JP2001306159A - Power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system which can extend the maximum value of current which is able to supply without any changes in the structure of the transmission route which supplies power. SOLUTION: A commercial power source current monitoring unit 1 supplies information of the volume of current which flows from a commercial power supply ACV to load Z to a uninterruptible power supply 2. The uninterruptible power supply 2 supplies almost the same phase of current as the one, which the commercial power supply supplies to the load Z when a value of the information exceeds the threshold. When the current which flows on the load Z is less than the threshold, the uninterruptible power supply 2 sends almost the opposite phase of the current which was supplied by the commercial power supply as long as reverse tidal current never occurs, if the secondary battery of the uninterruptible power supply 2 is fully charged due to the current supplied by a recharging unit 3 to the commercial power supply ACV. When the commercial power supply ACV is stopped, the commercial power source current monitoring unit 1 shuts down the current route between the commercial power supply ACV and supplies power to the load Z.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a power supply system,
In particular, the present invention relates to a power supply system for preventing power supply abnormality and supplying power stably.

[0002]

2. Description of the Related Art Generally, electric power generated by a commercial AC power supply is supplied to electric equipment via a breaker. When the magnitude of the current passing through the current path provided by the breaker exceeds a threshold value, the breaker cuts off the current path to prevent power from being supplied from the AC power supply to the electric device, thereby preventing an excessive current from flowing. Prevent supply.

[0003]

However, the electric current flowing through the electric equipment is usually not constant even during the normal operation of the electric equipment. For this reason, when the breaker interrupts the current path every time the flowing current temporarily increases and exceeds the above-described threshold value, the normal operation of the electric device is hindered.

On the other hand, if the above-mentioned threshold value is set to a value exceeding the maximum value of the current flowing during normal operation of the electric equipment, the breaker will operate during the normal operation of the electric equipment. Blocking the road is prevented. However, in this case, the structure of the current path of the breaker needs to be a structure that can afford the maximum current that can flow to the electric equipment, and the breaker needs to be remodeled or replaced, and the path for supplying power is required. Maintenance becomes complicated.

The present invention has been made in view of the above circumstances, and provides a power supply system capable of increasing the maximum value of a current that can be supplied without changing the structure of a transmission line for supplying power. The purpose is to:

[0006]

In order to achieve the above object, a power supply system according to the present invention comprises an external power source for supplying AC power and a power supply for transmitting power supplied from an external power source. A current monitoring unit that detects the magnitude of the current supplied to the load and outputs current information indicating the magnitude of the detected current, and acquires the current information output by the current monitoring unit, and acquires the acquired current information It is determined whether or not the magnitude of the current indicated exceeds a predetermined reserve power supply start value, and when it is determined that the current power exceeds the predetermined reserve power supply start value, a supplementary power supply for supplying power to the load is provided. Features.

According to such a power supply system, when the current supplied by the power source exceeds the reserve power supply start value, the supplementary power supply supplies power to the load. Therefore, the maximum value of the current that can be supplied to the load increases without changing the structure of the transmission line.

The replenishing power source generates power, and when the power generation means determines that the magnitude of the current indicated by the current information acquired by itself is equal to or smaller than the preliminary power supply start value, the power source generates power. Reverse power transmission means for supplying power to the power source. Thus, when the power supplied to the load is equal to or less than the reserve power supply start value, the power generated by the power generation unit is transmitted to the power source in reverse, and the power is effectively used.

The reverse power transmitting means converts the power stored by the power generating means, and has a phase substantially opposite to the phase of the current indicated by the current information, and the effective value of the current indicated by the current information is substantially changed. If a current having an amplitude such that it becomes 0 is generated and the generated current is supplied to the power source,
Of the power transmitted from the reverse power transmission means to the power source, the amount of reactive power is substantially minimized, and efficient power transmission is performed.

The power generating means may include, for example, charging means for storing power generated by the power generating means, and the reverse power transmitting means may supply the power stored by the charging means to the power source. In this case, the replenishment power source includes a full charge determination unit that determines whether the charging unit is substantially in a fully charged state, and the charging unit determines whether the magnitude of the current indicated by the current information is equal to the current value. When the supplementary power supply determines that the value does not exceed the reserve power supply start value, and when the full charge determination unit determines that the charging unit is not substantially in the fully charged state, it generates power. The power is stored, and the reverse power transmission unit determines that the supplementary power supply determines that the magnitude of the current indicated by the current information does not exceed the preliminary power supply start value, and that the full charge determination unit includes When it is determined that the charging unit is substantially in a fully charged state, the power stored by the charging unit may be supplied to the power source. Thereby, the power transmitted to the power source is transmitted after the power to be supplied to the load is sufficiently accumulated. Therefore, the balance between the stable supply of power to the load and the effective use of power by transmitting power to the power source is achieved.

