JP2009128194A - Storage battery lifetime degradation determining device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage battery lifetime degradation determining method and a device for continuously and simply determining the degradation of storage battery lifetime, such as secondary batteries, during operation in a single-phase electric power storage PCS, in a single-phase power supply. <P>SOLUTION: The life degradation determining device 200 is electrically connected between a smoothing capacitor C and a reactor Ldc and detects the current in a charging current detection means 201. From the current detection value detected by the charging current detection means 201, the ripple component and the DC component are extracted by a ripple component extraction means 202 and an average value calculation part 203, and the pulsation ratio is calculated by a divider 204 and stored in a storage means 204. A pulsation ratio internal resistance database, in which variation of the pulsation ratio to the variation of internal resistance measured in advance is recorded, is stored in a storage means 205. A lifetime degradation determination means 206 determines the internal resistance, by comparing the pulsation ratio data from the storage means 205 with the pulsation ratio-internal resistance database to determine the degradation of the lifetime. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a storage battery life deterioration determination apparatus and method, and more particularly, to a storage battery life deterioration determination apparatus and method for determining life deterioration of a storage battery such as a secondary battery in a single-phase power storage AC / DC converter in a single-phase power source. About.

  When operating a storage battery system, in order to operate the system normally, it is necessary to periodically replace a storage battery whose life is deteriorated by repeated charging and discharging. However, since the degree of life deterioration of each storage battery varies depending on the usage status, if the batteries that have passed for a certain period of time are replaced uniformly, it will be replaced with a normal one, which is very uneconomical. Therefore, various methods for determining the life deterioration degree of the storage battery have been proposed.

  When a storage battery such as a secondary battery deteriorates its life due to repeated charge and discharge, the internal resistance increases. Therefore, a method is known in which a ripple current is passed through the storage battery to determine the internal resistance from the ripple voltage generated at both ends of the storage battery to determine the life deterioration. (See Patent Document 1). In addition, a method has been proposed in which the storage battery voltage, charge / discharge current, internal temperature, internal impedance, specific gravity, and other values are measured at regular intervals to find out what has a correlation with life deterioration and determine the remaining life of the storage battery. (Patent Document 2).

JP 2002-101571 A JP 2006-524332 A

  However, in order to determine the life deterioration, there has been a problem that the configuration is complicated because a calculation means for calculating an internal resistance or an internal impedance using these after measuring a ripple current and a ripple voltage is required.

  The present invention has been made in view of such a problem, and an object thereof is to provide a storage battery such as a secondary battery in a single-phase power storage AC / DC converter (PCS: Power Conversion System) in a single-phase power source. Provides a storage battery life deterioration determination device and method for calculating the ratio of ripple amplitude to the average value of the flowing current (DC component) (hereinafter referred to as “pulsation rate”) and determining life deterioration continuously and simply during operation. There is to do.

  In order to achieve such an object, the invention described in claim 1 is a storage battery life deterioration determination device for determining an internal resistance of a storage battery included in a single-phase power storage AC / DC converter, and a current flowing into the storage battery. Current detecting means for detecting the pulsation rate, a pulsation rate calculating means for separating the current value detected by the current detecting means into a ripple component and a DC component, and calculating a pulsation rate that is a ratio to the DC component of the ripple, and the pulsation And a life deterioration judging means for judging the life deterioration of the storage battery based on whether or not the pulsation rate calculated by the rate calculating means is equal to or less than a preset threshold value.

  The invention according to claim 2 is a storage battery life deterioration determination device for determining an internal resistance of a storage battery included in a single-phase power storage AC / DC converter, wherein the current detection means detects a current flowing into the storage battery, and the current A pulsation rate calculating means for calculating a pulsation rate which is a ratio of the ripple relative to the DC component with respect to the current value detected by the detection means, and a pulsation rate-internal resistance correspondence data relating the pulsation rate and the internal resistance of the storage battery Life deterioration determination for determining the internal resistance of the storage battery by comparing the stored storage means, the pulsation rate-internal resistance correspondence data read from the storage means, and the pulsation rate calculated by the pulsation rate calculating means And a storage battery life deterioration judging device.

