Power storage cell control device and power storage module management system

1. A power storage cell control device which measures a voltage of each of a plurality of power storage cells with respect to a power storage module in which the plurality of power storage cells are connected to each other, the device comprising:

a plurality of first analog-to-digital converters (ADCs) each of which has a voltage of a different one of the plurality of power storage cells of the power storage module as an input and outputs a first digital signal corresponding to the input;

a plurality of first reference voltage portions that are provided to respectively correspond to the plurality of first ADCs and supply reference voltages used as a criterion for a conversion operation of the plurality of first ADCs;

a second ADC that outputs a second digital signal corresponding to an input voltage;

a second reference voltage portion that supplies a reference voltage used as a criterion for a conversion operation of the second ADC;

a selector that selects a reference voltage supplied from any one of the plurality of first reference voltage portions, and supplies the selected reference voltage to the second ADC as the input voltage;

a voltage value acquirer that receives a plurality of first digital signals output from a group of the plurality of first ADCs, and obtains respective voltage values of the plurality of power storage cells on the basis of the plurality of first digital signals; and

a voltage value corrector that receives a second digital signal output from the second ADC, and corrects the respective voltage values of the plurality of power storage cells obtained by the voltage value acquirer, on the basis of correction data obtained from the second digital signal.

2. The power storage cell control device of claim 1 ,

wherein the selector performs an operation of selecting the reference voltages in a cycle which is equal to or higher than a measurement cycle for the plurality of first ADCs.

3. The power storage cell control device of claim 1 ,

wherein the plurality of first ADCs receive a common clock signal, and are operated in synchronization with the common clock signal.

4. The power storage cell control device of claim 1 ,

wherein the selector selects, in a predetermined order, the reference voltages supplied from the plurality of first reference voltage portions, and repeatedly performs the operation of selecting the reference voltages, and

wherein the voltage value corrector stores correction data corresponding to each of the plurality of first reference voltage portions, and updates the stored correction data on the basis of the second digital signal when the second digital signal is received from the second ADC.

5. The power storage cell control device of claim 1 ,

wherein the plurality of first reference voltage portions supply power supply voltages and ground voltages for the plurality of corresponding first ADCs as the reference voltages.

6. The power storage cell control device of claim 1 ,

wherein the plurality of first ADCs, the plurality of first reference voltage portions, the second ADC, the second reference voltage portion, the selector, the voltage value acquirer, and the voltage value corrector are mounted on a single semiconductor device.

7. The power storage cell control device of claim 1 ,

wherein the plurality of first ADCs are delta-sigma type or incremental type ADCs, and output the first digital signals in a format of pulse density modulation (PDM) signals, and

wherein the voltage value acquirer includes a decimation filter that complements digital values with the PDM signals.

8. The power storage cell control device of claim 1 ,

wherein the plurality of first ADCs are successive comparison type, cyclic type, or slope type ADCs, and output the first digital signals as serial signals, and

wherein the voltage value acquirer includes a serial-parallel conversion circuit that converts the serial signals into parallel signals.

9. A power storage module management system comprising:

the power storage cell control device of claim 1 ;

an ammeter that measures a current flowing through the power storage module; and

a calculator that calculates a state of charge (SOC) or a state of health (SOH) of the plurality of power storage cells by using a current value measured by the ammeter and voltage values of the plurality of power storage cells output from the power storage cell control device.