This study proposed a battery management approach for the electric hydraulic pump system of a lifting trolley.The pump system was powered by two 12-V lead-acid batteries in series.Because direct measurement of the act...This study proposed a battery management approach for the electric hydraulic pump system of a lifting trolley.The pump system was powered by two 12-V lead-acid batteries in series.Because direct measurement of the actual battery state of charge is unlikely,it has mostly been determined through estimation based on the measured open-circuit voltage.A discharge current will result in a voltage drop and hence a lower voltage during discharge;however,the battery voltage will return to the original open-circuit voltage once the discharge stops.The operating current of the electric hydraulic pump system employed in this study was associated with three factors:the lifting height,lifting load,and battery state of charge.The operating current remained constant during the first half of the lifting phase and increased gradually with the lifting height in the second half.The operating current peaked when the lifting height reached the maximum.The power management approach for the electric hydraulic pump system featured the following basic functions:overcharge protection,overdischarge protection,short-circuit protection,overload protection,and an operating timer established in accordance with the system’s operating current variation.According to the manufacturer-defined maximum lifting load and lifting height of the lifting trolley,this study conducted experiments to obtain the maximum required operating time.An operating time greater than the maximum required operating time indicates the occurrence of an unexpected event,discharge should be stopped until the fault is resolved.展开更多
Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sen...Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sensing component,the output current is adjusted to achieve a set temperature.However,the temperature of the heating film is nonuniformly distributed,and determining the correct output current is time-consuming.This study adopted finite element heat transfer analysis to determine a heating method(such as heat power and heat flux)for an ITO conductive heating film system.The results of the analysis may serve as a reference for temperature compensation in ITO conductive heating films.展开更多
文摘This study proposed a battery management approach for the electric hydraulic pump system of a lifting trolley.The pump system was powered by two 12-V lead-acid batteries in series.Because direct measurement of the actual battery state of charge is unlikely,it has mostly been determined through estimation based on the measured open-circuit voltage.A discharge current will result in a voltage drop and hence a lower voltage during discharge;however,the battery voltage will return to the original open-circuit voltage once the discharge stops.The operating current of the electric hydraulic pump system employed in this study was associated with three factors:the lifting height,lifting load,and battery state of charge.The operating current remained constant during the first half of the lifting phase and increased gradually with the lifting height in the second half.The operating current peaked when the lifting height reached the maximum.The power management approach for the electric hydraulic pump system featured the following basic functions:overcharge protection,overdischarge protection,short-circuit protection,overload protection,and an operating timer established in accordance with the system’s operating current variation.According to the manufacturer-defined maximum lifting load and lifting height of the lifting trolley,this study conducted experiments to obtain the maximum required operating time.An operating time greater than the maximum required operating time indicates the occurrence of an unexpected event,discharge should be stopped until the fault is resolved.
文摘Indium tin oxide(ITO)heating film is primarily used as the defogging component of an instrument observation window.Conventionally,a constant current is used to heat the film.Through the feedback of the temperature sensing component,the output current is adjusted to achieve a set temperature.However,the temperature of the heating film is nonuniformly distributed,and determining the correct output current is time-consuming.This study adopted finite element heat transfer analysis to determine a heating method(such as heat power and heat flux)for an ITO conductive heating film system.The results of the analysis may serve as a reference for temperature compensation in ITO conductive heating films.
