JP3082849B2 - Uninterruptible power system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an uninterruptible power supply (UPS) capable of improving a waveform, improving a power factor, and adjusting a voltage.

[0002]

2. Description of the Related Art An uninterruptible power supply used in a computer system or the like includes a converter for converting AC to DC, a storage battery charged by the output of the converter, and an inverter for converting the output of the converter or the output of the storage battery to AC. It is composed of Since this type of uninterruptible power supply has a storage battery, when the AC power supply is in a power outage state or a low voltage state, the DC of the storage battery is converted into AC by an inverter to supply power to the load.

[0003]

When the load current includes a harmonic current component and a reactive current component, it is necessary to improve the waveform and power factor of the AC input. Waveform improvement and power factor improvement technologies already exist,
Providing independent waveform and power factor correction devices increases the cost of the power supply. In addition, when the storage battery is charged by the converter and the inverter is driven according to the conventional technology, the power capacity of the converter and the inverter needs to be set to be equal to or larger than the power capacity of the load. Power loss.

An object of the present invention is to reduce the cost and size of an uninterruptible power supply capable of improving a waveform, improving a power factor, and adjusting a voltage.

[0005]

In order to achieve the above object, the present invention provides an AC power supply terminal for supplying AC power to a load, a series circuit of first and second capacitors ,
Is connected between the load and the series circuit of the first and second capacitors, said with the compensation current generated for performing improved reduction and power factor of the harmonic component first and second con <br A first operation for charging a capacitor and a second operation for converting a DC voltage of the first and second capacitors into an AC voltage can be selectively performed. When the AC voltage is supplied from the AC power supply terminal to the load, the first converter is controlled so that the first operation occurs, and the AC power supply terminal Connected to a first control circuit for controlling the first converter so that the second operation occurs when no AC voltage is supplied to the load; and a series circuit of the first and second capacitors. And also connected between the AC power supply terminal and the load, A second converter configured to convert a DC voltage of the first and second capacitors into an AC voltage for adjusting the voltage of the load; and a second converter configured to convert the voltage of the load to a desired value. An uninterruptible power supply device comprising: a second control circuit for controlling a second converter;
With respect to the series circuit of the first and second capacitors
Series circuit of first and second switches connected in parallel
And connected in reverse parallel to the first and second switches.
First and second diodes, and a first filter
The reactor, the first filter capacitor, and the tap
And a coil having the coil with respect to the load
Connected in parallel, and the tap of the coil is connected to the first filter.
The first and second switches via a reactor for luta
And one end of the coil is connected to the first
And a second capacitor interconnect point,
The filter capacitor of No. 1 is the tap and the other end of the coil
And an uninterruptible power supply characterized by being connected between the It is desirable to provide a storage battery to extend the power supply available time during a power outage. Further, as described in claims 3 to 10 , the second converter can be constituted by a half-bridge type circuit of the first and second inverter switches. Also,
As described in claims 3 to 5 , a series circuit of the first and second capacitors having a function as a DC power supply is shared by the first converter of the half-bridge type and the second converter of the half-bridge type. be able to. The power supply as shown in claim 11, the load can be the first and second converters each 3-phase circuits.

[0006]

According to the present invention, since the capacitor functions as a DC power source for both the first and second converters, the DC side circuit of the first and second converters is simplified. In addition, the size and cost of the uninterruptible power supply can be reduced. Further, since the second converter is configured to generate only a change in the voltage of the load, the power capacity of the second converter can be made smaller than the power capacity of the load.
As a result, the size, cost, and loss of the uninterruptible power supply can be reduced. Since the waveform improvement and the power factor improvement are performed by the first converter, reduction in power loss and suppression of harmonic noise are achieved. Further, it constitutes a first transducer as shown in claim 1 in a half-bridge type circuit,
Further, when the second converter is configured as a half-bridge circuit as described in claims 4 to 10 , downsizing and cost reduction of the first and second converters are achieved. Claims 3 to
As shown in FIG. 5, when the series circuit of the first and second capacitors is shared by the first and second converters of the half-bridge type, further reduction in size and cost can be achieved.

[0007]

[Basic configuration] Before describing the embodiments of the present invention,
In order to facilitate understanding of the invention, the applicant has
An uninterruptible power supply having the same principle as the present invention is shown in FIGS.
It will be described in the light of the above.

The uninterruptible power supply shown in FIG.
0 Hz or 60 Hz, AC 100 V commercial AC power supply 1
And second AC power supply terminals 2a, 2b connected to
And first and second output terminals 4a and 4b to which a load 3 such as a personal computer is connected, and a first converter 5 having a waveform and power factor improvement function and an inverter (DC-AC conversion) function. , A first control circuit 6 for this first converter 5
A second converter 7 having an output voltage adjusting function, a second control circuit 8 for the second converter 7, and a DC power supply used for improving a waveform and a power factor as well as being used as a DC power supply. Power switch comprising a capacitor 9, a storage battery 10, first and second current detectors 11, 12, an AC output voltage detector 13, a DC voltage detector 14, an input voltage detector 15, and a triac. 16 and a power switch control and power failure detection circuit 17.

The first converter 5 has a pair of lines 18, 19
Are connected to the first and second output terminals 4a and 4b. That is, the first converter 5 is connected to the load 3 in parallel. The first converter 5 generates a compensation current for canceling a harmonic current component and a reactive current component generated based on the load 3 during a non-power failure (normal operation) and obtaining a sine wave current in phase with the AC power supply voltage. The first operation that occurs and the second operation that converts the DC voltage of the capacitor 9 and the storage battery 10 into an AC voltage and supplies the AC voltage to the load 3 at the time of a power failure can be performed. Further, the first converter 5 has a function of charging the capacitor 9 and the storage battery 10 to a constant voltage in a normal state. This first converter 5
Will be described later in detail with reference to FIG.

A first control circuit 6 controls a first converter 5 so as to generate a compensation current, and a first control circuit 6 converts a DC voltage of the capacitor 9 and the storage battery 10 into an AC voltage. And a circuit for controlling the converter 5 of the input voltage detector 1 connected to the first converter 5 by lines 20, 21, 22, 23 and the input voltage detector 1 by line 24.
5, connected to the power switch control and power failure detection circuit 17 by a line 25, connected to the first current detector 11 by a line 26, connected to the second current detector 12 by a line 26, and connected to a line 28 Is connected to the output voltage detector 13 and is connected to the DC voltage detector 14 by a line 29. The details of the first control circuit 6 will be described later with reference to FIGS. 3, 4, and 5.

The second converter 7 is an inverter circuit connected to the capacitor 9 and the storage battery 10 and connected between the first AC power supply terminal 2a and the first output terminal 4a.
The DC voltage of the capacitor 9 and the storage battery 10 is converted into an AC voltage, and the output voltage is combined (added or subtracted) with the voltage of the AC power supply 1. The details of the second converter 7 will be described later.

A second control circuit 8 controls lines 30, 31, 3 for controlling the conversion switch of the second converter 7.
2, 33 connected to the second converter 7 and connected to the output voltage detector 13 by a line 33 to control the AC output voltage constant, and also generates a reference sine wave synchronized with the power supply 1. Connected to the input voltage detector 15 by a line 35. Details of the second control circuit 8 will be described later.

The first current detector 11 is for detecting a current flowing through the load 3 and is electromagnetically coupled to an AC power supply line between the first AC power supply terminal 2a and the first output terminal 4a. Have been. The first current detector 11 detects electromagnetic load between the connection point P1 of the output line 18 of the first converter 5 to the AC power supply line and the first output terminal 4a in order to detect only the load current. Have been. The second current detector 12 detects the compensation current supplied by the first converter 5 and is electromagnetically coupled to the output line 18 of the first converter 5. The output voltage detector 13 is connected to the first and second output terminals 4a and 4b for detecting the voltage of the load 3 whose rated voltage is set to 100V. The DC voltage detector 14 is connected between these terminals to detect the voltage of the capacitor 9 and the storage battery 10. The input voltage detector 15 is connected between the first and second AC power supply terminals 2a and 2b.

