Abstract: Provided are a control method and a control device for an inverter being capable of soft start using soft switching without causing a voltage surge or a current surge. A control method for soft start using soft switching of an inverter, the inverter being a bridge circuit with at least two upper and lower arms, the control method including: shifting phases of gate pulses for a switching element of the upper arm and a switching element of the lower arm, which are paired for current energization, from each other to form an overlap period of both the gate pulses; and changing magnitude of the shift to gradually increase the overlap period that defines an energization period to implement the soft start using the soft switching.

Abstract: To accurately determine whether an engine can be started while accurately detecting a degree of deterioration of a secondary battery, in a secondary battery state detecting device detecting a state of a secondary battery mounted on a vehicle, a measurement unit measures a value of an internal resistance of the secondary battery at an engine stop time. An estimation unit estimates a value of a diffusion resistance resulting from diffusion of an ion generated at an electrolytic solution of the secondary battery by supplying electric power to a starter motor at a starting time of the engine. A calculation unit calculates a starting voltage being a voltage for the starting of the engine from a resistance value obtained by adding the value of the diffusion resistance estimated by the estimation unit to the value of the internal resistance measured by the measurement unit.

Abstract: A power conversion device converting and outputting a characteristic of input power, includes: a power conversion unit including a normally-on type first switching element made of a nitride-based semiconductor material and converting the characteristic of power by a switching operation performed by the first switching element; an operation control unit controlling a switching operation of the first switching element; and an intelligent power switch including: a second switching element provided on a power input side of the power conversion unit and turning on/off power input to the power conversion unit; and a protection control unit including a current detection unit detecting a current flowing in the second switching element and controlling on/off of the second switching element and turn off the second switching element in a case where a current detected by the current detection unit exceeds a threshold value.

Abstract: A power conversion device converting and outputting a characteristic of input power, includes: a power conversion unit including a normally-on type first switching element made of a nitride-based semiconductor material and converting the characteristic of power by a switching operation performed by the first switching element; an operation control unit controlling a switching operation of the first switching element; and an intelligent power switch including: a second switching element provided on a power input side of the power conversion unit and turning on/off power input to the power conversion unit; and a protection control unit including a current detection unit detecting a current flowing in the second switching element and controlling on/off of the second switching element and turn off the second switching element in a case where a current detected by the current detection unit exceeds a threshold value.

Abstract: To learn a parameter of a simulation model of a battery efficiently. A battery internal state estimating apparatus, estimating an internal state of a battery based on a simulation model of the battery, includes a storing section (RAM10c) that stores a plurality of parameters of the simulation model, a detecting section (I/F10d) that detects a discharge current flowing from the battery to a load, a selecting section (CPU 10a) that selects a parameter to be subjected to adaptive learning based on a value of the discharge current detected by the detecting section, and an adaptive learning section (CPU 10a) that performs adapting learning on a parameter selected by the selecting section.

Abstract: The invention provides a battery condition estimating method and a power system permitting to estimate aging level or discharge ability of a battery in high precision by reducing transient changes of response voltages caused by repetitive discharges. A recovery time after a discharge is prolonged with a number of times of discharge and a relationship between the number of times of discharge and the recovery time is approximated by using an exponential function in the battery condition estimating method of the invention. A discharge pattern as shown in FIG. 1 is formed by using the recovery time obtained from this approximation and substantially constant response voltage is obtained by discharging the battery in accordance to this discharge pattern. Then, impedance during a metastable condition is calculated from the measured response voltage and the discharge current and the aging level or the discharge ability of the battery is determined from the impedance.

Abstract: To accurately determine whether an engine can be started while accurately detecting a degree of deterioration of a secondary battery, in a secondary battery state detecting device detecting a state of a secondary battery mounted on a vehicle, a measurement unit measures a value of an internal resistance of the secondary battery at an engine stop time. An estimation unit estimates a value of a diffusion resistance resulting from diffusion of an ion generated at an electrolytic solution of the secondary battery by supplying electric power to a starter motor at a starting time of the engine. A calculation unit calculates a starting voltage being a voltage for the starting of the engine from a resistance value obtained by adding the value of the diffusion resistance estimated by the estimation unit to the value of the internal resistance measured by the measurement unit.

Abstract: To learn a parameter of a simulation model of a battery efficiently. A battery internal state estimating apparatus, estimating an internal state of a battery based on a simulation model of the battery, includes a storing section (RAM10c) that stores a plurality of parameters of the simulation model, a detecting section (I/F10d) that detects a discharge current flowing from the battery to a load, a selecting section (CPU 10a) that selects a parameter to be subjected to adaptive learning based on a value of the discharge current detected by the detecting section, and an adaptive learning section (CPU 10a) that performs adapting learning on a parameter selected by the selecting section.

