588 results about "Intake pressure" patented technology

The invention discloses a supercharging optimization control method based on ignition efficiency, which comprises the following steps of: periodically detecting a supercharging closed-loop enabling condition for an engine, and when the state of the engine is changed from a state meeting the supercharging closed-loop enabling condition to a state not meeting the supercharging closed-loop enabling condition, starting the ignition efficiency; according to the ratio of the actual outlet pressure to the actual inlet pressure of the throttle valve and the current real-time rotating speed of the engine, the initial duration value when the target opening degree of the supercharging actuator is kept unchanged is determined; determining remaining time according to the duration initial value, and updating and optimizing the remaining time according to the ignition angle efficiency variable quantity to obtain optimized remaining time; and the optimized remaining time serves as the maintaining time of the opening degree of the pressurization actuator through pressurization closed-loop enabling, and the pressurization process is controlled according to the maintaining time. According to the method, the problems of control smoothness and stability possibly caused when the pressurization closed loop is quitted are optimized, and the stability of the air inlet pressure and the pressure of an outlet of the supercharger in the quitting process of the pressurization closed loop is improved.

The invention relates to a method and device for obtaining the actual supercharging pressure of an engine. The method comprises the steps that the air inlet pressure of an outlet of a throttle valve and the air inlet pressure of an inlet of the throttle valve are obtained; and judging whether the throttle valve is in a normal control mode, an anti-overshoot control mode or a full-open control mode, and for different modes, selecting corresponding transition coefficients to calculate the actual boost pressure of the engine by combining the intake pressure of the outlet of the throttle valve and the intake pressure of the inlet of the throttle valve. According to the method, on the basis of different working modes of the throttle valve, the boost pressure control deviation, the intake pressure control deviation and the intake pressure response condition are considered at the same time, the calculation method of the actual boost pressure is optimized, meanwhile, learning parameters of the actual boost pressure are continuously updated in different life cycles, and the control precision of the intake pressure is improved.

The invention relates to a gas turbine engine, a starting method and system of the gas turbine engine and a medium. The starting method comprises the steps that S1, a high-pressure rotor of the gas turbine engine is driven by an air turbine starter to rotate, the rotating speed of the high-pressure rotor is subjected to closed-loop control according to the air inlet pressure of the air turbine starter to reach the set rotating speed, and whether the engine rotor has the thermal bending effect or not is judged according to a vibration signal of the high-pressure rotor of the engine; and S2, if it is judged that the hot bending effect exists in the step S1, closed-loop control is conducted on the rotating speed of the high-pressure rotor according to the air inlet pressure of the air turbine starter, and the rotating speed is maintained to the set rotating speed till whether the engine rotor has the hot bending effect or not is judged according to the vibration signal of the high-pressure rotor of the engine.

The invention relates to the technical field of medical instruments, and provides a pneumoperitoneum machine pressure measurement abnormity control method which comprises the following steps: acquiring air inlet pressure, pressure measurement pressure and smoke exhaust pressure; calculating a difference value between the air inlet pressure and the pressure measuring pressure and a difference value between the pressure measuring pressure and the smoke exhaust pressure; when the difference value between the air inlet pressure and the pressure measuring pressure is larger than a first preset difference value and smaller than a second preset difference value, and the difference value between the pressure measuring pressure and the smoke discharging pressure is larger than a third preset difference value and smaller than a fourth preset difference value, the pressure measuring pressure is selected as display pressure; otherwise, starting a first pressure measurement abnormity detection program. By monitoring the difference value between the air inlet pressure and the measured pressure and the change of the difference value between the measured pressure and the smoke exhaust pressure, pressure monitoring abnormity caused by equipment faults in the operation process can be recognized, the equipment stability is improved, and the operation risk is reduced.