The current monitoring unit determines whether or not the polarity of the voltage at the other point with respect to one of the two predetermined points on the transmission path is the same for a predetermined time or more. Determining means for supplying power failure information indicating the power supply to the supplementary power supply, and when the determining means determines that the polarity of the voltage at the predetermined position is the same polarity for the predetermined time or more, the transmission line is substantially cut off The first power supply means for supplying power to the load when the power supply information output by the current monitoring unit is supplied. Then, power is supplied from the power supply for replenishment.

The current monitoring section determines whether or not the magnitude of the current detected by the current monitoring section exceeds a predetermined maximum current value that is larger than the preliminary power supply start value. The provision of the second blocking means for substantially blocking the road prevents the supply of an excessive current from the power source.

[0013] The current monitoring unit, based on the direction of the current detected by the self and the direction of the electromotive force generated by the external power source, from the supplementary power supply to the external power source, It is determined whether or not a current is flowing in a direction for canceling the electromotive force, and if it is determined that the current is flowing, a third shut-off means for substantially shutting off the transmission line is provided. Danger due to inflow of power flow to the source (reverse power flow) is prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A power supply system according to an embodiment of the present invention will be described below by taking a power supply system for supplying electric power supplied from a single-phase AC commercial power supply to an external device as an example.

FIG. 1 shows a physical configuration of a power supply system according to an embodiment of the present invention. As shown, the power supply system includes a commercial power supply current monitoring unit 1, an uninterruptible power supply 2, and a power generation unit 3.

The commercial power supply current monitoring unit 1 includes, for example, a relay, a current transformer, an amplifier, and a comparator, and has an input terminal, an output terminal, and a synchronous output terminal. The input terminal of the commercial power supply current monitoring unit 1 is connected to one pole of an external commercial power supply ACV that supplies a single-phase AC current, and the output terminal is one of input / output terminals of the uninterruptible power supply 2 which will be described later. Connected to poles. The synchronous output terminal of the commercial power supply current monitoring unit 1 is connected to a synchronous input terminal of the uninterruptible power supply 2 described later.

The relay of the commercial power supply current monitoring unit 1 has a contact and a drive unit, and turns off the contact when a signal for instructing the drive unit to turn off the contact is supplied to the drive unit. When this signal is not supplied, the contact is turned on.

The current transformer of the commercial power supply current monitoring section 1 has a primary winding and a secondary winding, and both ends of the secondary winding are connected to an amplifier. The primary winding is cascaded with the contacts of the relay of the commercial power supply current monitoring unit 1 to form a series circuit. One end and the other end of this series circuit are connected to the input terminal and the output of the commercial power supply current monitoring unit 1. Make an end.

The amplifier of the commercial power supply current monitoring unit 1 is connected to at least one end of the secondary winding of the current transformer.
A signal representing the instantaneous value of the current flowing through the primary winding of the current transformer is generated and output to the synchronous output terminal of the commercial power supply current monitoring unit 1, and this signal is also supplied to the comparator.

The comparator of the commercial power supply current monitoring unit 1 determines whether or not the instantaneous value of the current indicated by the signal supplied from the amplifier is equal to or greater than a predetermined maximum power receiving current value, and is equal to or greater than the maximum power receiving current value. , A signal to turn off the contact of the relay is supplied to the drive unit of the relay. Further, the comparator determines whether or not the voltage of the commercial power supply current monitoring unit 1 satisfies a condition to be described later. If it determines that the voltage is satisfied, the comparator supplies a signal to turn off the contact of the relay to the driving unit of the relay, and A power failure signal described later is output to a synchronous output terminal of the power supply current monitoring unit 1.

