CN112703628A

CN112703628A - Power supply system, diagnostic device, and uninterruptible power supply device

Info

Publication number: CN112703628A
Application number: CN201980059556.9A
Authority: CN
Inventors: 河原洋平; 高桥宏文; 米元雅浩; 武田贤治
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2018-12-21
Filing date: 2019-10-15
Publication date: 2021-04-23
Also published as: JP2020102343A; WO2020129378A1; JP7149836B2

Abstract

The invention aims to accurately diagnose the capacity deterioration of a battery while ensuring the standby power. The power supply system is provided with a uninterruptible power supply device (102) having a rechargeable battery (204) and a diagnostic device (104) for diagnosing the capacity deterioration of the rechargeable battery of the uninterruptible power supply device, wherein the uninterruptible power supply device operates in a normal mode in which the rechargeable battery can be charged to a first state of charge and in a diagnostic mode in which the rechargeable battery can be charged to a second state of charge higher than the first state of charge, the diagnostic device switches the uninterruptible power supply device from the normal mode to the diagnostic mode, and diagnoses the capacity deterioration of the rechargeable battery of the uninterruptible power supply device using a capacity region between the first state of charge and the second state of charge.

Description

Power supply system, diagnostic device, and uninterruptible power supply device

Technical Field

The invention relates to a power supply system, a diagnostic device and a uninterruptible power supply device.

Background

The uninterruptible power supply device is a power supply device capable of supplying stable power to a server and other load devices by using power stored in a rechargeable battery at the time of a failure such as a power failure. Although it is mainstream to use a uninterruptible power supply device such as a lead storage battery as a rechargeable battery, in recent years, an uninterruptible power supply device using a small-sized and lightweight lithium ion battery as a rechargeable battery has also begun to be widespread.

In order to reliably operate the uninterruptible power supply device in the event of a failure, a diagnostic device for diagnosing the state of the rechargeable battery is provided in addition to the periodic inspection of the rechargeable battery. When the rechargeable battery is deteriorated, the internal resistance increases, and the full charge capacity decreases, which results in performance degradation. Therefore, in order to determine whether or not the desired power can be supplied to the load device, it is necessary to grasp a performance change accompanying deterioration of the rechargeable battery.

Conventionally, as a diagnostic device for a rechargeable battery, a device for diagnosing the degree of deterioration from the internal resistance value of the rechargeable battery has been proposed (for example, see patent document 1). The diagnostic device described in patent document 1 calculates an internal resistance value of the secondary battery by pulse-discharging the secondary battery at a rated current, and diagnoses the degree of deterioration of the secondary battery based on the internal resistance value.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2000-121710

Disclosure of Invention

Problems to be solved by the invention

However, since the uninterruptible power supply unit differs depending on the installation environment in the case of an instantaneous power failure and the case of a power failure, a large individual difference occurs in capacity deterioration depending on the installation environment. The diagnostic device described in patent document 1 predicts deterioration based on the internal resistance value of the rechargeable battery, and therefore cannot accurately diagnose actual capacity deterioration corresponding to the individual difference. Therefore, there is a possibility that the backup power required by the load device cannot be reliably secured at the time of power failure.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power supply system, a diagnostic device, and a uninterruptible power supply device, which can accurately diagnose capacity deterioration of a battery while securing backup power.

Means for solving the problems

An electric power system according to an aspect of the present invention includes: a uninterruptible power supply device having a rechargeable battery; and a diagnostic device that diagnoses deterioration in capacity of a rechargeable battery of the uninterruptible power supply device, wherein the uninterruptible power supply device operates in a normal mode in which the rechargeable battery can be charged to a first state of charge and a diagnostic mode in which the rechargeable battery can be charged to a second state of charge higher than the first state of charge, the diagnostic device switches the uninterruptible power supply device from the normal mode to the diagnostic mode, and diagnoses deterioration in capacity of the rechargeable battery of the uninterruptible power supply device using a capacity region between the first state of charge and the second state of charge.

Effects of the invention

According to the present invention, by using the capacity region between the first state of charge and the second state of charge, it is possible to actually discharge the secondary battery of the uninterruptible power supply unit while securing the backup power, and it is possible to diagnose the capacity deterioration of the secondary battery with high accuracy. Other features relating to the present invention will be apparent from the description of the present specification and the accompanying drawings. Problems, structures, and effects other than those described above will be apparent from the following description of the embodiments.

Drawings

Fig. 1 is a configuration diagram of a power supply system of the first embodiment.

Fig. 2 is a configuration diagram of the uninterruptible power supply unit according to the first embodiment.

Fig. 3 is a configuration diagram of the rechargeable battery according to the first embodiment.

Fig. 4 is a control block diagram of the diagnostic device of the first embodiment.

Fig. 5 shows an example of the state of charge of the uninterruptible power supply unit in the normal mode according to the first embodiment.

Fig. 6 shows an example of the state of charge of the uninterruptible power supply unit in the diagnosis mode according to the first embodiment.

Fig. 7 is a time chart of the capacity deterioration diagnosis process according to the first embodiment.

Fig. 8 is a time chart of another diagnosis process of capacity deterioration according to the first embodiment.

Fig. 9 shows an example of the state of charge of the uninterruptible power supply unit in the diagnosis mode according to the second embodiment.

Fig. 10 is a configuration diagram of a power supply system of the third embodiment.

Fig. 11 is a configuration diagram of a power supply system of the fourth embodiment.

Detailed Description

[ first embodiment ]

Hereinafter, a power supply system according to a first embodiment will be described with reference to the drawings. Fig. 1 is a configuration diagram of a power supply system of the first embodiment. The power supply system is interposed between a power system 101 such as a commercial power supply and a load device 103 to which power from the power system 101 is supplied. The power supply system is provided with a plurality of uninterruptible power supply units 102 having rechargeable batteries 204 (see fig. 2), and a diagnostic unit 104 for diagnosing the capacity performance of the rechargeable batteries 204 of the uninterruptible power supply units 102. In this power supply system, electric power from the power system 101 is supplied to the load device 103 at ordinary times, and when power is interrupted, the amount of stored electricity in the rechargeable batteries 204 of the plurality of uninterruptible power supply devices 102 is used to supply electric power to the load device 103.

In the uninterruptible power supply devices 102, the rechargeable battery 204 is charged with electric power from the power system 101 until a predetermined State of Charge (SOC). The diagnostic device 104 has a capacity diagnostic function for the rechargeable battery 204 of the uninterruptible power supply device 102 and a charge/discharge control function for the rechargeable battery 204 of the uninterruptible power supply device 102. Although an example in which the diagnostic device 104 is provided outside the uninterruptible power supply device 102 will be described below, the diagnostic device may be provided inside the uninterruptible power supply device 102. In this case, the functions of the diagnostic device 104 may be incorporated in one uninterruptible power supply device 102, or the functions of the diagnostic device 104 may be incorporated in all uninterruptible power supply devices 102, and one uninterruptible power supply device 102 may be operated as a diagnostic device when the system is operated.

