JP2017063553A - Application method for power supply unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an application method for power supply unit with a storage battery, capable of achieving a peak shift and simple life determination of the storage battery with a simple configuration.SOLUTION: The application method for power supply unit includes: connecting a coil, a rectifier circuit and an inverter between a commercial power supply and a load connected with the commercial power supply and receiving power supply from the commercial power supply; further parallel-connecting the storage battery between the rectifier circuit, which is constructed by building a switching semiconductor with a reflux diode into a bridge, and the inverter; always switching the semiconductor for boosting; performing conversion into DC to charge the storage battery; performing conversion into AC using an inverter; supplying electric power to a load after step-down; at peaking-shift, stopping switching of the semiconductor; and supplying electric power from the storage battery to the load.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for operating a power supply device including a storage battery.

When supplying power to a load using a commercial power source, it is known that a peak shift of the commercial power source is performed for energy saving, and the commercial power source and a storage battery are used together for that purpose.

For example, for peak shift, a commercial power supply is connected to a load via a switch and a rectifier circuit, and a storage battery is connected in parallel between the rectifier circuit and the load via a step-up / down chopper to increase the power amount of the commercial power supply. It has been proposed to supply electric power from a storage battery to a load with a switch when sensing (Patent Document 1).

Depending on the state of charge, failure, or life of the storage battery used for these, there is a risk of output voltage drop, etc. Therefore, the replacement time of the storage battery is judged by measuring internal resistance, so that it does not hinder the power supply device It has also been proposed to do so (Patent Document 2).

JP-A-11-72254 JP 2010-127880 A

However, in these conventional power supply devices, it is necessary to control the commercial power supply in order to supply power from the battery power to the load via the inverter during the peak shift operation. In addition, a step-up / step-down chopper is required for peak shifting, and equipment for measuring internal resistance is required to monitor the state of the storage battery. there were.

The present invention solves these problems. In a power supply apparatus including a commercial power source, a rectifier circuit that rectifies the commercial power source and charges a storage battery, and an inverter that returns the current to an alternating current and supplies power to a load, the commercial power source and the rectifier are provided. Coils are arranged between the circuits, the rectifier circuit is made of a switching semiconductor, the power supply voltage is boosted by switching operation to charge the storage battery, and the power is supplied to the load via the inverter. Switching is stopped and power is supplied from a high-voltage storage battery to a load via an inverter.

By adopting such a configuration and operation method, the switching semiconductor is provided with a free-wheeling diode even when the battery life or trouble occurs and the predetermined power cannot be obtained during peak shift operation. Therefore, power before boosting is always applied to the circuit, and power supply to the load is continuously performed, so that there is no problem as a power supply device.
Furthermore, the lifetime of a storage battery can also be easily estimated by providing the monitoring apparatus which measures the discharge voltage and discharge time of a storage battery, and monitors the operation state of a storage battery.

According to the present invention, even if a malfunction occurs in the storage battery, a minimum power source is secured by the rectifier circuit formed by the freewheeling diode, and there is no trouble as a power supply device. Furthermore, if the operation state of the storage battery is measured, there is an effect that the life of the storage battery can be easily predicted.

It is a block diagram for demonstrating this invention embodiment.

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram for explaining an embodiment of the present invention. In the drawings, 1 is a commercial power source, 2 is a coil, 3 is a rectifier circuit in which four switching semiconductors each having a reflux diode are assembled in a bridge, 4 is a storage battery made of a lead storage battery, 5 is an inverter, and 6 is a load. The rectifier circuit 4 is a switching semiconductor provided with a freewheeling diode. For example, an IGBT (Insulated Gate Bipolar Transistor), an FET (field effect transistor), or the like is used, and these four are assembled in a bridge. These are connected to the commercial power source 1 in the order of the coil 2, the rectifier circuit 3, the inverter 5, and the load 6, and the storage battery 4 is connected in parallel between the rectifier circuit 3 and the inverter 5. In the figure, 7 is an electrolytic capacitor connected in parallel to the input side of the inverter 5, and 8 and 9 are capacitors connected in parallel to a coil connected on the output side of the inverter 5.

The power supply device configured in this manner always receives power from the commercial power source 1, and the switching semiconductor built in the bridge of the rectifier circuit 3 repeatedly turns on and off to rectify to direct current, and supplies power to the storage battery 4 for charging. However, it is converted into alternating current by the inverter 5 and power is supplied to the load 6. At this time, the output of the rectifier circuit 3 is boosted by the coil 2 by turning on and off the switching semiconductor of the rectifier circuit 3.

The reason is that when the switching semiconductor of the rectifier circuit 3 is turned off, the power of the commercial power supply is supplied via the freewheeling diode. However, when turned on, the power of the commercial power supply 1 does not flow into the rectifier circuit 3 due to the storage battery voltage. Is stored in the coil 2, and when the next switching semiconductor is off, the energy stored together with the power of the commercial power source is released and boosted. In order to repeat this, the storage battery 4 is charged at a high voltage.

