JP2006271097A - Power supply controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply controller which can avoid increase in power cost, by supplying power for temporary overload from a different system so that it is sufficient that a power supply be required to assure power supply of load current for steady-state operation. <P>SOLUTION: In an uninterruptible power supply 10 where AC power from a commercial power supply P is converted via a rectifier 11 into DC power being stored in a storage battery 12; and then the stored power is converted through an inverter 13 into AC power and outputted, when the fact that a contract current level I is exceeded is detected, based on detection information from a sensor 14 for detecting the current level of commercial power being supplied from the commercial power supply P to load units 101-103, switches 21-24 are switched by a control section 25, before a main leakage breaker 120 functions and power is supplied from the commercial power supply to the load units 101 and 102, and from the storage battery to the load unit 103. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power supply control device, and more particularly to a device capable of avoiding inconvenience due to a temporary overload when a load current supplied to the load device is temporarily overloaded.

  Conventionally, power factories (current values) supplied from commercial power sources have been negotiated in advance in factories that use load devices such as electrical equipment, so that the contracted power value (arranged current value) is not exceeded. Use a load device.

  On the other hand, in each household that uses a load device such as a home appliance, the power supplied from the commercial power source is set in advance according to the load current consumed by the load device, and this set power range (decision) Use the load device within the current value.

  By the way, these load devices function by receiving power supply from a commercial power supply, but depending on the function of the load device, the influence of voltage fluctuations may be large. In such a load device, when a voltage drop instantaneously (including a stop) occurs in the power supplied from the power supply, the load operation is interrupted.

  For this reason, in such a load device, an uninterruptible power supply (UPS: Uninterruptible Power) that enables electric power to be consumed for a certain period of time by storing electric energy before a voltage sag occurs. System) (see, for example, Patent Documents 1 and 2). Of these, the uninterruptible power supply described in Document 1 is a device that performs an important load operation or a general load operation so that the necessary power can be supplied with high reliability when a voltage sag occurs. In order to suppress power consumption by unimportant load devices, the load devices that perform general load operations are removed from the power supply target in the event of an instantaneous drop. Has been.

In addition, the uninterruptible power supply is devised to supply the stored power to the load side when a voltage drop occurs in the power supplied from the power supply due to temporary overload exceeding the power supply capacity. Some have been proposed (see, for example, Patent Documents 3 and 4).
JP 2003-204625 A JP 2003-274559 A JP 2002-95183 A JP 2003-52134 A

  Here, in factories that define contract power, for example, when the load current temporarily rises (overcurrent occurs) due to an overload such as when the load device is started up, the contract power is exceeded. There is. In this case, it is necessary to take measures such as increasing the contract power to be used steadily so as to cover the temporary increase in load current, or stopping the operating load device only at that time.

  In addition, if the breaker functions frequently due to an overload such as when the load device is started up in a household where the power supply is cut off by a breaker or the like when the available set power is exceeded, It is necessary to take measures such as increasing the set power according to the temporary load current.

  However, since it is costly and wasteful to be able to use a large load current unnecessarily due to such a temporary overcurrent, power supply control that can avoid inconvenience due to the temporary overload It is desirable to implement the device.

  On the other hand, the uninterruptible power supply devices described in Documents 1 and 2 cannot cope with the occurrence of temporary overload, but the uninterruptible power supply devices described in Documents 3 and 4 are temporary. When an overload occurs, the stored power can be supplied to the load side, and it can be considered to be effectively used as a power supply control device.

  However, in the uninterruptible power supply devices described in Documents 3 and 4, since the stored power is output so as to be superimposed on the power supplied from the power source, it is necessary to synchronize the power source power and the stored power. For this reason, in this uninterruptible power supply device, there is a problem that complicated control and parts are required and the cost becomes high.

  Therefore, the present invention secures the power supply of the load current according to the steady operation from the power supply by realizing a simple power supply from a different system different from the power supply normally used for a temporary overload. It is an object of the present invention to provide a power supply control device that is sufficient to avoid an increase in cost of electric power.

