Abstract: A battery system includes: a plurality of battery banks connected in parallel with each other; and a distribution controller coupled to the battery banks and configured to: receive a command comprising a target charging/discharging amount; determine a priority order between the battery banks based on a state of charge (SOC) and a state of health (SOH) of each of the battery banks; select at least some of the battery banks to be charged or discharged according to the target charging/discharging amount based on the priority order; and perform a charging or discharging on the at least some of the battery banks according to the target charging/discharging amount so that others of the battery banks are paused.

Abstract: A power assist apparatus includes a branch power lines, a first power storage device, a power assist converter, and a second power storage device. The branch power line is connected to a main line of a natural energy power generation system, which is connected to a system. The first power storage device connected to the branch power line. The power assist converter connected to the branch power line. The second power storage device connected to a downstream side of the power assist converter.

Abstract: A battery system includes: a plurality of battery banks connected in parallel with each other; and a distribution controller coupled to the battery banks and configured to: receive a command comprising a target charging/discharging amount; determine a priority order between the battery banks based on a state of charge (SOC) and a state of health (SOH) of each of the battery banks; select at least some of the battery banks to be charged or discharged according to the target charging/discharging amount based on the priority order; and perform a charging or discharging on the at least some of the battery banks according to the target charging/discharging amount so that others of the battery banks are paused.

Abstract: A power assist apparatus includes a branch power lines, a first power storage device, a power assist converter, and a second power storage device. The branch power line is connected to a main line of a natural energy power generation system, which is connected to a system. The first power storage device connected to the branch power line. The power assist converter connected to the branch power line. The second power storage device connected to a downstream side of the power assist converter.

Abstract: A power supply system includes an inverter controller which amplifies a deviation between a bus voltage command signal and a bus voltage signal obtained by detecting a bus voltage, inputs the amplified deviation to a first limit unit for limiting output power of a commercial power supply, divides the deviation into a first deviation within a first limit value of the first limit unit and a second deviation which exceeds a range of the first limit value, and controls an inverter on the basis of the first deviation, and a DC/DC converter controller which controls a DC/DC converter on the basis of the second deviation.

Abstract: A power supply system includes an inverter controller which amplifies a deviation between a bus voltage command signal and a bus voltage signal obtained by detecting a bus voltage, inputs the amplified deviation to a first limit unit for limiting output power of a commercial power supply, divides the deviation into a first deviation within a first limit value of the first limit unit and a second deviation which exceeds a range of the first limit value, and controls an inverter on the basis of the first deviation, and a DC/DC converter controller which controls a DC/DC converter on the basis of the second deviation.

Abstract: A power supply system comprises a battery which can be charged/discharged, a charging/discharging apparatus which charges/discharges the battery, and a charging/discharging power limit controller which outputs a charging/discharging power limit control signal obtained by amplifying a deviation between an output voltage command signal of the battery and a detected output voltage signal obtained by detecting an output voltage of the battery, wherein and the charging/discharging apparatus includes a charging/discharging controller which controls of charging/discharging power of the battery based on the charging/discharging power limit control signal.

Abstract: A parallel inverter system needs neither a dedicated line for synchronizing common portions nor switching operations, and includes a plurality of inverter units operating in parallel. An inverter control circuit of each inverter unit includes a sinusoidal signal generating circuit, a PWM control signal generating circuit, a phase difference circuit, a frequency difference circuit, and a feedback circuit. The feedback circuit inputs to the sinusoidal signal generating circuit an addition result value which is obtained by adding to a commanded value for reference frequency a value obtained from multiplication of a phase difference by a predetermined gain and a value obtained from multiplication of a frequency difference by a predetermined gain. The phase difference among outputs from the inverter units occurring in the parallel operation of the inverter units is reduced by changing the output frequencies of the inverter units.

