JPH07231648A - Power supply unit - Google Patents

Abstract

PURPOSE:To provide a small filter circuit and a simple control circuit in a power supply unit that includes a switching element and a voltage multiplier circuit made of a capacitor and a diode as a switching means, by limiting a change in the number of pulses in a narrow range so that noises are limited in a given range when the pulses are fed to a switching element. CONSTITUTION:A power supply unit includes a first-group output means for generating a maximum voltage of E, 3E, 5E, 7E or 9E, each obtained from a minimum power-supply voltage multiplied by odd numbers, and a second group output means for generating a voltage 2E, 4E, 6E, and 8E, each obtained from an minimum power-supply voltage multiplied by even numbers. Then, the first-group and second-group output means are alloted in different voltage ranges. In addition, the power supply unit includes switching means S21 to S28 for switching the connection between each output means and a load, and control means 1 and 11 for controlling switching elements in a way that the output voltage from the output means changes in the allotted range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for supplying a high frequency current to a load by a high frequency switching operation.

[0002]

2. Description of the Related Art A circuit diagram of a conventional example is shown in FIG. This circuit
To explain the basic configuration of, switch in parallel with DC power supply E
Element S₁, S₂Connect the series circuit of and switch
Element S ₂Is connected in parallel with the multiplication circuit X, and the multiplication circuit X
A load 2 is connected to the output. The multiplication circuit X is
Touching element S₁And S₂Alternating ON / OFF operation of DC
This is a circuit that can generate a higher voltage than the power source E,
Uses the Crokcroft-Walton circuit.

The operation of the multiplication circuit X will be described below. The switching elements S ₁ and S ₂ are alternately turned on and off.
When the switching element S ₁ is turned on by the control signal from the control circuit 1, the capacitor C ₁ is charged to the voltage E via the diode D ₁ . Next, when the switching element S ₁ is turned off and the switching element S ₂ is turned on, the capacitors C ₁ and C ₂ are connected via the diode D _2, and a part of the charge of the capacitor C ₁ moves to the capacitor C _2. , The capacitor C ₂ is charged. Again, switching element S ₂
When the switching element S ₁ is turned off and the switching element S ₁ is turned on, the capacitor C ₁ is charged to the voltage E through the diode D _1, and a part of the electric charge of the capacitor C ₂ moves to the capacitor C ₃ through the diode D ₃ , The capacitor C ₃ is charged. By repeating this, the capacitors C _{1 to} C ₅ are charged, and the maximum voltage is charged to the voltage E for each capacitor. In this way, it is possible to apply a maximum voltage of 3E to the load 2. Further, even if one end (point A) of the load 2 is connected to the positive electrode side of the power source E, a maximum voltage of 3E can be applied, and if connected to the negative electrode side of the power source E, a maximum of 4E can be applied.
Can be applied.

Further, the charge transfer between the capacitors is not performed unless the switching element operates. In this case,
The electric charge of each capacitor is discharged to the load 2 via each diode. This causes the voltage of the load 2 to decrease. Therefore, by repeating the operation of the switching element, that is, by controlling the operating frequency, the voltage V of the load 2 is reduced.
It becomes possible to control ₃ .

FIG. 8 shows an operation waveform diagram of a conventional example. This figure
8 is a switching element S using the circuit of FIG.₁, S
₂Operation of supplying a substantially half-wave waveform to the load 2
Is shown. Time t₀And the switching element S₁Control
When turned on by the control signal from the control circuit 1, the capacitor C₁
Is the diode D₁Is charged to voltage E via. Times of Day
t₁And the switching element S₁Turn off and switch
Element S₂When is turned on, the capacitor C₁And C₂Is a dio
Mode D₂Connected via a capacitor C₁Of the charge
Part is capacitor C₂Go to and condenser C₂Is charged
To be done. Time t ₂And the switching element S₂Turned off,
The voltage of each capacitor is almost held. Time t₃So
Itching element S₁When is turned on, the capacitor C₁Is da
Iodo D₁Is charged up to voltage E via
C₂Part of the electric charge of the diode D ₃Through the capacitor
C₃Go to and condenser C₃Is charged. Time t_Four
And the switching element S₁Turns off, switching element
S₂When is turned on, the capacitor C₃And C_FourIs a diode
D_FourConnected via a capacitor C₃Part of the charge
Is the capacitor C_FourGo to and condenser C_FourIs charged
It Time t_FiveAnd the switching element S₂Turns off each
The voltage of the capacitor is almost maintained. Time t₆And switch
Holding element S₁When is turned on, the capacitor C₁Is a dio
Mode D₁Is charged to a voltage E via a capacitor C_Four
Part of the electric charge of the diode D_FiveThrough the capacitor C_Five
Go to and condenser C_FiveIs charged. This repeat
And capacitor C₁~ C_FiveWill go charged.