To early activate a catalyst of a three-way catalyst device for purifying exhaust gas of an internal combustion engine, in a power device including the internal combustion engine using ammonia and ignition fuel as fuel.SOLUTION: A power plant 10 comprises a turbocharger 26 that turbocharges intake air of an internal combustion engine 12 to increase an intake pressure, and a throttle valve 24 that narrows a flow path of an intake pipe 22. When a catalyst in a three-way catalytic device 44 is inactive, a wastegate valve 50 of the turbocharger 26 is opened, or in addition, an intake flow path is narrowed by the throttle valve 24, to lower the intake pressure compared to that in normal time. The lowering of the intake pressure reduces a heat capacity of materials in a cylinder, increases a combustion temperature, and increases an exhaust temperature. High-temperature exhaust gas increases a temperature of the catalyst early, to accelerate activation.SELECTED DRAWING: Figure 1

The invention discloses an air inlet pressure and temperature sensor resistor and shell assembling device which comprises a divider rotary table, a tool, an operation opening, a forming pin, a shell feeding mechanical arm, a resistor feeding mechanical arm and a shaping die. An operation opening used for opening a resistor pin is formed in the tool, the divider rotary table is provided with a forming pin in butt joint with the operation opening, the forming pin is used for directionally bending the resistor pin, and the tool is in butt joint with the shell feeding mechanical arm and the resistor feeding mechanical arm. By means of the mode, according to the air inlet pressure and temperature sensor resistor and shell assembling equipment, pre-shaping treatment is conducted on resistor pins through the shaping die, fine fixed-point bending operation on the pins is accurately achieved through the forming pins, and resistor welding and UV curing stations are integrated in the whole machine; the automatic production and processing of the resistance part of the air inlet pressure sensor are efficiently realized, and the productivity and the yield are obviously improved.

The invention discloses a test system and a test method for high-temperature solid oxide water electrolysis hydrogen production. The test system comprises a gas supply device, a heating unit, a back pressure stabilizing unit and a control unit, the back pressure stabilizing unit is connected with a cathode outlet of the SOEC stack and comprises a back pressure sensor, a first pressure regulating valve and a variable-frequency speed regulating induced draft fan; and the control unit takes back pressure data acquired by the back pressure sensor and air inlet pressure data acquired by the air inlet sensor arranged at the cathode inlet of the SOEC stack as parameters, and generates an adjusting instruction of the first pressure adjusting valve and / or the variable frequency speed adjusting induced draft fan according to a preset rule. According to the invention, performance testing can be carried out on a large-scale single electric pile and a module group composed of a plurality of small-scale or medium-scale electric piles in a large-power range; in addition, different combination modes of series connection and parallel connection between multiple electric piles and the change rule of the electrolysis performance can be tested, and then a more compact and efficient multi-electric-pile matching module can be obtained.

The invention discloses a supercharging control method, device and equipment, a storage medium and a product, and relates to the technical field of engine control. The method comprises the steps that when a supercharging actuator quits supercharging closed-loop enabling, the initial opening maintaining duration of the supercharging actuator is determined, and the initial opening maintaining duration of the supercharging actuator is determined; the initial opening maintaining duration is a duration initial value when the target opening of the actuator corresponding to the supercharging actuator is kept unchanged; on the basis of the throttle valve working control mode, the initial opening maintaining duration is optimized, and the optimized opening maintaining duration is obtained; and pressurization control is conducted according to the optimized opening maintaining duration. According to the method, when the pressurization actuator quits the pressurization closed loop enabling, the problems of air inlet control smoothness and stability possibly caused when the pressurization closed loop quits are optimized, and the maintaining duration control of the target opening degree of the pressurization actuator after the pressurization closed loop quits is optimized; the stability of the air inlet pressure and the pressure of an outlet of the supercharger in the pressurization closed loop quitting process is improved.

The compressor air inlet pressure stabilizing device comprises a compressor, and the compressor is provided with an air inlet; the compressor air inlet pressure stabilizing device is characterized by further comprising an air inlet pipeline, a regulation and control assembly, a Venturi tube, a first flow monitor, a second flow monitor and a central control module; the air outlet end of the air inlet pipeline is communicated with the air inlet; the regulation and control assembly is arranged on the air inlet pipeline and located at the air inlet. The regulation and control assembly has a degree of freedom of moving in the radial direction of the air inlet pipeline and is used for opening and closing the air inlet; the venturi tube is coaxially arranged in the gas inlet pipeline; the first flow monitor is arranged at the air inlet end of the air inlet pipeline; the second flow monitor is arranged between the regulation and control assembly and the air inlet; the central control module is electrically connected with the first flow monitor, the second flow monitor and a power source of the regulation and control assembly. The method has the technical effects of automatically adjusting the air pressure before entering the compressor and prolonging the service life of the compressor.

