Parameter measuring device and parameter measuring method for power storage device

Abstract

To provide a parameter measuring device capable of enhancing measuring accuracy of a parameter obtained by a second detection mechanism.SOLUTION: A parameter measuring device for a power storage device 200 according to the present invention comprises: a first detection mechanism 10 for obtaining a predetermined parameter of a power storage device 200 at a predetermined first period; a second detection mechanism 20 for obtaining the parameter of the power storage device 200 at a predetermined second period longer than the first period; and a control unit 50 connected to the first detection mechanism 10 and the second detection mechanism 20. The control unit 50 comprises: a correction value calculation unit 54 for correcting an obtained value Vb obtained by the second detection mechanism 20 by predetermined processing to calculate a correction value Vc; and a correction value output unit 55 for outputting the correction value to the outside as an output value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a parameter measuring device and a parameter measuring method for an energy storage device. [Background technology]

[0002] Conventionally, power storage devices have been widely used as power sources for driving vehicles, etc. In power storage devices, various parameters (e.g., voltage, current, temperature, state of charge (SOC), etc.) are generally measured by a detection mechanism. The parameters measured by the detection mechanism are monitored to see whether they are within a normal range, and are used for various controls.

[0003] In this regard, for example, Patent Document 1 discloses a power supply device for a vehicle, which includes a power storage device for vehicle running, a voltage detection mechanism for detecting the voltage of the power storage device for vehicle running, the voltage detection mechanism being a redundant configuration in which a high-precision (first) voltage detection mechanism and a simple (second) voltage detection mechanism are connected in parallel, and a failure determination unit for detecting a failure of the first voltage detection mechanism. Patent Document 1 describes that when a failure of the first voltage detection mechanism is detected by the failure determination unit, the voltage of the power storage device is obtained by the second voltage detection mechanism to run the vehicle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-92656 A Summary of the Invention [Problem to be solved by the invention]

[0005] The parameters of the power storage device, particularly electrochemical parameters such as voltage, current, and SOC, fluctuate minutely in a short period of time and have large variations. However, as described in Patent Document 1, for example, in a redundant configuration, the sampling period of the first detection mechanism is shortened (parameters are acquired at short periods), while the sampling period of the second detection mechanism is often set relatively long. As a result, there is a problem that the measurement accuracy of the parameters acquired by the second detection mechanism is relatively low.

[0006] The present invention has been made in consideration of the above circumstances, and its main object is to provide a new parameter measurement device and parameter measurement method for an energy storage device that can improve the measurement accuracy of parameters obtained by the second detection mechanism. [Means for solving the problem]

[0007] The present invention provides a parameter measurement device for an energy storage device, comprising: a first detection mechanism connected to the energy storage device and acquiring a predetermined parameter of the energy storage device in a predetermined first period; a second detection mechanism connected in parallel to the first detection mechanism to the energy storage device and acquiring the parameter of the energy storage device in a predetermined second period longer than the first period; and a control unit connected to the first detection mechanism and the second detection mechanism, wherein the control unit comprises a correction value calculation unit that corrects the acquired value acquired by the second detection mechanism through predetermined processing to calculate a correction value, and a correction value output unit that outputs the correction value to the outside as an output value.

[0008] The present invention also provides a method for measuring a parameter using a parameter measurement device for an energy storage device, the parameter measurement device including a first detection mechanism connected to the energy storage device and acquiring a predetermined parameter of the energy storage device in a predetermined first period, and a second detection mechanism connected in parallel to the first detection mechanism to the energy storage device and acquiring the parameter of the energy storage device in a predetermined second period that is longer than the first period, the parameter measurement method including a correction value calculation step of correcting the acquired value acquired by the second detection mechanism through predetermined processing to calculate a correction value, and a correction value output step of outputting the correction value to the outside as an output value.

[0009] According to the above-mentioned parameter measurement device and parameter measurement method, when a second detection mechanism having a longer sampling period than the first detection mechanism is used, the measurement accuracy of the parameter acquired by the second detection mechanism can be made close to the measurement accuracy of the parameter acquired by the first detection mechanism, thereby improving the accuracy of the output value output to the outside. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic block diagram of a parameter measuring device according to an embodiment. [Diagram 2] FIG. 2 is a flowchart showing an example of a parameter measurement method. [Diagram 3] FIG. 3 is a circuit diagram of a 4-taps-FIR filter. [Figure 4] FIG. 4(A) is a graph showing the variation in the acquired value Vb (for three cells) acquired by the second detection mechanism, and FIG. 4(B) is a graph showing the variation in the corrected value Vc obtained by correcting the acquired value Vb in FIG. 4(A) by the correction value calculation unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, with reference to the drawings, preferred embodiments of the technology disclosed herein will be described. In addition, matters other than those specifically mentioned in this specification and necessary for carrying out the present invention can be understood as design matters of a person skilled in the art based on the prior art in the field. The present invention can be carried out based on the contents disclosed in this specification and the technical common sense in the field. In addition, each drawing is drawn typically and does not necessarily reflect the actual product. In the following, the same reference numerals are given to components and parts that perform the same function, and duplicated explanations are omitted or simplified as appropriate.

