JPH06245376A - Power source - Google Patents

Abstract

PURPOSE:To provide a power source to be coped with by detecting and controlling characteristic change of a DC generator having inherent characteristics of a fuel cell, etc. CONSTITUTION:The power source comprises a main circuit and controller 3, an output error voltage amplifier B for comparing an output detection voltage Vos proportional to an output current of the controller 3 with a reference output voltage Vor to amplify and supply its differential voltage to the controller 3, an input error voltage amplifier C for comparing an input detection voltage Vis of the controller 3 with a reference input voltage Vir, and a reference output voltage controller D for varying the voltage Vor when the voltage Vis is lower than the voltage Vir.

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 capable of supplying stable power to a load by using a direct current power generation device such as a fuel cell having a relatively high output impedance as a power supply source.

[0002]

2. Description of the Related Art Conventionally, a power supply device which is connected to a DC power generation device such as a storage battery, a fuel cell or a solar cell and supplies stable power to a load detects only an output voltage or an output current and outputs the output voltage or the output. The current is proportionally converted into the output detection voltage, and the detection voltage is compared with the reference output voltage to amplify the output error voltage, which is used as a control signal to control the power supplied to the load.

FIG. 10 shows the configuration of a conventional power supply device.
In the figure, A is a conventional power supply device, 1 is a direct current generator such as a fuel cell, 2 is a load, 3 is a main circuit / control circuit, 4 is an output current detection converter, 5 is an output error voltage amplifier, and 6 is It is a reference voltage source.

In FIG. 10, the output of the DC generator 1 is connected to the input of the power supply A, and the output of the power supply A is connected to the load 2. The main circuit / control circuit 3 is composed of a dropper circuit, a switching power supply circuit, or the like. The direct current power generated by the direct current power generator 1 is controlled by the power source device A with respect to the output current Io, and is supplied to the load 2 as stable direct current power.

The output current Io of the main circuit / control circuit 3 of the power supply device A is detected by the output current detection converter 4, and is input to the inverting input of the output error voltage amplifier 5 as the output detection voltage Vos proportional to the output current Io. To be done. On the other hand, the reference output voltage Vor of the reference output voltage source 6 is input to the non-inverting input of the output error amplifier 5. Both voltages Vos and Vor input to the output error amplifier 5 are differentially amplified and become a differential amplification control signal S, which is input to the control input of the main circuit / control circuit 3 to feedback control the output current Io.

When the output current Io increases, the output detection voltage V
os rises, the differential amplification control signal S of the output error voltage amplifier 5 decreases, and it is input as a control input of the main circuit / control circuit 3. Therefore, when the main circuit / control circuit 3 is formed of a dropper circuit, the output current Io is suppressed, and when the main circuit / control circuit 3 is formed of a switching circuit, the duty ratio of the switching pulse is reduced to reduce the output current Io.

On the contrary, when the output current Io decreases, the output detection voltage Vos decreases and the differential amplification control signal S of the output error voltage amplifier 6 increases, so that the output current Io works to increase. Since the conventional power supply device A is configured in this way, it is possible to supply stable power to the load 2 according to the fluctuation of the output current Io.

[0008]

However, the conventional power supply device A does not consider the characteristics of the DC power generation device 1 used as a power supply source. Therefore, when using a storage battery, a fuel cell, or the like, which has a relatively high output impedance and has a large characteristic deterioration such as a decrease in output capacity due to overload or aging, the conventional power supply device A is Since the decrease in the output capacity of the DC power generator 1 due to these causes cannot be detected, the DC power generator 1 is overloaded with the electric power of the output capacity or more, which further increases the characteristic deterioration of the DC power generator 1. There are drawbacks such that the power supply from the DC power generator 1 is stopped and the DC power generator 1 is damaged.

Further, when the power supply device A is stopped due to overload, the output disappears, the output voltage of the DC generator 1 becomes high, and the power supply device A is ready to start operation again. Since the output cannot be supplied, there is a problem that the operation and stop are repeated intermittently.

Further, when a converter is connected as the load 2, the converter is generally solid-stated with a semiconductor. Therefore, when the output power Po of the power supply device A decreases, the input power of the converter sharply decreases. However, there is a problem that the control operation cannot be performed and the operation is stopped in an instant. Here, the present invention is to provide a power supply device capable of detecting and controlling the characteristic change of a DC power generating device having a characteristic such as a fuel cell and corresponding thereto.