The power switch 16 is connected to the first AC power terminal 2.
a and the second converter 7. The power switch control and power failure detection circuit 17 controls the power switch 16 to be in the ON state when the voltage is normally supplied from the AC power supply 1, and when the power supply from the AC power supply 1 is stopped or when the power supply voltage is low. Then, the power switch 16 is turned off and a signal indicating a power failure is generated on the line 25. For this reason, the power switch control and power failure detection circuit 17 includes the first and second AC power terminals 2a and 2b.
And the control terminal of the power switch 16 and the first control circuit 6.

FIG. 2 shows the first and second converters 5, 7 in detail. The first converter 5 comprises first, second, third and fourth switches Q1, Q2 comprising transistors.
, Q3, Q4, first, second, third and fourth diodes D1, D2, D3, D4, a first filter reactor (inductance element) L1, and a first filter capacitor C1. . First and second switches Q
1, Q2 and a third and fourth switch Q3,
The series circuit of Q4 is connected in parallel with the capacitor 9 and the storage battery 10. The first, second, third and fourth diodes D1, D2, D3 and D4 are connected in anti-parallel to the first, second, third and fourth switches Q1, Q2, Q3 and Q4. . First and second switches Q1, Q2
Is connected to the first output terminal 4a via the first filter reactor L1 and the line 18, and the third
And the interconnection point of the fourth switches Q3 and Q4 is line 1
9 is connected to the second output terminal 4b. First
Is connected to first and second output terminals 4a and 4b via lines 18 and 19. That is, the first filter capacitor C1 connects the first filter reactor L1 between the interconnection point of the first and second switches Q1 and Q2 and the interconnection point of the third and fourth switches Q3 and Q4. Connected through. The first to fourth switches Q1 to Q4 connected in a bridge type and the first
The fourth to fourth diodes D1 to D4 perform a compensation current supply operation (first operation) and an inverter operation (second operation).
Also, during the compensation current supply operation, the capacitor 9 and the storage battery 1
Charge 0 to constant voltage. First filter reactor L
1 and a first filter capacitor C1 connect the first to fourth switches Q1 to Q4 to the AC power supply 1
Harmonic components generated by turning on and off at a repetition frequency (for example, 20 kHz) sufficiently higher than the frequency (for example, 50 Hz or 60 Hz) are removed.

The second converter 7 includes first, second, third and fourth inverter switches S 1, which comprise transistors for forming a well-known bridge type inverter circuit.
S2, S3, S4, first, second, third, and fourth parallel diodes D11, D12, D13, D14, a second filter reactor (inductance element) L2, and a second filter capacitor C2 And a transformer Tr having a primary winding N1 and a secondary winding N2 electromagnetically coupled to each other, and an input voltage stabilizing capacitor C3. First and second
Series circuit of the inverter switches S1, S2 and the third
A series circuit of the fourth inverter switches S3 and S4 is connected in parallel to the capacitor 9 and the storage battery 10. Diodes D11, D12, D13 and D14 are connected in reverse direction to switches S1, S2, S3 and S4, respectively. The first and second inverter switches S1,
A second filter capacitor L2 is connected between the interconnection point of S2 and the interconnection point of the third and fourth inverter switches S3 and S4 via a second filter reactor L2.
Is connected. The primary winding N1 of the output transformer Tr is connected in parallel to the second filter capacitor C2. The secondary winding N2 is connected in series between the power switch 16 and the first output terminal 4a. Accordingly, the voltage of the secondary winding N2 is combined (added or subtracted) with the voltage of the power supply 1 and used for adjusting the voltage between the output terminals 4a and 4b. The second converter 7 has a rated voltage (100 V) of about 2
It has a voltage adjustment capability of 0%. The filter circuit composed of the second filter reactor L2 and the second filter capacitor C2 sets the first to fourth inverter switches S1 to S4 at a repetition frequency sufficiently higher than the frequency of the power supply 1 (for example, 20 kHz). ) To remove the harmonic components generated by turning on and off.

FIG. 3 schematically shows the first control circuit 6 of FIG. The first control circuit 6 roughly includes a compensation current control circuit 36, an inverter control circuit 37, and a switching circuit 38. The compensation current control circuit 36 is connected to the lines 24, 26, 2
The first to fourth switches Q1 to Q4 of the first converter 5 are adapted to supply a compensation current for making the currents at the power supply terminals 2a and 2b into a sine wave in phase with the power supply voltage based on the signals at 7 and 29. A signal for controlling .about.Q4 is generated. The inverter control circuit 37 converts the DC voltage of the capacitor 9 and the storage battery 10 into an AC voltage based on the signals on the lines 24 and 28 so as to convert the first to fourth switches Q to Q of the first converter 5.
A signal for controlling 1 to Q4 is generated. Switching circuit 3
8 denotes four compensation control signal selection switches 39a, 39b,
39c, 39d and four inverter control signal selection switches 40a, 40b, 40c, 40d. Compensation control signal selection switches 39a, 39b, 39c, 39d
Is turned on when the power failure detection line 25 indicates the non-power failure state, selects the signals of the four output lines 41a, 41b, 41c and 41d of the compensation current control circuit 36 and switches Q1, Q2, Q3 and Q4. Control signal lines 20, 2
1, 22, and 23. The inverter control signal selection switches 40a, 40b, 40c, and 40d are turned on when the power failure detection line 25 indicates a power failure state, and the four output lines 42a, 42b,
42c and 42d, and switches Q1, Q2,
Q3 and Q4 are sent to control signal lines 20, 21, 22, and 23, respectively. The control signal lines 20, 21, 22, and 23 correspond to the first, second, third and fourth switches Q1, Q2,
Connected to the control terminals (bases) of Q3 and Q4.