[0012] [Parameter measuring device 100] FIG. 1 is a schematic block diagram of a parameter measurement device 100 according to an embodiment. As shown in FIG. 1, the parameter measurement device 100 is connected to a power storage device 200 for use. The power storage device 200 may be a single cell or a battery module including a plurality of single cells. In the battery module, the plurality of single cells may be connected in series. The configuration of the single cell may be the same as that of a conventional device and is not limited in any way. The outer shape of the single cell may be any shape, such as a rectangular parallelepiped (corneral), cylindrical, or pouch-shaped. The single cell is a storage battery, for example, a lithium-ion battery. In this specification, the term "storage battery" refers to a general term for a power storage device that can be repeatedly charged and discharged, and is a concept that includes secondary batteries (chemical batteries) such as lithium-ion secondary batteries and nickel-metal hydride batteries, and capacitors (physical batteries) such as lithium-ion capacitors and electric double-layer capacitors.

[0013] The parameter measurement device 100 is a device that measures parameters of a so-called in-vehicle power storage device 200 mounted on a vehicle. The type of vehicle is not particularly limited, and may be, for example, an electric vehicle (BEV: Battery Electric Vehicle), a hybrid vehicle (HEV: Hybrid Electric Vehicle), a plug-in hybrid vehicle (PHEV: Plug-in Hybrid Electric Vehicle), etc. Although not shown in the figure, the parameter measurement device 100 is provided for each of a plurality of unit cells included in a battery module. That is, the number of parameter measurement devices 100 is the same as the number of unit cells included in the battery module. However, one parameter measurement device 100 may be provided for one battery module. That is, the number of parameter measurement devices 100 may be the same as the number of battery modules.

[0014] As shown in FIG. 1, the parameter measurement device 100 of this embodiment includes a first detection mechanism 10, a second detection mechanism 20, a switch 18, an oscillator 30, a frequency divider 40, and a control unit 50. However, the switch 18, the oscillator 30, and the frequency divider 40 are not essential, and in other embodiments, some or all of them may be omitted. The parameter measurement device 100 includes the first detection mechanism 10 and the second detection mechanism 20 as redundant parameter detection mechanisms. The first detection mechanism 10 and the second detection mechanism 20 have the same function. In other words, the first detection mechanism 10 and the second detection mechanism 20 are configured to acquire the same type of parameters.

[0015] Here, the parameters measured by the first detection mechanism 10 and the second detection mechanism 20 are voltage (V) values. However, the parameters measured by the parameter measurement device 100 may be values ​​other than voltage values, such as current, temperature, state of charge (SOC), capacity, and power consumption. When the parameters measured by the parameter measurement device 100 are electrochemical parameters such as voltage, current, and state of charge (SOC), they fluctuate minutely in a short time and have large variations, so that it is particularly effective to apply the effects of the technology disclosed herein.

[0016] As shown in FIG. 1, the first detection mechanism 10 is electrically connected to the power storage device 200 during normal vehicle running, for example, and is configured to acquire a predetermined parameter (here, a voltage value) of the power storage device 200 in a first predetermined period. The first detection mechanism 10 is controlled by a control unit 50. An oscillation signal is input to the first detection mechanism 10 from an oscillator 30. The first detection mechanism 10 is configured to acquire an acquired value (voltage value) Va based on the oscillation signal. The first detection mechanism 10 is configured to include a first FIR (Finite Impulse Response) filter 12 in addition to a first detection circuit 11 that detects the voltage of the power storage device 200. The configurations of the first detection circuit 11 and the first FIR filter 12 are not particularly limited and may be the same as those of the conventional ones.