The uninterruptible power supply 2 includes a charging unit and a DC / AC converter, and has an input / output terminal, a synchronous input terminal, and a charging input terminal. The input / output terminal of the uninterruptible power supply 2 has a pair of poles, and both poles of the input / output terminal are connected one-to-one to both ends of an external load Z to which power is supplied.
One pole of the input / output terminal is connected to the output terminal of the commercial power supply current monitoring unit 1, and the other pole is connected to the commercial power supply ACV.
Are connected to the other pole that is not connected to the input terminal of the commercial power supply current monitoring unit 1. The synchronous input terminal of the uninterruptible power supply 2 is connected to the commercial power supply current monitoring unit 1.
The charging input terminal of the uninterruptible power supply 2 includes a positive electrode and a negative electrode, and the positive electrode and the negative electrode of the charging input terminal of the uninterruptible power supply 2 and the output terminal of the power generation unit 3 are connected to each other.

The DC-AC converter of the uninterruptible power supply 2 performs a non-interruptible power supply operation on the basis of a signal supplied to a synchronous input terminal of the uninterruptible power supply 2 and a voltage between both ends of a rechargeable battery included in the charging unit, which will be described later. It is determined whether or not DC power supplied by the charging unit of the power failure power supply 2 is to be converted into AC power. When it is determined that the conversion is performed, the conversion is performed as described below, and the AC power obtained as a result of the conversion is supplied from the input / output terminal of the uninterruptible power supply 2 as described below. If it is determined that the conversion is not to be performed, the current path between the input / output terminal of the uninterruptible power supply 2 and itself is substantially cut off. In addition, the DC-AC converter substantially cuts off the current path between the input / output terminal and itself even when the instantaneous value of the current supplied from the input / output terminal exceeds a predetermined rated current value. I do. The determination as to whether or not the instantaneous value of the current supplied from the input / output terminal exceeds the rated current value may be made, for example, by detecting the magnitude of the current flowing from the charging unit and based on the detection result.

The charging section of the uninterruptible power supply 2 is composed of a secondary battery and a switching circuit. The switching circuit is connected to the uninterruptible power supply 2 based on a signal supplied to a synchronous input terminal of the uninterruptible power supply 2. Connects and disconnects the charging input terminal from its own secondary battery. Then, when the charging input terminal and the secondary battery are connected to each other, the secondary battery charges DC power supplied to itself from the charging input terminal. On the other hand, when the charging input terminal and the secondary battery are cut off from each other, the secondary battery supplies DC power to the DC-AC converter of the uninterruptible power supply 2. When the secondary battery of the charging unit is substantially fully charged (that is, when the amount of charge stored in the secondary battery has reached a substantially storable maximum amount), both ends of the secondary battery are charged. It has the property that the voltage between them becomes a voltage in a predetermined range.

The power generation section 3 is composed of a solar cell or the like, and has an output terminal composed of a positive electrode and a negative electrode. The positive terminal of the output terminal of the power generation unit 3 is connected to the positive terminal of the charging input terminal of the uninterruptible power supply 2, and the negative terminal of the output terminal is connected to the negative terminal of the charging input terminal of the uninterruptible power supply 2. The power generation unit 3 supplies the power generated by the power generation unit 3 including the DC component to the uninterruptible power supply 2 such that the positive electrode at its output terminal has a higher potential than the negative electrode.

When a single-phase AC voltage is supplied between the poles of the commercial power supply ACV, a current flows from the commercial power supply ACV to the load Z via the input terminal and the output terminal of the commercial power supply current monitoring unit 1. The commercial power supply current monitoring unit 1 generates a signal indicating the instantaneous value of the current flowing between its own input terminal and its own output terminal, and transfers the generated signal from its own synchronous output terminal to the synchronous input terminal of the uninterruptible power supply 2. Supply.

On the other hand, the power generation unit 3 generates a voltage including a DC component, and applies the generated voltage between both electrodes of its own output terminal to both electrodes of a charging input terminal of the uninterruptible power supply 2. However,
The power generation unit 3 applies a voltage such that the positive electrode of the charging input terminal has a positive polarity with respect to the negative electrode of the charging input terminal.

The uninterruptible power supply 2 repeatedly determines whether or not the instantaneous value of the current indicated by the signal supplied to its own synchronous input terminal exceeds a predetermined threshold value smaller than the above-mentioned maximum receiving current value. . When it is determined that the secondary battery is not exceeded, each time it is determined whether or not the secondary battery is substantially fully charged based on the voltage between both ends of the secondary battery. (That is, the voltage between both ends of the secondary battery is
It is determined whether or not the secondary battery is substantially in a fully charged state. )

When it is determined that the battery is fully charged,
The DC power generated by the secondary battery is subjected to DC-AC conversion, so that an AC current (that is, a commercial power supply) having a substantially opposite phase to the phase of the current represented by the signal supplied to its own synchronous input terminal is obtained. An AC current having a phase substantially opposite to that of the AC current supplied by the ACV is generated. Then, this alternating current is supplied from its own input / output terminal to the commercial power supply ACV.

