Abstract: A method for detecting failure of a battery cell due to an unknown discharge current, including connecting a detector in series between the battery cell and a power supply for supplying a charging power, determining whether the charging of the battery cell progresses by the charging power in excess of a predetermined battery cell specific charging reference time, measuring a current value of the battery cell in real time if the charging of the battery cell progresses in excess of the battery cell specific charging reference time, determining whether the current value of the battery cell measured in real time exceeds a predetermined battery cell specific failure determination reference current range value, and determining a state of the battery cell as a failure state if the current value of the battery cell exceeds the predetermined battery cell specific failure determination reference current range value.

Abstract: A method for detecting failure of a battery cell due to an unknown discharge current, including connecting a detector in series between the battery cell and a power supply for supplying a charging power, determining whether the charging of the battery cell progresses by the charging power in excess of a predetermined battery cell specific charging reference time, measuring a current value of the battery cell in real time if the charging of the battery cell progresses in excess of the battery cell specific charging reference time, determining whether the current value of the battery cell measured in real time exceeds a predetermined battery cell specific failure determination reference current range value, and determining a state of the battery cell as a failure state if the current value of the battery cell exceeds the predetermined battery cell specific failure determination reference current range value.

Abstract: A method for detecting failure of a battery cell due to an unknown discharge current, including connecting a detector in series between the battery cell and a power supply for supplying a charging power, determining whether the charging of the battery cell progresses by the charging power in excess of a predetermined battery cell specific charging reference time, measuring a current value of the battery cell in real time if the charging of the battery cell progresses in excess of the battery cell specific charging reference time, determining whether the current value of the battery cell measured in real time exceeds a predetermined battery cell specific failure determination reference current range value, and determining a state of the battery cell as a failure state if the current value of the battery cell exceeds the predetermined battery cell specific failure determination reference current range value.

Abstract: Provided is a method for detecting failure of a battery cell due to an unknown discharge current, and the method includes connecting a detector in series between the battery cell and a power supply for supplying a charging power, determining whether the charging of the battery cell progresses by the charging power in excess of a predetermined battery cell specific charging reference time, measuring a current value of the battery cell in real time if the charging of the battery cell progresses in excess of the battery cell specific charging reference time, determining whether the current value of the battery cell measured in real time exceeds a predetermined battery cell specific failure determination reference current range value, and determining a state of the battery cell as a failure state in which an unknown discharge occurs if the current value of the battery cell exceeds the predetermined battery cell specific failure determination reference current range value.

Abstract: A power quality monitoring apparatus is developed for a railway power system. The apparatus is calculating the energy flow and the power consumption and recording the by using the voltage and current sensors at AC and DC power source in the various industrial fields. The voltage and current phases are detected for the AC power. The direction of current is detected to calculate the power consumption for the DC power. Then, the detected data is analyzed. It is possible to monitor the variation of the voltages and current values of the railway vehicle in real time. It is possible to display the variations of the vehicle loads, the AC power output, the voltage and current value fluctuations, the power consumption and power flows in a form of the graphic or text format. Thereby, it is possible to easily understand the overall status of the overhead line's environment.

Abstract: An energy storage apparatus has developed for railway vehicles by adopting a bidirectional DC-DC converter to increase the efficiency of charge/discharge, comprising that; a power receiving unit, filter unit, charging unit storage unit having a plurality of super-capacitors, capacitor monitoring unit, a plurality of bidirectional DC-DC converters arranged in parallel, and voltage detector electrically connected to the filter unit, current detector for detecting the currents flowing. The controller further comprises; an analog interface board, signal identifying board, signal control board, digital output contact unit, communicating board, PWM control board, optical output board, external gate driver. The PWM control board includes; a sensor input circuit, A/D converter, calculation unit, calculation control processor, and power monitoring unit.

Abstract: An energy storage apparatus has developed for railway vehicles by adopting a bidirectional DC-DC converter to increase the efficiency of charge/discharge, comprising that; a power receiving unit, filter unit, charging unit storage unit having a plurality of super-capacitors, capacitor monitoring unit, a plurality of bidirectional DC-DC converters arranged in parallel, and voltage detector electrically connected to the filter unit, current detector for detecting the currents flowing. The controller further comprises; an analog interface board, signal identifying board, signal control board, digital output contact unit, communicating board, PWM control board, optical output board, external gate driver. The PWM control board includes; a sensor input circuit, A/D converter, calculation unit, calculation control processor, and power monitoring unit.

Abstract: A power quality monitoring apparatus is developed for a railway power system. The apparatus is calculating the energy flow and the power consumption and recording the by using the voltage and current sensors at AC and DC power source in the various industrial fields. The voltage and current phases are detected for the AC power. The direction of current is detected to calculate the power consumption for the DC power. Then, the detected data is analyzed. It is possible to monitor the variation of the voltages and current values of the railway vehicle in real time. It is possible to display the variations of the vehicle loads, the AC power output, the voltage and current value fluctuations, the power consumption and power flows in a form of the graphic or text format. Thereby, it is possible to easily understand the overall status of the overhead line's environment.

Abstract: An automatic tuning method is developed for an energy storage system of the railway vehicle. The method comprises; an optimal tracking for voltage fluctuation in the overhead line voltage varying with hourly-basis, the voltage variation of the substation and railway vehicle operating pattern. The railway vehicle is automatically performed the tuning to maximize the energy storing efficiency. The railway vehicle can achieve the optimum operation for saving energy effectively by bidirectional DC/DC converter using regenerative energy of DC. The railway vehicle stably operates under the overhead line voltage fluctuation. The energy efficiency is maximized by charging/discharging energy while the power is tracking unstable, which is generated by utilizing natural energies such as wind or solar energy, in real time by applying an automatic tuning algorithm to an energy storage system which is applied to a smart grid or a micro grid that uses renewable energy as a primary energy source.