The present application provides an electric gas compression device, having an air compressor main body device, the air compressor main body device comprising: a motor, including a stator, a rotor and a main shaft fixed to the rotor; a first-stage centrifugal air compressor, arranged on a first side of the motor axis, the first-stage centrifugal air compressor including a first-stage double-sided impeller arranged at a first end of the main shaft; a second-stage centrifugal air compressor, arranged on a second side of the motor axis, the second-stage centrifugal air compressor including a second-stage double-sided impeller arranged at a second end of the main shaft, the second-stage double-sided impeller is coaxially arranged with the first-stage double-sided impeller, and when the motor is working, the intake pressure on the front and back sides of the first-stage double-sided impeller is the same, and the intake pressure on the front and back sides of the second-stage double-sided impeller is also the same, so that the axial forces offset each other, the flow range is wide, the difficulty of bearing design is reduced, the reliability is improved, and a high-compact design of the whole machine is achieved.

The present invention discloses a closed-loop EGR flow control system and control method for a natural gas engine. The control system includes: a controller for determining an EGR demand flow rate based on actual engine operating conditions; a controller for obtaining the pressure of an air and gas mixture detected by an intake pressure sensor; or, alternatively, for determining the pressure of an air and gas mixture based on the EGR demand flow rate, a threshold flow rate, the maximum opening of an EGR valve, the actual opening of the EGR valve, the gas flow rate, and the fresh air flow rate; a controller for determining an actual EGR flow rate based on the obtained pressure of the air and gas mixture, the partial pressure of gases in the cylinder, the pressure-to-flow conversion slope, the gas flow rate, and the fresh air flow rate; a controller for determining an EGR flow rate correction value based on the obtained actual EGR flow rate and the EGR demand flow rate; and a controller for adjusting the EGR valve opening based on the EGR flow rate correction value so that the actual EGR flow rate matches the EGR demand flow rate, thereby achieving closed-loop control of the EGR flow rate. The present invention can achieve precise control of the EGR flow rate in two ways.

The invention discloses a method, a device and equipment for monitoring a vehicle-mounted air filter and a vehicle. The method comprises the following steps of: obtaining alarm pressure of an air inlet resistance sensor according to a theoretical life curve of the vehicle-mounted air filter; the state of the engine and the air inlet resistance measured by the air inlet resistance sensor are obtained in real time; and when it is detected that the engine is in the preset operation state, the air inlet resistance is larger than or equal to the alarm pressure and lasts for preset time, the vehicle is controlled to send out a first alarm signal. The vehicle-mounted air filter is monitored through the existing air inlet resistance sensor of the vehicle, other sensors and communication systems do not need to be added, the structure is simple, and cost is lower. The air inlet resistance measured by the air inlet resistance sensor is directly compared with the alarm pressure, only the air inlet resistance condition needs to be considered, factors such as the air quality and the air inlet amount do not need to be considered, the computational logic is relatively simpler, and the requirement for the operational capability of the ECU is low. The user can be accurately guided to maintain the air filter, and meanwhile, the user can reasonably plan the maintenance time, and normal work is prevented from being influenced.

The embodiment of the invention provides an engine supercharging system and a vehicle, and relates to the technical field of vehicle manufacturing. The electronic supercharger is constructed into a two-stage supercharger, the electronic supercharger is provided with a first-stage compressed air flow channel and a second-stage compressed air flow channel, a turbine compressed air flow channel is formed in the turbocharger, and the first-stage compressed air flow channel, the second-stage compressed air flow channel and the turbine compressed air flow channel are distributed in series. And the three-stage compressed air inlets are communicated with the air inlet to form three-stage compressed air inlet to the air inlet. According to the engine supercharging system provided by the embodiment of the invention, gas can be supercharged for three times through the first-stage compressed air flow channel, the second-stage compressed air flow channel and the turbine compressed air flow channel, so that the air compression ratio can be increased, the turbine hysteresis phenomenon is avoided, the air inlet pressure response speed is increased, and transient air supply to an engine is ensured; the operation stability and combustion efficiency of the engine are guaranteed, the fuel economy of the engine is improved, and the driving experience is improved.