The uninterruptible power supply 2 converts AC current to commercial power AC
When the AC power is supplied to V, the effective value of the current indicated by the signal supplied from the commercial power supply current monitoring unit 1 becomes substantially 0, which is the AC voltage generated between the two electrodes at its own input / output terminal in order to supply the AC current. Adjust as follows. Specifically, for example, when the uninterruptible power supply 2 supplies the alternating current to the commercial power supply ACV,
The effective value of the current indicated by the signal supplied from the commercial power supply current monitoring unit 1 is increased while increasing the effective value of the AC voltage generated between the poles of its own input / output terminal to supply the AC current over time. Determine repeatedly. Then, when it is determined that the effective value of the current indicated by the signal supplied from the commercial power supply current monitoring unit 1 has become substantially 0, the rise of the effective value of the voltage between the electrodes at its own input / output terminal is stopped, and Maintain the effective value of the voltage.

When the effective value of the current passing between the input terminal and the output terminal of the commercial power supply current monitoring unit 1 becomes substantially 0, the power flow flowing from the commercial power supply ACV to the load Z and the uninterruptible power supply 2 and the electric power flow flowing into the commercial power supply ACV is in a state of being offset by an almost equal amount. Therefore, when the power supplied from the uninterruptible power supply 2 to the commercial power supply ACV becomes substantially zero when the effective value of the current passing between the input terminal and the output terminal of the commercial power supply current monitoring unit 1 becomes zero, The size of the power flow flowing into the commercial power supply ACV from the
The power flow flowing from the AC power supply to the commercial power supply ACV has a maximum magnitude that does not exceed the power flow flowing from the commercial power supply ACV to the load Z (that is, a state in which reverse power flow occurs).

On the other hand, the uninterruptible power supply 2 has an instantaneous value of a current indicated by a signal supplied to its own synchronous input terminal that does not exceed the first threshold value, and its own secondary battery is substantially When it is determined that the battery is not fully charged, the voltage applied to its own charging input terminal is applied to its own secondary battery. As a result, the power generated by the power generation unit 3 is supplied to the secondary battery of the uninterruptible power supply 2, and the secondary battery is charged.

When the uninterruptible power supply 2 determines that the instantaneous value of the current indicated by the signal supplied to its own synchronous input terminal exceeds the above-described threshold value, the uninterruptible power supply 2 Is converted from DC to AC to generate an AC current substantially in phase with the phase of the current represented by the signal supplied to its own synchronization input terminal. Then, this alternating current is supplied from its own input / output terminal to the load Z. The instantaneous value of the alternating current supplied from the uninterruptible power supply 2 to the load Z corresponds to, for example, a difference between an instantaneous value represented by a signal supplied to a synchronous input terminal of the uninterruptible power supply 2 and a predetermined maximum value. Any size is acceptable.

The commercial power supply current monitoring section 1 also has the following features: (1) Of the two poles of the commercial power supply, one of the poles applied to its own input terminal maintains a voltage of the same polarity as the potential of the other pole. Whether or not a state (power failure state) in which the period lasts for more than a half cycle of the alternating current flowing from the commercial power supply ACV has occurred, and (2) the current flowing between its own input terminal and output terminal It is repeatedly determined whether or not the instantaneous value has exceeded the above-described maximum receiving current value. Then, when it is determined that the power failure state has not occurred and the instantaneous value of the current between the input terminal and the output terminal has not exceeded the maximum received current value, the connection between the own input terminal and the output terminal has been made. Keep in state.

On the other hand, when it is determined that a power failure state has occurred, or when it is determined that the instantaneous value of the current between the input terminal and the output terminal has exceeded the maximum received current value, the connection between the own input terminal and the output terminal is determined. Substantially cut off. If it is determined that a power failure state has occurred, the synchronization input terminal of the uninterruptible power supply 2
A power failure signal indicating that the commercial power supply ACV has failed is supplied.