[0011]

The above object can be achieved by the present invention by adopting the novel characteristic construction means listed below. That is, the first feature of the present invention is to provide a main circuit / control circuit and a main circuit / control circuit in a power supply device that is connected to the output of a DC power generator such as a fuel cell and supplies stable power to a load. An output error voltage amplification circuit that compares an output detection voltage proportional to an output current with a reference output voltage, amplifies the difference voltage and supplies the difference voltage to the main circuit / control circuit, and an input detection voltage and reference of the main circuit / control circuit A power supply device comprising an input error voltage amplifier circuit for comparing input voltages, and a reference output voltage control circuit for changing the reference output voltage when an input detection voltage is lower than the reference input voltage.

A second feature of the present invention is, in a power supply device for supplying stable power to a load by connecting to an output of a direct current power generation device such as a fuel cell, a main circuit / control circuit and the main circuit / control circuit. An output error voltage amplification circuit that compares an output detection voltage proportional to the output current of the reference output voltage with a reference output voltage and amplifies the difference voltage to supply to the main circuit / control circuit; and an input detection current of the main circuit / control circuit. A power supply device comprising: an output voltage control circuit that compares the corresponding reference input voltages and changes the reference output voltage when the input current is larger than a set current value.

A third feature of the present invention is, in a power supply device for supplying stable power to a load by connecting to an output of a direct current power generation device such as a fuel cell, a main circuit / control circuit and the main circuit / control circuit. An output error voltage amplification circuit that compares the output detection voltage proportional to the output current of the reference output voltage with the reference output voltage, amplifies the difference voltage and supplies the difference voltage to the main circuit / control circuit, and the input detection voltage of the main circuit / control circuit. A first input error voltage amplifier circuit for comparing the reference input voltage, a second input error voltage amplifier circuit for comparing the input current of the main circuit / control circuit and the reference input voltage proportional thereto, and the input voltage is set. A power supply device comprising: a reference voltage control circuit that changes the reference output voltage when the voltage is lower than a voltage value or when the input current is higher than a set current value, or when either or both of them are satisfied.

A fourth feature of the present invention is that the output error voltage amplifying circuit according to the first, second or third feature is an output current detection converter for detecting an output current by proportionally converting the output current into an output detection voltage. , A reference output voltage source for generating a reference output voltage,
The power supply device includes an output error voltage amplifier that differentially amplifies both of these voltages.

A fifth feature of the present invention is that the first, second, and
The input error voltage amplifier circuit according to the third or fourth feature is configured such that an input voltage dividing resistor that detects an input detection voltage, a reference input voltage source that generates a reference input voltage, and an input error that differentially amplifies these two voltages. It is a power supply device including a voltage amplifier.

A sixth feature of the present invention is that the first, second, and
The reference output voltage control circuit according to the third, fourth, or fifth feature is a power supply device including a control voltage dividing resistor that changes the reference output voltage according to the output voltage of the input error voltage amplifier, and a clamp diode. .

A seventh feature of the present invention is that the second or fourth
In the input error voltage amplification circuit of the feature of (3), the input current detection resistance that converts the input current into the input detection voltage and detects it, the reference input voltage source that generates the reference input voltage, and the input error voltage that differentially amplifies these two voltages. It is a power supply device including an amplifier.

An eighth feature of the present invention is the third or fourth aspect.
And a reference input voltage source for generating a reference input voltage, and an input error voltage amplification circuit for differentially amplifying both of these voltages. And a second input error voltage amplification circuit converts an input current into an input detection voltage and detects the input current detection resistance, a reference input voltage source generating a reference input voltage, and a difference between these two voltages. And a reference voltage control circuit for amplifying an input error voltage amplifier, wherein the reference output voltage control circuit changes the reference output voltage according to the output voltage of each of the first and second input error voltage amplification circuits. , And a clamp diode of each of the first and second input error voltage amplifiers.

The ninth feature of the present invention is that the fourth, fifth, and
The output current detection converter in the sixth, seventh, or eighth characteristics is a power supply device in which an output current detection converter immediately after that is connected to an inverter for converting DC power into AC power.