Abstract: The invention provides a battery condition estimating method and a power system permitting to estimate aging level or discharge ability of a battery in high precision by reducing transient changes of response voltages caused by repetitive discharges. A recovery time after a discharge is prolonged with a number of times of discharge and a relationship between the number of times of discharge and the recovery time is approximated by using an exponential function in the battery condition estimating method of the invention. A discharge pattern as shown in FIG. 1 is formed by using the recovery time obtained from this approximation and substantially constant response voltage is obtained by discharging the battery in accordance to this discharge pattern. Then, impedance during a metastable condition is calculated from the measured response voltage and the discharge current and the aging level or the discharge ability of the battery is determined from the impedance.

Abstract: A method for determining battery discharge capability includes estimating the optimum state vector X by an extended Kalman filter operation. Using the estimated state vector X, element parameters of an equivalent circuit are renewed. Furthermore, based on the equivalent circuit using the renewed element parameters, at the time of discharging with a predetermined current pattern from a battery, a voltage drop ?V is estimated. Therefore, the discharge capacity of the battery is determined.

Abstract: The method for calculating charged rate of a secondary battery is intended to calculate charged rate of a secondary battery which supplies electric power to loads, and comprises the step to measure voltage of the secondary battery more than once in a predetermined period of time after termination of charge or discharge, the step to determine the coefficients of a quadric or more exponential damping function which approximates the time characteristic of the open circuit voltage of the secondary battery by recursive calculation with the plural measured voltage values, and the step to calculate a convergent value of the open circuit voltage of the secondary battery from at least the exponential damping function with the coefficients determined above. Therefore, precise charged rate of the secondary battery can be calculated from the precise convergent value of the open circuit voltage.

Abstract: Regarding a method for determining battery discharge capability of the present invention, the optimum state vector X is estimated by extended Kalman filter operation. Using the estimated state vector X, element parameters of an equivalent circuit are renewed to the optimum (step S7). Furthermore, based on the equivalent circuit 21 using the renewed element parameters, at the time of discharging with a predetermined current pattern from a battery 12, a voltage drop ?V is estimated (step S8). Therefore the discharge capacity of the battery 12 is determined (step S9).

Abstract: A method for determining deterioration of accumulator battery hooked up with loads in a system based on results of measuring internal resistances of an accumulator battery, the method comprising the steps of; predetermining as a specified temperature a temperature at which the deterioration of the accumulator battery is determined; calculating in advance temperature correction coefficients of the internal resistances from changes of the internal resistances depending on temperatures; predetermining resistance-voltage conversion factors to convert between the internal resistances at the specified temperature and terminal discharge voltages of the accumulator battery which are obtained at the specified temperature under a condition of flowing predetermined discharge currents from the accumulator battery; measuring the internal resistances of the accumulator battery and temperature of the accumulator battery at an internal resistance measurement; converting the measured internal resistance values into the int

Abstract: The method for calculating charged rate of a secondary battery is intended to calculate charged rate of a secondary battery which supplies electric power to loads, and comprises the step to measure voltage of the secondary battery more than once in a predetermined period of time after termination of charge or discharge, the step to determine the coefficients of a quadric or more exponential damping function which approximates the time characteristic of the open circuit voltage of the secondary battery by recursive calculation with the plural measured voltage values, and the step to calculate a convergent value of the open circuit voltage of the secondary battery from at least the exponential damping function with the coefficients determined above.

Abstract: A method for determining deterioration of accumulator battery hooked up with loads in a system based on results of measuring internal resistances of an accumulator battery, the method comprising the steps of; predetermining as a specified temperature a temperature at which the deterioration of the accumulator battery is determined; calculating in advance temperature correction coefficients of the internal resistances from changes of the internal resistances depending on temperatures; predetermining resistance-voltage conversion factors to convert between the internal resistances at the specified temperature and terminal discharge voltages of the accumulator battery which are obtained at the specified temperature under a condition of flowing predetermined discharge currents from the accumulator battery; measuring the internal resistances of the accumulator battery and temperature of the accumulator battery at an internal resistance measurement; converting the measured internal resistance values into the intern

Abstract: A vehicular use power feed apparatus comprising a battery and a plurality of power distribution units connected in a loop via power feed lines. Each power distribution unit has a current monitoring circuit, a current amount determination circuit, and a current direction determination circuit, detects the direction of current and magnitude of current flowing through the power feed line, and thereby detects an occurrence of a short-circuit. A control unit exchanges information regarding occurrence of short-circuits with adjoining power distribution units via a multiplex signal transmission unit so as to pinpoint the trouble point. The control unit operates the relay switch circuits on the two sides to break the connection so as to isolate the trouble point in cooperation with the control unit of the adjoining power distribution unit. The other relay switch circuit is operated to establish a connection so as to establish a new power feed line.