end connected to the other end of the same series circuit.

[0032] The full-wave rectifier CW circuit section 7B further includes 2N3 diodes De(1) to De(2N3) and 2N3 diodes Df(1) to Df(2N3). The cathodes of the odd-numbered diodes De(2n-1) are connected to one electrode of capacitor Cf(n), and the anodes of diodes De(2n-1) are connected to the other electrode of capacitor Ce(n). The cathodes of the even-numbered diodes De(2n) are connected to one electrode of capacitor Ce(n), and the anodes of diodes De(2n) are connected to the other electrode of capacitor Cf(n+1). However, the anode of the final stage diode De(2N3) is connected to one electrode of capacitor Cf(N3). The cathodes of the odd-numbered diodes Df(2n-1) are connected to one electrode of capacitor Cg(n), and the anodes of diodes Df(2n-1) are connected to the other electrode of capacitor Ce(n). The cathodes of the even-numbered diodes Df(2n) are connected to one electrode of capacitor Ce(n), and the anodes of diodes Df(2n) are connected to the other electrode of capacitor Cg(n+1). However, the anode of the final stage diode Df(2N3) is connected to one electrode of capacitor Cg(N3).

[0033] The following describes the effects of comparing the boost rectifier circuit 1A according to the second embodiment with the boost rectifier circuit 10A according to the first comparative example and the boost rectifier circuit 10B according to the second comparative example, using the boost rectifier circuit 1A as an example. Figure 6(a) is a diagram showing an example of the ripple voltage superimposed on the second DC voltage VDC2 generated by the boost rectifier circuit 1A, the boost rectifier circuit 10A, and the boost rectifier circuit 10B, respectively. Figure 6(b) shows an example of comparing the ripple voltage, number of components, number of transformers, and output voltage rise time for the boost rectifier circuit 1A, the boost rectifier circuit 10A, and the boost rectifier circuit 10B, respectively, with the values ​​for the boost rectifier circuit 1A converted to 1. In Figure 6(b), the ratios are shown when the ripple voltage, number of components, number of transformers, and output voltage rise time of the boost rectifier circuit 1A are set to 1. In the example shown in Figure 6, the DC power supply 11 generates a voltage of 50V, and the winding ratio of the transformer 21 is 1:100.

[0034] As shown in Figure 6(a), the ripple voltage in the boost rectifier circuit 1A according to the second embodiment is approximately 104Vp-p. In contrast, as shown in Figure 6(b), the ripple voltage in the boost rectifier circuit 10A according to the first comparative example is approximately 8 times that of the boost rectifier circuit 1A, and the ripple voltage in the boost rectifier circuit 10B according to the second comparative example is approximately 1 / 5 of that of the boost rectifier circuit 1A. However, since the boost rectifier circuit 10B includes two transformers 21 and 26, errors may occur between the inductances of the windings of transformers 21 and 26. In this case, the frequency of the ripple voltage may deviate from the frequency that drives the H-bridge circuit 12. In contrast, since the boost rectifier circuit 1A includes one transformer 21, it is not affected by inductance errors.

[0035] As shown in Figure 6(b), the number of components in the boost rectifier circuit 1A according to the second embodiment is reduced to approximately half that of the boost rectifier circuit 10B according to the second comparative example. Furthermore, since the boost rectifier circuit 10B includes two transformers, the number of transformers in the boost rectifier circuit 1A is reduced to half that of the boost rectifier circuit 10B. In addition, in the boost rectifier circuit 1A, the rise time required for the output voltage of the boost rectifier circuit 1A to rise from 0V to the second DC voltage VDC2 when the power is turned on is shorter than the rise time in the boost rectifier circuit 10A according to the first comparative example and the boost rectifier circuit 10B according to the second comparative example. In other words, the boost rectifier circuit 1A according to the second embodiment has the advantage of having fewer components than the boost rectifier circuit 10A according to the first comparative example and a smaller ripple voltage than the boost rectifier circuit 10B according to the second comparative example.

[0036] Next, the ripple voltage superimposed on the second DC voltage VDC2 is compared among the boost rectifier circuit 1A according to the second embodiment, the boost rectifier circuit 1 according to the first embodiment, and the boost rectifier circuit 1B according to the third embodiment. As mentioned above, when the ripple voltage in boost rectifier circuit 1A is approximately 104Vp-p, the ripple voltage in boost rectifier circuit 1 is also approximately 104Vp-p. That is, boost rectifier circuit 1A and boost rectifier circuit 1 exhibit almost the same ripple voltage characteristics. When the ripple voltage in boost rectifier circuit 1A is approximately 104Vp-p, the ripple voltage in boost rectifier circuit 1B is approximately 92.5Vp-p. The ripple voltage in boost rectifier circuit 1B is smaller than the ripple voltage in boost rectifier circuit 1A and boost rectifier circuit 1.