  A first invention of a power supply control device that solves the above problems includes a supply path for supplying power from a power source to a plurality of load devices, power storage means for storing power from the power source as electric energy, Supply means for supplying the stored energy as supply power to the load device, measurement means for measuring the current value of the load power supplied from the power source to the load device, and some load devices based on the measurement value by the measurement means Switching control means for executing load variation countermeasure control for switching the power supply source from the power source to the power storage means.

  In this invention, load fluctuation countermeasure control is executed based on the measurement result (measurement current value) of the load current supplied from the power supply, so that the power supply source that supplies power to the load device can store power stored in a system different from the power supply. For example, when a temporary overcurrent occurs after switching to the means side, the stored power in the power storage means is supplied to some load devices. Therefore, it is possible to avoid an inadvertent increase in the load current supplied from the power source, and to prevent the power supplied from the power source from becoming larger than the load current assumed in advance. it can.

  According to a second aspect of the power supply control apparatus for solving the above problems, in addition to the specific matters of the first aspect, a part of load apparatuses for switching the power supply source from the power source to the power storage means is set by the switching control means. It has a setting means.

  According to the present invention, a load device in which the power supply source is switched to the power storage means side of a system different from the power source can be set in advance by load fluctuation countermeasure control according to the load current from the power source. Therefore, it is possible to avoid that the load device that is affected by the operation that is disconnected from the supply path on the power source side and switched to the power storage means side is inadvertently made symmetrical with the switching of the power supply source. It is possible to prevent the normal operation of the camera from being hindered.

  According to a third aspect of the power supply control apparatus for solving the above-mentioned problems, in addition to the specific matter of the first or second aspect of the invention, the third aspect of the invention includes a detection unit that detects the presence or absence of power supply from a power source. The means is characterized in that when the detection means detects the occurrence of a power failure where the power supply from the power supply is interrupted, the power supply countermeasure control for switching the power supply source of all load devices from the power supply to the power storage means is executed. is there.

  In the present invention, when a power failure occurs, the power supply source of all the load devices can be switched from the power source side to the power storage means side, and the operation of all the load devices can be maintained. Therefore, load fluctuation countermeasure control that avoids the influence of overcurrent and power failure countermeasure control that avoids the influence of power outage can be executed together, and most of the components of the uninterruptible power supply can be shared at low cost. A fluctuation countermeasure control function can also be realized.

  As described above, according to the present invention, by effectively using the power storage unit of another system together with the power source in accordance with the load current when operating the load device, the internal power storage unit in the power storage unit is generated when a temporary overcurrent occurs. By using the stored power, it is possible to realize the stability of the load current supplied from the power source. Therefore, it is sufficient to secure a load current corresponding to the steady operation of the load device from the power source, and avoiding the cost of unnecessarily increasing the power that can be received from the power source. Can do. Moreover, by making it possible to use also as an uninterruptible power supply, the uninterruptible power supply can be enhanced at low cost.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of the invention will be described with reference to the drawings. 1 to 4 are diagrams showing an uninterruptible power supply device with a load variation countermeasure control function, which is an example of an embodiment of a power supply control device according to the present invention.

  In FIG. 1, an uninterruptible power supply 10 with a load fluctuation countermeasure control function is installed on a distribution board 100 that distributes power supplied from a commercial power source P to each of load apparatuses 101 to 103 used in a factory, home, or the like. The uninterruptible power supply 10 is connected to the power line 110 of the distribution board 100, rectifies the AC power from the commercial power source P into DC power, and outputs the DC power from the rectifier 11. It is connected to a storage battery (storage means) 12 that stores the power and outputs the stored power at a desired timing, and a branch line (supply path) 113 of the distribution board 100 to convert the DC power from the storage battery 12 into AC power. And an inverter (supply means) 13 for outputting to the branch line 113 after conversion.

  As a result, the uninterruptible power supply 10 stores DC power in the storage battery 12 via the rectifier 11 in a steady state, and converts the stored power into AC power via the inverter 13 at a desired timing. In addition, power can be supplied to the load devices 101 to 103 as a power supply device separate from the commercial power supply P.