Due to the operation of the switching elements S ₁ and S ₂ , the load voltage V ₃ rises from time t _{7 to} t ₁₁ , reaches the maximum value of the voltage at time t ₁₂ , and then the operating frequency of the switching element is changed. To lower the voltage V ₃ . At time t ₁₃ , the voltage V ₃ becomes minimum, and then rises. In this case, the operating frequency of the switching element (the number of signal pulses to the switching element per time) is shown in FIG.
As shown in (a) and (b), the supply voltage V ₃ to the load 2 can be made substantially sinusoidal by changing it to be sinusoidal.

[0007] Thus, the two series circuit of the switching elements S _1, S ₂ connected in parallel with the DC power source E, in parallel with the switching element S _2, alternately on and off of the switching elements S ₁ and S ₂ connect the multiplier X which can generate a high voltage from the power source in operation, load on the output of the multiplier circuit X 2, the operating frequency of the switching element S _1, S ₂ (per time to the switching element S _1, S ₂ The signal voltage V ₃ to the load 2 can be made substantially sinusoidal by varying the number of signal pulses of the capacitors C ₁ to C by increasing the operating frequency.
Since the ₅ and switching element S _1, S ₂ can be reduced, but can provide a compact power supply that can generate any ripple voltage.

However, in this conventional example, when a voltage varying from zero to the maximum is applied to the load, it is necessary to change the number of pulses supplied to the switching element in a wide range, and noise in a wide range of frequencies is generated. There are problems that the filter circuit becomes large and the control circuit becomes complicated.

[0009]

As described above, in the conventional power supply device, when the voltage varying from zero to the maximum is applied to the load, it is necessary to change the number of pulses supplied to the switching element in a wide range. There is a problem that noise in a wide range of frequencies occurs, the filter circuit becomes large, and the control circuit becomes complicated.

The present invention has been made in view of the above points, and an object of the present invention is to load a load by using a voltage multiplication circuit composed of a capacitor and a switching element such as a diode and a switching element. In a power supply device capable of supplying a wide range of output voltage, by limiting the change in the number of pulses supplied to the switching element within a relatively narrow range, the noise generation frequency range is limited, and the filter circuit is downsized and the control circuit is reduced. Is to realize simplification of.

[0011]

According to the present invention, in order to solve the above-mentioned problems, as shown in FIG. 1, first and second switching elements S ₁ ,
A series circuit of S ₂ (or S ₁₁ , S ₁₂ ) is connected, and at least a capacitor and a switching element are provided between both ends of one switching element, and a voltage is generated by the on / off operation of the first and second switching elements. Connect a voltage variable means such as Cockcroft Walton circuit to generate
A power supply device in which one end of a load 2 is connected to at least the output of the voltage varying means, wherein the voltage varying means has a maximum voltage that is an odd multiple E, 3E, 5E, 7E, 9 of a set minimum power source voltage E.
The output stage of the first group, which is E, and even multiples 2E, 4E, 6E,
8E has a second group of output stages, each output stage has a region for sharing output voltages different from each other, and means S _{21 to} S ₂₈ for switching the connection between the load 2 and each output stage, and a voltage varying means. Control means 1 and 11 for controlling the on / off operation of the switching element so that the output voltage from the output stage changes only within the sharing region of the output stage.

[0012]

As described above, according to the present invention, when a voltage varying from zero to the maximum is applied to the load, the voltage range in charge of each capacitor is set, and switching is performed so that the voltage varies within the voltage range. Since the operating frequency of the element is controlled, it is not necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise generation is limited, the filter circuit can be downsized, and the control circuit can be simplified.

[0013]

1 is a circuit diagram of a first embodiment of the present invention.
The basic configuration of the main circuit of this embodiment is formed by connecting two series circuits of the switching elements S _1, S ₂ in parallel with the power supply 2E, in parallel with the switching element S _2, the switching element S ₁ and S ₂ alternating capacitor C ₁ -C ₇ can generate a high voltage from the power on-off operation, it connects the multiplier circuit composed of diodes D ₁ to D _7. Capacitor C _1, C ₃ constituting each of the output stage of the multiplier circuit, C _5, C ₇
Is connected to one end A of the load 2 via switching elements S _{21 to} S ₂₄ . The other end B of the load 2 has a diode D ₂₁
And a power source E to connect the switching elements S ₁ and S _{2 to} the connection point. On the other hand, another set, a series circuit of two switching elements S _11, S ₁₂ are connected in parallel with the power supply 2E, in parallel with the switching element S _12, in alternating on and off operation of the switching element S ₁₁ and S ₁₂ capacitor C ₁₁ -C ₁₇ can generate a high voltage from the power supply connects the multiplier circuit consists of a diode D ₁₁ to D _17. Capacitor C _11, C ₁₃ constituting each of the output stage of the multiplier circuit, C _15, C ₁₇
Is connected to one end A of the load via the switching elements S _{25 to} S _28.
Connected to. The other end B of the load is connected to the connection point between the switching elements S ₁₁ and S ₁₂ via the diode D ₂₂ .