Fig. 2 is a structural diagram of the uninterruptible power supply unit 102. The uninterruptible power supply 102 is connected to the power system 101 (see fig. 1) via a power input terminal 201, and ac power from the power system 101 is input to a rectifier 203 via an on-off switch 202. The rectifier 203 converts the ac power into dc power to charge the rechargeable battery 204. Dc power is discharged from the rechargeable battery 204 as necessary, and is converted from dc power to ac power by the inverter 205. The uninterruptible power supply unit 102 is connected to the load unit 103 via a power output terminal 207, and outputs ac power from an inverter 205 to the load unit 103 via a path switching switch 206 (see fig. 1).

The on-off switch 202 is disconnected from the power system 101 as necessary, and the path switching switch 206 switches the supply source of the ac power between the power system 101 and the inverter 205. Further, in the uninterruptible power supply unit 102, as signal terminals, a signal input terminal 208 for receiving a signal from the diagnostic device 104 and a signal output terminal 209 for transmitting a signal to the diagnostic device 104 are provided. The uninterruptible power supply device 102 in fig. 2 is an example of a device, and may be configured by any one of a constant inverter power supply system, a line-alternating system, and a constant commercial power supply system.

Fig. 3 is a structural diagram of the rechargeable battery 204. The rechargeable battery 204 has a plurality of battery cells connected in series to increase the voltage, and if necessary, a plurality of battery cells connected in parallel, and the battery cell group 301 having a high capacity is electrically connected to the outside through the battery connection terminal 306 (parallel connection is not shown). The current flowing into and out of the cell group 301 is measured by a current sensor 303, and a representative temperature is measured from the plurality of cells by a temperature sensor 304. The representative temperature is a temperature value measured at a position where the temperature is highest, a position where the temperature is lowest, a position where an average temperature is obtained, and the like among the plurality of cells. The electric power to be input to or output from the cell group 301 can be measured by multiplying the total value of the voltages of the cells measured by the battery management unit 302 by the current value measured by the current sensor 303.

The rechargeable battery 204 is provided with a battery management unit 302 that manages each battery cell of the battery cell group 301, and a state detection unit 305 that detects the state of the battery cell group 301. The battery management unit 302 has a function of measuring the voltages of the cells of the cell group 301, and a function of equalizing voltage variations when voltage variations occur among the cells. The state detection unit 305 detects the states of the battery cell 301, such as the SOC, the presence or absence of an abnormality, and the capacity value (capacity performance), using the measurement values measured by the battery management unit 302, the current sensor 303, and the temperature sensor 304. The state detection unit 305 detects the state by a command input from the battery signal input terminal 307, and outputs the detection result to the outside from the battery signal output terminal 308.

As such a rechargeable battery 204, a lithium ion battery has begun to spread, and in the uninterruptible power supply unit 102 of the present embodiment, a lithium ion battery is also used as the rechargeable battery 204. As factors of deterioration of the lithium ion battery, there are storage deterioration in which deterioration progresses by storage in a high state of charge, and cycle deterioration in which deterioration progresses according to the frequency of use. Since the uninterruptible power supply unit 102 (see fig. 2) is not used if a failure such as a power failure does not occur, it is a main cause of deterioration to be stored in a lithium ion battery serving as the rechargeable battery 204 of the uninterruptible power supply unit 102. When the rechargeable battery 204 is continuously maintained in the fully charged state without using the uninterruptible power supply unit 102, the internal resistance increases and the full charge capacity decreases.

When the capacity of the rechargeable battery 204 of the uninterruptible power supply unit 102 is degraded, the necessary power may not be supplied to the load unit 103 at the time of failure. The capacity deterioration of the rechargeable battery 204 of the uninterruptible power supply unit 102 needs to be diagnosed periodically, but in order to diagnose the capacity deterioration of the rechargeable battery 204 with high accuracy, the rechargeable battery 204 needs to be actually discharged. Since the total amount of power that can be supplied from the power supply system to the load device 103 is reduced by discharging the rechargeable battery 204, it is necessary to secure extra backup power in order to diagnose capacity deterioration by discharging the rechargeable battery 204.

Therefore, in the uninterruptible power supply unit 102 according to the present embodiment, the rechargeable battery 204 is constantly maintained in a state of charge lower than the fully charged state, focusing on the fact that the capacity deterioration is increased by the fully charged state of the rechargeable battery 204. The reserve deterioration of the rechargeable battery 204 is suppressed, and the remaining power is retained in the charged state of the rechargeable battery 204, and the remaining power in the charged state is used as the backup power. This makes it possible to actually discharge the rechargeable battery 204 and diagnose the capacity deterioration while maintaining the total amount of the stored electric power of the rechargeable battery 204 as the whole of the uninterruptible power supply units 102.

Hereinafter, the capacity diagnosis of the first embodiment will be described in detail. The uninterruptible power supply unit 102 operates in 2 operation modes, i.e., a normal mode for preparing for power outage and power storage and a diagnostic mode for diagnosing capacity deterioration of the rechargeable battery 204. The normal mode is an operation mode in which the rechargeable battery 204 can be charged to the first SOC (first state of charge). In the normal mode, the uninterruptible power supply unit 102 operates to maintain the charge level at the first SOC. The diagnostic mode is an operation mode in which the rechargeable battery 204 can be charged to a second SOC (second state of charge) higher than the first SOC in the normal mode. In the diagnosis mode, the capacity deterioration is diagnosed by performing discharge of the rechargeable battery 204. The SOC indicates the amount of power stored with respect to the full charge of the rechargeable battery 204. The uninterruptible power supply 102 is provided with a control unit (not shown) that collectively controls various processes such as setting of an operation mode and communication control with the diagnostic device 104.

Fig. 4 is a control block diagram of the diagnostic device 104. The diagnostic apparatus 104 is provided with a control unit 401 that controls the respective units of the apparatus collectively. The control unit 401 includes: a target determination unit 402 that determines a diagnostic target from among the uninterruptible power supply units 102 (see fig. 1); and a mode switching unit 403 for switching the operation mode of the uninterruptible power supply unit 102. Further, the diagnostic device 104 is provided with: a charge/discharge control unit 404 that controls charging/discharging of the rechargeable battery 204 (see fig. 2) of the uninterruptible power supply unit 102; and a capacity deterioration diagnosis unit 405 that diagnoses capacity deterioration of the rechargeable battery 204. The target determination unit 402 determines the uninterruptible power supply unit 102, which has elapsed a predetermined time since the last diagnosis time, as the diagnosis target. When there are a plurality of uninterruptible power supply units 102 for which a predetermined time has elapsed, the uninterruptible power supply unit 102 for which the longest time has elapsed since the last diagnosis time is determined as the diagnosis target.

