JPH05211731A - Power supply - Google Patents

Abstract

PURPOSE:To supply a stable power optimal to a load by retrieving a data base through inputting power characteristic parameters required by the load and the sort of the load via interface, by automatically setting the control and protection standard of a power converter and by converting power CONSTITUTION:An AC power 1 is rectified 3 for floating-charge of a battery 2, converted into VVVF AC by inverter 4 and supplied to a load 9 via AC filter 5 and change-over switch 7. Also, auxiliary AC power 6 is supplied to the load 9 via the change-over switch 8 so that the title apparatus is made uninterruptible. A power characteristic parameter such as a waveform distortion required by the load 9 and the magnitude of voltage variation is inputted to a computer 22 from a man-machine interface 21 such as keyboard. The computer 22 retrieves the power characteristic parameter, automatically sets an output waveform standard optimal to the power characteristic parameter and the malfunction detection level of output voltage and controls the inverter 4 via controller 23. Thus, it is possible to correspond to various ' load characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power source for supplying stable AC power or DC power to a load by using a first power source such as a commercial power source or a second power source having an energy source such as a storage battery or a fuel cell as an input. The present invention relates to a power supply device including a conversion device.

[0002]

2. Description of the Related Art As a power source for an important load system such as a computer, an uninterruptible power supply unit (hereinafter referred to as UPS) which supplies stable AC power from a storage battery as a power source even when the AC input power source fails or has a momentary voltage drop. It is becoming widely used. In particular, since the UPS has been used in all fields in recent years, the load of the UPS has been diversified, and the required power supply characteristics are gradually changing for each load. FIG. 5 is a block diagram showing an example of a conventional UPS of this type.

In the figure, 1 is an AC input power source, 2 is a storage battery, 3 is a rectifier for converting the AC input into DC and charging the storage battery 2, 4 is an inverter, 5 is a rectangular wave output of the inverter 4 is a sine wave. An AC filter to be improved, 6 is a backup AC power source, 7 and 8 are semiconductor changeover switches (thyristor switches), and 9 is a load of a computer or the like. Normally, the load is supplied to the load 9 by the inverter 4 via the AC filter 5 and the changeover switch 7, and when the inverter 4 fails or the device is inspected for maintenance, the changeover switch 7 changes to the changeover switch 8.
Switch to the inverter 4 again after failure recovery or maintenance inspection after switching to
By switching to the above, the power can be continuously supplied to the load 9.

When the load 9 is a computer, its power supply section is often composed of a non-linear circuit called a capacitor input rectifier circuit, and has a load current containing many harmonics. In addition, many of the loads of computers and the like generally require (1) sinusoidal voltage without distortion as required characteristics for the power supply. (2) The voltage fluctuation is less than a predetermined value (eg ± 10
Therefore, the UPS controls the output of the inverter 4 to a characteristic that sufficiently satisfies the above-mentioned required characteristics by a control circuit (not shown).

[0005]

However, regarding the cooperation with the required characteristics of the load, the technical problems of UPS are summarized as follows in accordance with the recent widespread spread of UPS in various fields.

(1) The load of the UPS is diversified, and the required characteristics are slightly different depending on the load, and the required characteristics are becoming clear. Therefore, the UPS has a unified characteristic like the conventional one. It is necessary not only to make the characteristics according to the load.

(2) For the output of UPS, the protection which is coordinated with the limit allowed by the load is taken into consideration, and the storage battery and the like are used up to the limit allowed by the load. Therefore, it is necessary to make the UPS system highly economical.

The present invention has been made in view of the above points, and in a power supply device composed of a power converter for supplying stable power to a load, the power supply device has an output characteristic corresponding to the required characteristic of the load and a storage battery. An object of the present invention is to provide a highly economical power supply device capable of drawing out the capabilities of the components of the equal power supply device to the full.

[0009]

In order to achieve the above-mentioned object, the present invention uses a first power source such as a commercial power source or a second power source having a storage battery, a fuel cell or the like as an energy source as a stable input. In a power supply device provided with a power converter for supplying AC power or DC power to a load, interface means for inputting a power supply characteristic parameter required by the load or a type of load, and power supply characteristic parameter input through the interface means Alternatively, a database is searched from the load data, and control means for the power conversion device and calculation means for automatically setting protection parameters, and output control of the power conversion device based on the control parameters and protection parameters automatically set by the calculation means It is characterized by comprising a control means.

[0010]

In the power supply device having such a configuration, the optimum parameter for controlling and protecting the output is calculated from the required characteristic parameter of the load or the load data inputted through the interface means by the calculation means based on the database. The power converter can be controlled so that the output characteristics are automatically set and the output characteristics correspond to the load.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the block diagram of FIG. In FIG. 1, the constituent elements denoted by the same reference numerals as those in FIG. 5 are constituent elements having the same functions as those in FIG. 5, and description thereof will be omitted.