[0037] [Effects and Effects] In the boost rectifier circuits 1, 1A, and 1B, by placing the full-wave rectifier circuit section 3 or the full-wave rectifier circuit section 3A immediately after the transformer 21, it is possible to generate the first DC voltage VDC1 while suppressing ripple by utilizing both half-waves of the AC voltage generated by the secondary winding 21b of the transformer 21. Furthermore, the boost rectifier circuits 1, 1A, and 1B employ a half-wave rectifier type CW circuit, which has fewer components than a full-wave rectifier type CW circuit. In the boost rectifier circuits 1, 1A, and 1B, the phase of the output voltage from the first half-wave rectifier type CW circuit section 7 and the phase of the output voltage from the second half-wave rectifier type CW circuit section 8 are in opposite phases, so the noise superimposed on the first series circuit section 4 cancels each other out. In addition, the boost rectifier circuits 1, 1A, and 1B do not require the use of two transformers or a transformer with a center tap, as is the case with the full-wave rectifier type boost rectifier circuit. This allows for the generation of a second DC voltage VDC2 while effectively suppressing ripple. Therefore, by combining a full-wave rectifier circuit and a half-wave rectifier CW circuit, a simple structure can be achieved while suppressing ripple voltage.

[0038] The full-wave rectifier circuit section 3 may include capacitors 31, 32, 33, diodes 34, 35, 36, and 37. The anode of diode 34 may be connected to one electrode of capacitor 31, and the cathode of diode 34 may be connected to one electrode of capacitor 32. The anode of diode 35 may be connected to one electrode of capacitor 32, and the cathode of diode 35 may be connected to one end 21c of the secondary winding 21b. The anode of diode 36 may be connected to one electrode of capacitor 31, and the cathode of diode 36 may be connected to one electrode of capacitor 33. The anode of diode 37 may be connected to one electrode of capacitor 33, and the cathode of diode 37 may be connected to the other end 21d of the secondary winding 21b. The other electrode of capacitor 31 may be connected to the reference potential line GND. The other electrode of capacitor 32 may be connected to the other end 21d of the secondary winding 21b. The other electrode of capacitor 33 may be connected to one end 21c of the secondary winding 21b. In this case, the amount of charge stored in capacitor 31 can be increased by utilizing the positive and negative half-waves of the AC voltage generated in the secondary winding 21b, thereby increasing the voltage boost ratio in the full-wave rectifier circuit 3.

[0039] In the full-wave rectifier circuit section 3A, the anode of diode 42 may be connected to one electrode of capacitor 41, and the cathode of diode 42 may be connected to one end 21c of the secondary winding 21b. The anode of diode 43 may be connected to one end 21c of the secondary winding 21b, and the cathode of diode 43 may be connected to the other electrode of capacitor 41. The anode of diode 44 may be connected to one electrode of capacitor 41, and the cathode of diode 44 may be connected to the other end 21d of the secondary winding 21b. The anode of diode 45 may be connected to the other end 21d of the secondary winding 21b, and the cathode of diode 45 may be connected to the other electrode of capacitor 41. The other electrode of capacitor 41 may be connected to the reference potential line GND. In this case, the full-wave rectifier circuit section also has a simple configuration with fewer components, making it easier to further reduce the number of components in the boost rectifier circuit. [Differentiation]

[0040] The boost rectifier circuits 1, 1A, and 1B in this disclosure are not limited to the embodiments described above, and various other modifications are possible. For example, in each of the above embodiments, this disclosure may be applied to a boost rectifier circuit for outputting a negative high voltage, or it may be applied to a boost rectifier circuit for outputting a positive high voltage. In that case, the orientation of the diodes in each embodiment will be reversed. Furthermore, although the boost rectifier circuits 1, 1A, and 1B in each of the above embodiments include a CW circuit, they can be configured with various other boost rectifier circuits, not limited to a CW circuit.