The invention provides a low-temperature control method and system of a heat pump system, a storage medium and a vehicle. The method comprises the steps that after a whole vehicle is powered on, the water temperature of an electric drive outlet of an electric drive loop is obtained; when the water temperature of the electrically-driven outlet is lower than a first preset temperature threshold value, electrically-driven active heating is controlled to be started; when a passenger compartment heating request is received, the pressure of an air suction port of a compressor is obtained; and when the pressure of the air suction port is lower than the preset pressure threshold value, the compressor is controlled to enter a compressor pulse starting mode, and the compressor pulse starting mode is started in the mode that the compressor runs for the first duration at the preset low rotating speed and then stops to wait for the second duration. According to the invention, a PTC heater does not need to be additionally arranged, and the R134a heat pump system can be started and continuously and stably operated at the environment temperature of-30 DEG C or above.

The invention discloses an engine starting control method, device and equipment and a storage medium, relates to the technical field of engine control, and discloses an engine starting control method which comprises the steps that when an engine starting request is received, the engine starting water temperature and the environment pressure are obtained, based on the engine starting water temperature and the environment pressure, whether catalytic converter heating is activated or not is determined, and a catalytic converter heating activation result is obtained; the air inlet pressure and the engine rotating speed are obtained, and the air inlet flow and the starting ignition angle are determined based on at least one of the catalytic converter heating activation result, the engine starting water temperature, the air inlet pressure and the engine rotating speed; oil injection times and shutdown duration are obtained, and a starting target air-fuel ratio is determined based on the engine starting water temperature, the environment pressure, the oil injection times and the shutdown duration; and the engine is controlled to be started according to the air inlet flow, the starting ignition angle and the starting target air-fuel ratio. According to the scheme, the starting process of the engine can be accurately controlled, and efficient and safe starting of the engine is achieved.

The invention discloses a diaphragm compressor state monitoring method based on dynamic oil pressure and intake and exhaust pressure, and relates to the technical field of diaphragm compressors. The dynamic oil pressure of the compressor is monitored, the running state of the compressor is monitored according to the matching relation between the oil pressure and the air pressure, the fault is recognized in time, and even the fault is pre-judged, so that breakage of a diaphragm or overpressure in a cavity is avoided, and the loss caused by the fault of the compressor is reduced. The method comprises the following steps that S1, the set oil spill pressure of an overflow valve and the air inlet pressure and the exhaust pressure of a compressor are obtained; s2, according to the set oil spilling pressure, air inlet pressure and exhaust pressure, the oil pressure high reference and the oil pressure low reference of the running state of the diaphragm compressor are set; s3, measuring the running dynamic oil pressure of the compressor, and obtaining an oil pressure peak value and an oil pressure minimum value; and S4, the obtained oil pressure peak value and the obtained oil pressure minimum value are compared with the oil pressure high reference and the oil pressure low reference, and the running state of the compressor is judged according to the comparison result.

A partition plate is integrally formed between an acting side wall and a connecting boss, so that an air inlet area and an air outlet area which are located on the two sides of the partition plate and isolated from each other are formed in a rotor, and a plurality of supercharging fan blades are arranged in the air inlet area and used for centrifugal rotation to achieve air flow supercharging; the roots of the plurality of pressurizing fan blades are connected with the circumferential surface of the connecting boss and are arranged around the autorotation center at equal angles, so that gradually-expanded channels are formed among the pressurizing fan blades, a circle of confluence channels are arranged in the air inlet area along the inner side edge of the acting side wall, and the confluence channels are communicated with the gradually-expanded channels; the two sides of the rotor of the rotor engine are partitioned through the partition plates, normal air inlet and exhaust functions are guaranteed, the air inlet side of the rotor is provided with the supercharging fan blades rotating synchronously with the rotor, air in the air inlet area is entrained through rotation of the rotor, centrifugal supercharging airflow is formed through driving, the air inlet pressure is effectively increased, and then the air inlet amount of a combustion chamber is increased.

The invention discloses a control strategy for reducing engine oil consumption of an engine, and relates to the technical field of engines. The air inlet pressure in the engine cylinder is calculated by collecting the air inlet pressure behind the throttle valve and the local atmospheric pressure in real time, the air inlet pressure level in the cylinder can be accurately judged, whether the engine oil burning risk exists or not is recognized, when the negative pressure duration time in the engine cylinder exceeds the preset time threshold value, it is indicated that the engine oil burning risk exists, and the engine oil burning risk is judged. At the moment, the throttle valve is actively controlled to be opened, engine air inlet positive pressure is maintained, the situation that a large amount of engine oil flows upwards due to long-time negative pressure in an engine cylinder is reduced, and therefore engine oil burning faults of the engine are avoided.