[0017] The first FIR filter 12 is disposed between the first detection circuit 11 and the control unit 50. The filter coefficients (tap coefficients) Ci of the first FIR filter 12 are input from the control unit 50. The initial values ​​of the filter coefficients are stored in advance in a storage unit 57 of the control unit 50. In addition, as will be described in detail later, the filter coefficients Ci of the first FIR filter 12 are periodically updated by a filter coefficient learning unit 54a of the control unit 50 during normal times (such as during normal vehicle driving). The first FIR filter 12 is configured to pass a voltage value detected in a first period based on an oscillation signal input from the oscillator 30 (in other words, to remove voltage values ​​other than the voltage value detected in the first period).

[0018] As shown in FIG. 1, the second detection mechanism 20 is connected in parallel with the first detection mechanism 10 to the power storage device 200. The second detection mechanism 20 is electrically connected to the power storage device 200 when, for example, an abnormality is determined by an abnormality determination unit 51 described later, and is configured to acquire the above-mentioned parameter (here, a voltage value) in a predetermined second period longer than the first period. The second detection mechanism 20 is controlled by a control unit 50. A frequency-divided signal is input to the second detection mechanism 20 from a frequency divider 40. The second detection mechanism 20 is configured to acquire an acquired value (voltage value) Vb based on the frequency-divided signal. The second detection mechanism 20 is configured to include a second FIR filter 22 in addition to a second detection circuit 21 that detects the voltage of the power storage device 200. The configurations of the second detection circuit 21 and the second FIR filter 22 are not particularly limited and may be the same as those of the conventional ones.

[0019] The first detection mechanism 10 and the second detection mechanism 20 preferably have a heterogeneous redundant configuration. The second detection circuit 21 preferably differs from the first detection circuit 11 in at least one of the manufacturer, specifications, detection method, etc. The parameter measurement device 100 preferably has parameter detection mechanisms with heterogeneous redundant configurations.

[0020] The second FIR filter 22 is disposed between the second detection circuit 21 and the control unit 50. The filter coefficients (tap coefficients) of the second FIR filter 22 are input from the control unit 50. The initial values ​​of the filter coefficients are stored in advance in a storage unit 57 of the control unit 50. The second FIR filter 22 is configured to pass a voltage value detected in a second period based on the frequency-divided signal input from the frequency divider 40 (in other words, to remove voltage values ​​other than the voltage value detected in the second period).

[0021] The switch 18 is a switching means for switching the connection between the first detection mechanism 10 and the second detection mechanism 20. The switch 18 is controlled by the control unit 50. As shown in Fig. 1, the switch 18 connects the power storage device 200 and the first detection mechanism 10 under normal circumstances (such as when the vehicle is normally running). The switch 18 is switched so as to connect the power storage device 200 and the second detection mechanism 20 when, for example, the abnormality determination unit 51 determines that there is an abnormality.

[0022] The oscillator (CLK) 30 is an electronic circuit that generates an AC oscillation signal having a constant periodic waveform. The oscillator 30 is electrically connected to the control unit 50. The oscillator 30 outputs a CLK to the control unit 50 to operate the circuit of the control unit 50. A parameter value (specifically, a register setting) for adjusting the oscillator 30 is input from the control unit 50. The oscillator 30 is configured to generate an oscillation signal of a first period here. The configuration of the oscillator 30 is not particularly limited and may be the same as that of a conventional oscillator. The oscillation signal generated by the oscillator 30 is output to the first detection mechanism 10 and the frequency divider 40. The period of the oscillation signal output by the oscillator 30 is the sampling period for acquiring the acquired value Va by the first detection mechanism 10.

[0023] The frequency divider 40 is an electronic circuit that divides the frequency of the oscillation signal generated by the oscillator 30 (in other words, reduces it to 1 / M (M is a natural number equal to or greater than 2)) to generate a divided signal with a frequency synchronized with the oscillation signal. That is, the frequency divider 40 is an electronic circuit that generates a clock that is 1 / M times the frequency of the oscillator 30. The multiplication factor M can be set appropriately, for example, taking into consideration power consumption, accuracy, aliasing noise, and the like. The frequency divider 40 is electrically connected to the oscillator 30 and the control unit 50. The frequency divider 40 outputs a divided CLK to the control unit 50 to operate the circuit of the control unit 50. A parameter value (specifically, a register setting) that adjusts the division ratio of the frequency divider 40 is input from the control unit 50. The configuration of the frequency divider 40 is not particularly limited and may be the same as that of a conventional one. Here, the frequency divider 40 is configured to divide the oscillation signal to generate a divided signal of a second period. The frequency-divided signal generated by the frequency divider 40 is output to the second detection mechanism 20. The period of the frequency-divided signal output by the frequency divider 40 becomes the sampling period at which the second detection mechanism 20 acquires the acquired value Vb.