[0041] Figure 7 is a circuit diagram showing the configuration of a boost rectifier circuit according to the first modified example. The boost rectifier circuit 1C according to the first modified example differs from the boost rectifier circuit 1 according to the first embodiment in that it has a capacitor 61, diode 62, diode 63, capacitor 64, diode 65, diode 66, and a full-wave rectifier circuit 3B instead of diodes 22, diode 23, and full-wave rectifier circuit 3. The other electrode of capacitor 61 is connected to the other end 21d of the secondary winding 21b. One electrode of capacitor 61 is connected to the cathode of diode 62 and the anode of diode 63. The anode of diode 62 is connected to the other electrode of the second capacitor Cq(2), which is the input terminal of the first series circuit 4. The cathode of diode 63 is connected to one end 21c of the secondary winding 21b. The other electrode of capacitor 64 is connected to one end 21c of the secondary winding 21b. One electrode of capacitor 64 is connected to the cathode of diode 65 and the anode of diode 66. The anode of diode 65 is connected to the other electrode of the second capacitor Cq(2). The cathode of diode 66 is connected to the other end 21d of the secondary winding 21b.

[0042] The full-wave rectifier circuit section 3B is connected to both ends of the secondary winding 21b. The full-wave rectifier circuit section 3B includes capacitor 51, capacitor 52, diode 53, diode 54, diode 55, and diode 56. The cathode of diode 53 is connected to the other electrode of capacitor 51, and the anode of diode 53 is connected to one end 21c of the secondary winding 21b. The cathode of diode 54 is connected to one end 21c of the secondary winding 21b, and the anode of diode 54 is connected to one electrode of capacitor 51. The other electrode of capacitor 52 is connected to one electrode of capacitor 51, and one electrode of capacitor 52 is connected to the other electrode of the second capacitor Cq(2). The other electrode of capacitor 51 is connected to the reference potential line GND. The cathode of diode 55 is connected to the other electrode of capacitor 51, and the anode of diode 55 is connected to the other end 21d of the secondary winding 21b. The cathode of diode 56 is connected to the other end 21d of the secondary winding 21b, and the anode of diode 56 is connected to one electrode of capacitor 51.

[0043] The full-wave rectifier circuit 3B generates a first DC voltage VDC1 by rectifying the AC voltage generated in the secondary winding 21b. Unlike the full-wave rectifier circuit 3 of the first embodiment, the full-wave rectifier circuit 3B does not need to boost the AC voltage. In the full-wave rectifier circuit 3B, the positive and negative half-waves of the AC voltage in the secondary winding 21b are rectified by diodes 53 to 56, and the first DC voltage VDC1 is output from one electrode of capacitor 52. That is, because capacitors 51 and 52 are connected in series, the magnitude of the voltage generated in each capacitor is reduced. For example, if the absolute value of the first DC voltage VDC1 is 10kV, the sum of the voltages generated in capacitor 51 and capacitor 52 will be 10kV. In this case, the ratio of the voltages generated in capacitor 51 and capacitor 52 may change depending on the magnitude of the load RL. For example, the ratio of the voltage generated at capacitor 51 to the voltage generated at capacitor 52 may be 6:4 or 5:5.

[0044] Figure 8 is a circuit diagram showing the configuration of a boost rectifier circuit according to the second modified example. The boost rectifier circuit 1D differs from the boost rectifier circuit 1C of the first modified example in that it is made up of N+1 (where N is an integer of 2 or more; the figure illustrates the case where N=3) third capacitors Cp(1), Cp(3), ..., Cp(2N+1) connected in series, and that 2N+1 diodes Dp(1), Dp(2), ..., Dp(2N+1) connect the first series circuit section 4 and the second series circuit section 5. In the example in Figure 8, the anode of diode Dp(1) is connected to the other electrode of capacitor Cq(2), and the cathode of diode Dp(1) is connected to one electrode of capacitor Cp(1). The anode of diode Dp(2n) (where n=1,2,3,...) is connected to one electrode of capacitor Cp(2n+1), and the cathode of diode Dp(2n) is connected to the other electrode of capacitor Cp(2n). The anode of diode Dp(2n+1) is connected to one electrode of capacitor Cp(2n), and the cathode of diode Dp(2n+1) is connected to one electrode of capacitor Cp(2n+1).