  Invention of Claim 3 is a storage battery lifetime deterioration determination system, Comprising: The single phase electric power storage AC / DC converter which has the smoothing circuit which does not contain a reactor on a storage battery and DC side, and the electric current which flows into the said storage battery are detected A current detecting means; a pulsation rate calculating means for calculating a pulsation rate which is a ratio of a DC component of a ripple with respect to a current value detected by the current detecting means; and a pulsation relating the pulsation rate and the internal resistance of the storage battery The storage means storing rate-internal resistance correspondence data, the pulsation rate-internal resistance correspondence data read from the storage means, and the pulsation rate calculated by the pulsation rate calculation means are collated with each other. It is characterized by comprising life deterioration judging means for judging resistance.

  Invention of Claim 4 is a storage battery lifetime deterioration determination system, Comprising: It has a single phase electric power storage conversion apparatus which has a smoothing circuit which does not contain a reactor in several storage batteries and several direct current | flow side, These several single phase electric power A single-phase power storage AC / DC converter in which storage converters are connected in series, current detection means for selectively detecting the current flowing into each storage battery, and a ripple component for the current value detected by the current detection means A pulsation rate calculating means for calculating a pulsation rate that is a ratio with respect to a direct current component; a storage means that stores pulsation rate-internal resistance correspondence data that associates the pulsation rate with the internal resistance of the storage battery; and reading from the storage means And a life deterioration judging means for judging the internal resistance of the storage battery by comparing the pulsation rate-internal resistance correspondence data with the pulsation rate calculated by the pulsation rate calculating means. To.

  The invention according to claim 5 is a storage battery life deterioration determination method for determining an internal resistance of a storage battery included in a single-phase power storage AC / DC converter, wherein the current detection step detects a current flowing into the storage battery, and the current A pulsation rate calculating step for separating a current value detected by the detecting means into a ripple component and a DC component, and calculating a pulsation rate that is a ratio of the ripple to the DC component, and the pulsation rate calculated in the pulsation rate calculating step Is a life deterioration determination step of determining the life deterioration of the storage battery depending on whether or not the value is equal to or less than a preset threshold value.

  The invention according to claim 6 is a storage battery life deterioration determination method for determining an internal resistance of a storage battery included in a single-phase power storage AC / DC converter, a current detection step for detecting a current flowing into the storage battery, and the current The current value detected by the detection means is separated into a ripple component and a DC component, and a pulsation factor calculation step for calculating a pulsation factor that is a ratio of the ripple component to the DC component is associated with the pulsation factor and the internal resistance of the storage battery. The internal resistance of the storage battery is determined by comparing the pulsation rate-internal resistance correspondence data read from the storage means storing the pulsation rate-internal resistance correspondence data with the pulsation rate calculated by the pulsation rate calculating means. And a life deterioration judging step.

  According to the present invention, in a single-phase power storage PCS in a single-phase power supply, it is possible to easily and easily determine the life deterioration of a storage battery such as a secondary battery during operation.

  In the present invention, attention is paid to the current flowing through the storage battery in the single-phase power storage PCS in the single-phase power source. When the internal resistance of the battery increases due to the deterioration of the lifetime, the ratio of the ripple current flowing through the DC side capacitor increases, and the ripple current flowing toward the storage battery decreases. On the other hand, since the direct current does not flow to the capacitor, the direct current flowing to the storage battery side is not affected by the change in internal resistance.

  Thus, by paying attention only to the change in the ratio of the ripple current to the direct current flowing through the storage battery, the life deterioration degree of the battery can be easily determined without calculating the internal resistance from the ripple voltage and the ripple current.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a main circuit configuration example of the single-phase power storage PCS. The current Idco flowing from the PCS 102 includes a ripple of a frequency twice the power supply frequency by single-phase full-wave rectification and a harmonic ripple by switching. At both ends of the smoothing capacitor C, a voltage ripple having a frequency twice as large as the power supply frequency is generated due to this current ripple, and as a result, a ripple corresponding to twice the power supply frequency is generated in the current flowing into the storage battery 103. Become.