Abstract: There is herein provided an uninterruptible power supply device with a degradation judgment circuit of a storage battery which can perform an exact judgment, continuing the power supply to a load apparatus stably without giving the excessive burden to the storage battery. The storage battery is floatingly charged from a rectifier connected with the power source. The device has the control circuit for controlling the output voltage of the rectifier and the degradation judgment circuit. The output voltage of the rectifier is lowered to below a steady state by the control circuit. As a result, the storage battery discharges with the current Idc restricted rather than rated discharge current. And a part of power supply is supplied to the load. The degradation judgment circuit judges the degradation of the storage battery based on the discharge voltage Vdc.

Abstract: There is herein provided an uninterruptible power supply device with a degradation judgment circuit of a storage battery which can perform an exact judgment, continuing the power supply to a load apparatus stably without giving the excessive burden to the storage battery. The storage battery is floatingly charged from a rectifier connected with the power source. The device has the control circuit for controlling the output voltage of the rectifier and the degradation judgment circuit. The output voltage of the rectifier is lowered to below a steady state by the control circuit. As a result, the storage battery discharges with the current Idc restricted rather than rated discharge current. And a part of power supply is supplied to the load. The degradation judgment circuit judges the degradation of the storage battery based on the discharge voltage Vdc.

Abstract: There is herein provided an uninterruptible power supply device with a degradation judgment circuit 4 of a storage battery 2 which can perform an exact judgment, continuing the power supply to a load apparatus 8 stably without giving the excessive burden to the storage battery 2. The storage battery 2 is floatingly charged from a rectifier 1 connected with the power source 10. The device has the control circuit 3 for controlling the output voltage of the rectifier 1 and the degradation judgment circuit 4. The output voltage of the rectifier 1 is lowered to below a steady state by the control circuit 3. As a result, the storage battery 2 discharges with the current Idc restricted rather than rated discharge current. And a part of power supply is supplied to the load 8. The degradation judgment circuit 4 judges the degradation of the storage battery based on the discharge voltage Vdc.

Abstract: An uninterruptible power supply apparatus, enabling to detect an interruption on a commercial power supply, with certainty, to be turned into a battery operation, but not due to a momentary voltage-drop, unnecessarily, comprises: a rectifier (REC) 210 for converting an AD power inputted from a commercial power supply 100 into a AC power; an inverter (INV) 220 for converting the DC electric power into a desired AC power, to be supplied to a load 300; a battery 230 connected between those; a controller circuit 250 for controlling those power converters; and further, an interruption detection circuit 260 made from a frequency detection circuit, as a means for detecting an abnormality on the AC power inputted from the commercial power supply, whereby detecting the interruption, without responding to the momentary voltage-drop, while the controller circuit has a limiter 253 for protecting the rectifier from overload when the momentary voltage-drop occurs.

Abstract: A parallel inverter system needs neither a dedicated line for synchronizing common portions nor switching operations, and includes a plurality of inverter units operating in parallel. An inverter control circuit of each inverter unit includes a sinusoidal signal generating circuit, a PWM control signal generating circuit, a phase difference circuit, a frequency difference circuit, and a feedback circuit. The feedback circuit inputs to the sinusoidal signal generating circuit an addition result value which is obtained by adding to a commanded value for reference frequency a value obtained from multiplication of a phase difference by a predetermined gain and a value obtained from multiplication of a frequency difference by a predetermined gain. The phase difference among outputs from the inverter units occurring in the parallel operation of the inverter units is reduced by changing the output frequencies of the inverter units.

Abstract: The uninterruptible power supply apparatus comprises an AC switch for turning on/off the AC power that is input from a commercial AC power source; a storage battery; a power conversion device; a load device connected to the output end of the AC switch; an output AC voltage detection unit for detecting an output AC voltage that is output from the AC switch; and an abnormality detection circuit for detecting that the detected output AC voltage is outside predefined upper and lower limits; wherein said AC switch turns off in accordance with a signal detected by said abnormality detection circuit. Further comprises a restoration circuit for generating a restoration signal when the AC voltage detected by an input AC voltage detection unit exceeds at least a lower-limit AC voltage setting that is increased gradually or continuously in accordance with a load factor computed by a load factor computation circuit.