FIG. 4 shows details of the compensation current control circuit 36 shown in FIG.
This will be described with reference to FIG. This compensation current supply circuit 3
6 is a reference sine wave voltage generator 43 as shown in FIG.
Multiplier 44, reference voltage source 45, first subtractor 46
, A proportional integrator 47, a second subtractor 48, a third subtractor 49, a comparator 50, a first waveform shaping circuit 50a, a triangular wave generator 51, a NOT circuit 52, a second And a waveform shaping circuit 52a. The reference sine wave generator 43 is connected to the input voltage detector 15 shown in FIG. 1 by a line 24, and generates a reference sine wave voltage E0 having a predetermined amplitude shown in FIG. Are sent to the multiplier 44. The reference voltage source 45 is shown in FIGS.
A reference voltage corresponding to the target voltage of the capacitor 9 and the storage battery 10 is generated. The first subtractor 46 has a reference voltage source 45.
And the DC voltage detection line 29, and the reference voltage source 4
5 and a DC detection voltage obtained from the voltage detector 14 shown in FIG. 1, that is, an error output is generated. The proportional integrator 47 includes an operational amplifier 47a and three resistors 47b, 4
7c and 47d, and multiplies and integrates the output of the first subtractor 46 with a predetermined gain to generate a voltage control signal for controlling the voltage of the capacitor 9 and the storage battery 10 to be constant. The proportional integrator 47 is configured to respond to a frequency lower than the frequency of the power supply 1 (50 Hz or 60 Hz). Therefore, the voltage control signal output from the proportional integrator 47 is a signal that changes slowly and does not include a harmonic component based on the on / off of the switches Q1 to Q4. The multiplier 44 multiplies the reference sine wave voltage E0 shown in FIG. 7 by the voltage control signal obtained from the proportional integrator 47, and
The voltage E1 shown in FIG. That is, the multiplier 44 modulates the amplitude of the reference sine wave voltage E0 with the voltage control signal, and generates a sine wave voltage E1 having both DC voltage control information and reference sine wave information. One input terminal of the second subtractor 48 is connected to the multiplier 44, and the other input terminal is connected to the first current detector 1 of FIG.
1 connected. Therefore, the second subtractor 48
Is a signal E corresponding to the load current obtained from the first current detector 11 from the sine wave voltage E1 obtained from the multiplier 44.
2 is subtracted to output a compensation command signal E3. In FIG. 7, since the detection signal E2 corresponding to the waveform of the current flowing through the load 3 is illustratively shown as a square wave voltage, the compensation command signal E3 obtained from the second subtractor 48 has a sine wave peak. And a voltage waveform having a concave portion in the vicinity thereof. Note that the same compensation as in FIG. 7 can be performed when the load current detection signal E2 has a waveform other than the square wave shown in FIG. 7, or when a phase difference occurs between the load current detection signal E2 and the reference sine wave. Operation occurs. One input terminal of the third subtractor 49 is connected to the output terminal of the second subtractor 48, and the other input terminal is connected to the second current detector 27 by the line 27. Accordingly, the third subtractor 49 is provided with a compensation command signal E3 obtained from the second subtractor 48 and a detection signal E4 indicating the actual compensation current obtained from the second current detector 12.
And outputs a signal E5 indicating the difference. Now, the compensation command signal E
Assuming that a compensation close to 3 is performed, the compensation current detection signal E4 becomes a voltage having a waveform close to the compensation command signal E3 as shown in FIG. The comparator 50 compares the error signal E5 obtained from the third subtractor 49 with the triangular wave generator 5
The binary output voltage E7 shown in FIG. 7 is generated by comparing with the triangular wave voltage E6 obtained from FIG. The triangular wave generator 51 operates at the frequency of the voltage of the AC power supply 1 (for example, 50 Hz or 60H).
z), a repetition frequency sufficiently higher than (e.g., 20 kHz)
In z), a triangular wave voltage E6 is generated. In FIG. 7, the triangular wave voltage E6 is illustratively shown at a low repetition frequency. The comparison between the error signal E5 and the triangular wave voltage E6 is performed in a state where the center values of both waveforms are matched, and the output E7 of the comparator 50 is a binary signal shown in FIG. In this embodiment, the output E7 of the comparator 50 is sent to the lines 41a and 41d via the first waveform shaping circuit 50a, and is used as a control signal for the first and fourth switches Q1 and Q4. The output E8 of the NOT circuit 52 which forms the inverted signal of E7 is supplied to the second waveform shaping circuit 52a.
To the lines 41b and 41c via the second and third lines.
Are used as control signals for the switches Q2 and Q3. Therefore, in the following description, E7 and E8 may be called control signals. The first waveform shaping circuit 50a slightly narrows the pulse width of the output E7 of the comparator 50, and the second waveform shaping circuit 52a slightly narrows the pulse width of the output E8 of the NOT circuit 52. . The first and second waveform shaping circuits 50a and 52a include first and second switches Q1 and Q2, and third and fourth switches Q1 and Q2.
3. It has a function to prevent Q4 from being turned on at the same time by the storage action of carriers.

[0019]

[Compensation Operation and Charging Operation] When the switches 39a, 39b, 39c and 39d of the switching circuit 38 shown in FIG. 3 are turned on, the output E7 of the comparator 50 and the output E8 of the NOT circuit 52 shown in FIG. The first to fourth switches Q1 to Q4 are turned on and off. First converter 5
Are controlled based on the output of the compensation current control circuit 36, the current Ir 'for removing the ineffective component Ir of the current of the load 3 is connected to the output line 18 of the first converter 5. A current Ih 'for removing the harmonic component Ih of the current of the load 3 and an effective current I0 for charging the capacitor 9 and the storage battery 10 flow. To explain this in more detail, the load current I1 is represented by a composite I1 = Ie + Ir of the active current component Ie and the reactive current component Ir. Also,
The load current I1 is represented by a combination of a fundamental component If and a harmonic component Ih, I1 = If + Ih. When the current flowing between the connection points P1 and P2 between the AC power supply 1 and the first converter 5 in FIGS. 1 and 2 is made only the active current component Ie and the fundamental wave component If, the reactive current component of the load current I1 An ineffective compensation current Ir 'for canceling Ir and a harmonic compensation current Ih' for canceling a harmonic component Ih of the load current I1 are supplied from the first converter 5. During the period from t1 to t2 in FIG. 7 during the positive half cycle of the voltage of the power supply 1, the first and fourth switches Q1, Q4 are off, and the second and third switches Q2, Q2,
When Q3 is turned on, a closed circuit of the power supply 1, the power supply switch 16, the secondary winding N2, the first filter reactor L1, the first diode D1, and the third switch Q3 is formed. A closed circuit of the power switch 16, the first filter reactor L1, the second switch Q2, and the fourth diode D4 is formed. Thereby, a compensation current corresponding to the compensation current detection signal E4 shown in FIG. 7 can be supplied from the first converter 5 to the AC power supply line, and the reactive current component Ir and the harmonic current component of the current I1 of the load 3 can be supplied. Ih can be removed. Accordingly, the current between the power supply 1 and the connection points P1 and P2 is substantially only the effective current and the fundamental wave current, the power factor and the current waveform are improved, and the power loss and harmonic noise are reduced. Become. FIG.
During the period from t2 to t3, the first and fourth switches Q1,
Since Q4 is turned on, the second and third switches Q
2, Q3 turns off, power supply 1, power switch 1
6, secondary winding N2, first filter reactor L1,
A closed circuit including the first diode D1, the capacitor 9 and the storage battery 10, and the fourth diode D4 is formed, and the capacitor 9 and the storage battery 10 are charged. Power supply 1
The first and fourth switches Q and Q4 are turned off during the period from t4 to t5 in FIG.
The second and third switches Q2 and Q3 are turned on.
As a result, the power supply 1, the third diode D3, the capacitor 9 and the storage battery 10, the second diode D2, the first filter reactor L1, the secondary winding N2, and the power switch 1
6 are formed. Thereby, t4 to t5
In the period, the charging operation of the capacitor 9 and the storage battery 10 occurs as in the period from t2 to t3. During the period from t5 to t6 in the negative cycle, the first and fourth switches Q1 and Q4 are turned on, and the second and third switches Q2 and Q3 are turned off. As a result, a closed circuit including the power supply 1, the fourth switch Q4, the second diode D2, the first filter reactor L1, the secondary winding N2 and the power supply switch 16, the power supply 1, the third diode D
3. A closed circuit comprising the first switch Q1, the first filter reactor L1, the secondary winding N2, and the power switch 16 is formed. As a result, an operation of supplying a compensation current occurs during the period from t5 to t6, as in the period from t1 to t2. The ratio of the period between t1 and t2 and the period between t2 and t3, and the ratio between the period between t4 and t5 and the period between t5 and t6 remove the harmonic current component and the reactive current component of the current of the load 3, and reduce the voltages of the capacitor 9 and the storage battery 10. It is controlled to keep it constant.