  FIG. 2 shows changes in the current waveform when the internal resistance ri changes in the configuration of the single-phase power storage PCS circuit 100. It can be seen that the ripple current amplitude decreases as the internal resistance ri increases. From this result, the ratio of ripple amplitude to the average value (DC component) of the current flowing through the storage battery 103, that is, the pulsation rate, is calculated and arranged in relation to the internal resistance as shown in FIG. That is, it can be seen that the pulsation rate decreases as the battery life deteriorates.

  FIG. 4 shows the relationship between the internal resistance and the pulsation rate at different currents during charging and discharging. From this relationship, the relationship between the internal resistance and the pulsation rate is constant regardless of the charging current during charging, and substantially matches the pulsation rate during charging except when the internal resistance becomes extremely large during discharging. .

  Therefore, by measuring the pulsation rate of the current flowing through the storage battery and using the relationship between the pulsation rate and the change in internal resistance, it is possible to determine the change in internal resistance, that is, the degree of battery life deterioration. The present invention provides a method for measuring and recording the pulsation rate of a current flowing in a storage battery on the DC side of a single-phase power storage PCS in a single-phase power source, and determining the degree of life deterioration based on the change.

(Embodiment 1)
FIG. 5A shows the main circuit configuration of the single-phase power storage PCS, and FIG. 5B shows the configuration of the lifetime deterioration determination apparatus according to the first embodiment of the present invention. According to this method, the life deterioration of a storage battery such as a secondary battery can be easily and continuously determined during operation.

  Single-phase AC power supply 101 supplies AC power to PCS 102 via reactor L, and converts AC power into DC power by performing single-phase full-wave rectification in PCS 102. A storage battery 103 having an electromotive force Ei and an internal resistance ri is connected to the DC side of the PCS 102 via a smoothing capacitor C and a reactor Ldc for ripple current generated during AC / DC conversion.

  The lifetime deterioration determination device 200 is electrically connected between the smoothing capacitor C and the reactor Ldc, and the charge current detection means 201 detects the current. From the detected current value detected by the charging current detection means 201, the ripple extraction means 202 and the average value calculation unit 203 extract the ripple and the DC component, and the divider 204 calculates the ratio of the ripple to the DC component, that is, the pulsation rate. Calculate and store in the storage means 204. In addition to the pulsation rate calculated from the detected current, the storage unit 205 stores a pulsation rate-internal resistance database that records changes in the pulsation rate with respect to changes in internal resistance measured in advance. 206 can collate the pulsation rate data with the pulsation rate-internal resistance database from the storage unit 205 to determine the internal resistance. The determination result of the life deterioration determination unit 206 can be displayed by the determination result display unit 207.

  As a simpler method for determining the life deterioration of the storage battery 103, there is a method that does not use the pulsation rate-internal resistance database of the storage unit 205. In this method, the life deterioration determination device 206 can determine the life deterioration from only the pulsation rate by determining whether or not the pulsation rate is below a preset threshold value.

(Embodiment 2)
In order to protect the storage battery 103, it is necessary to reduce the ripple voltage and the ripple current applied to the storage battery 103. Therefore, a smoothing capacitor and a reactor for removing ripples are generally installed on the DC side of the PCS 102. Further, when the power supply voltage is as low as 100 V or less, a large-capacity capacitor can be used relatively easily, so that the smoothing capacitor alone may be configured as shown in FIG. In this case, the storage battery life deterioration determination device 200 according to the first embodiment is connected between the capacitor C and the storage battery 103 so as to detect a ripple current flowing into the storage battery 103.