[0020]

According to the present invention, since the above-described means has been taken, when the output capacity of the fuel cell or the like used in the DC power generator is deteriorated due to aging or overload, the input voltage becomes lower than the set voltage. Alternatively, even if the input current exceeds the set current, the power supply detects the input voltage or current and decreases the output current while keeping the output power of the power supply above a certain level. It can be utilized to the maximum extent, and the decrease in the capacity of the DC generator can be detected by detecting the decrease in the current in the load.

Further, even when a converter is connected as a load, the output current is reduced while keeping the supplied power at a certain value or more, so that the converter can detect the decrease in the input current and limit the output power. Become.

[0022]

(First Embodiment) A first embodiment of the present invention will be described in detail with reference to the drawings. 1 is a circuit configuration diagram showing a first embodiment of the present invention, FIG. 2 is a reference voltage-input error voltage amplifier characteristic diagram of an output error voltage amplifier in the same example, FIG.
5 is an output current-power supply device input voltage correlation characteristic diagram in the same example, FIG. 4 is an input voltage / input power-power supply device input current correlation characteristic diagram in the same example, FIG.
FIG. 3 is a characteristic diagram of output current / input power-output voltage correlation of the power supply device in the same example.

In the figure, A1 is the power supply device of this embodiment, 1 is a direct current generator such as a fuel cell, 2 is a load, 3 is a main circuit / control circuit, 4 is an output current detection converter, and 5 is an output error voltage. Amplifier, 6 is a reference output voltage source, 7 and 8 are input voltage dividing resistors,
9a is an input error voltage amplifier, 10a is a reference input voltage source,
Reference numerals 11 and 12 are control voltage dividing resistors, and 13 is a clamp diode. The same elements as those in the conventional example are designated by the same reference numerals.

In the present embodiment shown in FIG. 1, the output of the DC power generator 1 such as a fuel cell is connected to the input of the power supply A1, and the output of the power supply A1 is connected to the load 2. The main circuit / control circuit 3 is composed of a dropper circuit, a switching power supply circuit, or the like.

In the power supply device A1 of this embodiment, the output error voltage amplifier circuit B outputs the output current Io to the output detection voltage Vo.
An output current detection converter 4 for proportional conversion to s for detection, a reference output voltage source 6 for generating a reference output voltage Vor, and an output error voltage amplifier 5 for differentially amplifying both of these voltages are provided. The voltage amplifier circuit C has an input detection voltage V
The input voltage dividing resistors 7 and 8 for detecting is, the reference input voltage source 10a for generating the reference input voltage Vir, and the input error voltage amplifier 9a for differentially amplifying both of these voltages are provided. The circuit D is composed of control voltage dividing resistors 11 and 12 and a clamp diode 13 that change the reference output voltage Vcr according to the output voltage Vc of the input error voltage amplifier 9a.

As the output current detection converter 4, a resistor connected in series with the load 2 for detecting a potential difference between both ends thereof, a DC current transformer, a Hall element type DC current transformer, or the like can be used. Hereinafter, it is assumed that the output current Io and the corresponding output detection voltage Vos have a proportional relationship of Vos = K · Io (K: constant).

Input detection voltage Vis (= R2 / (R1 + R2)) obtained by dividing the input voltage Vi of the power supply device A1 of the present invention by the input voltage dividing resistors 7 and 8 having resistance values R1 and R2, respectively.
-Vi) is input as the non-inverting input of the input error voltage amplifier 9a, and the reference input voltage Vir generated by the reference input voltage source 10a is input as the inverting input.

Since the specification of the present embodiment exhibits such a specific embodiment, when the input voltage Vi decreases, the input detection voltage Vis also decreases and the output voltage Vc of the input error voltage amplifier 9a decreases. As shown in FIG. 2, the relationship between the output voltage Vc of the input error voltage amplifier 9a and the reference voltage Vcr of the output error voltage amplifier 5 is the initial value R4 / (R3 + R4) .Vo.
It can be represented by a straight line of r and inclination R3 / (R3 + R4). When the reference voltage Vcr of the output error voltage amplifier 5 changes, the output current Io of the main circuit / control circuit 3 changes linearly according to the change of the reference voltage Vcr of the output error voltage amplifier 5.

Therefore, as shown in FIG. 3, the input voltage Vi is the set voltage value Vi '(= (R1 + R2) /R2.Vir).
When it further decreases, the output voltage Vc of the input error voltage amplifier 9a decreases, and the reference voltage Vc of the output error voltage amplifier 5 decreases.
By reducing r, the differential amplification control signal S becomes smaller, and the differential amplification control signal S controls the current of the main circuit / control circuit 3 configured by the dropper circuit or the switching power supply circuit to reduce the output current Io. To work.