The mode switching unit 403 outputs a transition command to the normal mode or the diagnostic mode to the plurality of uninterruptible power supply units 102, and switches the operation mode of the uninterruptible power supply units 102. When the diagnosis of the capacity deterioration is started, the uninterruptible power supply unit 102 is switched from the normal mode to the diagnosis mode by a transition command to the diagnosis mode, and the rechargeable battery 204 can be charged to the second SOC having the higher charge level. When the diagnosis of the capacity deterioration is completed, the uninterruptible power supply unit 102 is switched from the diagnosis mode to the normal mode by a transition command to the normal mode, and the charge level of the rechargeable battery 204 is suppressed to the first SOC, thereby suppressing the retention deterioration.

The charge/discharge control unit 404 outputs a charge command or a discharge command to the uninterruptible power supply units 102. When the uninterruptible power supply 102 operates in the normal mode, the charge/discharge control unit 404 controls charge/discharge in accordance with a charge command or a discharge command so that each uninterruptible power supply 102 maintains the rechargeable battery 204 at the first SOC. When the uninterruptible power supply 102 operates in the diagnostic mode, the charge/discharge control unit 404 controls the charging command or the discharging command so that the uninterruptible power supply 102 to be diagnosed discharges the rechargeable battery 204 while maintaining the total amount of power of the uninterruptible power supply 102. The timing of the charge command and the discharge command will be described later.

The capacity deterioration diagnosis unit 405 acquires the current amount or the electric power amount at the time of discharge of the rechargeable battery 204 from the state detection unit 305 (see fig. 3) as a capacity value, and diagnoses that the capacity is insufficient when the current amount or the electric power amount is lower than a predetermined threshold value. The state detector 305 measures the current or voltage until the voltage reaches the lower limit voltage by discharging the rechargeable battery 204, and calculates the amount of current or the amount of electric power by integrating the power value obtained by multiplying the current measurement value or the current measurement value by the voltage measurement value. The capacity deterioration diagnosis unit 405 may acquire the discharge time of the rechargeable battery 204 from the state detection unit 305 as a capacity value, and diagnose that the capacity is insufficient when the discharge time is less than a predetermined time. The state detection unit 305 measures a discharge time until the voltage reaches the lower limit voltage by discharging the rechargeable battery 204.

The control unit of the uninterruptible power supply 102 and the control unit 401 of the diagnostic apparatus 104 may be implemented by software using a processor, or may be implemented by a logic circuit (hardware) formed in an integrated circuit or the like. In the case of using a processor, the processor implements various processes by reading out and executing a program stored in a memory. Examples of the processor include a cpu (central Processing unit), an mpu (micro Processing unit), a gpu (graphics Processing unit), and a dsp (digital Signal processor). The memory is composed of one or more recording media such as rom (read Only memory), ram (random Access memory), nvram (non Volatile ram) and the like, depending on the application.

A method of diagnosing the capacity deterioration of the rechargeable battery 204 will be described with reference to fig. 5 and 6. Fig. 5 shows an example of the charging state of the uninterruptible power supply units 102A to 102E in the normal mode. In the normal mode, all of the rechargeable batteries 204 of the uninterruptible power supply units 102A-102E are charged to the first SOC. The first SOC is determined based on a standby time for continuing the operation of the load device 103 at the time of power failure, a required time until the power generator (not shown) is started at the time of power failure, and the like. In the present embodiment, assuming that the first SOC is set to 80%, a remaining capacity of 20% is reserved in the rechargeable battery 204 of each uninterruptible power supply unit 102A to 102E.

Fig. 6 shows an example of the state of charge of the uninterruptible power supply units 102A to 102E in the diagnostic mode. In the diagnosis mode, the rechargeable battery 204 of the uninterruptible power supply units 102B to 102E other than the diagnosis target is charged to a second SOC higher than the first SOC in the normal mode. In the present embodiment, the secondary SOC is assumed to be 100%, and the rechargeable battery 204 of the uninterruptible power supply units 102B to 102E other than the diagnostic object is charged 20% at a time. After the rechargeable battery 204 of the uninterruptible power supply units 102B to 102E is charged to the second SOC, the total amount of stored power can be maintained at the same level as that in the normal mode even if the uninterruptible power supply unit 102A to be diagnosed is discharged to SOC 0%. Therefore, the rechargeable battery 204 of the uninterruptible power supply device 102A can be forcibly discharged to the SOC 0% to diagnose the capacity degradation of the rechargeable battery 204.

The rechargeable battery 204 of the uninterruptible power supply units 102B to 102E outside the discharging object is charged to the second SOC. Therefore, even if the rechargeable battery 204 of the uninterruptible power supply 102A to be diagnosed is forcibly discharged for the purpose of diagnosing capacity deterioration, the amount of stored electricity in the normal mode can be maintained as the total amount of the amount of stored electricity of the plurality of uninterruptible power supply 102A to 102E. Even if a power failure occurs while the uninterruptible power supply 102A is discharging the rechargeable battery 204, a desired power can be supplied to the load device 103. The forced discharge of the uninterruptible power supply 102A is realized by, for example, stopping the operation of the rectifier 203 (see fig. 2) or turning on the on/off switch 202 (see fig. 2) to cut off the supply of electric power from the power system 101.

As described above, the diagnosis of the capacity deterioration of the rechargeable battery 204 is performed based on the amount of current or the amount of electric power when the rechargeable battery 204 is discharged from the first SOC to the SOC 0%, that is, until the voltage reaches the lower limit voltage. The diagnosis of the capacity deterioration of the rechargeable battery 204 may be performed based on a discharge time during which the rechargeable battery 204 is discharged from the first SOC to the SOC 0%, that is, from the time when the voltage reaches the lower limit voltage.

In this way, the diagnostic apparatus 104 causes the uninterruptible power supply apparatuses 102B to 102E other than the object of diagnosis to charge the rechargeable battery 204 to the second SOC, and causes the uninterruptible power supply apparatus 102A to be the object of diagnosis to discharge the rechargeable battery 204. Thus, the entire power storage amount of the power supply system can be maintained by all the rechargeable batteries 204 of the uninterruptible power supply units 102A to 102B, and the uninterruptible power supply unit 102A to be diagnosed can be caused to discharge the rechargeable batteries 204 to diagnose the capacity deterioration with high accuracy.

The diagnostic device 104 sequentially diagnoses the capacity deterioration of the rechargeable batteries of all the uninterruptible power supply devices 102A to 102E by changing the diagnostic target among the uninterruptible power supply devices 102A to 102E. That is, by sequentially changing the uninterruptible power supply unit 102 that is forcibly discharged and charging the secondary battery 204 of the other uninterruptible power supply unit 102 to the second SOC before the forced discharge, it is possible to diagnose the capacity deterioration of the secondary battery 204 of all of the uninterruptible power supply units 102A to 102E with reliability secured.

