A solenoid actuator is a type of energy converter that changes an external supply of electrical energy into mechanical energy. It is small, lightweight, and resistant to contamination. It also has the advantages of rapid dynamic response and economic feasibility, ensuring that it is used widely in a...
A solenoid actuator is a type of energy converter that changes an external supply of electrical energy into mechanical energy. It is small, lightweight, and resistant to contamination. It also has the advantages of rapid dynamic response and economic feasibility, ensuring that it is used widely in a variety of industrial fields.
With recent regulations in force to reduce air pollution and CO2 emissions, automobiles with internal combustion engines running on fossil fuels are replaced with eco-friendly automobiles that use clean diesel, natural gas, or hydrogen as fuels. The hydrogen fuel cell vehicle, which is considered the most promising type of eco-friendly vehicle, stores hydrogen at an ultra-high pressure of 70 MPa in order to ensure competitiveness in its cruising speeds compared to existing internal combustion engine vehicles. The supply of hydrogen from the hydrogen fuel storage cylinder into the fuel cell stack is controlled via the on/off operation of a solenoid attached to the storage cylinder valve. Unlike the conventional solenoids being used in pneumatic solenoid valves, the solenoid for the hydrogen storage cylinder should be designed to ensure structural safety and operability under ultra-high pressure conditions.
In this study a new structure and operating mechanism for the solenoid actuator, comprising a double-type plunger to allow operation under ultra-high pressure conditions, has been developed taking into design consideration hydrogen leakage, power consumption, saturation temperature, and structural safety. The actuator consists of a coil generating magnetic fields, a plunger activated by the magnetic fields, and a guide that supports the ultra-high pressure and directs the motion.
The minimum thickness of the guide is calculated using the design equation for a pressurized container, and its validity is verified through the structural and stress analysis based on ASME code. As to leakage-external and internal, the O-ring used at the joint to prevent the external leakage is selected based on the previous study results and relevant standards. The spring used to prevent the internal leakage and the plunger return is selected through an analysis of the contact pressure between the internal components. The length of the guide and the plunger, which affect the attraction force of the solenoid actuator, is optimized via the electromagnetic field analysis, and the effect of the plunger shape on the fluid force is analyzed through the flow analysis.
The actuator coil needs to provide the necessary attraction force even at any saturation temperature caused by long operation of the vehicle. The simplified prediction equations for the saturation temperature and the attraction force are suggested in terms of design parameters of coil such as the bobbin shape, the number of windings, and the wire diameter. The validity of both equations are verified because the saturation temperature(72.8 ℃)and the attraction force(16.4 N) predicted by the equations match to the calculated values by heat transfer analysis and electromagnetic analysis with errors of 25 ℃ and 3.5 N, respectively. Those design parameters are optimized by minimizing the power consumption while maximizing the attraction force. The required maximum attraction force of the solenoid is determined by considering the safety factor at the maximum pressure condition.
Using a testing device composed of a thermocouple and a load cell the temperature and the attraction force are measured. The measured saturation temperature 6.4 ℃ lower with respect to the analysis results. The attraction force measured at both room and saturation temperatures 2.00 N and 2.93 N weaker than the analysis results, respectively. Through real tests under the ultra-high pressure condition. It is verified that the performance index satisfies the commercial standards.
A solenoid actuator is a type of energy converter that changes an external supply of electrical energy into mechanical energy. It is small, lightweight, and resistant to contamination. It also has the advantages of rapid dynamic response and economic feasibility, ensuring that it is used widely in a variety of industrial fields.
With recent regulations in force to reduce air pollution and CO2 emissions, automobiles with internal combustion engines running on fossil fuels are replaced with eco-friendly automobiles that use clean diesel, natural gas, or hydrogen as fuels. The hydrogen fuel cell vehicle, which is considered the most promising type of eco-friendly vehicle, stores hydrogen at an ultra-high pressure of 70 MPa in order to ensure competitiveness in its cruising speeds compared to existing internal combustion engine vehicles. The supply of hydrogen from the hydrogen fuel storage cylinder into the fuel cell stack is controlled via the on/off operation of a solenoid attached to the storage cylinder valve. Unlike the conventional solenoids being used in pneumatic solenoid valves, the solenoid for the hydrogen storage cylinder should be designed to ensure structural safety and operability under ultra-high pressure conditions.
In this study a new structure and operating mechanism for the solenoid actuator, comprising a double-type plunger to allow operation under ultra-high pressure conditions, has been developed taking into design consideration hydrogen leakage, power consumption, saturation temperature, and structural safety. The actuator consists of a coil generating magnetic fields, a plunger activated by the magnetic fields, and a guide that supports the ultra-high pressure and directs the motion.
The minimum thickness of the guide is calculated using the design equation for a pressurized container, and its validity is verified through the structural and stress analysis based on ASME code. As to leakage-external and internal, the O-ring used at the joint to prevent the external leakage is selected based on the previous study results and relevant standards. The spring used to prevent the internal leakage and the plunger return is selected through an analysis of the contact pressure between the internal components. The length of the guide and the plunger, which affect the attraction force of the solenoid actuator, is optimized via the electromagnetic field analysis, and the effect of the plunger shape on the fluid force is analyzed through the flow analysis.
The actuator coil needs to provide the necessary attraction force even at any saturation temperature caused by long operation of the vehicle. The simplified prediction equations for the saturation temperature and the attraction force are suggested in terms of design parameters of coil such as the bobbin shape, the number of windings, and the wire diameter. The validity of both equations are verified because the saturation temperature(72.8 ℃)and the attraction force(16.4 N) predicted by the equations match to the calculated values by heat transfer analysis and electromagnetic analysis with errors of 25 ℃ and 3.5 N, respectively. Those design parameters are optimized by minimizing the power consumption while maximizing the attraction force. The required maximum attraction force of the solenoid is determined by considering the safety factor at the maximum pressure condition.
Using a testing device composed of a thermocouple and a load cell the temperature and the attraction force are measured. The measured saturation temperature 6.4 ℃ lower with respect to the analysis results. The attraction force measured at both room and saturation temperatures 2.00 N and 2.93 N weaker than the analysis results, respectively. Through real tests under the ultra-high pressure condition. It is verified that the performance index satisfies the commercial standards.
주제어
#초고압 수소 이중플런저 솔레노이드
※ AI-Helper는 부적절한 답변을 할 수 있습니다.