FIG. 2 shows an operation waveform diagram of this embodiment. FIG. 2 shows an operation of supplying a substantially half-wave waveform to the load 2 by controlling the switching element using the circuit of FIG. The power source E is connected to the multiplication circuit on the side of the switching element S ₁ when the switching element S ₁₈ is turned on, and the switching elements S ₁₉ and S ₂₀ are turned off. To the load 2, the voltages 9E, 7E, 5E, 3E, which are odd multiples of the power source E, can be supplied from the terminals of the capacitors C ₇ , C ₅ , C ₃ , C ₁ by the operation of the switching elements S ₁ , S _2. it can. Also, the multiplier circuit side of the switching element S _11, the switching element S _11, by the operation of the S _12, an even multiple of the voltage 8E power E, 6E, 4E, each of the 2E capacitors _{C 17, C 15, C 13} , The load 2 can be supplied from the terminal of C ₁₁ .

Here, as shown in FIG.
Supply voltage V₃The operation of creating a
It First, the voltage V₃At time t₁From 4E at time t₂Of 5
If it changes to E, the capacitor C₃The output of
Holding element S_{twenty two}Is connected to load 2 by turning on
It Switching element S from point B₁And S₂Between the connection points of
Voltage is E and switching element S₁, S₂On
・ Capacitor C due to low off-operation frequency₁
The voltage across both ends is (4E-E) /2=3E/2=1.5E
Yes, capacitor C₃The voltage across both ends is 1.5E
It Where time t ₂To the switching element S₁
And S₂When the operating frequency of is increased, the capacitor C₁
And C₃Both ends of the voltage rise to 2E, and the voltage V₃
Can be increased from 4E to 5E. Time t
₂At the switching element S_{twenty two}Switch off
Element S₂₇Is turned on, the capacitor C₁₅Output is load
Connected to 2. Switching element S₁₁, S₁₂On
Due to the low off-frequency, capacitor C₁₁of
Both ends voltage is 5E / 3 = 1.67E, capacitor C₁₃，
C₁₅The voltage across both ends is 1.67E. Where time
Tick t₃Switching element S over₁₁And S₁₂Operating frequency
As the number increases, the capacitor C₁₁And C₁₃And C ₁₅Both
The terminal voltage rises to 2E, and the voltage V₃From 5E
You can increase to 6E. Time t₃become
And the switching element S₂₇Turns off, switching element
S_{twenty three}Turns on. After that, the same operation is repeated until the voltage wave
Relay the shape.

Thus, for example, when changing the supply voltage to the load from 4E to 5E, the voltage of the capacitor changes from 1.5E to 2E, and from 5E to 6E.
In this case, since the voltage of the capacitor changes from 1.67E to 2E, unlike the case of changing from zero to 2E as in the conventional case, the switching elements S ₁ , S _{2 and} S ₁₁ , S are different. It is possible to keep the changes in the ₁₂ operating frequencies within a small range. When the voltage to the load is changed from zero to E, the switching element S ₁₈ is turned off and the switching elements S ₁₉ and S ₂₀ are alternately turned on / off.

As described above, when a voltage varying from zero to the maximum is applied to the load, a voltage range in charge of each capacitor is provided, and the operating frequency of the switching element is controlled so that the voltage varies within the voltage range. It is not necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise generation is reduced, the filter circuit can be downsized, and the control circuit can be simplified.

A circuit diagram of the second embodiment of the present invention is shown in FIG. The basic configuration of the main circuit of this embodiment is almost the same as that of the first embodiment, and the power supply 2E is shared. In this case as well, for example, when changing the voltage supplied to the load 2 from 4E to 5E, the voltage of the capacitor changes from 1.5E to 2E, and when changing from 5E to 6E, the capacitor changes. Since the voltage changes from 1.67E to 2E, it is possible to keep the change in the operating frequency of the switching element within a small range, unlike the case where the voltage is changed from zero to 2E as in the conventional case. In this way, when applying a voltage that changes from zero to the maximum to the load, a voltage range in charge of each capacitor is provided and the operating frequency of the switching element is controlled so that the voltage changes within that voltage range. It is possible to reduce the frequency range of noise generation, reduce the size of the filter circuit, and simplify the control circuit without having to change the number of pulses to the wide range.