Generally, the output impedance of the DC power generator 1 to which a fuel cell or the like is applied is high, and the output voltage decreases as the output current increases. Power supply A
FIG. 4 shows the relationship between the input voltage Vi of 1 and the input power Pi and the input current Ii. As the input current Ii of the power supply device A1 increases, the input impedance Vi decreases due to the output impedance of the DC power generator 1, and the input power Pi (= Vi · I).
i) increases.

In the power supply device A1, the input voltage Vi is the set voltage V
When it is higher than i ', the output current Io is maintained at a constant value. When the output voltage Vo of the power supply device A1 rises, the output power Po increases, so the input power Pi also increases accordingly. In the power supply device A1, the input current Ii increases to cope with the increase in the input power Pi.

First, as shown by the solid line in FIG. 4, before the output characteristics of the DC generator 1 deteriorate, when the input current increases to I1, the input voltage Vi decreases to the set voltage value Vi '. The input error voltage amplifier circuit C operates so as to decrease the output voltage Vc of the input error voltage amplifier 9a and decrease the output current Io when the input voltage Vi drops below the set voltage value Vi ', so the input voltage Vi is reduced. Set voltage value V
It is possible to maintain the input power Pi at a constant value P1 while maintaining i '.

Next, as shown by the broken line in FIG. 4, after the output characteristic of the DC generator 1 is deteriorated, the input voltage Vi is already at the set voltage value V when the input current increases to I2.
down to i '. Therefore, the input error voltage amplifier circuit C operates and the output current Io starts to decrease. Therefore, the input power Pi can be maintained at the constant value P2.

FIG. 5 shows the relationship between the output voltage Vo, the output current Io and the input power Pi of the power supply device A1. Output voltage V
Since the output power Po increases as o increases, the input power Pi of the power supply device A1 also increases in proportion to the output power Po.

First, as shown by the solid line in FIG. 5, before the output characteristics of the DC generator 1 deteriorate, the input power Pi increases and the input voltage Vi of the power supply A1 decreases to reach the set voltage value Vi '. . The input error voltage amplifier circuit C operates so as to decrease the output voltage Vc of the input error voltage amplifier 9a and decrease the output current Io when the input voltage Vi drops below the set voltage value Vi '.

Here, the input voltage Vi is set to the set voltage value V by increasing the gain of the input error voltage amplifier 9a.
It is possible to perform control such that the input power Pi is maintained at i ′ and the input power Pi is maintained at the constant value P1.

Next, as shown by the broken line in FIG. 5, after the output characteristic of the DC power generator 1 is deteriorated, the value of the input power Pi at which the input voltage Vi becomes equal to the set voltage value Vi 'changes from P1 to P2, Since the value of the output voltage Vo at which the output current Io starts to decrease becomes small, control is performed so that the input power Pi of the power supply device A1 is suppressed as compared with before the output characteristic deterioration.

(Second Embodiment) A second embodiment of the present invention will be described in detail with reference to the drawings. 6 is a circuit configuration diagram showing this embodiment, FIG. 7 is a characteristic diagram of output current / input current-output voltage correlation of the power supply device in the same example, and FIG. 8 is input voltage / input of the power supply device in the same example. It is a power-input current correlation characteristic diagram. In the following description, the same reference numerals are used for the same circuit elements as in the conventional example. In the figure, A2 is the power supply device of this embodiment, 9b is an input error voltage amplifier, 10b is a reference input voltage source, and 14 is an input current detection resistor.

In the power supply device A2 of the present invention, the output error voltage amplifier circuit B outputs the output current Io to the output detection voltage Vos.
An output current detection converter 4 for proportionally converting and detecting the output current, a reference output voltage source 6 for generating a reference output voltage Vor, and an output error voltage amplifier 5 for differentially amplifying both of these voltages. The amplifier circuit C ′ includes an input current detection resistor 14 that converts the input current Ii into an input detection voltage Vis ′ (= R5 · Ii) for detection, a reference input voltage source 10b that generates a reference input voltage Vir ′, and these. The reference output voltage control circuit D includes an input error voltage amplifier 9b that differentially amplifies both voltages, and the reference output voltage control circuit D changes the reference output voltage Vcr according to the output voltage Vc 'of the input error voltage amplifier 9b. 11, 12 and clamp diode 1
It consists of 3.