[0024] As shown in FIG. 1, the control unit 50 is connected to the first detection mechanism 10, the second detection mechanism 20, the switch 18, the oscillator 30, and the frequency divider 40, and is configured to be able to control the entire parameter measurement device 100. The control unit 50 is electrically connected to an ECU (Electronic Control Unit) of a vehicle (not shown). The control unit 50 of this embodiment includes an abnormality determination unit 51, a first output unit 52, a second output unit 53, a correction value calculation unit 54, a correction value output unit 55, an output selection unit 56, and a storage unit 57. However, the abnormality determination unit 51, the first output unit 52, the second output unit 53, the output selection unit 56, and the storage unit 57 are not essential, and in other embodiments, some or all of them may be omitted. In addition to the above, the control unit 50 may also include a notification unit or the like that issues a warning to a user.

[0025] The abnormality determination unit 51 is configured to determine the presence or absence of an abnormality in the first detection mechanism 10. The abnormality determination unit 51 is configured to determine the presence or absence of an abnormality, for example, by comparing the acquired value Va acquired by the first detection mechanism 10 with the acquired value Vb acquired by the second detection mechanism 20, or with a normal voltage range and / or normal voltage behavior stored in the storage unit 57. The first output unit 52 is configured to output the acquired value Va acquired by the first detection mechanism 10 as an output value to the outside (here, the ECU of the vehicle). The second output unit 53 is configured to output the acquired value Vb acquired by the second detection mechanism 20 as an output value to the outside (here, the ECU of the vehicle).

[0026] The correction value calculation unit 54 is configured to correct the acquired value Vb acquired by the second detection mechanism 20 with a correction coefficient by a predetermined process (a correction process described later) to calculate (estimate) a correction value Vc. The correction coefficient is the filter coefficient Ci of the first FIR filter 12 here. The correction value calculation unit 54 includes a filter coefficient learning unit 54a here. The filter coefficient learning unit 54a is configured to periodically calculate the filter coefficient Ci of the first FIR filter 12 in a normal state (when the vehicle is normally running) here, and to update the filter coefficient stored in the storage unit 57 as a correction coefficient as needed. The correction coefficient is updated continuously until the error satisfies the following formula (1). The correction coefficient is stored in the storage unit 57 as a coefficient during stable running of the vehicle at a timing when the following formula (1) is satisfied. This stored value is referred to when calculating the correction value Vc described later. Error ≦ α (α is, for example, 0.001)…Equation (1)

[0027] The filter coefficient learning unit 54a is configured to calculate the filter coefficient Ci of the first FIR filter 12 as a correction coefficient from the following equation (2) by the least mean square (LMS) method at predetermined time intervals (for example, every x hours (x is a natural number)).

[0028]

number

[0029] As an example, a circuit diagram (shift register circuit) of a 4 taps-FIR filter when the number of taps is 4 (N=4) is shown in FIG. 3. As is conventionally known, in FIG. 3, "+" is an adder, and D is a D flip-flop. X is the same as x in equation (2), and X n-3 is the oldest, and X n is the most recent measurement. C is the same as C in equation (2), and C 3 is the oldest, and C 0 is the most recent estimate. n is the acquired value Va.

[0030] The correction value output unit 55 is configured to output the correction value Vc corrected by the correction value calculation unit 54 as an output value to the outside (here, the ECU of the vehicle).

[0031] The output selection unit 56 is configured to select one output value to be output to the outside (here, the ECU of the vehicle) from among the acquired value Va, the acquired value Vb, and the correction value Vc, and to switch between the output from the first output unit 52, the output from the second output unit 53, and the output from the correction value output unit 55. The output selection unit 56 is configured to output the acquired value Va acquired by the first detection mechanism 10 as an output value to the outside (here, the ECU of the vehicle) when, for example, the vehicle is normally traveling or when the abnormality determination unit 51 does not determine that there is an abnormality. The output selection unit 56 is configured to output one of the acquired value Vb acquired by the second detection mechanism 20 and the correction value Vc calculated from the acquired value Vb to the outside (here, the ECU of the vehicle) as an output value when, for example, the abnormality determination unit 51 determines that there is an abnormality.