When the uninterruptible power supply 2 is supplied with the power outage signal, the uninterruptible power supply 2 converts the DC voltage generated by the secondary battery provided therein into a DC-
AC conversion, generates an AC current having substantially the same phase as the phase of the current represented by the signal supplied to its own synchronous input terminal until immediately before the power failure signal is supplied, and converts this AC current to its own input / output terminal. To the load Z. Note that the amplitude of the alternating current supplied to the load Z by the uninterruptible power supply 2 to which the power failure signal is supplied is substantially the same as the amplitude of the alternating current to be supplied by the commercial power supply ACV that is not in a power failure state.

When the instantaneous value of the current supplied from the input / output terminal exceeds the above-mentioned rated current value, the uninterruptible power supply 2 substantially provides a current path between the input / output terminal and the self. To stop the current supply.

The configuration of the power supply system is not limited to the above. For example, the commercial power supply current monitoring unit 1
A signal indicating the effective value of the current flowing between the own input terminal and the output terminal and a signal indicating the phase may be generated and supplied to the uninterruptible power supply 2. In this case, the uninterruptible power supply 2 replaces the operation of determining whether or not the instantaneous value of the current indicated by the signal supplied to its own synchronous input terminal exceeds a threshold value with the signal supplied to the synchronous input terminal. The operation for determining whether or not the effective value of the current indicated by exceeds the threshold value may be performed.

The uninterruptible power supply 2 may supply AC power having a different phase from the current represented by the signal supplied to its own synchronous input terminal from its own input / output terminal.

The commercial power supply current monitor 1 may have, for example, the configuration shown in FIG. That is, for example, the commercial power supply current monitoring unit 1 is provided with the above-mentioned relay contact
A relay drive section (hereinafter, referred to as a relay drive section Sb) and a current transformer (hereinafter, referred to as a relay drive section Sb).
Current transformer T) and diodes D1 to D4
, Zener diodes Dz1 to Dz4, and resistor R1
R3 and the capacitor C.

The diodes D1 to D4 are connected so as to form a bridge rectifier circuit. Specifically, the cathodes of the diodes D1 and D2 are connected to each other, the anodes of the diodes D3 and D4 are connected to each other,
The anode of the diode D1 and the cathode of the diode D3 are connected to each other, and the anode of the diode D2 and the cathode of the diode D4 are connected to each other.

The Zener diodes Dz1 and Dz2 are
They are connected in reverse series to each other to form a series circuit. The series circuit formed by the Zener diodes Dz1 and Dz2 is connected between the anode of the diode D1 and one of the two poles of the commercial power supply ACV that is not connected to the input terminal of the commercial power supply current monitoring unit 1. . Zener diodes Dz3 and Dz4 are also connected in anti-series to each other to form a series circuit. Zener diodes Dz3 and Dz
The series circuit formed by z4 includes the anode of the diode D2 and the commercial power supply current monitor 1
Connected to the other pole not connected to the input terminal. The Zener voltages of the Zener diodes Dz1 to Dz4 are substantially equal to each other, and the forward voltages of the Zener diodes Dz1 to Dz4 are also substantially equal to each other.

One end of the primary winding of the current transformer T is connected to the output end of the commercial power supply current monitoring unit 1, and the other end is
It is connected to one end of the relay contact Sa. One end of the secondary winding of the current transformer T is connected to one of the two poles of the commercial power supply ACV that is not connected to the input end of the commercial power supply current monitoring unit 1, and the other end is connected to the resistor R3. Connected to one end. However, assuming that an AC voltage is applied between both ends of the primary winding, a voltage having the same polarity as the above-mentioned one end of the primary winding is generated at the above-mentioned one end of the secondary winding.

The resistor R1 is connected between one of the two poles of the commercial power supply ACV that is not connected to the input terminal of the commercial power supply current monitor 1, and one end of the resistor R2. The other end of the resistor R2 is connected to the anode of the diode D1. The other end of the resistor R3 is connected to the anode of the diode D2.

The relay contact Sa has a pair of ends, and the relay drive section Sb has input terminals IN + and IN-. When a current flows from the input terminal IN + of the relay drive unit Sb to the input terminal IN−, both ends of the relay contact Sa are connected, and when no current flows between both input terminals of the relay drive unit Sb,
Both ends of the relay contact Sa are cut off. Relay contact Sa
Is connected to the above-mentioned other end of the current transformer T as described above, and the other end of the relay contact Sa is connected to the input end of the commercial power supply current monitoring unit 1. The input terminal IN + of the relay driving section Sb is connected to the cathode of the diode D1, and the input terminal IN + is connected to the anode of the diode D3.