Since the specification of the present embodiment is such a concrete embodiment, the input current Ii of the power supply device A2 is the resistance value R.
By passing through the input current detection resistor 14 of No. 5, the voltage value Vis' (= R
5.Ii). If the set current value is Ii ′, the voltage of the reference input voltage source is Vir ′ (= R5 · I
When the input current Ii becomes larger than the set current value Ii ′ by setting i ′), the output voltage Vc ′ of the input error voltage amplifier 9b starts to decrease.

Output voltage Vc 'of the input error voltage amplifier 9b
Becomes lower than the reference output voltage Vor, the reference voltage Vcr of the output error voltage amplifier 5 decreases and the differential amplification control signal S
Becomes smaller, and the main circuit / control circuit 3 operates so as to reduce the output current Io. Therefore, as shown in FIG. 7, when the input current Ii becomes larger than the set current value Ii ′, it operates so as to reduce the output current Io of the power supply device A2.

By changing the gain of the input error voltage amplifier 9b, the rate of change of the output current Io with respect to the change of the input current Ii can be adjusted. Input error voltage amplifier 9b
Input voltage V of the power supply device A2 when the gain of the
FIG. 8 shows the relationship between i and the input current Pi and the input current Ii. By increasing the gain of the input error voltage amplifier 9b, the output current Io can be changed so that the input current Ii of the power supply device A2 maintains the set current value Ii ′, and thus even if the output voltage Vo rises. The output power Po is maintained at a constant value.

(Third Embodiment) A third embodiment of the present invention will be described in detail with reference to the drawings. FIG. 9 is a circuit configuration diagram showing this embodiment. In the following description, the same reference numerals are used for the same circuit elements as those in the conventional example and the first and second embodiments.
In the figure, A3 is a power supply device of this embodiment, and 13a and 13b are clamp diodes.

In the power supply device A3 of the present invention, the output error voltage amplifier circuit B outputs the output current Io to the output detection voltage Vos.
The output current detection converter 4 that proportionally converts the voltage into the output current, the reference output voltage source 6 that generates the reference output voltage Vor, and the output error voltage amplifier 5 that differentially amplifies these two voltages. The input error voltage amplifier circuit Ca includes input voltage dividing resistors 7 and 8 that detect the input detection voltage Vis, a reference input voltage source 10a that generates the reference input voltage Vir, and an input error voltage amplifier that differentially amplifies these two voltages. The second input error voltage amplification circuit Cb includes an input current detection resistor 14 for converting the input current Ii into an input detection voltage Vis ′ (= R5 · Ii) for detection, and a reference input voltage Vir. The reference output voltage control circuit D'comprises a reference input voltage source 10b for generating the signal 'and an input voltage error amplifier 9b for differentially amplifying both voltages. Depending on the voltage Vc and the output voltage Vc of the second input error voltage amplifier 9b 'reference output voltage V
It is composed of control voltage dividing resistors 11 and 12 for changing cr and clamp diodes 13a and 13b.

Since the specifications of the present embodiment show such a concrete embodiment, when the input voltage Vi of the power supply device A3 becomes lower than the set voltage value Vi ', the input error voltage amplifier 1
The output voltage Vc of 0a decreases, the reference voltage Vcr of the output error voltage amplifier 6 decreases, and the differential amplification control signal S decreases, and the differential amplification control signal S causes the main circuit formed by the dropper circuit or the switching power supply circuit. The circuit / control circuit 3 controls the current and operates to reduce the output current Io. Therefore, when the input voltage Vi becomes lower than the set voltage value Vi ', it operates so as to reduce the output current Io of the power supply device A3.

Further, the input current Ii of the power supply device A3 passes through the input current detecting resistor 14 having the resistance value R5, so that the potential difference across the input current detecting resistor 14 is converted into the voltage value Vis'. The reference input voltage of the reference input voltage source 10b is V
When the input current Ii becomes larger than the set current value Ii 'by setting ir', the output voltage Vc 'of the input error voltage amplifier 9b starts to decrease.