[0020]

[Inverter Control Circuit] FIG. 5 shows the inverter control circuit 37 of FIG. 3 in detail. The inverter control circuit 37 includes a reference sine wave generator 53, a subtractor 54, a comparator 55, a waveform shaping circuit 55a, a triangular wave generator 56, and a NOT for operating the first converter 5 as an inverter.
8 includes a circuit 57 and a waveform shaping circuit 57a.
It operates as shown in FIG. The reference sine wave generator 53 is connected to the input voltage detector 15 of FIG. 1 by a line 24, and when the power supply 1 is normal, generates a reference sine wave voltage synchronized with this AC voltage, and the power supply 1 is in a power failure state. At this time, a reference sine wave voltage E10 continuously arranged with respect to the normal reference sine wave voltage is generated as shown in FIG. One input terminal of the subtractor 54 is connected to the reference sine wave generator 53, and the other input terminal is connected to the output voltage detector 13 of FIG. Accordingly, the subtractor 54 generates an error voltage E12 between the reference sine wave voltage E0 and the output detection voltage E11 as shown in FIG. The comparator 55 is connected to the subtractor 54 and the triangular wave generator 56, and compares the error voltage E12 and the triangular wave voltage E13 to generate a binary output voltage E14 shown in FIG. 8, that is, a PWM (pulse width modulation) waveform. I do. The triangular wave generator 56 generates a triangular wave voltage E13 at a repetition frequency (for example, 20 kHz) sufficiently higher than the voltage of the power supply 1 and the frequency of the reference sine wave voltage E0 (for example, 50 Hz or 60 Hz), like the triangular wave generator 51 of FIG. I do. As is clear from FIG. 8, the center level of the error voltage E12 matches the center level of the triangular wave voltage E13. The output E14 of the comparator 55 is a waveform shaping circuit 55a.
Through the lines 42a, 42d and is used to control the first and fourth switches Q1, Q4 of the first converter 5. NOT circuit 57 connected to comparator 55
Generates an output E15 obtained by inverting the output E14 of the comparator 55 as shown in FIG. The output voltage E15 of the NOT circuit 57 is supplied to the lines 42b, 4b via the waveform shaping circuit 57a.
2c and is used to control the second and third switches Q1, Q2. The waveform shaping circuit 55a slightly narrows the pulse width of the output E14 of the comparator 55, and the waveform shaping circuit 57a outputs the output E14 of the NOT circuit 57.
The width of the 15 pulses is slightly reduced. The waveform shaping circuits 55a and 57a of FIG.
a, 52a are provided for the same purpose. The output E14 of the comparator 55 and the output E15 of the NOT circuit 57
May be hereinafter referred to as a switch control signal. When the power supply 1 is in a power failure state or a state where the voltage is lower than a predetermined value,
This power failure state is detected by the power supply switch control and power failure detection circuit 17 of FIG. 1, the power supply switch 16 is controlled to be turned off, the switches 39a to 39d of FIG. 3 are controlled to be turned off, and the switches 40a to 40d are turned on. Controlled. As a result, the switch control signal of the inverter control circuit 37 is supplied to the bases of the switches Q1 to Q4 of the first converter 5 via the switches 40a to 40s and the lines 20 to 23. When the first to fourth switches Q1 to Q4 of the first converter 5 are turned on / off according to the control signals E14 and E15 shown in FIG. 8 during a power failure, the first converter 5 The voltage is converted into an AC voltage having the same frequency as that of the power supply 1 and supplied to the load 3. Since the inverter control circuit 37 performs feedback control on the switches Q1 to Q4 so as to keep the output voltage E11 constant, an AC voltage can be stably supplied to the load 3 even during a power failure. When the power supply 1 returns from the power failure state or the voltage drop state to the normal state, the power switch 16 is turned on, the first converter 5 returns to the compensation current supply mode operation, and the second converter 7 performs the voltage regulation. Start operation.

[0021]

Second control circuit A second control circuit 8 for operating the second converter 7 as an inverter includes a reference sine wave generator 60, a subtractor 61, a comparator 62, and a waveform shaping circuit 62a as shown in FIG. , Triangular wave generator 63, NOT circuit 64,
And a waveform shaping circuit 64a, and operates as shown in FIG. The reference sine wave generator 60 is connected to the input voltage detector 15 of FIG. 1 by a line 35, and is synchronized with the voltage of the power supply 1 and has the same frequency (50 Hz or 60H) as the power supply 1.
The reference sine wave voltage E20 of z) is generated as shown in FIG. One input terminal of the subtractor 61 is a reference sine wave generator 6.
0 and this other input terminal is connected by a line 34 to the output voltage detector 13 of FIG. As a result, the subtractor 61 outputs the reference sine wave voltage E20 and the output detection voltage E
An error voltage E22 with respect to 21 is generated. The comparator 62 connected to the subtractor 61 and the triangular wave generator 63 compares the error voltage E22 with the triangular wave voltage E23 as shown in FIG.
A binary output E24 consisting of a WM (pulse width modulation) waveform is generated. The triangular wave generator 63 generates a triangular wave voltage E23 at a repetition frequency (for example, 20 kHz) sufficiently higher than the frequency of the power supply 1. The output E24 of the comparator 62 is sent to the lines 30 and 33 via the waveform shaping circuit 62a, and is output to the first and fourth inverter switches S of the second converter 7.
1, used for control of S4. The NOT circuit 64 connected to the comparator 62 inverts the output E24 of the comparator 62 to generate an output E25 shown in FIG. NOT circuit 6
The output E25 of line 4 is applied to line 3 via the waveform shaping circuit 64a.
1, 32. The waveform shaping circuits 62a and 64 of FIG.
a has a function similar to those of the waveform shaping circuits 50a and 52a of FIG.
The pulse width of the output E25 of the T circuit 64 is slightly narrowed. The lines 30, 31, 32 and 33 in FIG. 6 are connected to the control terminals (bases) of the first to fourth inverter switches S1 to S4 of the second converter 7 in FIG. The first to fourth inverter switches S1 to S4 correspond to the two types of control signals E shown in FIG.
When the on / off control is performed based on E24 and E25, the DC voltage of the capacitor 9 and the storage battery 10 is converted into an AC voltage, and a voltage for adjusting the output voltage to the secondary winding N2 of the transformer Tr is obtained. The voltage obtained at the secondary winding N2 has a waveform synchronized with the voltage of the power supply 1. If the voltage waveform of the secondary winding N2 is in phase with the voltage waveform of the power supply 1,
The voltage waveform of the load 3 is obtained by adding the voltage waveform of the secondary winding N2 to the voltage waveform of the load 3. Conversely, when the voltage waveform of the secondary winding N2 has an opposite phase (180 ° phase difference) to the voltage waveform of the power supply 1, the voltage waveform of the secondary winding N2 is subtracted from the voltage waveform of the power supply 1. The waveform becomes the voltage waveform of the load 3. The amplitude and phase of the voltage waveform of the secondary winding N2 are controlled by inverter switches S1 to S4. As a result, load 3
Is controlled by the second converter 7 to be constant.

The power supply shown in FIGS. 1 to 9 has the following effects. (1) The capacitor 9 and the storage battery 10 function as a DC power supply for the second converter 7 when the power supply 1 is normal, and function as a DC power supply for the first converter 5 when the power supply 1 fails or the voltage drops. . That is, the capacitor 9 and the storage battery 10
Are used in both the first and second converters 5,7. Therefore, the power supply device can be reduced in cost and size. (2) Since the first converter 5 performs harmonic current compensation and reactive current compensation, harmonics based on the load 3 are connected to the AC power supply line closer to the power supply 1 than the connection points P1 and P2 of the first converter 5. The wave current component and the reactive current component do not substantially flow, and only the effective current of the fundamental wave flows. Therefore, the power supply terminals 2a, 2b
Thus, the harmonic current component and the reactive current component of the input current flowing through are reduced, and the waveform can be improved, the power factor can be improved, and the power loss can be reduced. (3) Since the output voltage is adjusted by the second converter 7, a stabilized voltage can be supplied to the load 3 both when the load 3 fluctuates and when the voltage of the power supply 1 fluctuates. . (4) Since the second converter 7 is configured to add or subtract the adjustment voltage to or from the voltage of the power supply 1, the power capacity of the second converter 7 is used to compensate for the fluctuation of the voltage of the load 3. It can be set to the required power capacity. In other words,
The power capacity of the second converter 7 can be smaller than the power capacity of the load 3. As a result, the size and the loss of the second converter 7 can be reduced. In this embodiment, the second
The secondary winding N2 of the converter 7 has a rated voltage of about 2
Only an AC voltage of 0% is applied. Therefore, the power loss here is 1/5 of the conventional method in which all of the rated voltages are added. (5) Reference sine wave generator 5 of inverter control circuit 37
3 generates a reference sine wave in synchronism with the voltage of the power supply 1 when the power supply 1 is normal, and generates a reference sine wave continuously before the power failure when the power supply 1 fails. Supply continuity can be maintained. But,
Power supply devices are required to be reduced in size and cost .