In FIG. 1, reference numeral 21 denotes a man-machine interface (hereinafter simply referred to as M) such as a keyboard for inputting power supply characteristic parameters such as waveform distortion and voltage fluctuation required by the load 9.
MI), 22 is a control computer for automatically setting optimum parameters such as output waveform reference and output voltage abnormality detection level for the inverter 4 and protection parameters by searching a database from power source characteristic parameters input through the MMI 21, 23 Is an inverter control circuit for controlling the inverter 4 based on the control parameters and protection parameters automatically set by the control computer 22.

Next, the operation of the embodiment of the present invention constructed as above will be described. 2 shows the control computer 2
6 is a flowchart for explaining the operation of No. 2. The control computer 22 includes a database of control references of the inverter 4 corresponding to combinations of power supply characteristics such as waveform distortion, waveform peak value, and voltage fluctuation. Then, the database is searched to obtain a control reference such as an output voltage waveform for the inverter 4. At the same time, optimum parameters are also obtained for protection detection parameters such as output voltage abnormality detection of the inverter 4. In this way, the control computer 22
The inverter control circuit 23 controls the output of the inverter 4 based on the control parameter and the protection parameter obtained by As a result, the output of the inverter 4 is optimally controlled so as to have a characteristic corresponding to the load 9 without being limited to a unitary characteristic as in the conventional case.

With respect to the protection parameter, for example, the detection of the output voltage drop is conventionally unitarily set to -10% of the rating, but depending on the load 9, up to -15% of the rating can be allowed. For example, the discharge lower limit voltage of the battery 2 at the time of power failure of the AC input power supply 1 can be lowered accordingly, so that the discharge capacity of the storage battery 2 can be more fully drawn and the operating range can be expanded.

As described above, in this embodiment, the control parameter and the protection parameter corresponding to the required power supply characteristic of the load are obtained, and the inverter 4 is controlled on the basis of the control parameter and the protection parameter to obtain the characteristic corresponding to the load. At the same time, it is possible to make full use of the capabilities of the constituent elements of the power supply device such as the storage battery, and to construct a power supply device with high economic efficiency. As the operation of the control computer 22 of the embodiment of FIG. 1, the type of the load 9 itself is inputted through the MMI 21 as shown in FIG. 3 to the contents of FIG. 2, and the control parameters are similarly stored in the database stored in the control computer 22 in advance. If the protection parameters are obtained, the system becomes easier to use.

Further, since the load 9 is actually composed of a plurality of loads in many cases, the required power source characteristics for each load are input to the control computer 22 as shown in FIG. It is also possible to configure so as to obtain comprehensive optimum control parameters and protection parameters that best suit the required power supply characteristics for each load. In this case, each load may be prioritized and the weight for each load may be input to perform so-called fuzzy control-like processing (membership function).

Further, in the embodiment of FIG. 1, the AC output power supply device by the inverter 4 is used, but the same applies to the DC output power supply device by another type of power converter such as a chopper if the present invention is applied. The effect is obtained.

[0018]

As described above, according to the present invention, in a power supply device composed of a power conversion device for supplying stable power to a load, a high-quality product corresponding to the required power supply characteristics of diversified loads can be obtained. It is possible to provide a highly economical power supply device that has output characteristics and can fully utilize the capabilities of the constituent elements of the power supply device such as a storage battery.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the control computer of the embodiment shown in FIG.

FIG. 3 is a flowchart for explaining the operation of a control computer as another embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of the control computer as still another embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration example of a conventional power supply device.

[Explanation of symbols]

 1 ... AC input power supply 2 ... Storage battery 3 ... Rectifier 4 ... Inverter 5 ... AC filter 6 ... Spare AC power supply 7, 8 ... Changeover switch 9 ... Load 21 ... Man-machine interface 22 ... Control computer 23 ... Inverter control circuit

Claims (2)

[Claims] 1. A power conversion device for supplying a stable AC power or DC power to a load by inputting a first power supply such as a commercial power supply or a second power supply using a storage battery, a fuel cell or the like as an energy source. In the power supply device, interface means for inputting a power supply characteristic parameter or load type required by the load, control parameters for the power conversion device by searching a database from the power supply characteristic parameter or load data input via the interface means A power supply device comprising: arithmetic means for automatically setting a protection parameter; control means for automatically controlling the output of the power converter based on the control parameter and the protection parameter automatically set by the arithmetic means. 2. A power converter for supplying stable AC power or DC power to a plurality of loads by inputting a first power supply such as a commercial power supply or a second power supply using a storage battery, a fuel cell or the like as an energy source. In a power supply device comprising: an interface unit for inputting required power supply characteristic parameters for each load or a type of each load; a database is searched from required power supply characteristic parameters for each load or load data input via the interface unit. Computation means for automatically setting comprehensive control parameters and protection parameters for the power converter, control for controlling output of the power converter based on the comprehensive control parameters and protection parameters automatically set by the computing means A power supply device comprising means.