  FIG. 7 shows changes in pulsation rate with respect to changes in internal resistance when the reactor is installed in the smoothing circuit for ripple removal and when it is not installed. When the reactor is present, the change in the pulsation rate with respect to the change in the internal resistance is small compared to the case without the reactor. Particularly, when the internal resistance is small, the change in the pulsation rate with respect to the change in the internal resistance is very small. . When the reactor is provided in this manner, the ripple current suppressing effect by the reactor is increased, and therefore the influence of the internal resistance on the ripple change is relatively reduced. Therefore, when the storage battery life deterioration determination device 200 of the first embodiment is used without installing a reactor on the DC side of the PCS 102, the life deterioration determination accuracy based on the pulsation rate of the storage battery life deterioration determination device 200 can be improved.

  In this embodiment, the battery capacity deterioration that improves the accuracy of the storage battery life deterioration determination device that performs the life deterioration determination of the storage battery based on the pulsation rate by reducing the reactor capacity on the DC side of the PCS 102 or without the reactor. A determination system is provided.

(Embodiment 3)
When the system AC power supply is a single-phase 200V, the DC side voltage is 320V or more. Therefore, in practice, a large-capacity capacitor cannot be used due to the limitation of the smoothing capacitor capacity. Therefore, a smoothing circuit combining a capacitor and a reactor. It is necessary to form Therefore, for the reasons described above, the life deterioration determination accuracy is reduced due to the reactor installation.

  FIG. 8A shows the configuration of a storage battery life deterioration determination system that employs the low-voltage battery multiplexed single-phase power storage PCS system according to the third embodiment of the present invention. With respect to the configuration of the storage battery life deterioration determination system according to the first embodiment shown in FIG. 8B, the PCS 102-1 to 102-n, the smoothing capacitors C-1 to Cn, and the storage batteries 103-1 to 103-n. Are connected in series (n: natural number of 2 or more). As a result, the applied voltage of the DC side capacitor is reduced to a voltage at which a general-purpose capacitor can be used, and a DC side reactor is not required.

  Further, the battery life determination device 200 is connected between the storage batteries 103-1 to 103-n and the capacitors C-1 to C-n via the switch 301, and flows into the storage batteries 103-1 to 103-n. The current can be detected.

  As described above, the present embodiment increases the sensitivity of the change in the pulsation rate with respect to the change in the internal resistance, and multiplexes the low-voltage battery to improve the accuracy of the storage battery life deterioration determination device that performs the life deterioration determination of the storage battery due to the change in the pulsation rate. A single-phase power storage PCS type battery life deterioration determination system is provided.

It is a figure which shows the example of a main circuit structure of single phase PCS. 6 is a diagram showing a change in current waveform when an internal resistance ri is changed in the configuration of the single-phase PCS circuit 100. FIG. It is a figure which shows the relationship between a pulsation rate and internal resistance. It is a figure which shows the relationship between internal resistance and a pulsation rate in the state from which each has a different electric current at the time of charge and discharge. (A) is a figure which shows the main circuit structure of single phase PCS, (b) is a figure which shows the structure of the lifetime deterioration determination apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the main circuit structure of the single phase PCS which does not have a reactor on the direct current | flow side. It is a figure which shows the change of the pulsation rate with respect to the change of internal resistance in the case where a reactor is installed in the smoothing circuit for ripple removal, and the case where it does not install. (A) is a figure which shows the storage battery lifetime deterioration determination system which employ | adopted the low voltage battery multiplexing inverter system which concerns on this Embodiment 3 of this invention, (b) is a storage battery lifetime deterioration determination system which concerns on Embodiment 1. FIG. FIG.