The capacity deterioration diagnosis process will be described with reference to fig. 7. Fig. 7 is a timing chart of the capacity deterioration diagnosis process. In addition, the diagnosis process of capacity deterioration is performed at regular intervals. First, the diagnostic device 104 periodically acquires the elapsed time from the previous diagnostic process from each uninterruptible power supply 102 (step S01). Next, the diagnostic apparatus 104 (the object determination unit 402) determines the uninterruptible power supply 102 to be diagnosed based on the elapsed time acquired from each uninterruptible power supply 102 (step S02). The elapsed time obtained from the uninterruptible power supply 102 is compared with a predetermined time, and the uninterruptible power supply 102 having an elapsed time longer than the predetermined time is determined as a diagnosis target. When the elapsed time obtained from the uninterruptible power supply units 102 is longer than a predetermined time, the uninterruptible power supply unit 102 with the longest elapsed time is determined as the diagnosis target.

Next, the diagnostic device 104 (mode switching unit 403) issues a transition command from the normal mode to the diagnostic mode to all of the uninterruptible power supply devices 102 (step S03). Each uninterruptible power supply 102 receives the transition command and switches the operation mode from the normal mode to the diagnostic mode (step S04). Next, the diagnostic device 104 (charge/discharge control unit 404) issues a charge command having the second SOC as a command value to the uninterruptible power supply device 102 outside the object to be diagnosed (step S05). The uninterruptible power supply unit 102 outside the diagnosis target receives the charging command, charges the rechargeable battery 204 to the second SOC (step S06), and after the charging of the rechargeable battery 204 is completed, issues a charging completion notification to the diagnosis unit 104 (step S07). Thus, even if the rechargeable battery 204 of the uninterruptible power supply unit 102 to be diagnosed is forcibly discharged, a sufficient amount of power can be reserved for the load unit 103 in the rechargeable battery 204 of the uninterruptible power supply unit 102 other than the object to be diagnosed.

Upon receiving the charge completion notification, the diagnostic device 104 (charge/discharge control unit 404) issues a discharge command for forcibly discharging the rechargeable battery 204 to the uninterruptible power supply device 102 to be diagnosed (step S08). The uninterruptible power supply device 102 to be diagnosed starts forced discharge of the rechargeable battery 204 upon receiving the discharge command (step S09). The operation of the rectifier 203 (see fig. 2) is stopped, the on/off switch 202 is turned off, and the state in which the electric power from the power system 101 is not supplied is set, whereby the rechargeable battery 204 is forcibly discharged. Other discharge methods may be employed as long as the rechargeable battery 204 can be forcibly discharged.

When the uninterruptible power supply unit 102 to be diagnosed starts the forced discharge of the rechargeable battery 204, the capacity value of the rechargeable battery 204 is calculated during the forced discharge (step S10). Until the voltage of the rechargeable battery 204 reaches the lower limit voltage and the discharge is stopped, the state detector 305 measures the current or the power, and calculates the amount of current or the amount of power obtained by integrating the current or the power as the capacity value of the rechargeable battery 204. The state detector 305 may calculate a discharge time from the start of forced discharge until the voltage of the rechargeable battery 204 reaches the lower limit voltage as the capacity value. When the forced discharge of the rechargeable battery 204 is completed, the uninterruptible power supply unit 102 as the diagnosis target issues a discharge completion notification and a capacity value of the rechargeable battery 204 to the diagnosis device 104 (step S11).

The diagnostic device 104 (capacity deterioration diagnostic unit 405) receives the discharge completion notification and the capacity value of the rechargeable battery 204, and diagnoses the capacity shortage of the rechargeable battery 204 based on the capacity value (step S12). When the current amount or the electric power amount is measured as the capacity value, the capacity shortage is diagnosed when the current amount or the electric power amount is lower than a predetermined threshold value. When the discharge time is measured as the capacity value, the discharge time is compared with a predetermined time, and when the discharge time is less than the predetermined time, it is diagnosed that the capacity is insufficient. In addition, in these predetermined threshold values and predetermined time periods, values obtained from past data or the like through experiments, experiences, or theories are used according to whether or not the capacity performance of the rechargeable battery 204 is sufficient each time a desired electric power is supplied to the load device 103.

Here, the diagnostic device 104 diagnoses the capacity shortage of the rechargeable battery 204, but the configuration is not limited thereto. The capacity shortage may be diagnosed by the state detector 305 of the uninterruptible power supply 102 to be diagnosed, and the capacity shortage may be transmitted from the uninterruptible power supply 102 to the diagnostic apparatus 104 by a warning message or the like. The state detector 305 of the uninterruptible power supply 102 calculates the amount of current, the amount of power, the discharge time, and the like, but is not limited to this configuration. The state detector 305 may notify the diagnostic device 104 of the measured value of the current or the electric power of the rechargeable battery 204, and the diagnostic device 104 may calculate the amount of current or the amount of electric power obtained by integrating the measured value of the current or the electric power as the capacity value. The diagnostic device 104 may also issue a discharge command, and the diagnostic device 104 may measure the time until the voltage of the rechargeable battery 204 reaches the lower limit voltage, thereby calculating the discharge time as the capacity value.

Next, after the diagnosis of the capacity deterioration, the diagnostic device 104 (mode switching unit 403) issues a transition command from the diagnostic mode to the normal mode to all the uninterruptible power supply devices 102 (step S13). Each uninterruptible power supply 102 receives the transition command and switches the operation mode from the diagnostic mode to the normal mode (step S14). Next, the diagnostic device 104 (charge/discharge control unit 404) issues a charge command having the first SOC as a command value to the uninterruptible power supply device 102 to be diagnosed (step S15). Upon receiving the charge command, the uninterruptible power supply unit 102 as the diagnosis target charges the rechargeable battery 204 to the first SOC (step S16), and after the charging of the rechargeable battery 204 is completed, the diagnosis unit 104 issues a charge completion notification (step S17).

Next, the diagnostic device 104 (charge/discharge control unit 404) issues a discharge command having the first SOC as a command value to the uninterruptible power supply device 102 outside the object to be diagnosed (step S18). The uninterruptible power supply unit 102 outside the diagnosis target receives the discharge command, discharges the rechargeable battery 204 to the first SOC (step S19), and after the discharge of the rechargeable battery 204 is completed, issues a discharge completion notification to the diagnosis device 104 (step S20). Then, upon receiving the completion notification from all the uninterruptible power supply units 102, the diagnostic device 104 determines that the rechargeable batteries 204 of all the uninterruptible power supply units 102 are restored to the first SOC, and completes the diagnostic process (step S21).

In the above-described diagnostic process, after the non-power-outage power supply apparatus 102 other than the diagnostic object has charged the rechargeable battery 204 to the second SOC and the stored amount is secured, the non-power-outage power supply apparatus 102 of the diagnostic object is caused to forcibly discharge the rechargeable battery 204 to diagnose the capacity degradation, but the configuration is not limited thereto. The uninterruptible power supply unit 102 to be diagnosed may be caused to discharge the rechargeable battery 204 in parallel with the charging of the rechargeable battery 204 by the uninterruptible power supply unit 102 to be diagnosed. In this case, while maintaining the total amount of the stored electric power of the rechargeable batteries 204 of the plurality of uninterruptible power supply units 102 at a predetermined level or more, the uninterruptible power supply unit 102 to be diagnosed discharges the rechargeable batteries 204 to diagnose the capacity deterioration of the rechargeable batteries 204.