[0023]

[The first embodiment] Next, above with reference to FIGS. 10 to 14
A power supply according to one embodiment for meeting the demand will be described.
However, the basic configuration in FIGS. 15 to 22 for FIGS. 10 shows a first embodiment 14 and further illustrating the alternative embodiment
9 which are substantially the same as those shown in FIGS. 1 to 9 are denoted by the same reference numerals, and description thereof will be omitted.

The power supply apparatus of the first embodiment shown in FIG. 10,
First and second capacitors 9a, 9b and first converter 5
b and the basic configuration shown in FIG. 1 except for the first control circuit 6a.
And the same configuration as the power supply device. First and second
The series circuit of the capacitors 9a and 9b is parallel to the storage battery 101.
It is connected to the. The first converter 5b in FIG.
As shown in FIG. 1, the circuit is a half-bridge type circuit, including first and second switches Q1, Q2, first and second diodes D1, D2, a filter reactor L1, a filter capacitor C1, and a transformer. 70 . Since the first converter 5b is a half-bridge type conversion circuit, the series circuit of the first and second capacitors 9a and 9b is connected in parallel with the series circuit of the first and second switches Q1 and Q2 and the storage battery 10. It is connected to the. The interconnection point P3 of the first and second capacitors 9a, 9b is connected to the first output terminal 4a. First and second switches Q1
, Q2 are connected to a filter reactor L1.
, Filter capacitor C1 and winding 71 of transformer 70
Has a tap 72 and is divided into an upper half 71a and a lower half 71b.
Cracked. Tap 72 is connected to reactor L1 via reactor L1.
Connected to the interconnection point P4 of the first and second switches Q1, Q2.
Has been continued. One end 73 of the winding 71 is connected to the first output terminal 4
a and the first and second capacitors 9
a, 9b are connected to the interconnection point P3. Winding 71
Is connected to the second output terminal 4b and the second power supply terminal 2b.
It is connected to the. Filter capacitor C1 is a coil
81 is connected in parallel to the lower half 71b. The first and second diodes D1, D2 are connected in anti-parallel to the first and second switches Q1, Q2.

As shown in FIG. 12, the first control circuit 6a includes the third and fourth control signal lines 22 and 23 and the switches 39c, 39d, 40c and 40 of the first control circuit 6 shown in FIG.
d, lines 41c, 41d, 42c, and 42d are omitted. Further, the compensation current control circuit 36a shown in FIG.
Are the lines 41c and 41d from FIG. 4 as shown in FIG.
Is equivalent to omitting. Further, the inverter control circuit 37a of FIG.
This corresponds to the case where c and 42d are omitted. Therefore, the first and second switches Q1 and Q2 in FIG. 11 are alternately turned on and off in the compensation current supply mode based on the same control signals as the control signals E7 and E8 in FIG. Are turned on and off alternately based on the same control signal as the control signals E14 and E15.

[0026]

[Compensation Operation] The operation when the first converter 5b in FIG. 11 operates in the compensation mode will be described. 7 to t2 in FIG. 7 during a period in which a positive half-wave voltage is generated from the power supply 1.
During the period corresponding to the above, the first switch Q1 is turned off,
Switch Q2 is turned on. As a result, the power supply 1, the power switch 16, the secondary winding N2, the line 18, the second capacitor 9b, the second diode D2, the reactor L1,
A closed circuit of the lower half 71b of the coil 71 and the line 19 is formed , and a charging current for the second capacitor 9b flows.
In a period corresponding to t2 to t3 in FIG. 7, the first switch Q1 is turned on and the second switch Q2 is turned off, so that the power source 1, the power switch 16, the secondary winding N2, the line 18, A first capacitor 9a, a first switch Q1, a reactor L1, a filter capacitor C1, and a closed circuit of the line 19 are formed to remove harmonic current components and reactive current components of the current of the load 3, that is, to improve the waveform. And power
A compensation current for improving the efficiency flows. During a period corresponding to t4 to t5 in FIG. 7 during a negative half-wave of the voltage of the power supply 1, the first switch Q1 is turned off and the second switch Q2 is turned off.
Is turned on, and power supply 1, line 19, filter capacitor
The sensor C1, the reactor L1, the second switch Q2, the second
Of the capacitor 9b, the line 18, the secondary winding N2, and the power switch 16. The current flowing through the closed circuit removes harmonic current components and reactive current components of the current of the load 3, that is, functions as a compensation current for waveform improvement and power factor improvement . In the period corresponding to the period from t5 to t6 in FIG.
Switch Q1 is turned on, the second switch Q2 is turned off, and the power supply 1, the line 19, the lower half 71b of the coil 71,
Reactor L1, diode D1, first capacitor 9
a, line 18, secondary winding N2, and power switch 16
Is formed, and the charging current of the first capacitor 9a flows. Storage battery 10 includes first and second capacitors 9
The battery is charged by the sum of the voltages a and 9b. First of FIG.
And the second switches Q1 and Q2 are controlled in the same manner as the first and second switches Q1 and Q2 in FIG. 2, so that when the power is supplied from the power supply 1 to the load 3, the first converter 5a As a result, supply of a compensation current for waveform improvement and power factor improvement, and constant voltage charging of the capacitors 9a and 9b and the storage battery 10 can be achieved.

[0027]

[Inverter operation] When the power supply 1 is in a power failure state, the first converter 5b is controlled by signals similar to the control signals E14 and E15 in FIG. 8, and operates as a half-bridge type inverter.
The DC voltage of the storage battery 10 and the capacitors 9a and 9b is converted into an AC voltage and supplied to the load 3. That is, during the ON period of the first switch Q1, the first capacitor 9a, the first switch Q1, the filter reactor L1, the filter capacitor C1, the line 19, the load 3, and the line 18
Is formed, and during the ON period of the second switch Q2, the second capacitor 9b, the line 18, the load 3, and the line
19. A closed circuit of the filter capacitor C1, the filter reactor L1, and the second switch Q2 is formed. Since the on-time width of the first and second switches Q1 and Q2 changes according to the change in the amplitude of the error voltage E13 in FIG. 8, the voltage of the filter capacitor C1 becomes an approximate sine wave. Since the capacitor C1 is connected in parallel with the load 3, the load 3 is supplied with an approximate sinusoidal voltage.

The power supply shown in FIGS. 10 and 11 is the same as the power supply of the basic configuration of FIGS. 1 and 2 except that the first converter 5b is a half-bridge type converter . has the same effect as this. In addition, the first change
Since the exchanger 5b is a modified half-bridge circuit,
A reduction in size and cost can be achieved.