Explanation of symbols

100 single-phase PCS circuit 101 AC single-phase power supply 102 PCS
DESCRIPTION OF SYMBOLS 103 Storage battery 200 Storage battery life deterioration determination apparatus 201 Charging current detection means 202 Ripple extraction means 203 Average value calculation means 204 Divider 205 Storage means 206 Life deterioration determination means 207 Determination result display means

Claims (6)

A storage battery life deterioration determination device that determines the internal resistance of a storage battery that the single-phase power storage AC / DC converter has,
Current detecting means for detecting current flowing into the storage battery;
A pulsation rate calculating unit that separates the current value detected by the current detection unit into a ripple component and a DC component, and calculates a pulsation rate that is a ratio to the DC component of the ripple;
The battery life deterioration comprising: a life deterioration determination means for determining the life deterioration of the storage battery based on whether or not the pulsation rate calculated by the pulsation rate calculating means is equal to or less than a preset threshold value. Judgment device. A storage battery life deterioration determination device that determines the internal resistance of a storage battery that the single-phase power storage AC / DC converter has,
Current detecting means for detecting current flowing into the storage battery;
A pulsation rate calculating unit that calculates a pulsation rate that is a ratio of the ripple relative to the DC component with respect to the current value detected by the current detection unit;
Storage means for storing pulsation rate-internal resistance correspondence data in which the pulsation rate and the internal resistance of the storage battery are related;
Life deterioration determining means for determining the internal resistance of the storage battery by comparing the pulsation rate-internal resistance correspondence data read from the storage means with the pulsation rate calculated by the pulsation rate calculating means. A storage battery life deterioration judging device. A single-phase power storage AC / DC converter having a storage circuit and a smoothing circuit not including a reactor on the DC side;
Current detecting means for detecting current flowing into the storage battery;
A pulsation rate calculating unit that calculates a pulsation rate that is a ratio of the ripple relative to the DC component with respect to the current value detected by the current detection unit;
Storage means for storing pulsation rate-internal resistance correspondence data in which the pulsation rate and the internal resistance of the storage battery are related;
Life deterioration determining means for determining the internal resistance of the storage battery by comparing the pulsation rate-internal resistance correspondence data read from the storage means with the pulsation rate calculated by the pulsation rate calculating means. A storage battery life deterioration judging system. A single-phase power storage AC / DC converter having a storage battery and a single-phase power storage converter having a smoothing circuit that does not include a reactor on the DC side, and the plurality of single-phase power storage converters connected in series;
Current detecting means for selectively detecting the current flowing into each of the storage batteries;
A pulsation rate calculating unit that calculates a pulsation rate that is a ratio of the ripple relative to the DC component with respect to the current value detected by the current detection unit;
Storage means for storing pulsation rate-internal resistance correspondence data in which the pulsation rate and the internal resistance of the storage battery are related;
Life deterioration determining means for determining the internal resistance of the storage battery by comparing the pulsation rate-internal resistance correspondence data read from the storage means with the pulsation rate calculated by the pulsation rate calculating means. A storage battery life deterioration judging system. A storage battery life deterioration determination method for determining the internal resistance of a storage battery that a single-phase power storage AC / DC converter has,
A current detection step for detecting a current flowing into the storage battery;
A pulsation rate calculating step of separating a current value detected by the current detection means into a ripple component and a DC component, and calculating a pulsation rate that is a ratio to the DC component of the ripple;
A battery life deterioration determination step, comprising: a life deterioration determination step of determining a life deterioration of the storage battery based on whether or not the pulsation rate calculated in the pulsation rate calculation step is equal to or less than a preset threshold value. Method. A storage battery life deterioration determination method for determining the internal resistance of a storage battery that a single-phase power storage AC / DC converter has,
A current detection step for detecting a current flowing into the storage battery;
A pulsation rate calculating step of separating a current value detected by the current detection means into a ripple component and a DC component, and calculating a pulsation rate that is a ratio to the DC component of the ripple;
The pulsation rate-internal resistance correspondence data read from the storage means storing the pulsation rate-internal resistance correspondence data in which the pulsation rate is related to the internal resistance of the storage battery, and the pulsation rate calculated by the pulsation rate calculating means And a life deterioration determination step of determining the internal resistance of the storage battery by comparing the above and the storage battery life deterioration determination method.

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