Fig. 8 is a time chart of another diagnosis process of capacity deterioration. In addition, the processing of steps S31 to S34 is the same as the processing of steps S01 to S04 of fig. 7, and therefore, the description is omitted. The diagnostic device 104 (charge/discharge control unit 404) issues a charge command to the uninterruptible power supply device 102 outside the diagnostic object and also issues a discharge command to the uninterruptible power supply device 102 of the diagnostic object (step S35). At this time, a charge command having the second SOC as a command value is transmitted to the uninterruptible power supply device 102 outside the object of diagnosis, and a discharge command having a discharge current equal to or less than the total amount of charge current of the uninterruptible power supply device 102 outside the object of diagnosis as a command value is transmitted to the uninterruptible power supply device 102 outside the object of diagnosis. Further, a discharge command having a discharge power equal to or less than the total amount of the charge power of the uninterruptible power supply unit 102 outside the object of diagnosis as a command value may be issued to the uninterruptible power supply unit 102 of the object of diagnosis.

The uninterruptible power supply device 102 outside the diagnosis target receives the charge command to charge the rechargeable battery 204 to the second SOC, and the uninterruptible power supply device 102 outside the diagnosis target receives the discharge command to forcibly discharge the rechargeable battery 204 (step S36). This makes it possible to forcibly discharge the rechargeable battery 204 of the uninterruptible power supply 102 to be diagnosed while maintaining the total amount of the stored electric power of all the uninterruptible power supply 102 at the total amount of the stored electric power in the normal mode or more. When the uninterruptible power supply unit 102 to be diagnosed starts the forced discharge of the rechargeable battery 204, the capacity value of the rechargeable battery 204 is calculated during the forced discharge (step S37).

The uninterruptible power supply device 102 outside the diagnosis target issues a charge completion notification to the diagnosis device 104 after the charge is completed, and the uninterruptible power supply device 102 outside the diagnosis target issues a discharge completion notification and a capacity value to the diagnosis device 104 after the discharge is completed (step S38). Since the charged battery 204 of the uninterruptible power supply 102 to be diagnosed can be forcibly discharged to diagnose capacity deterioration without waiting for the completion of charging of the charged battery 204 of the uninterruptible power supply 102 to the second SOC, the diagnosis time can be shortened. The processing of steps S39 to S48 is the same as the processing of steps S12 to S21 in fig. 7, and therefore, the description thereof is omitted.

As described above, the diagnostic device 104 according to the first embodiment causes the uninterruptible power supply device 102 other than the diagnostic target among the uninterruptible power supply devices 102 to charge the rechargeable battery 204 from the first SOC to the second SOC, and causes the uninterruptible power supply device 102 to be diagnosed to discharge the rechargeable battery 204. This allows the rechargeable battery 204 of the uninterruptible power supply unit 102 to be diagnosed to be discharged while the rechargeable battery 204 of the uninterruptible power supply unit 102 outside the object to be diagnosed is used to secure the backup power. Therefore, the capacity deterioration of the rechargeable battery 204 of the uninterruptible power supply unit 102 to be diagnosed can be diagnosed with high accuracy.

[ second embodiment ]

Next, a power supply system of a second embodiment will be described. The second embodiment is different from the first embodiment in that the rechargeable battery 204 of the uninterruptible power supply unit 102 to be diagnosed is charged and discharged between the first SOC and the second SOC, thereby diagnosing the capacity deterioration of the rechargeable battery 204. Therefore, the same structure as that of the first embodiment will be omitted as much as possible.

Fig. 9 shows an example of the state of charge of the uninterruptible power supply units 102A to 102E in the diagnostic mode according to the second embodiment. In the diagnostic mode, after the rechargeable battery 204 of the uninterruptible power supply devices 102A-102E is charged to a second SOC higher than the first SOC of the normal mode, the rechargeable battery 204 of the uninterruptible power supply devices 102A-102E is discharged from the second SOC to the first SOC. In the second embodiment, similarly to the first embodiment, the first SOC is set to 80%, the second SOC is set to 100%, and the SOC of the rechargeable battery 204 of all the uninterruptible power supply units 102A to 102E is changed by 20% at a time. The amount of current or electric power at the time of discharge is measured, and the capacity value of the rechargeable battery 204 is measured from the amount of current or electric power and the amount of change in SOC. In the present embodiment, since the SOC variation amount is 20%, if the current amount at the time of discharge is 4 times, the capacity value (current amount) of SOC 80%, which is the power storage amount in the normal mode, can be measured. Alternatively, since the SOC variation amount is 20%, if the amount of electric power at the time of discharge is set to 4 times and multiplied by a correction coefficient for correcting the difference between the voltage value from the second SOC to the first SOC and the voltage value from the first SOC to the lower limit SOC, the capacity value (amount of electric power) of SOC 80%, which is the amount of electric power stored in the normal mode, can be measured.

Instead of using the measured value of the amount of current or the amount of electric power generated from the second SOC to the first SOC, the measured value of the amount of current or the amount of electric power charged from the first SOC to the second SOC may be used to measure the capacity value of the rechargeable battery 204. The capacity value of the rechargeable battery 204 may be measured by a discharge time from the second SOC to the first SOC or a charge time from the first SOC to the second SOC. By measuring the capacity value of the rechargeable battery 204 of each uninterruptible power supply unit 102A to 102E in this manner, it is possible to diagnose the capacity deterioration of the rechargeable battery 204 of the uninterruptible power supply units 102A to 102E. In addition, the uninterruptible power supply devices 102A-102E may be diagnosed simultaneously or the uninterruptible power supply devices 102A-102E may be diagnosed individually.

As described above, in the second embodiment, the amount of power stored in each uninterruptible power supply unit 102 can be maintained at the first SOC or more by charging or discharging the rechargeable battery 204 between the first SOC and the second SOC. Therefore, the uninterruptible power supply device 102 to be diagnosed can be actually discharged while the backup power is secured, and the deterioration in the capacity of the rechargeable battery 204 can be diagnosed with high accuracy.

[ third embodiment ]

Next, a power supply system of a third embodiment will be described. The third embodiment is different from the first embodiment in that a power generation facility is connected to a power supply system. Therefore, the same structure as that of the first embodiment will be omitted as much as possible. In addition, although the solar panel is described as an example of the power generation facility, the power generation facility may be any facility provided with a generator such as a wind power generator or a water current generator.