[0032] The storage unit 57 stores the filter coefficients Ci (correction coefficients) of the first FIR filter 12, the filter coefficients of the second FIR filter 22, settings (e.g., parameter values) of the oscillator 30 and the frequency divider 40, criteria for determining whether or not there is an abnormality in the first detection mechanism 10 (e.g., an allowable error between the acquired value Va and the acquired value Vb, a normal voltage range and / or normal voltage behavior), and programs and data required for the correction process performed by the correction value calculation unit 54. The storage unit 57 may further store information about the power storage device 200 (e.g., the date of manufacture, the name of the manufacturer, the name of the country of manufacture, etc.) from the power storage device 200. Note that the storage unit 57 is a part of the control unit 50 here, but in other embodiments, it may be provided outside the control unit 50 and configured to be able to communicate with the control unit 50 via wired or wireless communication.

[0033] The configuration of the control unit 50 is not particularly limited. The control unit 50 may be, for example, a microcomputer. The microcomputer may include, for example, an interface (I / F) for receiving data from an external device, a central processing unit (CPU) for executing program instructions, a read only memory (ROM) that stores the program executed by the CPU, a random access memory (RAM) used as a working area for expanding the program, and a memory for storing the program and various data.

[0034] [Control method of parameter measurement device 100] In the control method disclosed herein, when the power is turned on or the system is started, the control unit 50 sets initial values ​​of the filter coefficient Ci of the first FIR filter 12 and the filter coefficient of the second FIR filter 22. The filter coefficient Ci of the first FIR filter 12 is updated by the filter coefficient learning unit 54a whenever necessary during normal vehicle driving. In detail, the filter coefficient is calculated using the above formula (2) so that the error is reduced to the point where the above formula (1) is satisfied. Then, when the error formula set in formula (1) is established, the value of the filter coefficient at that time is stored in the storage unit 57.

[0035] During normal vehicle driving, the first detection mechanism 10 acquires the acquired value Va, and the acquired value Va acquired by the first detection mechanism 10 is output as a voltage value from the first output unit 52 to the vehicle's ECU. The vehicle's ECU includes a fault diagnosis unit (not shown) and is configured to be able to detect the occurrence of faults such as disconnection, line fault, and communication error.

[0036] Fig. 2 is a flowchart showing an example of a parameter measurement method. The measurement method in Fig. 2 is executed, for example, when a fault diagnosis flag is turned ON in an ECU (not shown) of a vehicle. In step S1, for example, during normal driving of the vehicle, a fault is detected in a fault diagnosis unit of the ECU. The fault diagnosis unit turns the fault diagnosis flag ON (for example, 1). Then, the process proceeds to step S2.

[0037] Next, in step S2, the abnormality determination unit 51 or the vehicle's host ECU determines whether or not there is an abnormality in the first detection mechanism 10. Here, based on the acquired value Va acquired by the first detection mechanism 10, it is determined whether or not an abnormality has occurred in the first detection mechanism 10. In one example, the abnormality determination unit 51 controls the switch 18 to acquire the acquired value Vb by the second detection mechanism 20 and compares it with the acquired value Va acquired by the first detection mechanism 10. Then, if the difference between the acquired value Va and the acquired value Vb is outside the allowable error previously stored in the storage unit 57, it is determined that there is an abnormality.

[0038] Alternatively, in another example, the abnormality determination unit 51 compares the acquired value Va acquired by the first detection mechanism 10 with the normal voltage range stored in the memory unit 57, and determines that an abnormality has occurred if the acquired value is outside the normal voltage range. Furthermore, the abnormality determination unit 51 acquires a change over time in the acquired value Va within a predetermined time range, and compares it with the normal voltage behavior stored in the memory unit 57, and determines that an abnormality has occurred if the acquired value differs from the normal voltage behavior, for example, if the acquired value remains fixed and does not change (sticks to high, sticks to low, etc.).

[0039] Then, if the first detection mechanism 10 does not determine that there is an abnormality (the result of step S2 is NO), it is presumed that the failure has occurred in a location other than the first detection mechanism 10. Therefore, in step S3, the first detection mechanism 10 continues to acquire the acquired value Va. Then, the output selection unit 56 selects the first output unit 52, and the first output unit 52 continues to output the acquired value Va as a voltage value. Then, the control ends.

[0040] On the other hand, if it is determined that there is an abnormality in the first detection mechanism 10 (if the result of step S2 is YES), the process proceeds to step S4. In step S4, the switch 18 is switched so as to connect the power storage device 200 and the second detection mechanism 20, and the second detection mechanism 20 acquires the acquired value Vb. It should be noted that the filter coefficient of the second FIR filter 22 remains at the initial value immediately after the switch 18 is switched. Then, in the following step S5, the output selection unit 56 selects the second output unit 53, and the acquired value Vb is output from the second output unit 53 to the ECU of the vehicle as a voltage value. In other words, the output value is switched from the acquired value Va to the acquired value Vb. Step S5 continues for nCLK (n is a natural number) after the failure diagnosis flag is turned ON in step S1. Then, the process proceeds to step S6.