  The uninterruptible power supply 10 includes a current detection sensor (measuring means) 14 that detects a current value i of power supplied from the commercial power source P that flows through the power line 110 of the distribution board 100, and a commercial of the distribution board 100. A changeover switch (SW1) 21 that is interposed in a power line 110 subsequent to the main earth leakage breaker (ELB) 120 disposed at the power receiving port and switches connection / disconnection of power from the commercial power source P at high speed, Fast connection and disconnection of the power supply branched from the commercial power supply P, which is interposed in the branch line 113 in front of the branch breaker (NFB3) 123 arranged at the power supply port to the load device 103 of the switchboard 100 The switch (SW2) 22 for switching to the power supply, the branch line 113 between the switch 22 and the branch breaker 123, and the inverter 13 are provided to supply power from the storage battery 12. A change-over switch (SW3) 23 that switches connection / disconnection at high speed, and a power supply line 110 between the main earth leakage breaker 120 and the change-over switch 21 and the rectifier 11 are connected to the storage battery 12 at high speed. A changeover switch (SW4) 24 for switching to and a control unit (control means) 25 for controlling the changeover of these changeover switches 21 to 24 based on information detected by the current detection sensor 14 are provided.

  As a result, the control unit 25 of the uninterruptible power supply apparatus 10 replaces the commercial power supply P with the load apparatuses 101 to 103 in the event of a power failure when the power supply from the commercial power supply P is interrupted based on the detection information from the current detection sensor 14. When an overload exceeding a power supply function (power failure countermeasure control function) or an amount of electric power (current value) set (arranged) so as to be received from the commercial power supply P occurs in the load devices 101 to 103, the commercial power supply A function (load fluctuation countermeasure control function) for supplying power to the load devices 101 to 103 is operated together with P.

  The current detection sensor 14 is a clamp-type current transformer (CT) that forms a coil around the power supply line 110. The storage battery 12 is constructed by, for example, a capacitor or a battery, and stores power supplied from the commercial power source P as electric energy that can be supplied to the load devices 101 to 103. However, the storage battery 12 is not limited to this, and depends on the inertia of the flywheel. A power storage device that stores electrical energy may be used. Further, a branch breaker (NFB1) 121 is interposed in the branch line 111 in the previous stage of the power supply port to the load device 101 of the distribution board 100. Similarly, the branch circuit breaker (NFB1) 121 is installed in the previous stage of the power supply port to the load device 102. A branch breaker (NFB2) 122 is interposed in the branch line 112.

  Specifically, the control unit 25 is constructed by a CPU (Central Processing Unit) that executes various control operations in accordance with a control program stored in a memory (not shown), and switches based on information detected by the current detection sensor 14. Power failure countermeasures for switching the power supply source to all of the load devices 101 to 103 to the storage battery 12 when it is detected that a power failure has occurred in the commercial power source P by controlling the on / off switching of the switches 21 to 24 When the control is executed or the occurrence of an overload that exceeds the amount of power (arranged current value I) that has been negotiated with the power company in advance for the power supplied from the commercial power source P is detected, the commercial power source P From the power supply port of the branch line 113 interposing the changeover switch 22 while supplying power to the load devices 101 and 102. Performs load fluctuation countermeasure control for supplying stored power in the battery 12. In other words, the control unit 25 is designed to execute a load variation countermeasure control and a power failure countermeasure control by constituting a switching control means and a detection means. Further, here, the setting means for setting the load device 103 as the target for switching the power supply source from the commercial power source P to the storage battery 12 by load fluctuation countermeasure control connects the load device 103 to the power supply port of the branch line 113. However, the present invention is not limited to this, and for example, the load devices 101 and 102 may be configured to be selectable and settable by, for example, arranging a changeover switch on the branch lines 111 and 112. Absent.

  For example, in the control unit 25, the detection information by the current detection sensor 14 indicates that the amount of electric power (current value i) supplied from the commercial power source P is equal to or less than the agreed current value I that has been negotiated with the power company in advance. In this case, as shown in FIG. 2, by turning on the changeover switches 21, 22, and 24 and turning off the changeover switch 23, the power supply path from the storage battery 12 to the load devices 101 to 103 remains open. Then, electric power is supplied from the commercial power supply P to the load devices 101 to 103 to maintain the power storage in the storage battery 12 via the rectifier 11 while continuing the load operation.