[0029]

Second Embodiment A power supply device according to a second embodiment shown in FIGS. 15 and 16 is different from the power supply device according to the second embodiment shown in FIGS. 1 and 2 in that the second converter 7 is a half-bridge type second converter. 7b, and the other parts are the same as those shown in FIGS. 1 and 2 . As shown in FIG. 16 , the second converter 7b of FIG. 15 includes first and second inverter switches S1 and S2, first and second inverter diodes D11 and D12, and first and second inverter switches D1 and D12. a capacitor C11, C12 for the inverter, the first
Auto-transformer T having a second filter reactor L2, a second filter capacitor C2, and a coil Ns.
r ' . The series circuit of the first and second inverter capacitors C11 and C12 is composed of a capacitor 9 and a storage battery 10.
Are connected in parallel. The coil Ns is connected via a second filter reactor L2 between the interconnection point of the first and second inverter switches S1 and S2 and the interconnection point of the first and second inverter capacitors C11 and C12.
It is connected to. A tap 80 is provided on the coil Ns.
The tap 80 is connected to the first through the power switch 16.
Are connected to the power supply terminal 2a. One end of the coil Ns 8
Reference numeral 1 denotes first and second inverter capacitors C11 and C12.
And the first output terminal 4
a. The other end 82 of the coil Ns is
Interconnection point of the two switches S1 and S2 via the switch L2
It is connected to the. The second filter capacitor C2 is
It is connected in parallel to the coil Ns .

The second control circuit 8a of the second embodiment, the line 32, 33 from the second control circuit 8 of the basic configuration of FIG. 6
Is equivalent to the one obtained by removing. Therefore, the first and second inverter switches S1 and S2 in FIG. 16 are ON / OFF controlled by signals corresponding to the control signals E24 and E25 in FIG.
While the first inverter switch S1 is on, the first inverter capacitor C11, the first inverter switch S1, the second filter reactor L2,
A current in the first direction flows through the closed circuit including the coil Ns . Also, during the ON period of the second inverter switch S2, the second inverter capacitor C12 and the coil N
s, a current in the second direction flows through a closed circuit including the second filter reactor L2 and the second inverter switch S2. Thereby, an AC voltage can be obtained in the coil Ns . The first and second inverter capacitors C11 and C12 are charged with the voltage of the capacitor 9 and the storage battery 10, and have a function of dividing these voltages by half. To adjust the voltage of load 3, tap 8 of coil Ns
A voltage between 0 and one end 81 is used.
1 is added to the voltage. Power unit of the second embodiment, since the second converter 7b are configured to the power supply substantially identical to the first embodiment except that it is a half bridge type, first embodiment It has the same effect as the example.

[0031]

Third Embodiment A power supply according to a third embodiment shown in FIG. 17 has a second converter 7 in which a part of the second converter 7 of the first embodiment is modified.
This is the same as the power supply device of the first embodiment except that the converter 7c is provided. The control circuit of the first converter 5 not shown in FIG. 17 has the same configuration as the first control circuit 6 of the basic configuration of FIG. Also, the second
The control circuit of the converter 7c is the control circuit 8a of the second embodiment.
It is configured identically. The second of the third embodiment of FIG. 17
Converter 7c corresponds to that omitting the coil Ns from FIG. That is, one end of the second filter capacitor C2 is connected to the first and second inverter capacitors C11 and C12.
And the first output terminal 4
a, and the other end of the capacitor C2 is connected to a first power supply terminal 2a via a power supply switch 16 and a first and second inverter switch S1,. It is connected to the interconnection point of S2.

[0032] Figure 1 two switches S1, S2 in FIG. 17
When the same circuit as the control circuit 8a of the second embodiment shown in FIG. 5 is used to alternately turn on and off, an AC voltage is obtained on the capacitor C2 by the operation of the well-known half-bridge type inverter. Since the capacitor C2 is connected in series between the power supply terminal 2a and the output terminal 4a, the capacitor C2
Is added to the voltage of the power supply 1. According to the third embodiment, the same effects as those of the first and second embodiments can be obtained.

[0033]

Fourth Embodiment A power supply device shown in FIG. 18 is a half-bridge type power supply device in which the first converter 5 of the second embodiment shown in FIG. 16 is modified.
A first converter 5a is provided, and first and second capacitors are provided.
It has the same configuration as in FIG. 16 except that a series circuit of the sensors C1 and C2 is provided in the same manner as in FIG. First converter 5a
Are the first and second switches Q1, Q2 and the first and second switches Q1, Q2.
Diodes D1, D2 and first filter reactor L
1 and a first filter capacitor C1. FIG.
8, the first and second switches Q1, Q2 and the first
And second diodes D1 and D2 and first and second capacitors.
The capacitors C1 and C2 are connected in the same manner as in FIG. H
The filter capacitor C1 is connected in parallel with the load 3.
You. The filter reactor L1 is connected to the switches Q1 and Q2.
Connected between the interconnection point P4 and the output terminal 4b.
You. The first and second switches Q1 and Q2 are connected to the first switch Q1 in FIG.
And is similarly controlled by the same circuit as the control circuit 6a. Figure 1
As shown in FIG. 8 , even when both the first and second converters 5a and 7b are configured as a half-bridge type, the same effects as those of the first to third embodiments can be obtained.

[0034]

Power supply of the fifth embodiment of the fifth embodiment Figure 19,
This corresponds to a configuration in which a second converter 7d having a configuration in which the capacitors C11 and C12 are removed from the second converter 7b of the fourth embodiment in FIG. 18 is provided. In FIG. 18 , two capacitors 9
a, 9b and two other capacitors C11, C12
Since the series circuits are connected in parallel with each other, FIG. 1 omitting the two capacitors C11, C12 of the second transducer 7b
Even with the circuit configuration of FIG. 9, the same operation as the circuit of FIG. 18 can be performed. The fifth embodiment is a very simple circuit and has a first to a fifth circuits.
The same effects as in the fourth embodiment can be obtained.

[0035]

Power apparatus according to the sixth embodiment of FIG. 20 [sixth embodiment of] is
Corresponds to a modification of the second transducer 7b of the fourth embodiment of FIG. 18. Second transducer 7e in FIG. 20 can the two capacitors C11, C12 saving from the second transducer 7b of Figure 18
And a transformer Tr having a leakage inductance . In FIG. 20 , two capacitors 9
a and 9b are connected to the second converter 7e as in FIG.
But it is used. The transformer Tr has the same shape as in FIG.
Has been established. The primary winding N1 of the transformer Tr is a switch
The interconnection point of S1 and S2 and the interconnection of capacitors C1 and C2
Connected between connection points. The secondary winding N2 is shown in FIG.
Are connected in the same way. Filter capacitor C2
It is connected in parallel to the secondary winding N2. According to the sixth embodiment, the same effects as those of the fourth and fifth embodiments can be obtained.

[0036]

Power unit of the seventh embodiment of the seventh embodiment] FIG. 21 is
This corresponds to a configuration in which the second converter 7b of the fourth embodiment in FIG. 18 is replaced with a second converter 7f. The second converter 7f in FIG. 21 corresponds to the second converter 7c in FIG. 17 from which the two capacitors C11 and C12 are omitted. In FIG. 21 , 2
One of the capacitor 9a, a series circuit of 9b is used instead of the two capacitors C11, a series circuit of C12 in FIG. 17. Therefore, one end of the capacitor C2 is connected to the reactor L2.
Through the first and second inverter switches S1, S2.
The other end of the capacitor C2 is connected to the interconnection point of the first and second capacitors 9a and 9b. According to the seventh embodiment, effects similar to those of the fourth embodiment can be obtained.

[0037]

Eighth Embodiment FIG. 22 shows a three-phase power supply according to an eighth embodiment. The power supply includes first, second, and third power supply terminals 2a, 2b, 2c connected to a three-phase AC power supply 1a;
Phase load 3a, output terminals 4a, 4b, 4c, three-phase first converter 5c, first control circuit 6b, three-phase second converter 7g, and second control Circuit 8b, capacitor 9, storage battery 10, and three load current detectors 11
a, 11b, 11c and three compensation current detectors 12a,
12b, 12c, a three-phase output voltage detector 13a, a DC voltage detector 14, a power supply voltage detector 15a, three-phase power switches 16a, 16b, 16c, and a power failure detection circuit 1.
7a.