Abstract: An uninterruptible power supply apparatus, enabling to detect an interruption on a commercial power supply, with certainty, to be turned into a battery operation, but not due to a momentary voltage-drop, unnecessarily, comprises: a rectifier (REC) 210 for converting an AD power inputted from a commercial power supply 100 into a DC power; an inverter (INV) 220 for converting the DC electric power into a desired AC power, to be supplied to a load 300; a battery 230 connected between those; a controller circuit 250 for controlling those power converters; and further, an interruption detection circuit 260 made from a frequency detection circuit, as a means for detecting an abnormality on the AC power inputted from the commercial power supply, whereby detecting the interruption, without responding to the momentary voltage-drop, while the controller circuit has a limiter 253 for protecting the rectifier from overload when the momentary voltage-drop occurs.

Abstract: In a periodic signal controller of the present invention, a first phase difference detection circuit 1 and a first sine-wave signal generation circuit 2 constitute a phase-locked loop for processing instantaneous values. A frequency difference detection circuit 4 determines a frequency difference between AC input and output signals, using instantaneous values of a first sine-wave signal output from the first sine-wave generation circuit 2 and a second sine-wave signal output from a second sine-wave signal generation circuit 9. A second phase difference detection circuit 3 determines a phase difference between the first and second sine-wave signals. An adder circuit 5 adds a phase difference detection signal to a frequency difference detection signal.

Abstract: The uninterruptible power supply apparatus comprises an AC switch for turning on/off the AC power that is input from a commercial AC power source; a storage battery; a power conversion device; a load device connected to the output end of the AC switch; an output AC voltage detection unit for detecting an output AC voltage that is output from the AC switch; and an abnormality detection circuit for detecting that the detected output AC voltage is outside predefined upper and lower limits; wherein said AC switch turns off in accordance with a signal detected by said abnormality detection circuit. Further comprises a restoration circuit for generating a restoration signal when the AC voltage detected by an input AC voltage detection unit exceeds at least a lower-limit AC voltage setting that is increased gradually or continuously in accordance with a load factor computed by a load factor computation circuit.

Abstract: There is herein provided an uninterruptible power supply device with a degradation judgment circuit 4 of a storage battery 2 which can perform an exact judgment, continuing the power supply to a load apparatus 8 stably without giving the excessive burden to the storage battery 2. The storage battery 2 is floatingly charged from a rectifier 1 connected with the power source 10. The device has the control circuit 3 for controlling the output voltage of the rectifier 1 and the degradation judgment circuit 4. The output voltage of the rectifier 1 is lowered to below a steady state by the control circuit 3. As a result, the storage battery 2 discharges with the current Idc restricted rather than rated discharge current. And a part of power supply is supplied to the load 8. The degradation judgment circuit 4 judges the degradation of the storage battery based on the discharge voltage Vdc.

Abstract: In a periodic signal controller of the present invention, a first phase difference detection circuit 1 and a first sine-wave signal generation circuit 2 constitute a phase-locked loop for processing instantaneous values. A frequency difference detection circuit 4 determines a frequency difference between AC input and output signals, using instantaneous values of a first sine-wave signal output from the first sine-wave generation circuit 2 and a second sine-wave signal output from a second sine-wave signal generation circuit 9. A second phase difference detection circuit 3 determines a phase difference between the first and second sine-wave signals. An adder circuit 5 adds a phase difference detection signal to a frequency difference detection signal.

Abstract: An uninterruptible power supply is provided that is capable of turning off an AC switch made up of thyristors as quickly as possible by using a power converter. A power is supplied from the utility power supply 3 to the load 9 through the AC switch 1 made up of antiparallelly connected thyristors. Under this condition, in the event that the power failure detection means 12 detects a power outage, if the current detection means 11a detects a current of a positive polarity, the reference sinusoidal voltage generation circuit 11 generates the high synchronous sinusoidal voltage Vref2 which is higher, by the voltage difference command value &Dgr;V, than the synchronous sinusoidal voltage Vref1 in phase with the utility power supply.