Output voltage Vc 'of the input error voltage amplifier 9b
Is lower than the reference output voltage Vor, the reference voltage Vcr of the output error voltage amplifier 5 is lowered, the differential amplification control signal S is reduced, and the main circuit / control circuit 3 operates to lower the output current Io. Therefore, when the input current Ii becomes larger than the set current value Ii ′, the output current Io of the power supply device A3 is operated to decrease. Therefore, in the present embodiment, it is possible to detect the changes in the input voltage Vi and the input current Ii of the power supply device A3 at the same time and control the power supplied to the load 2.

In the first, second and third embodiments, the output current I of the power supply devices A1, A2 and A3 is set.
Although the reference voltage Vcr of the output error voltage amplifier 5 is changed as a means for decreasing o, the same effect can be obtained by dividing the output detection voltage Vos corresponding to the output current Io and changing the voltage division ratio. It goes without saying that you can do it.

Further, in the first embodiment, the second embodiment and the third embodiment, the case where the input and output of the power supplies A1, A2 and A3 are not insulated is explained.
When electrically isolating the input / output of A1, A2 and A3, the input / output of the main circuit / control circuit 3 and the output current detection converter 4 are insulated using a transformer or the like, and the voltage of the input / output is Alternatively, it goes without saying that the current can be detected by using a photocoupler, an insulating amplifier, a Hall element, or the like.

In the first, second, and third embodiments, an inverter α for converting DC power into AC power is provided immediately after the output current detection converter 4 of the power supply devices A1, A2, and A3. By connecting with, the power supply device can be applied to an AC load.

[0051]

As described above, according to the present invention, by detecting the input voltage or the input current of the power supply device and reducing the output current, the performance of the DC power generation device in which the output capacity changes due to aging deterioration or the like is deteriorated. The maximum output capacity can be obtained without

Particularly, when a fuel cell or the like is used as a DC power generator, the maximum power capacity that can be taken out decreases due to deterioration over time, but it is possible to always supply the maximum power to the load by detecting a decrease in the maximum power capacity value. It is possible to use the maximum capacity at all times, and it exhibits excellent economic efficiency and efficiency.

Further, in the load, the decrease in the power capacity of the DC generator can be detected by detecting the decrease in the current. Even when the converter is connected as the load, the output current is decreased while keeping the supplied power at the maximum. Therefore, the power supply can be sustained without stopping the converter.
Further, the converter detects the decrease in the input current, thereby limiting the output power and thereby preventing a power failure accident, which shows excellent reliability and usefulness.

Furthermore, by connecting an inverter for converting DC power to AC power, not only DC power but also AC power can be supplied to the load, and regardless of the type of load, it is excellent in versatility and usefulness. Exert its abilities.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a power supply device A1 showing a first embodiment of the present invention.

FIG. 2 is a correlation characteristic diagram of the reference voltage Vcr of the output error voltage amplifier 5 and the output voltage Vc of the input error voltage amplifier 9a in the above.

FIG. 3 is an output current Io-input voltage Vi correlation characteristic diagram in the above.

FIG. 4 is a correlation characteristic diagram of the input voltage Vi, the input power Pi and the input current Ii in the above.

FIG. 5 is a correlation characteristic diagram of the output current Io, the input power Pi, and the output voltage Vo in the above.

FIG. 6 is a circuit configuration diagram of a power supply device A2 showing a second embodiment of the present invention.

FIG. 7 is a correlation characteristic diagram of output current Io / input current Ii-output voltage Vo in the above.

FIG. 8 is a correlation characteristic diagram of the input voltage Vi, the input power Pi and the input current Ii in the above.

FIG. 9 is a circuit configuration diagram of a power supply device A3 showing a third embodiment of the present invention.

FIG. 10 is a circuit configuration diagram of a conventional power supply device.

[Explanation of symbols]

 A, A1, A2, A3 ... Power supply device B ... Output error voltage amplification circuit C, C '... Input error voltage amplification circuit Ca ... First input error voltage amplification circuit Cb ... Second input error voltage amplification circuit D, D '... Reference output voltage control circuit 1 ... DC generator 2 ... Load 3 ... Main circuit / control circuit 4 ... Output current detection converter 5 ... Output error voltage amplifier 6 ... Reference output voltage source 7, 8 ... Input voltage dividing resistance 9a, 9b ... Input error voltage amplifier 10a, 10b ... Reference input voltage source 11, 12 ... Control signal voltage dividing resistor 13, 13a, 13b ... Clamp diode 14 ... Input current detection resistor Ii ... Power source input current Ii '... Setting Current value Io ... Output current of power supply device Po ... Output power of power supply device S ... Differential amplification control signal Vc ... Output voltage of input error voltage amplifier 9a Vc '... Output voltage Vc of input error voltage amplifier 9b r ... Reference voltage of output error voltage amplifier 5 Vi ... Input voltage of power supply device Vi '... Set voltage value Vir, Vir' ... Reference input voltage Vis, Vis' ... Input detection voltage Vo ... Output voltage of power supply device Vor ... Reference output Voltage Vos ... Output detection voltage α ... Inverter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kumihito Tateda 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (9)