Fig. 10 is a configuration diagram of a power supply system of the third embodiment. The power supply system is connected to a solar panel 501 via a solar power generation PCS502, and is connected to a commercial power supply 504 as a power system. The generated power of the solar panel 501 is supplied to the rechargeable battery 204 (see fig. 2) of the uninterruptible power supply unit 102 or the load device 103 via the solar power PCS 502. Further, the power generation system is provided with a power management device 503 that manages power in the system. The power management device 503 manages the charge per time period of the commercial power supply 504, the power generation state of the solar panel 501, and the power consumption of the load device 103.

In this power supply system, the rechargeable battery 204 of the uninterruptible power supply unit 102 is normally charged with electric power from the solar panel 501 or the commercial power supply 504, and during a power failure, the load unit 103 is supplied with electric power in an amount corresponding to the amount of electric power stored in the rechargeable battery 204 of the uninterruptible power supply unit 102. When diagnosing the capacity of the rechargeable battery 204 of the uninterruptible power supply unit 102, the power management unit 503 controls the timing of issuing a charging command and a discharging command from the diagnostic unit 104 to the uninterruptible power supply unit 102.

The power management device 503 issues a charging instruction from the diagnostic device 104 to the uninterruptible power supply device 102 during a time period when the electricity rate of the commercial power supply 504 is inexpensive. The power management device 503 compares the generated power of the solar panel 501 with the power consumption of the load device 103, and issues a charging command from the diagnostic device 104 to the uninterruptible power supply device 102 when the generated power is excessive. When the electricity rate is low or the generated power is excessive, the uninterruptible power supply unit 102 is caused to charge the rechargeable battery 204, thereby reducing the electricity rate.

The power management device 503 issues a discharge instruction from the diagnostic device 104 to the uninterruptible power supply device 102 during a time period when the electricity rate of the commercial power supply 504 is expensive. The power management device 503 compares the generated power of the solar panel 501 with the power consumption of the load device 103, and issues a discharge command from the diagnostic device 104 to the uninterruptible power supply 102 when the generated power is insufficient. The time zone in which the electricity cost is high or the generated power is insufficient is used for the diagnosis of the capacity deterioration, and the load device 103 is supplied with power by the discharge of the uninterruptible power supply device 102. Therefore, the power purchase from the commercial power supply can be suppressed, and the electric power rate can be reduced.

As described above, in the third embodiment, the rechargeable battery 204 is charged with the electric power from the commercial power supply 504 during a time period when the electric charge is inexpensive. Similarly, when the generated power of the solar panel 501 is excessive, the rechargeable battery 204 is charged with the amount of the generated power. On the other hand, in a time zone where the electricity charge is expensive, in order to suppress the purchase of electricity from commercial power supply 504, the capacity deterioration is diagnosed while supplying power to load device 103 by the discharge of rechargeable battery 204. Similarly, when the generated power of solar panel 501 is insufficient, rechargeable battery 204 is also discharged to suppress the purchase of commercial power. This makes it possible to diagnose the capacity deterioration of the rechargeable battery 204 of the uninterruptible power supply unit 102 while suppressing an increase in the electric power rate.

[ fourth embodiment ]

Next, a power supply system of a fourth embodiment will be described. The fourth embodiment is different from the first embodiment in that another power supply system can be connected to the power supply system. Therefore, the same structure as that of the first embodiment will be omitted as much as possible. Note that, although an electric vehicle is described as an example of another power supply system, the other power supply system may be configured to be capable of supplying electric power to the power supply system of the present embodiment.

Fig. 11 is a configuration diagram of a power supply system of the fourth embodiment. The power supply system is connected to the electric vehicle 601 via a charger 602 as a connector, and is connected to the commercial power supply 504 as a power system. The electric vehicle 601 is provided with a rechargeable battery (not shown). In addition to charging the rechargeable battery of electric vehicle 601, charger 602 can extract electric power from the rechargeable battery of electric vehicle 601 to the power supply system as needed. When the electric vehicle 601 is connected to the charger 602, the power management device 503 is notified of the amount of charge of the rechargeable battery of the electric vehicle 601 from the charger 602, and the power management device 503 supplies the amount of charge of the rechargeable battery of the electric vehicle 601 to control the timing of the capacity diagnosis.

The power management device 503 compares the stored power amount of the rechargeable battery of the electric vehicle 601 with the stored power amount of the rechargeable battery 204 of the uninterruptible power supply device 102 to be diagnosed, and when the stored power amount of the rechargeable battery of the electric vehicle 601 is large, a discharge command is issued from the diagnostic device 104 to the uninterruptible power supply device 102. Even if a power failure occurs while the uninterruptible power supply unit 102 to be diagnosed is discharging the rechargeable battery 204, the amount of stored electricity in the rechargeable battery of the electric vehicle 601 can replace the amount of stored electricity in the uninterruptible power supply unit 102 during discharge, and therefore, a desired amount of electric power can be supplied to the load device 103. In this way, the rechargeable battery 204 of the uninterruptible power supply unit 102 to be diagnosed can be discharged to diagnose capacity deterioration by using the amount of charge of the rechargeable battery of the electric vehicle 601.

As described above, in the fourth embodiment, the stored electric energy of the rechargeable battery of the other power supply system can be used as the backup power. Therefore, the rechargeable battery of the uninterruptible power supply unit can be actually discharged while the backup power is secured, and the capacity deterioration of the rechargeable battery can be diagnosed with high accuracy.

In the above embodiments, the lithium ion battery was described as an example of the secondary battery 204, but the secondary battery may be a lead storage battery, a nickel cadmium storage battery, a nickel hydrogen battery, or a sodium ion battery.

The above-described diagnosis process of the capacity deterioration in the first and second embodiments is an example, and the diagnosis process of the capacity deterioration may be a method of diagnosing the capacity deterioration of the rechargeable battery of the uninterruptible power supply unit using the capacity region between the first state of charge and the second state of charge.

In the first and second embodiments, the first and second SOC are exemplified as the first and second states of charge, but the first and second states of charge may be the first and second amounts of charge. That is, the state of charge may not be the ratio of the amount of stored electricity to the full charge, but the amount of stored electricity may be used.

In the third and fourth embodiments, the functions of the power management device 503 may be provided in the diagnostic device 104, or the functions of the diagnostic device 104 and the power management device 503 may be provided in the uninterruptible power supply 102.

In the fourth embodiment, the charger 602 is exemplified as the connector, but the connector may be any connector that can be connected to the power supply system and another power supply system so as to transmit electric power.

As described above, the power supply system according to the present embodiment includes: a uninterruptible power supply device (102) having a rechargeable battery (204); and a diagnostic device (104) that diagnoses a capacity deterioration of a rechargeable battery (204) of the uninterruptible power supply device (102), wherein the uninterruptible power supply device (102) operates in a normal mode in which the rechargeable battery (204) can be charged to a first state of charge (first SOC) and a diagnostic mode in which the rechargeable battery (204) can be charged to a second state of charge (second SOC) that is higher than the first state of charge (first SOC), and wherein the diagnostic device (104) switches the uninterruptible power supply device (102) from the normal mode to the diagnostic mode, and diagnoses the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply device (102) using a capacity region between the first state of charge (first SOC) and the second state of charge (second SOC).

