State of charge estimation device and method of estimating state of charge

摘要

A state of charge estimation device for estimating a state of charge of an electric storage device includes a voltage measurement component, a current measurement component, and a controller component. The controller component is configured to, when estimation of state of charge of the electric storage device based on an accumulated amount of currents measured by the current measurement component is defined as a current accumulation method and the estimation based on an open circuit voltage (OCV) of the electric storage device measured by the voltage measurement component is defined as an OCV method, permit estimation of state of charge by the OCV method when a condition that an error in estimation of state of charge of the electric storage device by the current accumulation method exceeds an error in estimation of state of charge of the electric storage device by the OCV method is satisfied.

主权项

1. A state of charge estimation device for estimating a state of charge of an electric storage device, the state of charge estimation device comprising:
a voltage measurement component configured to measure a voltage across the electric storage device; a current measurement component configured to measure a current flowing through the electric storage device; and a controller component configured to, when an estimation of the state of charge of the electric storage device based on an accumulated amount of currents measured by the current measurement component is defined as a current accumulation method and an estimation of the state of charge of the electric storage device based on an open circuit voltage (OCV) of the electric storage device measured by the voltage measurement component is defined as an OCV method, permit the estimation of the state of charge by the OCV method when a condition that an error in the estimation of the state of charge of the electric storage device by the current accumulation method exceeds an error in estimation of the state of charge of the electric storage device by the OCV method is satisfied, wherein the condition that the error in the estimation of the state of charge of the electric storage device by the current accumulation method exceeds the error in the estimation of the state of charge of the electric storage device by the OCV method includes a condition that an increase/decrease in a remaining capacity of the electric storage device since a previous estimation by the OCV method exceeds an increase/decrease in the remaining capacity corresponding to the error in the previous estimation by the OCV method.