[Claims] 1. A power supply device for supplying stable power to a load by connecting to an output of a direct current generator such as a fuel cell, and a main circuit / control circuit and an output proportional to the output current of the main circuit / control circuit. An output error voltage amplifier circuit for comparing a detection voltage and a reference output voltage, amplifying the difference voltage and supplying the amplified difference voltage to the main circuit / control circuit, and an input for comparing the input detection voltage of the main circuit / control circuit with the reference input voltage. A power supply device comprising: an error voltage amplifier circuit; and a reference output voltage control circuit that changes the reference output voltage when the input detection voltage is lower than the reference input voltage. 2. A power supply device for supplying stable power to a load by connecting to an output of a direct current generator such as a fuel cell, and a main circuit / control circuit and an output proportional to the output current of the main circuit / control circuit. An output error voltage amplifier circuit that compares the detected voltage with a reference output voltage and amplifies the difference voltage to supply to the main circuit / control circuit, an input detection current of the main circuit / control circuit, and a reference input voltage corresponding thereto. And an output voltage control circuit that changes the reference output voltage when the input current is larger than a set current value. 3. A power supply device for supplying stable power to a load by connecting to an output of a DC power generator such as a fuel cell, and a main circuit / control circuit and an output proportional to the output current of the main circuit / control circuit. An output error voltage amplifier circuit for comparing the detected voltage and the reference output voltage, amplifying the difference voltage and supplying the amplified difference voltage to the main circuit / control circuit, and comparing the input detected voltage of the main circuit / control circuit with the reference input voltage. No. 1 input error voltage amplification circuit, a second input error voltage amplification circuit for comparing the input current of the main circuit and control circuit with a reference input voltage proportional thereto, and the case where the input voltage is lower than the set voltage value A power supply device, comprising: a reference voltage control circuit that changes the reference output voltage when either or both of a case where the current is larger than a set current value. 4. An output error voltage amplifier circuit, wherein an output current detection converter for converting an output current proportionally to an output detection voltage and outputting the output current, a reference output voltage source for generating a reference output voltage, and a differential amplification of these two voltages. 5. The power supply device according to claim 1, wherein the power supply device comprises an output error voltage amplifier. 5. An input error voltage amplifier circuit comprises an input voltage dividing resistor for detecting an input detection voltage, a reference input voltage source for generating a reference input voltage, and an input error voltage amplifier for differentially amplifying these two voltages. The power supply device according to claim 1 or 4, wherein: 6. The reference output voltage control circuit comprises a control voltage dividing resistor for changing the reference output voltage according to the output voltage of the input error voltage amplifier, and a clamp diode. The power supply device according to 3, 4, or 5. 7. An input error voltage amplifier circuit, an input current detection resistor for converting an input current into an input detection voltage for detection, a reference input voltage source for generating a reference input voltage, and an input for differentially amplifying both of these voltages. 5. The power supply device according to claim 2, comprising an error voltage amplifier. 8. A first input error voltage amplifying circuit includes an input voltage dividing resistor for detecting an input detection voltage, a reference input voltage source for generating a reference input voltage, and an input error voltage for differentially amplifying these two voltages. The second input error voltage amplification circuit is composed of an amplifier, and the second input error voltage amplification circuit converts an input current into an input detection voltage and detects the input current detection resistance, a reference input voltage source for generating a reference input voltage, and both of these voltages. The reference output voltage control circuit includes an input error amplifier for differential amplification, and a reference voltage dividing resistor for changing the reference output voltage according to the output voltage of each of the first and second input error voltage amplification circuits. 5. The power supply device according to claim 3, further comprising a clamp diode of each of the first and second input error voltage amplifiers. 9. The power supply device according to claim 4, wherein the output current detection converter is connected immediately after that with an inverter for converting DC power into AC power.