[0041] In the next step S6, the correction value calculation unit 54 performs a correction process on the acquired value Vb to calculate a correction value Vc. In detail, after nCLK (n is a natural number) has elapsed since step S1, the filter coefficient of the second FIR filter 22 inherits the filter coefficient Ci of the first FIR filter 12 stored in the storage unit 57 as a correction coefficient. That is, the correction process is a process of correcting the acquired value Vb using the filter coefficient Ci of the first FIR filter 12 calculated by the filter coefficient learning unit 54a. The correction value Vc is obtained by replacing the filter coefficient of the acquired value Vb with the filter coefficient Ci of the first FIR filter 12 as a correction coefficient (for example, Vb×Ci=Vc). In other words, the calculation result with the inherited filter coefficient Ci becomes the correction value Vc.

[0042] As described above, the filter coefficient Ci as a correction coefficient is calculated by the least square error method. The least square error method is a control method for minimizing the square of the equalization error by updating the filter coefficient Ci of the FIR filter in processing measurement values ​​involving errors when performing equalization processing on measurement values. Although the least square error method increases the circuit scale, it can reduce the error from the theoretical value, thereby improving the accuracy of estimation of the correction value Vc. The calculation (estimation) of the filter coefficient Ci by the least square error method and the correction using the filter coefficient Ci are conventionally known techniques, and therefore a detailed description is omitted here.

[0043] FIG. 4(A) is a graph showing the variation of the acquired value Vb (for three cells) acquired by the second detection mechanism 20, and FIG. 4(B) is a graph showing the variation of the correction value Vc obtained by correcting the acquired value Vb of FIG. 4(A) by the correction value calculation unit 54. Here, the target value is set to 3.7V, the filter coefficient Ci of the first FIR filter 12 is obtained by the least square error method, and the acquired value Vb is corrected by the filter coefficient Ci to calculate (estimate) the correction value Vc. As can be seen from a comparison with FIG. 4(A), the variation of the value is reduced in FIG. 4(B) and it can be seen that it has converged to the target value. After the calculation of the correction value Vc is completed in this manner, proceed to step S7.

[0044] In the next step S7, when the calculation of the correction value Vc is completed, the correction value output unit 55 is selected by the output selection unit 56, and the correction value Vc is output as a voltage value from the correction value output unit 55 to the vehicle's ECU. In other words, the output value is switched from the acquired value Vb to the correction value Vc. This process is typically continued until the fault diagnosis flag of the fault diagnosis unit becomes OFF (e.g., 0). Then, the control ends.

[0045] According to the parameter measurement device 100 or measurement method described above, for example, when an abnormality such as a breakdown occurs in the first detection mechanism 10 and a second detection mechanism 20 having a longer sampling period than the first detection mechanism 10 is used, the measurement accuracy of the second detection mechanism 20 can be brought closer to the measurement accuracy of the first detection mechanism 10, thereby improving the measurement accuracy of the voltage value output to the vehicle's ECU.

[0046] Although the embodiment of the present invention has been described above, the above embodiment is merely an example. The present invention can be implemented in various other forms. The present invention can be implemented based on the contents disclosed in this specification and the technical common sense in the relevant field. The technology described in the claims includes various modifications and changes of the above-exemplified embodiment.

[0047] (1) For example, in the above embodiment, the correction value calculation unit 54 includes a filter coefficient learning unit 54a, and the correction coefficient (the filter coefficient Ci of the first FIR filter 12) is calculated by the least square error method (LMS). However, the present invention is not limited to this. In another preferred embodiment, the correction value calculation unit 54 may calculate the correction coefficient (the filter coefficient Ci of the first FIR filter 12) by linear approximation. Linear approximation is a method of controlling the error between a point expressed by a straight line using a linear function y = ax + b (x, y are the same as in the above formula (2), a is the filter coefficient Ci of the first FIR filter 12) and a measurement point so as to be minimized. Linear approximation has the advantage that it can be easily implemented and requires a small circuit scale. Note that the calculation (estimation) of the filter coefficient Ci by linear approximation is a conventionally known technique, and therefore a detailed description thereof will be omitted here.