[0045] In the boost rectifier circuit 1D, the voltage of the first stage of the second series circuit section 5 is divided at the third capacitor Cp(1) and the third capacitor Cp(3) of the second series circuit section 5. As a result, the absolute value of the voltage generated at the third capacitor Cp(1) of the second series circuit section 5 in this modified example is smaller than the absolute value of the voltage generated at the third capacitor Cp(1) of the second series circuit section 5 in the first modified example. [Explanation of Symbols]

[0046] 1, 1A, 1B... Boost rectifier circuit, 3, 3A... Full-wave rectifier circuit section, 4... First series circuit section, 5... Second series circuit section, 6... Third series circuit section, 7... First half-wave rectifier CW circuit section (first half-wave rectifier boost circuit section), 8... Second half-wave rectifier CW circuit section (second half-wave rectifier boost circuit section), 21... Transformer, 21a... Primary winding, 21b... Secondary winding, 21c... One end of the transformer, 21d... Other end of the transformer, 31, 41... Capacitor (first rectifier capacitor), 32... Capacitor (second rectifier capacitor), 33... Capacitor (third rectifier capacitor) 34, 42... Diode (first diode), 35, 43... Diode (second diode), 36, 44... Diode (third diode), 37, 45... Diode (fourth diode), Cp(2), Cp(4), Cp(2N)... First capacitor, Cq(2), Cq(4), Cq(2N)... Second capacitor, Cp(1), Cp(3), Cp(2N-1)... Third capacitor, Cq(1), Cq(3), Cq(2N-1)... Fourth capacitor, GND... Reference potential line, VDC1... First DC voltage, VDC2... Second DC voltage.

Claims

1. A transformer including a primary winding and a secondary winding, wherein an AC voltage is input to the primary winding, A full-wave rectifier circuit section connected to the secondary winding generates a first DC voltage by rectifying the AC voltage generated in the secondary winding, A first series circuit section is formed by alternately connecting multiple first capacitors and multiple second capacitors in series, A second series circuit section consisting of multiple third capacitors connected in series, A third series circuit section consisting of multiple fourth capacitors connected in series, Equipped with, One end of the second series circuit section is connected to one end of the secondary winding, One end of the third series circuit section is connected to the other end of the secondary winding, One end of the first series circuit is connected to the output terminal of the full-wave rectifier circuit, The third capacitor of the second series circuit section and the first capacitor of the first series circuit section constitute the first half-wave rectifier boost circuit section. The fourth capacitor of the third series circuit section and the second capacitor of the first series circuit section constitute a second half-wave rectifier boost circuit section. The first half-wave rectifier boost circuit section rectifies and boosts the AC voltage generated in the secondary winding, The second half-wave rectifier boost circuit rectifies and boosts the AC voltage generated in the secondary winding in the opposite phase to that of the first half-wave rectifier boost circuit. A boost rectifier circuit in which the output voltage from the first half-wave rectifier boost circuit and the output voltage from the second half-wave rectifier boost circuit are added to the first DC voltage in the first series circuit to generate a second DC voltage.

2. The aforementioned full-wave rectifier circuit section is, It includes a first rectifier capacitor, a second rectifier capacitor, a third rectifier capacitor, a first diode, a second diode, a third diode, and a fourth diode. The anode of the first diode is connected to one electrode of the first rectifier capacitor, and the cathode of the first diode is connected to one electrode of the second rectifier capacitor. The anode of the second diode is connected to one electrode of the second rectifier capacitor, and the cathode of the second diode is connected to one end of the secondary winding. The anode of the third diode is connected to one electrode of the first rectifier capacitor, and the cathode of the third diode is connected to one electrode of the third rectifier capacitor. The anode of the fourth diode is connected to one electrode of the third rectifier capacitor, and the cathode of the fourth diode is connected to the other end of the secondary winding. The other electrode of the first rectifier capacitor is connected to a reference potential line. The other electrode of the second rectifier capacitor is connected to the other end of the secondary winding. The boost rectifier circuit according to claim 1, wherein the other electrode of the third rectifier capacitor is connected to one end of the secondary winding.

3. The aforementioned full-wave rectifier circuit section is, It includes a first rectifier capacitor, a first diode, a second diode, a third diode, and a fourth diode. The anode of the first diode is connected to one electrode of the first rectifier capacitor, and the cathode of the first diode is connected to one end of the secondary winding. The anode of the second diode is connected to one end of the secondary winding, and the cathode of the second diode is connected to the other electrode of the first rectifier capacitor. The anode of the third diode is connected to one electrode of the first rectifier capacitor, and the cathode of the third diode is connected to the other end of the secondary winding. The anode of the fourth diode is connected to the other end of the secondary winding, and the cathode of the fourth diode is connected to the other electrode of the first rectifier capacitor. The boost rectifier circuit according to claim 1 or 2, wherein the other electrode of the first rectifier capacitor is connected to a reference potential line.

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