The storage battery 4 itself used is also configured for high voltage. That is, when the voltage of the commercial power supply 1 is 200V, normally, 100 lead batteries having a voltage of 2V are connected in series to be 200V. However, in the present invention, the voltage is boosted. 115 lead acid batteries are connected in series to 230V.

In the inverter 5, the on / off ratio of switching is adjusted so that the output becomes 100V.

Such switching on / off is such that on / off of each switching semiconductor is controlled by the rectification control unit 10 connected to the rectification circuit 3 and the inverter control unit 11 connected to the inverter 5. In the figure, reference numeral 12 denotes a voltmeter connected to the output side of the inverter 5, which monitors the output voltage of the inverter 5. When the voltage fluctuates, the inverter controller 11 controls on / off of the inverter 5, and the output voltage is It is set to 100V.

And when the amount of electric power is measured with the watt-hour meter 13 connected to the commercial power source 1 side and the necessity of a peak shift arises, if the rectification control part 10 stops switching of the rectifier circuit 3, the commercial power source 1 will be Although the power is supplied to the rectifier circuit 3 without being boosted, the voltage of the storage battery 4 is as high as 230 V, so the storage battery 4 is discharged and the power is supplied to the load 6 via the inverter 5. Then, switching of the rectifier circuit 3 is started again after a predetermined time of 2 hours or 3 hours, and the consumption of commercial power can be suppressed by discharging the storage battery.
At this time, even if the storage battery is not able to obtain the predetermined power due to failure or life, the rectifier circuit that has stopped switching supplies power through the diode bridge, so power supply to the load is not possible. There is no interruption.

Thus, in the present invention, it is possible to switch to the peak shift operation simply by stopping the switching operation with a simple circuit configuration.

Furthermore, even if the storage battery is inadequate in capacity, failure, life, etc. when it shifts to peak shift operation, and the specified power cannot be obtained, the commercial power supply is always connected. Electric power can be supplied to the load from a commercial power source in the event of a momentary interruption.

Furthermore, a voltmeter 14 is connected to the output side of the storage battery to measure the discharge voltage of the storage battery, and a monitoring device 16 is provided for monitoring the operating state of the storage battery by adding a time measurement unit 15 until a predetermined voltage value is reached. Then, since the operation time of the storage battery 4 until it becomes a predetermined voltage value is known, and the life and deterioration state of the storage battery are known from the length of the operation time, there is an effect that the replacement time of the storage battery can also be determined.

Specifically, 200V is used as a commercial power source, and it is raised to about 270V by switching operation of the rectifier circuit. A lead storage battery in which 115 unit cells are connected in series is charged at about 2.4V / cell, and an AC is supplied by an inverter. The power is supplied to the load by reducing the voltage to 100V and the power consumption amount of the commercial power source becomes a predetermined value that may exceed the predetermined power amount contracted with the power company, and a peak shift is required. When this happens, switching of the rectifier circuit is stopped and power is supplied from the storage battery to the load. Since the output voltage of the storage battery at this time is usually 2 V per unit cell, 2 × 115 = 230 V. This storage battery voltage decreases with the discharge, and when the value measured by the voltmeter becomes about 205 V, the switching of the rectifier circuit is started again, and the charging of the storage battery and the power supply to the load are resumed.

The time to reach 205V depends on the power consumption of the load. For example, in a factory or the like, if the peak shift time is performed for 3 hours per day and the contracted power amount is not exceeded, a predetermined time is determined every day. If this is input to the rectification control unit 10, the peak shift operation is switched every day at the same time regardless of the watt-hour meter, and the operation is performed until the discharge voltage of the storage battery reaches 205V. If the monitoring device determines that the time to reach 205V is approaching 3 hours, investigate the cause, and if necessary, arrange and replace a new storage battery so that it can be used as a power supply. can do.

As described above, according to the present invention, the peak shift can be performed with a simple circuit configuration, the life of the storage battery can be easily predicted, and the battery can be operated without any trouble.

DESCRIPTION OF SYMBOLS 1 Commercial power source 2 Coil 3 Rectifier circuit 4 Storage battery 5 Inverter 6 Load 16 Monitoring device

Claims (2)

A coil, a rectifier circuit, and an inverter are connected between a commercial power source and a load connected to the commercial power source, and a storage battery is connected in parallel between the rectifier circuit and the inverter. The switching semiconductor is built in a bridge, which is normally boosted by switching the semiconductor, converted to direct current to charge the storage battery, converted to alternating current by an inverter, and stepped down to supply power to the load. A method of operating a power supply apparatus, characterized in that during a shift, semiconductor switching is stopped and power is supplied from a storage battery to a load.   The operation method of the power supply device according to claim 1, comprising a monitoring device that monitors an operation state of the storage battery, and replacing the storage battery according to the operation state.

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