[0048] In addition, in another preferred embodiment, for example when the first detection mechanism 10 does not have the first FIR filter 12, a correction coefficient may be calculated from the acquired value Va by arithmetic operations (in other words, without using filter coefficients) using either the least squares error method or linear approximation, and the acquired value Vb may be corrected using this correction coefficient.

[0049] (2) For example, in the above embodiment, in step S7, the correction value output unit 55 outputs the correction value Vc, and the control ends. However, this is not limited to this. The correction value calculation unit 54 may learn based on the inherited filter coefficient Ci, and further calculate the optimum value Vc' using the learned filter coefficient of the second FIR filter 22. The correction value output unit 55 may output the optimum value Vc' to the ECU of the vehicle.

[0050] (3) For example, in the above embodiment, the parameter measurement device 100 is a device that measures parameters of the in-vehicle power storage device 200. However, the present invention is not limited to this. The parameter measurement device 100 may be a device that measures parameters of a so-called stationary power storage device 200 that is installed in buildings of various facilities such as general houses, commercial facilities, hospitals, and factories. The stationary power storage device 200 may be a reused in-vehicle power storage device 200. In this case, the filter coefficient (history data) when the in-vehicle power storage device 200 was used is input to the storage unit 57, and the correction value Vc may be calculated by citing this filter coefficient Ci in the correction process. By utilizing the history data when the in-vehicle power storage device 200 was used, the effort of calculating the filter coefficient Ci can be saved.

[0051] As described above, specific aspects of the technology disclosed herein include those described in the following sections. Item 1: A parameter measurement device for an energy storage device, comprising: a first detection mechanism connected to the energy storage device and acquiring a predetermined parameter of the energy storage device in a predetermined first period; a second detection mechanism connected in parallel to the first detection mechanism to the energy storage device and acquiring the parameter of the energy storage device in a predetermined second period longer than the first period; and a control unit connected to the first detection mechanism and the second detection mechanism, wherein the control unit comprises: a correction value calculation unit that corrects an acquired value acquired by the second detection mechanism through predetermined processing to calculate a correction value, and a correction value output unit that outputs the correction value to the outside as an output value. Item 2: The control unit of the parameter measurement device described in Item 1 is configured to include an abnormality judgment unit that judges the presence or absence of the first detection mechanism, and when the abnormality judgment unit judges that there is no abnormality, to output the acquired value acquired by the first detection mechanism to the outside as the output value, and when the abnormality judgment unit judges that there is an abnormality, to output the correction value to the outside as the output value. Item 3: The parameter measurement device described in Item 2, wherein the control unit is configured such that when the abnormality determination unit determines that there is an abnormality, the correction value calculation unit starts calculating the correction value, and while the correction value is being calculated, the value acquired by the second detection mechanism is output to the outside as the output value, and when calculation of the correction value is completed, the correction value is output to the outside as the output value. Item 4: The parameter measurement device according to any one of items 1 to 3, further comprising an oscillator that generates a signal of the first period, and a frequency divider that divides the signal generated by the oscillator to generate a signal of the second period, wherein the first detection mechanism is configured to obtain a voltage value of the power storage device based on the signal generated by the oscillator, and the second detection mechanism is configured to obtain a voltage value of the power storage device based on the signal generated by the frequency divider. Item 5: The parameter measurement device described in any one of items 1 to 4, wherein the correction value calculation unit is configured to calculate a correction coefficient from the acquired value acquired by the first detection mechanism by a least squares error method, correct the acquired value acquired by the second detection mechanism with the correction coefficient, and calculate the correction value. Item 6: The parameter measurement device described in any one of Items 1 to 4, wherein the correction value calculation unit is configured to calculate a correction coefficient by linear approximation from the acquired value acquired by the first detection mechanism, correct the acquired value acquired by the second detection mechanism with the correction coefficient, and calculate the correction value. Item 7: The parameter measurement device according to item 5 or 6, wherein the first detection mechanism includes an FIR filter, and the correction coefficient is a filter coefficient of the FIR filter of the first detection mechanism. Clause 8: A method for measuring a parameter using a parameter measurement device for a power storage device, the parameter measurement device including a first detection mechanism connected to a power storage device and acquiring a predetermined parameter of the power storage device in a predetermined first period, and a second detection mechanism connected in parallel to the first detection mechanism to the power storage device and acquiring the parameter of the power storage device in a predetermined second period longer than the first period, the parameter measurement method including a correction value calculation step of correcting an acquired value acquired by the second detection mechanism using a predetermined process to calculate a correction value, and a correction value output step of outputting the correction value to the outside as an output value. [Explanation of symbols]