The first converter 5c and the second converter 7g are obtained by modifying the single-phase circuit of the second embodiment shown in FIG. 15 into a three-phase circuit. Construct a three-phase circuit based on a single-phase circuit
Is well known, and a detailed description of the three-phase circuit will be omitted. Figure
22 except that the first control circuit 6b, the second control circuit 8b, the output voltage detector 13a, the power supply voltage detector 15a, and the power failure detection circuit 17a have a three-phase circuit configuration. Are substantially the same as those corresponding to.

According to the eighth embodiment, the same effect as that of the first embodiment can be obtained.

[0040]

[Modifications] The present invention is not limited to the above-described embodiment, and for example, the following modifications are possible. (1) second second transducer 7b, and 19 in FIG. 18
Instead of the converter 7d, a converter corresponding to the second converter 7c in FIG. 17 can be provided. In addition, FIG. 19, Fig. 2
0, the first 11 in place of the first transducer 5a of Figure 21
Converter 5b can be used. (2) The switches Q1 to Q6 and S1 to S6 can be semiconductor switches such as a field effect transistor (FET) and an insulated gate bipolar transistor (IGBT). (3) The diodes D1 to D6 and D11 to D16 can be built-in diodes of the switches Q1 to Q6 and S1 to S6. When the built-in diode is used as described above, the switches Q1 to Q6 and S1 to S6 are constituted by an insulated gate field effect transistor or an insulated gate bipolar transistor (IGBT), and a pn junction between the source and the drain is used as the diode. It is desirable to do. (4) The control format of the switches Q1 to Q4 of the first converter 5 and the control format of the switches S1 to S4 of the second converter 7 can be changed. For example, the first and second switches Q1, Q2 of the first converter 5 are turned on and off at a high repetition frequency of 20 kHz, and the third switch Q3 is turned on continuously during the positive half cycle of the AC voltage of the power supply 1. And the fourth switch Q4 can be turned on and off in the opposite manner to the third switch Q3.
Similarly to the switches Q3 and Q4, the third and fourth inverter switches S3 and S4 of the second converter 7 can be turned on and off corresponding to the positive half-wave and the negative half-wave of the AC voltage. . Also, in the three-phase converters 5c and 7e in FIG. 23, some switches can be turned on and off in synchronization with the AC voltage of the AC power supply 1a. (5) A part of the first control circuit 6 can be configured to be shared by the second control circuit 8. For example, the three triangular wave generators 51, 56, 63 may be reduced to two or one and shared, or the three reference sine wave generators 43, 5
3, 60 can be reduced to two or one and shared. (6) A part or all of the comparator 50, the NOT circuit 52, and the waveform shaping circuits 50a and 52a in FIG. (7) When the power outage period is short, the storage battery 10 can be omitted, and power can be supplied at the time of the power outage by the capacitor 9 or 9a, 9b.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a power supply device having a basic configuration.

FIG. 2 is a circuit diagram illustrating a main circuit portion including first and second converters of FIG. 1 in detail.

FIG. 3 is a block diagram showing a first control circuit of FIG. 1;

FIG. 4 is a circuit diagram illustrating a compensation current control circuit of FIG. 3 in detail.

FIG. 5 is a circuit diagram showing the inverter control circuit of FIG. 3 in detail.

FIG. 6 is a circuit diagram illustrating a second control circuit of FIG. 1 in detail.

FIG. 7 is a waveform chart showing the state of each part in FIG. 4 in principle.

FIG. 8 is a waveform diagram showing a state of each unit in FIG.

FIG. 9 is a waveform chart showing a state of each unit in FIG. 6;

FIG. 10 is a block diagram illustrating a power supply device according to the first embodiment.

FIG. 11 is a circuit diagram showing a main circuit portion including the first and second converters of FIG. 10 in detail.

FIG. 12 is a circuit diagram showing a first control circuit of FIG. 10;

FIG. 13 is a circuit diagram showing a compensation current control circuit of FIG.

FIG. 14 is a circuit diagram showing the inverter control circuit of FIG.

FIG. 15 is a block diagram illustrating a power supply device according to a second embodiment.

16 is a circuit diagram showing a main circuit part of the power supply unit of FIG.

FIG. 17 is a circuit diagram illustrating a main circuit portion of a power supply device according to a third embodiment.

FIG. 18 is a circuit diagram showing a main circuit portion of a power supply device according to a fourth embodiment in detail.

FIG. 19 is a circuit diagram showing a main circuit portion of a power supply device according to a fifth embodiment in detail.

FIG. 20 is a circuit diagram showing a main circuit portion of a power supply device according to a sixth embodiment in detail.

FIG. 21 is a circuit diagram showing a main circuit portion of a power supply device according to a seventh embodiment in detail.

FIG. 22 is a block diagram showing a three-phase power supply device according to an eighth embodiment.

[Description of Signs] 5, 5a, 5b First converter 6, 6a First control circuit 7, 7a, 7b, 7c, 7e Second converter 8, 8a Second control circuit 9, 9a, 9b Capacitor 10 Storage battery

Continuation of the front page (56) References JP-A-11-178216 (JP, A) JP-A-5-73160 (JP, A) JP-A-4-42740 (JP, A) JP-A-9-266631 (JP) , A) JP-A-5-260685 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02J 9/00-11/00

Claims (11)