The capacitor C is connected between the connection point of the resistors R1 and R2 and the above-mentioned one end of the relay contact Sa.

When the commercial power supply current monitoring section 1 has the configuration shown in FIG. 2, when a single-phase AC voltage is supplied between the two poles of the commercial power supply ACV, an AC voltage drop occurs across the resistor R1. appear. As a result, a current also flows through a series circuit formed by the resistor R2 and the three zener diodes Dz1 and Dz2, and a Zener diode Dz is connected between both ends of the series circuit formed by the zener diodes Dz1 and Dz2.
A voltage corresponding to the sum of the zener voltage 1 (or Dz2) and the forward voltage of the zener diode Dz2 (or Dz1) is generated.

Further, as a result of the current flowing from the commercial power supply ACV to the load Z via the input terminal and the output terminal of the commercial power supply current monitoring unit 1, an electromotive force is generated between both ends of the secondary winding of the current transformer T. Induced. As a result, a current also flows through a series circuit formed by the resistor R3 and the three zener diodes Dz3 and Dz4, and a Zener diode Dz is connected between both ends of the series circuit formed by the zener diodes Dz3 and Dz4.
3 (or Dz4) and a voltage corresponding to the sum of the forward voltage of the Zener diode Dz4 (or Dz3).

The absolute value of the voltage between both ends of the series circuit formed by the Zener diodes Dz1 and Dz2 and the absolute value of the voltage between both ends of the series circuit formed by the Zener diodes Dz3 and Dz4 are substantially equal to each other. Become equal. When no reverse power flow occurs, the polarity of the voltage at the connection point between the resistor R1 and the capacitor C and the polarity of the voltage at the connection point between the resistor R3 and the secondary winding of the current transformer T are:
When the potentials of the two poles of the commercial power supply ACV that are not connected to the input terminal of the commercial power supply current monitoring unit 1 are viewed as a reference, the polarities are opposite to each other. Therefore, the voltage of the anode of the diode D1 and the voltage of the anode of the diode D2 correspond to the commercial power supply current monitor 1
When the potentials of the poles that are not connected to the input terminal of are viewed as a reference, the polarities are opposite to each other. Therefore, a current flows through a path including the diode D1, the relay driving unit Sb, and the diode D4, or a path including the diode D2, the relay driving unit Sb, and the diode D3. Therefore, both ends of the relay drive section Sa are connected.

On the other hand, when a reverse power flow occurs, that is, when a current flows in the commercial power supply ACV in a direction to cancel the electromotive force generated by the commercial power supply ACV, the connection between the resistor R1 and the capacitor C is performed. The polarity of the voltage at the point and the polarity of the voltage at the connection point between the resistor R3 and the secondary winding of the current transformer T are not connected to the input terminal of the commercial power supply current monitoring unit 1 of the commercial power supply ACV. When the potential of the other pole is used as a reference, they have the same polarity. Accordingly, the anode of the diode D1 and the anode of the diode D2 have the same potential, and therefore, substantially no current flows through the relay driving section Sb. Therefore, both ends of the relay contact Sa are cut off.

Therefore, when the commercial power supply current monitoring unit 1 has the configuration shown in FIG. 2, the commercial power supply current monitoring unit 1 can avoid a situation where the power flow flows from the uninterruptible power supply 2 to the commercial power supply ACV.

When a current flows between a pair of input terminals provided in the relay driving unit Sb, the relay driving unit Sb controls the relay contact Sa so that both ends of the relay contact Sa are connected regardless of the direction of the current. May be used. in this case,
As shown in FIG. 3, one of the input terminals of the relay drive unit Sb is connected to one end of the resistor R2 that is not connected to the resistor R3, and the other of the input terminals of the relay drive unit Sb is connected to the other end. And the other end of the resistor R3 that is not connected to the current transformer T. And the diodes D1 to D4 are unnecessary.

As shown in FIG. 4, the power supply system includes n (n is an arbitrary positive integer) uninterruptible power supplies 2-1 to 2-1.
2-n and n number of power generation units 3-1 to 3-n may be provided. In this case, as shown in FIG.
To 2-n are connected to the output terminal of the commercial power supply current monitoring unit 1, and the other pole is connected to the commercial power supply A.
It is only necessary that the two terminals of the CV are connected to the other terminal that is not connected to the input terminal of the commercial power supply current monitoring unit 1. Also,
The synchronous input terminals of the uninterruptible power supplies 2-1 to 2-n only need to be connected to the commercial power supply current monitoring unit 1. Further, as shown in the figure, both poles of the input / output terminal of the uninterruptible power supply 2-k (k is an arbitrary positive integer equal to or less than n) are connected to the k-th load among the n external loads to be supplied with power. What is necessary is just to be connected to both ends of the load Z-k one-to-one. In addition, the positive electrode and the negative electrode of the charging input terminal of the uninterruptible power supply 2-k and the output terminal of the power generation unit 3-k may be connected to each other.