A circuit diagram of the third embodiment of the present invention is shown in FIG. In the main circuit of this embodiment, the multiplication circuit is shared, and for the operation on the side of the switching element S ₁ in the first embodiment, the switching element S ₁₈ is turned on, the switching element S ₃₁ is turned off, and the switching element S ₃₁ is turned off. Due to the operation on the S ₁₁ side, the switching element S ₃₁ is turned on and the switching element S ₁₈ is turned off. The other operation is almost the same as that of the first embodiment. In this case as well,
It is not necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise generation is reduced, the filter circuit can be downsized, and the control circuit can be simplified.

A circuit diagram of the fourth embodiment of the present invention is shown in FIG. In the present embodiment, the power conversion circuit H having a multiplication circuit is not directly connected to the load 2, but from points A and B in FIG. 1 via a polarity reversal circuit composed of switching elements S _{41 to} S _44. , The load 2 is connected, and electric power can be supplied while the supply voltage to the load 2 is substantially sinusoidal. That is, each time the half-wave waveform shown in FIG. 2 becomes zero, the switching elements S ₄₁ and S ₄₄ are turned on and the switching element S is turned on.
₄₂ and S ₄₃ are off, and switching elements S ₄₁ and S ₄₄
Is off and the switching elements S ₄₂ and S ₄₃ are on. Also in this case, similarly, it is not necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise generation is reduced, the filter circuit can be downsized, and the control circuit can be simplified.

A circuit diagram of the fifth embodiment of the present invention is shown in FIG. In this embodiment, two sets of the power conversion circuits surrounded by broken lines in FIG. 1 are prepared, and the load 2 is connected between the output terminals of _one power conversion circuit H ₁ and the other power conversion circuit H _2. .
When one power conversion circuit H ₁ operates to output a half-sine wave voltage, the other power conversion circuit H ₂ does not operate (see FIG.
Switching elements S ₁ and S ₂ and switching elements S ₁₁ and S ₁₂ do not operate, or switching element S ₂₀
~ S ₂₈ is off), and the switching element S ₅₂ is on. When the power conversion circuit H ₂ operates and outputs a half-sine wave voltage, the power conversion circuit H ₁ does not operate and the switching element S ₅₁ is on. This makes it possible to supply alternating-current sinusoidal power to the load 2. Also in this case, similarly, it is not necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise generation is reduced, the filter circuit can be downsized, and the control circuit can be simplified.

[0022]

According to the present invention, when a voltage varying from zero to the maximum is applied to the load, a voltage range in charge of each capacitor is provided, and the operating frequency of the switching element is adjusted so that the voltage varies within the voltage range. Since it is necessary to change the number of pulses to the switching element in a wide range, the frequency range of noise is reduced, the filter circuit can be downsized, and the control circuit can be simplified.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

FIG. 2 is an operation waveform diagram of the first embodiment of the present invention.

FIG. 3 is a circuit diagram of a second embodiment of the present invention.

FIG. 4 is a circuit diagram of a third embodiment of the present invention.

FIG. 5 is a circuit diagram of a fourth embodiment of the present invention.

FIG. 6 is a circuit diagram of a fifth embodiment of the present invention.

FIG. 7 is a circuit of a conventional example.

FIG. 8 is an operation waveform diagram of a conventional example.

[Explanation of symbols]

1 Control circuit 2 Load E DC power supply S _{1 to} S ₅₂ Switching element C _{1 to} C ₂₀ Capacitor D _{1 to} D ₂₂ Diode

Claims (5)

[Claims] 1. A series circuit of first and second switching elements is connected in parallel with a DC power source, and at least a capacitor and a switching element are provided between both ends of one switching element. A power supply device in which voltage varying means for generating a voltage by turning on / off a switching element is connected, and one end of a load is connected to at least the output of the voltage varying means, wherein the voltage varying means has a maximum voltage set to a minimum power source. It has an output stage of the first group that is an odd multiple of the voltage and an output stage of the second group that is an even multiple, and each output stage has a different sharing region of the output voltage, and the connection between the load and each output stage is A switching means and a means for controlling the on / off operation of the switching element so that the output voltage from each output stage of the voltage varying means changes only within the sharing region of the output stage. And power supply. 2. A first group of output stages having means for switching whether or not to connect a load to a set minimum power supply voltage, wherein the maximum voltage is an odd multiple of the set minimum power supply voltage, and a second group of even multiples. 2. The power supply device according to claim 1, wherein the output stage is shared. 3. The power supply device according to claim 1, further comprising means for inverting the polarity of the output voltage between the voltage varying means and the load. 4. The power supply device according to claim 1, further comprising control means for changing the output voltage of the voltage varying means according to the state of a load. 5. The power supply device according to claim 1, further comprising a plurality of the voltage varying means, which is configured to supply a differential voltage of each voltage varying means to a load.