According to this configuration, by operating the uninterruptible power supply unit (102) in the diagnostic mode, the capacity region between the first state of charge (first SOC) and the second state of charge (second SOC) can be used as the capacity for diagnosing the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply unit (102). Therefore, the rechargeable battery (204) of the uninterruptible power supply device (102) can be actually discharged while the backup power is secured, and the capacity degradation of the rechargeable battery (204) can be diagnosed with high accuracy.

In the power supply system described in the present embodiment, the diagnostic device (104) causes the uninterruptible power supply device (102) to discharge the rechargeable battery (204) when diagnosing capacity deterioration, and diagnoses that the capacity of the rechargeable battery (204) is insufficient when the discharge time until the voltage of the rechargeable battery (204) reaches the lower limit voltage is less than a predetermined time.

According to this configuration, the capacity shortage can be diagnosed from the discharge time of the rechargeable battery (204).

In the power supply system described in the present embodiment, the diagnostic device (104) causes the uninterruptible power supply device (102) to discharge the rechargeable battery (204) when diagnosing capacity deterioration, and diagnoses that the capacity of the rechargeable battery (204) is insufficient when the current amount or the power amount of the rechargeable battery (204) is lower than a predetermined threshold value.

According to this configuration, the capacity shortage can be diagnosed from the amount of current or the amount of power of the rechargeable battery (204).

In the power supply system described in the present embodiment, the uninterruptible power supply device (102) is a plurality of uninterruptible power supply devices (102), the diagnostic device (104) switches the plurality of uninterruptible power supply devices (102) from the normal mode to the diagnostic mode, causes the uninterruptible power supply device (102) other than the diagnostic target of the plurality of uninterruptible power supply devices (102) to charge the rechargeable battery (204) to the second charge state, and causes the uninterruptible power supply device (102) to be diagnosed to discharge the rechargeable battery (204) and diagnose the capacity deterioration of the rechargeable battery (204).

According to this configuration, the rechargeable battery of the uninterruptible power supply unit (102) to be diagnosed can be discharged while the rechargeable battery (204) of the uninterruptible power supply unit (102) outside the object to be diagnosed is used to secure the backup power. Therefore, the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply unit (102) to be diagnosed can be diagnosed with high accuracy.

In the power supply system described in the present embodiment, the diagnostic device (104) diagnoses the capacity deterioration of the rechargeable battery (204) by discharging the rechargeable battery (204) from the uninterruptible power supply device (102) to be diagnosed while maintaining the total amount of the stored electric power of the rechargeable batteries (204) of the uninterruptible power supply devices (102) at a predetermined level or more.

According to this configuration, the rechargeable battery (204) of the uninterruptible power supply unit (102) to be diagnosed can be discharged in parallel with the charging of the uninterruptible power supply unit (102) other than the object to be diagnosed. Therefore, the diagnosis time for the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply device (102) to be diagnosed can be shortened.

In the power supply system described in the present embodiment, the diagnostic device (104) sequentially diagnoses the capacity deterioration of the rechargeable batteries (204) of all the uninterruptible power supply devices (102) by changing the diagnostic target among the uninterruptible power supply devices (102).

According to this configuration, it is possible to diagnose the capacity deterioration of the rechargeable batteries (204) of the uninterruptible power supply units (102) with high accuracy.

In the power supply system described in the present embodiment, the diagnostic device (104) diagnoses the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply device (102) by measuring the capacity value of the rechargeable battery (204) during charging from the first state of charge (first SOC) to the second state of charge (second SOC), or by measuring the capacity value of the rechargeable battery (204) during discharging from the second state of charge (second SOC) to the first state of charge (first SOC).

According to this configuration, the amount of power stored in the uninterruptible power supply unit (102) can be maintained at or above the first state of charge (first SOC) by charging or discharging the rechargeable battery (204) between the first state of charge (first SOC) and the second state of charge (second SOC). Therefore, the rechargeable battery (204) of the uninterruptible power supply unit (102) to be diagnosed can be actually discharged while the backup power is secured, and the capacity degradation of the rechargeable battery (204) can be diagnosed with high accuracy.

In the power supply system described in the present embodiment, the uninterruptible power supply unit (102) charges the rechargeable battery (204) with power from the power generating equipment (the solar panel 501) or the commercial power supply (504), and when power is off, power is supplied from the rechargeable battery (204) to the load device (103), and the diagnostic device (104) causes the uninterruptible power supply unit (102) to charge the rechargeable battery (204) when the generated power of the power generating equipment (the solar panel 501) is surplus or when the electricity rate of the commercial power supply (504) is low.

According to this configuration, the charging battery (204) of the uninterruptible power supply device (102) can be charged when the generated power is surplus or in an inexpensive time zone, thereby reducing the electricity fee.

In the power supply system described in the present embodiment, the uninterruptible power supply device (102) charges the rechargeable battery (204) with power from the power generation equipment (the solar panel 501) or the commercial power supply (504), and when power is off, power is supplied from the rechargeable battery (204) to the load device (103), and the diagnostic device (104) causes the uninterruptible power supply device (102) to discharge the rechargeable battery (204) to diagnose capacity deterioration when the generated power of the power generation equipment (the solar panel 501) is insufficient or when the electricity rate of the commercial power supply (504) is high.

According to this configuration, when the generated power is insufficient or the electricity rate is expensive, the time period is used for diagnosing capacity deterioration, so that the electricity purchase from the commercial power supply (504) can be suppressed and the electricity rate can be reduced.

In the power supply system according to the present embodiment, the rechargeable battery (204) is a lithium ion battery.

According to this configuration, the lithium ion battery is accelerated in deterioration when the amount of stored power is high, but since the uninterruptible power supply unit (102) operates in the normal mode in the first state of charge (first SOC) that is lower than the second state of charge (second SOC), deterioration of the lithium ion battery can be suppressed.

Another power supply system described in this embodiment includes: a uninterruptible power supply device (102) having a rechargeable battery (204); a diagnostic device (104) that diagnoses a capacity degradation of a rechargeable battery (204) of the uninterruptible power supply device (102); and a connector (charger 602) that is connectable to another power supply system (electric vehicle 601) having a rechargeable battery, wherein when the connector (charger 602) is connected to the other power supply system (electric vehicle 601), the diagnostic device (104) causes the uninterruptible power supply device (102) to discharge the rechargeable battery (204) and diagnoses the capacity degradation of the rechargeable battery (204) when the charge capacity of the rechargeable battery of the other power supply system (electric vehicle 601) is equal to or greater than the charge capacity of the rechargeable battery (204) of the uninterruptible power supply device (102).