[0052] 10 First detection mechanism 20 Second detection mechanism 30 Oscillators 40 divider 50 Control section 51 Abnormality determination section 52 First output section 53 Second output section 54 Correction value calculation section 54a Filter coefficient learning section 55 Correction value output section 56 Output selection section 57 Memory section 100 Parameter measuring device 200 Electricity storage device

Claims

1. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; a control unit connected to the first detection mechanism and the second detection mechanism, The control unit is a correction value calculation unit that corrects the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output unit that outputs the correction value to an outside as an output value; an abnormality determination unit that determines whether or not there is an abnormality in the first detection mechanism; Equipped with When the abnormality determination unit determines that no abnormality exists, the acquired value acquired by the first detection mechanism is output to an outside as the output value; The parameter measuring device for an electricity storage device is configured to be able to output the correction value to the outside as the output value when the abnormality determination unit determines that there is an abnormality.

2. The control unit is When the abnormality determination unit determines that an abnormality exists, the correction value calculation unit starts calculating the correction value, and while the correction value is being calculated, an acquired value acquired by the second detection mechanism is output to the outside as the output value; When the calculation of the correction value is completed, the correction value is output to the outside as the output value. The parameter measuring device according to claim 1 .

3. an oscillator for generating the first periodic signal; a frequency divider that divides a frequency of a signal generated by the oscillator to generate a signal of the second period; Further equipped with The first detection mechanism obtains a voltage value of the power storage device based on a signal generated by the oscillator, The second detection mechanism is configured to obtain a voltage value of the power storage device based on the signal generated by the frequency divider.

3. The parameter measuring device according to claim 1 or 2.

4. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; a control unit connected to the first detection mechanism and the second detection mechanism, The control unit is a correction value calculation unit that corrects the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output unit that outputs the correction value to an outside as an output value; Equipped with the correction value calculation unit is configured to calculate a correction coefficient from the acquired value acquired by the first detection mechanism by a least squares error method, and to correct the acquired value acquired by the second detection mechanism with the correction coefficient to calculate the correction value. Parameter measuring device for power storage devices.

5. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; a control unit connected to the first detection mechanism and the second detection mechanism, The control unit is a correction value calculation unit that corrects the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output unit that outputs the correction value to an outside as an output value; Equipped with the correction value calculation unit is configured to calculate a correction coefficient by linear approximation from the acquired value acquired by the first detection mechanism, and to correct the acquired value acquired by the second detection mechanism with the correction coefficient to calculate the correction value. Parameter measuring device for power storage devices.

6. the first detection mechanism comprises an FIR filter; the correction coefficient is a filter coefficient of the FIR filter of the first detection mechanism; 6. The parameter measuring device according to claim 4 or 5.

7. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; A method for measuring a parameter by a parameter measuring device for a power storage device, comprising: a correction value calculation step of correcting the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output step of outputting the correction value to an outside as an output value; an abnormality determination step of determining whether or not there is an abnormality in the first detection mechanism; Including, When it is determined that no abnormality is present in the abnormality determination step, the acquired value acquired by the first detection mechanism is outputted to the outside as the output value, When it is determined that there is an abnormality in the abnormality determination step, the correction value calculation step and the correction value output step are executed, and the correction value is output to the outside as the output value. Parameter measurement methods.

8. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; A method for measuring a parameter by a parameter measuring device for a power storage device, comprising: a correction value calculation step of correcting the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output step of outputting the correction value to an outside as an output value; Including, In the correction value calculation step, a correction coefficient is calculated from the acquired value acquired by the first detection mechanism by a least squares error method, and the acquired value acquired by the second detection mechanism is corrected with the correction coefficient to calculate the correction value. Parameter measurement methods.

9. a first detection mechanism connected to the power storage device and configured to acquire a predetermined parameter of the power storage device in a first predetermined period; a second detection mechanism connected in parallel to the first detection mechanism with respect to the power storage device, the second detection mechanism acquiring the parameter of the power storage device at a predetermined second period longer than the first period; A method for measuring a parameter by a parameter measuring device for a power storage device, comprising: a correction value calculation step of correcting the acquired value acquired by the second detection mechanism through a predetermined process to calculate a correction value; a correction value output step of outputting the correction value to an outside as an output value; Including, In the correction value calculation step, a correction coefficient is calculated from the acquired value acquired by the first detection mechanism by linear approximation, and the acquired value acquired by the second detection mechanism is corrected with the correction coefficient to calculate the correction value. Parameter measurement methods.

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