  In addition, when the control unit 25 detects from the detection information from the current detection sensor 14 that a power failure occurs in which the power supply of the commercial power supply P is interrupted, the selector switches 22 and 24 are immediately turned on as shown in FIG. The switch 21 is turned off and the switch 23 is turned on to open the power supply path from the commercial power source P to the load devices 101 to 103 (disconnect the commercial power source P) and from the storage battery 12 to the load device. The power supply path to 101 to 103 is connected. By this power failure countermeasure control, the uninterruptible power supply 10 starts power supply from the storage battery 12 to the load devices 101 to 103 via the inverter 13 and continues its load operation, and the power supplied from the storage battery 12 is supplied from the commercial power supply P. Backflow to the side can be restricted. Thereafter, when the control unit 25 detects from the detection information by the current detection sensor 14 that the power supply of the commercial power supply P has been resumed normally, the changeover switches 22 and 24 remain on and the changeover switch 21 remains on. 2 is turned on and the changeover switch 23 is turned off to return to the steady state shown in FIG. 2, and the supply of power from the commercial power supply P to the load devices 101 to 103 is resumed to continue the load operation via the rectifier 11. The power storage to the storage battery 12 is resumed.

  Thereby, this uninterruptible power supply 10 switches the electric power supply source of all the load apparatuses 101-103 from the commercial power P side to the storage battery 12 side at the time of a power failure like the general uninterruptible power supply apparatus, The load operation can be continuously maintained.

  Furthermore, when the control unit 25 detects from the detection information by the current detection sensor 14 that the amount of power supplied from the commercial power source P exceeds the current value I that has been negotiated with the power company in advance. As shown in FIG. 4, the power supply path from the commercial power supply P to the load devices 101 and 102 is established by turning off the changeover switches 22 and 24 and turning on the changeover switch 23 while the changeover switch 21 is on. While maintaining, the power supply path from the commercial power supply P to the storage battery 12 via the load device 103 and the rectifier 11 is opened (the commercial power supply P is disconnected) and the power supply path from the storage battery 12 to the load apparatus 103 is connected. By this load fluctuation countermeasure control, the uninterruptible power supply 10 supplies electric power from the commercial power supply P to the load apparatuses 101 and 102 to continue the load operation, and supplies power from the storage battery 12 to the load apparatus 103 via the inverter 13. While starting and continuing the load operation, the power storage to the storage battery 12 via the rectifier 11 is interrupted. After this, when the control unit 25 detects that the amount of power consumed by the load devices 101 and 102 has decreased below a preset current value based on the detection information by the current detection sensor 14, for example, Alternatively, when a preset period (for example, a power supply time that does not use up the storage capacity of the storage battery 12) has elapsed, the changeover switch 21 and the changeover switches 22 and 24 are turned on while the changeover switch 21 remains on. By turning off the switch 23, the steady state shown in FIG. 2 is restored, the power supply from the commercial power source P to all of the load devices 101 to 103 is resumed, and the load operation is continued to the storage battery 12 via the rectifier 11. Resumes power storage. Note that, as a condition for returning from the load fluctuation countermeasure control to the steady state, the case where the amount of power consumed by the load devices 101 and 102 drops below the set current value I or the case where the set period has elapsed is given as an example. However, the present invention is not limited to this. When the amount of electric power (current value) consumed by the load device 103 is detected and the sum of the current value detected by the current detection sensor 14 becomes equal to or less than the agreed current value I, You may make it restart the electric power supply from the commercial power supply P to all the load apparatuses 101-103.

  Here, after the supply power from the commercial power source P exceeds the agreed current value I, a part of the supply source of the supplied power is switched to the storage battery 12, but the main leakage breaker 120 has the agreed current value I It does not operate at the moment when it exceeds the limit, but functions when the power supply of the excess power amount continues for a certain period. Therefore, it is sufficient that the load variation countermeasure control is started by then.