[0053]

As described above, according to the present invention, a power supply system capable of increasing the maximum value of a current that can be supplied without changing the structure of a transmission line for supplying power is realized. Is done.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a power supply system according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a modification of the commercial power supply current monitoring unit of the power supply system of FIG. 1;

FIG. 3 is a circuit diagram showing a configuration of a modification of the commercial power supply current monitoring unit of FIG. 2;

FIG. 4 is a block diagram showing a basic configuration of a modified example of the power supply system of FIG.

[Explanation of symbols]

 1 Commercial power supply current monitoring unit 2, 2-1 to 2-n Uninterruptible power supply 3, 3-1 to 3-n Power generation unit ACV Commercial power supply Z, Z-1 to Zn Load Sa Relay contact Sb Relay drive T Current transformer D1 to D4 Diode Dz1 to Dz4 Zener diode R1 to R4 Resistor C Capacitor

Claims (8)

[Claims] An electric power supplied from an external power source for supplying an AC power is transmitted through a transmission path for transmitting the electric power from the power source to an external load. A current monitoring unit that outputs current information indicating the magnitude of the current information, and acquires the current information output by the current monitoring unit, and determines whether the magnitude of the current indicated by the acquired current information exceeds a predetermined standby power supply start value. And a supplementary power supply for supplying power to the load when it is determined that the load is exceeded. 2. The supplementary power supply includes: a power generating means for generating electric power; and when the magnitude of the current indicated by the current information acquired by itself is determined to be equal to or less than the preliminary power supply start value, the power generating means The power supply system according to claim 1, further comprising: a reverse power transmission unit that supplies generated power to the power source. 3. The reverse power transmitting means converts the power stored by the power generating means, and has a phase substantially opposite to the phase of the current indicated by the current information, and the effective value of the current indicated by the current information is changed. The power supply system according to claim 2, wherein a current having an amplitude substantially equal to zero is generated, and the generated current is supplied to the power source. 4. The power generation means includes charging means for storing power generated by the power generation means, and the reverse power transmission means supplies the power stored by the charging means to the power source. Item 4. The power supply system according to item 2 or 3. 5. The replenishment power supply further includes a full charge determination unit that determines whether the charging unit is substantially in a fully charged state, wherein the charging unit is configured to determine a magnitude of a current indicated by the current information. When the supplementary power supply determines that does not exceed the reserve power supply start value, and when the full charge determination unit determines that the charging unit is not substantially in a fully charged state,
The self-generated power is stored, and the reverse power transmission unit determines that the supplementary power supply determines that the magnitude of the current indicated by the current information does not exceed the preliminary power supply start value, and that the full charge is performed. When the determining means determines that the charging means is substantially in a fully charged state,
The power supply system according to claim 4, wherein the power stored by the charging unit is supplied to the power source. 6. The current monitoring unit determines whether the polarity of the voltage at the other point with respect to one of the two predetermined points on the transmission path is the same for a predetermined time or more. Determining means for supplying power failure information indicating the determination result to the supplementary power supply; and when the determining means determines that the polarity of the voltage at the predetermined position is the same for more than the predetermined time, the transmission path is substantially changed. And a first interrupting means for interrupting the power supply. The replenishing power supply includes means for supplying power to the load when the power failure information output by the current monitoring unit is supplied. Item 6. The power supply system according to any one of Items 1 to 5. 7. The current monitoring unit determines whether or not the magnitude of the current detected by the current monitoring unit exceeds a predetermined maximum current value that is greater than the preliminary power supply start value. The power supply system according to any one of claims 1 to 6, further comprising a second blocking unit that substantially blocks the transmission line. 8. The external power source from the supplementary power source based on the direction of the current detected by the current monitor and the direction of the electromotive force generated by the external power source. And determining whether or not a current flowing in a direction for canceling the electromotive force is flowing, and when determining that the current is flowing, a third blocking means for substantially blocking the transmission line is provided. The power supply system according to claim 1.