(57) [Claims] To 1. A load and AC power supply terminals for supplying AC power, a series circuit of first and second capacitors, connected between said series circuit of said first and second capacitive load A first operation of generating a compensation current for reducing harmonic components and improving a power factor, and charging the first and second capacitors, and the first and second operations. a first converter configured to selectively perform a second operation of converting a DC voltage of a capacitor into an AC voltage; and an AC voltage from the AC power supply terminal to the load. When supplied, the first converter is controlled so that the first operation occurs. When the AC voltage is not supplied from the AC power supply terminal to the load, the second operation occurs. A first control circuit for controlling the first converter; The first and second capacitors are connected to a series circuit and are also connected between the AC power supply terminal and the load to adjust the DC voltage of the first and second capacitors to the voltage of the load. Uninterruptible power supply, comprising: a second converter configured to convert the AC voltage into a second voltage; and a second control circuit that controls the second converter so that the voltage of the load becomes a desired value. in the apparatus
There, the first transducer, parallel to the series circuit of the first and second capacitors
And a series circuit of first and second switches connected to the first and second switches, and connected in reverse parallel to the first and second switches.
A first filter reactor, a first filter capacitor, and a coil having a tap , wherein the coil is connected in parallel to the load;
Tap of the il via the first filter reactor
Connected to the interconnection point of the first and second switches.
And one end of the coil is connected to the first and second capacitors.
And the first filter capacitor is connected to the
The sensor is connected between the coil tap and the other end.
Uninterruptible power supply, characterized in that that. 2. The method according to claim 1, further comprising the steps of:
The uninterruptible power supply according to claim 1, further comprising a storage battery connected in parallel to the series circuit . 3. An AC for supplying AC power to a load.
A power supply terminal, a series circuit of first and second capacitors, a series circuit of the first and second capacitors, and the load;
To reduce harmonic components and improve power factor.
And the first and second
A first operation for charging a capacitor and the first and second
Second operation for converting DC voltage of capacitor to AC voltage
The first is configured to be able to take alternatively
A converter, and an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
If, 且connected in series circuit of said first and second capacitors
Connected between the AC power supply terminal and the load,
The DC voltage of the first and second capacitors is connected to the voltage of the load.
Is configured to convert to an AC voltage to regulate the pressure
And a second converter for setting the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There, the first transducer, parallel to the series circuit of the first and second capacitors
And a series circuit of first and second switches connected to the first and second switches, and connected in reverse parallel to the first and second switches.
A first filter reactor, a first filter capacitor, and a coil having a tap, wherein the coil is connected in parallel to the load;
Tap of the il via the first filter reactor
Connected to the interconnection point of the first and second switches.
And one end of the coil is connected to the first and second capacitors.
And the first filter capacitor is connected to the
The sensor is connected between the coil tap and the other end.
And the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
The second filter connected via the second filter reactor
A filter capacitor and a capacitor connected in parallel with the second filter capacitor.
And a transformer having a coil.
The tap is connected to the power terminal, and the coil is
One end of the coil is connected to the load, and the other end of the coil is
The first and second filters are connected via the second filter reactor.
Connected to the interconnection point of the two inverter switches.
Uninterruptible power supply, wherein the Turkey. 4. An AC power supply for supplying AC power to a load.
A source terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
And wherein the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
A primary winding of a transformer connected to the primary winding and electromagnetically coupled to and connected to the AC power supply terminal;
And a second winding connected in parallel with the primary winding or the secondary winding.
Uninterruptible power supply, characterized in that it consists of a capacitor of the filter. 5. A load and AC power supply terminals for supplying AC power, a series circuit of first and second capacitors, connected between said series circuit of said first and second capacitive load A first operation of generating a compensation current for reducing harmonic components and improving a power factor, and charging the first and second capacitors, and the first and second operations. a first converter configured to selectively perform a second operation of converting a DC voltage of a capacitor into an AC voltage; and an AC voltage from the AC power supply terminal to the load. When supplied, the first converter is controlled so that the first operation occurs. When the AC voltage is not supplied from the AC power supply terminal to the load, the second operation occurs. A first control circuit for controlling the first converter; The first and second capacitors are connected to a series circuit and are also connected between the AC power supply terminal and the load to adjust the DC voltage of the first and second capacitors to the voltage of the load. Uninterruptible power supply, comprising: a second converter configured to convert the AC voltage into a second voltage; and a second control circuit that controls the second converter so that the voltage of the load becomes a desired value. in the apparatus
There, the first transducer, parallel to the series circuit of the first and second capacitors
And a series circuit of first and second switches connected to the first and second switches, and connected in reverse parallel to the first and second switches.
A first filter reactor, a first filter capacitor, and a coil having a tap, wherein the coil is connected in parallel to the load;
Tap of the il via the first filter reactor
Connected to the interconnection point of the first and second switches.
And one end of the coil is connected to the first and second capacitors.
And the first filter capacitor is connected to the
The sensor is connected between the coil tap and the other end.
And the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
The second filter connected via the second filter reactor
And a filter capacitor for the second filter.
One end of the capacitor is connected to the power terminal, and the second terminal is connected to the second terminal.
The other end of the filter capacitor is connected to the load . 6. An AC power supply for supplying AC power to a load.
A source terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There are, said second transducer, the first and second in-connected in parallel with said capacitor
Series circuit of a capacitor for the inverter, and series circuit of the first and second capacitors for the inverter
The first and second inverter switches connected in parallel to
And a connection point between the first and second inverter switches.
Between the first and second inverter capacitors.
Connected to the connection point via a second filter reactor
And a capacitor connected in parallel to the second filter capacitor.
And a transformer having a coil.
The tap is connected to the power terminal, and the coil is
One end of the coil is connected to the load, and the other end of the coil is
The first and second filters are connected via the second filter reactor.
Connected to the interconnection point of the two inverter switches.
Uninterruptible power supply, wherein the Turkey. 7. An AC power supply for supplying AC power to a load.
A source terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There are, said second transducer, the first and second in-connected in parallel with said capacitor
Series circuit of a capacitor for the inverter, and series circuit of the first and second capacitors for the inverter
The first and second inverter switches connected in parallel to
And a connection point between the first and second inverter switches.
Between the first and second inverter capacitors.
Connected to the connection point via a second filter reactor
And a second filter capacitor,
One end of the filter capacitor is connected to the power supply terminal.
Is, the other end of the pre-Symbol second capacitor filters the load
The uninterruptible power supply according to claim, wherein the uninterruptible power supply is connected to a power supply. 8. An AC power supply for supplying AC power to a load.
A source terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There are, the capacitor series circuit of the first and second capacitors
, And the said first transducer is connected in parallel with the series circuit of the first and second capacitors
Connected in series with the first and second switches, and connected in reverse parallel to the first and second switches.
A first and second diode, an interconnection point of the first and second switches, and the first and second switches;
For the first filter between the interconnection point of the two capacitors
A first filter condenser connected via a reactor;
And the first filter capacitor is
The second converter is connected in parallel to a load, and the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
The second filter connected via the second filter reactor
A filter capacitor and a capacitor connected in parallel with the second filter capacitor.
And a transformer having a coil.
The tap is connected to the power terminal, and the coil is
One end of the coil is connected to the load, and the other end of the coil is
The first and second filters are connected via the second filter reactor.
Connected to the interconnection point of the two inverter switches.
Uninterruptible power supply apparatus according to claim Rukoto. 9. An AC power supply for supplying AC power to a load.
A source terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There are, the capacitor series circuit of the first and second capacitors
, And the said first transducer is connected in parallel with the series circuit of the first and second capacitors
Connected in series with the first and second switches, and connected in reverse parallel to the first and second switches.
A first and second diode, an interconnection point of the first and second switches, and the first and second switches;
For the first filter between the interconnection point of the two capacitors
A first filter condenser connected via a reactor;
And the first filter capacitor is
The second converter is connected in parallel to a load, and the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
A primary winding of a transformer connected to the primary winding and electromagnetically coupled to and connected to the AC power supply terminal;
And a second winding connected in parallel with the primary winding or the secondary winding.
And an uninterruptible power supply device comprising: 10. An AC for supplying AC power to a load.
A power supply terminal, a capacitor, and a harmonic component connected between the capacitor and the load.
To generate a compensation current to reduce the minute and improve the power factor.
And a first operation of charging the capacitor and the capacitor.
A second operation for converting the DC voltage of the capacitor to an AC voltage;
A first variant that can be taken as an alternative
And an AC voltage is supplied to the load from the AC power supply terminal.
The first operation so that the first operation occurs.
Control the converter and connect the AC to the load from the AC power supply terminal.
When no voltage is supplied, the second operation occurs.
Control circuit for controlling the first converter in such a manner
And the AC power supply terminal connected to the capacitor and
Also connected between the load and the DC voltage of the capacitor
The voltage of the load is converted to an AC voltage for adjustment.
And a second converter configured to adjust the voltage of the load to a desired value.
Uninterruptible power supply with a second control circuit for controlling
There are, the capacitor series circuit of the first and second capacitors
, And the said first transducer is connected in parallel with the series circuit of the first and second capacitors
Connected in series with the first and second switches, and connected in reverse parallel to the first and second switches.
A first and second diode, an interconnection point of the first and second switches, and the first and second switches;
For the first filter between the interconnection point of the two capacitors
A first filter condenser connected via a reactor;
And the first filter capacitor is
The second converter is connected in parallel to a load, and the second converter is connected in parallel to a series circuit of the first and second capacitors.
Series circuit of first and second inverter switches
And an interconnection point between the first and second inverter switches
And the interconnection point of the first and second capacitors
The second filter connected via the second filter reactor
And a filter capacitor for the second filter.
One end of the capacitor is connected to the power terminal, and the second terminal is connected to the second terminal.
The other end of the filter capacitor is connected to the load.
Uninterruptible power supply, characterized in that there. 11. The power supply is a three-phase AC power supply, the load is a three-phase load, the first converter is a three-phase converter, and the second converter is a three-phase converter. The uninterruptible power supply according to any one of claims 1 to 10, wherein the power supply is a power supply.