  Thus, the uninterruptible power supply 10 includes, for example, a load device 101 as an air conditioner device, a load device 102 as a cooking device group such as a microwave oven used in a kitchen, and a load device 103 as a television device used in a living room. When the load device 101 temporarily consumes a large amount of power to bring it to a comfortable room temperature immediately after the power is turned on, the power consumption of the load devices 102 and 103 that are simultaneously operated is added. When the determined current value I is exceeded, the operation of some of the load devices 103 is covered by the stored power of the storage battery 12 so that the power supplied from the commercial power source P does not exceed the determined current value I. The main earth leakage breaker 120 of the distribution board 100 is operated, and the power supply from the commercial power source P is forcibly cut off, and the load devices 101 to 103 are Dynamic can be prevented that would be an emergency stop.

  Therefore, it is possible to prevent the operation of the load devices 101 to 103 from being stopped when the main earth leakage breaker 120 of the distribution board 100 works and the power supply from the commercial power supply P is forcibly cut off. Therefore, it is possible to avoid redoing various settings of each device or losing cooking during heating.

  Thus, in this embodiment, according to the load current consumed by the load devices 101 to 103, the stored power in the storage battery 12 used when functioning as an uninterruptible power supply device is effectively added to the commercial power supply P. The load device 101 can be used with the power supplied from the commercial power source P even during a period in which the overcurrent of the load devices 101 to 103 temporarily exceeds the current value I determined with the power company due to overload. The load device 103 can be operated with the stored power of the storage battery 12 and the power supplied from the commercial power source P can be suppressed to the determined current value I or less. Therefore, the amount of power received from the commercial power source P can be stabilized, and the current value I of the amount of power necessary for operation of the load devices 101 to 103 that operate in a steady manner is determined as the amount of power (current value) received from the power company. Can do. As a result, it is possible to receive an unnecessarily large current value I, and there is no need to avoid the operation stop of the load devices 101 to 103, and the useless cost as the decided current value I corresponding to the operation of the load devices 101 to 103 is wasted. Can be avoided.

  In addition, by setting (fixing) the power supply source from the commercial power supply P to the storage battery 12 to be set (fixed) in the load device 103, other than the load device 103 cannot be stably operated by the switching operation. Can be avoided.

  Furthermore, this uninterruptible power supply 10 can be configured to be able to perform load fluctuation countermeasure control only by adding a changeover switch to a general uninterruptible power supply, and is also inexpensive because it can be used for most of the components. Can be produced.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the uninterruptible power supply with a load fluctuation countermeasure control function which is an example of one Embodiment of the electric power supply control apparatus which concerns on this invention, and is a block diagram which shows the schematic whole structure. It is a conceptual diagram which shows the electric power supply path | route at the time of the steady state. It is a conceptual diagram which shows the electric power supply path | route at the time of the power failure generation | occurrence | production. It is a conceptual diagram which shows the electric power supply path | route at the time of the overload occurrence.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Uninterruptible power supply with load fluctuation countermeasure control function 11 ... Rectifier 12 ... Storage battery 13 ... Inverter 14 ... Current detection sensor 21-24 ... Changeover switch 25 ... Control unit 100 ... Distribution board 101 ˜103 …… Load device 110 …… Power line 111˜113 …… Branch line 120 …… Main circuit leakage breaker 121˜123 …… Branch line P …… Commercial power supply

Claims (3)

  A supply path for supplying power from the power source to the plurality of load devices, a power storage means for storing the power from the power source as electrical energy, a supply means for supplying the stored energy in the power storage means to the load device as supply power, Measuring means for measuring the current value of the load power supplied from the power supply to the load device, and load fluctuation countermeasure control for switching the power supply source of some load devices from the power supply to the power storage means based on the measurement value by the measurement means And a switching control means for executing the power supply control device.   The power supply control device according to claim 1, further comprising setting means for setting a part of load devices for switching the power supply source from the power source to the power storage means by the switching control means. Having detection means for detecting the presence or absence of power supply from the power source;
The switching control means executes a power failure countermeasure control for switching the power supply sources of all load devices from the power supply to the power storage means when the detection means detects the occurrence of a power failure in which the power supply from the power supply is interrupted. The power supply control device according to claim 1 or 2.

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