With this configuration, the amount of electricity stored in the rechargeable battery of the other power supply system (electric vehicle 601) can be used as the backup power. Therefore, the rechargeable battery (204) of the uninterruptible power supply device (102) can be actually discharged while the backup power is secured, and the capacity degradation of the rechargeable battery (204) can be diagnosed with high accuracy.

The diagnostic device (104) according to the present embodiment is a diagnostic device (104) that diagnoses capacity deterioration of a rechargeable battery (204) of a uninterruptible power supply device (102) having the rechargeable battery (204), and diagnoses the capacity deterioration of the rechargeable battery (204) of the uninterruptible power supply device (102) using a capacity region between a first state of charge (first SOC) and a second state of charge (second SOC) in which the uninterruptible power supply device (102) is switched from a normal mode in which the rechargeable battery (204) can be charged to the first state of charge (first SOC) to a diagnostic mode in which the rechargeable battery (204) can be charged to the second state of charge (second SOC) higher than the first state of charge (first SOC).

The uninterruptible power supply device (102) according to the present embodiment is an uninterruptible power supply device (102) having a rechargeable battery (204), and is operable in a normal mode in which the rechargeable battery (204) can be charged to a first state of charge (first SOC) and a diagnostic mode in which the rechargeable battery (204) can be charged to a second state of charge (second SOC) that is higher than the first state of charge (first SOC), and in the diagnostic mode, the capacity deterioration of the rechargeable battery (204) can be diagnosed using a capacity region between the first state of charge (first SOC) and the second state of charge (second SOC).

The embodiments of the present invention have been described in detail, but the present invention is not limited to the embodiments, and various design changes can be made without departing from the spirit of the present invention described in the claims. For example, the embodiments are described in detail to explain the present invention in a manner easy to understand, and are not necessarily limited to having all the structures described. Further, a part of the structure of one embodiment may be replaced with the structure of another embodiment, or the structure of another embodiment may be added to the structure of one embodiment. Further, a part of the configuration of each embodiment can be added, deleted, or replaced with another configuration.

Description of the reference numerals

102 uninterrupted power supply device

104 diagnostic device

204 rechargeable battery

501 sunlight panel (generating equipment)

504 commercial power supply

601 electric car (other power supply system)

602 charger (connector)

Claims

1. A power supply system having: a uninterruptible power supply device having a rechargeable battery; and a diagnostic device for diagnosing capacity deterioration of a rechargeable battery of the uninterruptible power supply device,

the uninterruptible power supply device is operated in a normal mode in which the rechargeable battery can be charged to a first state of charge and a diagnostic mode in which the rechargeable battery can be charged to a second state of charge higher than the first state of charge,

the diagnostic device switches the uninterruptible power supply device from the normal mode to the diagnostic mode, and diagnoses a capacity deterioration of a rechargeable battery of the uninterruptible power supply device using a capacity region between the first state of charge and the second state of charge.

2. The power supply system according to claim 1,

the diagnostic device causes the uninterruptible power supply device to discharge the rechargeable battery at the time of diagnosing the capacity deterioration, and diagnoses that the capacity of the rechargeable battery is insufficient when a discharge time until the voltage of the rechargeable battery reaches a lower limit voltage is less than a predetermined time.

3. The power supply system according to claim 1,

the diagnostic device causes the uninterruptible power supply device to discharge a rechargeable battery at the time of diagnosing capacity deterioration, and diagnoses that the capacity of the rechargeable battery is insufficient when the amount of current or the amount of power of the rechargeable battery is lower than a predetermined threshold.

4. The power supply system according to claim 1,

the uninterruptible power supply devices are a plurality of uninterruptible power supply devices,

the diagnostic device switches the plurality of uninterruptible power supply devices from the normal mode to the diagnostic mode, causes an uninterruptible power supply device other than the diagnostic object among the plurality of uninterruptible power supply devices to charge the rechargeable battery to the second charge state, and causes the uninterruptible power supply device to be diagnosed to discharge the rechargeable battery to diagnose the capacity degradation of the rechargeable battery.

5. The power supply system according to claim 4,

the diagnostic device causes the uninterruptible power supply device to be diagnosed to discharge the rechargeable battery while maintaining the total amount of the stored electric energy of the rechargeable batteries of the uninterruptible power supply devices at a predetermined level or more, thereby diagnosing the capacity degradation of the rechargeable battery.

6. The power supply system according to claim 4,

the diagnostic device sequentially diagnoses capacity deterioration of the rechargeable batteries of all the uninterruptible power supply devices by changing a diagnostic object among the uninterruptible power supply devices.

7. The power supply system according to claim 1,

the diagnostic device diagnoses capacity deterioration of a rechargeable battery of the uninterruptible power supply device by measuring a capacity value of the rechargeable battery during charging from the first state of charge to the second state of charge or measuring a capacity value of the rechargeable battery during discharging from the second state of charge to the first state of charge.

8. The power supply system according to claim 1,

the uninterruptible power supply device charges a rechargeable battery with power from a power generating facility or a commercial power supply, supplies power from the rechargeable battery to a load device at the time of power failure,

the diagnostic device causes the uninterruptible power supply device to charge the rechargeable battery when the generated power of the power generation equipment is surplus or when the electricity rate of the commercial power supply is cheap.

9. The power supply system according to claim 1,

the diagnostic device causes the uninterruptible power supply device to discharge the rechargeable battery to diagnose the capacity deterioration when the generated power of the power generation equipment is insufficient or during a time period in which the electricity rate of the commercial power supply is expensive.

10. The power supply system according to any one of claims 1 to 9,

the rechargeable battery is a lithium ion battery.

11. A power supply system having: a uninterruptible power supply device having a rechargeable battery; a diagnostic device that diagnoses capacity deterioration of a rechargeable battery of the uninterruptible power supply device; and a connector capable of connecting with other power supply system having a rechargeable battery, characterized in that,

when the other power supply system is connected to the connector, the diagnostic device causes the uninterruptible power supply device to discharge the rechargeable battery to diagnose the capacity degradation of the rechargeable battery when the charge capacity of the rechargeable battery of the other power supply system is equal to or greater than the charge capacity of the rechargeable battery of the uninterruptible power supply device.

12. A diagnostic device for diagnosing capacity deterioration of a rechargeable battery of a uninterruptible power supply device having the rechargeable battery,

switching the uninterruptible power supply device from a normal mode in which the rechargeable battery can be charged to a first state of charge to a diagnostic mode in which the rechargeable battery can be charged to a second state of charge higher than the first state of charge,

diagnosing capacity deterioration of a rechargeable battery of the uninterruptible power supply device using a capacity region between the first state of charge and the second state of charge.

13. A non-power-off power supply device with a rechargeable battery is characterized in that,

the system is operated in a normal mode in which the secondary battery can be charged to a first state of charge and a diagnostic mode in which the secondary battery can be charged to a second state of charge higher than the first state of charge,

in the diagnosis mode, the capacity deterioration of the rechargeable battery can be diagnosed using a capacity region between the first state of charge and the second state of charge.