The invention discloses a switch valve response time test system and method, and the method comprises the following steps: preparing test equipment which comprises an oscilloscope, a 24V DC power supply, a high-frequency response pressure sensor, a gas source, a gas storage tank, a pressure cylinder, a tested switch valve V0 and an auxiliary valve V4, and the switch valve V0 and the auxiliary valve V4 are connected in series; connecting a test system: fixing the tested switch valve V0 and the auxiliary valve V4 on a test board, and carrying out gas circuit connection; setting test parameters: setting initial pressure and target pressure through upper computer software; the air inlet pressure is set to be 3bar, and the pressure cylinder amplifies and outputs according to the proportion of 1: 2, so that the air outlet pressure reaches 6bar; the device has the beneficial effects that the structure is simple, the operation is convenient, and the test efficiency is improved; the air inlet pressure requirement is low, and the safety of the testing process is improved; and the auxiliary valve V4 is connected in series, so that the interference of the self response time on the test result of the switch valve V0 is eliminated, and the test precision is improved.

The invention discloses a gas station gas discharging system and a control method thereof.The gas station gas discharging system comprises a multi-stage compression cylinder, a hydraulic driving system with the fixed displacement, a gas storage device, a gas dispenser, an electric control valve set, a gas pressure detection unit and a control module, and the hydraulic driving system, the gas dispenser, the electric control valve set and the gas pressure detection unit are in communication connection with the control module; the gas storage device comprises a plurality of gas storage bottles with different target gas storage pressures; the electric control valve group comprises second electric control valves arranged on the gas storage pipelines and fourth electric control valves arranged on at least one oil port of the final-stage compression cylinder; and during gas discharging, the control module can control the second electric control valves on the gas storage pipelines to work according to a preset gas charging control strategy, and the opening and closing states of the fourth electric control valves are controlled according to the gas inlet pressure of the last but one stage of compression cylinder and the real-time gas storage pressure of the currently filled gas storage bottle. The gas discharging rate and the gas discharging efficiency of the gas discharging system of the gas filling station can be effectively improved.

The utility model discloses a gas saving secondary pressure reducing valve, which belongs to the technical field of valves, and comprises a pressure reducing valve body and a flow adjusting shell, an adapter is arranged between the pressure reducing valve body and the flow adjusting shell, a flow control adjusting mechanism is arranged on the flow adjusting shell, and an air inlet pressure gauge is fixedly arranged at the front part of the flow adjusting shell. According to the pressure reducing valve, the pressure of gas in the pressure reducing valve body is adjusted through the valve switch, the two protective shells are closed to be arranged on the outer side of the valve switch, the valve switch is extruded and fixed through the rubber block on the inner side of the valve switch, and meanwhile the outer side of the valve switch is protected; and a bolt is driven by the elastic force of a spring to be inserted into an insertion hole to fix the fixed seat and the L-shaped connecting seat, so that the two protective shells are fixed, the valve switch is protected and locked, a user is effectively prevented from randomly adjusting the pressure, and the practicability is good.

The present invention relates to the field of automotive control technology, and particularly to an engine control method, device, equipment and computer-readable storage medium. The engine control method includes: obtaining the concentration of nitrogen oxides in the original exhaust of the engine at least once through a NOx sensor installed upstream of the three-way catalytic converter, and obtaining the engine torque corresponding to the nitrogen oxide concentration; determining a fuel quality coefficient from a preset ignition control map based on the nitrogen oxide concentration and the engine torque; if the fuel quality coefficient is within a first preset range, controlling the intake pressure of the engine based on the fuel quality coefficient. The present invention realizes detecting the fuel quality in the engine before controlling the intake pressure of the engine, and controlling the intake pressure of the engine based on the fuel quality when the fuel quality is normal, so as to consider the interference of the fuel quality on the intake pressure during the process of controlling the intake pressure, improve the accuracy of controlling the intake pressure of the engine, and thus reduce the pollution of the engine exhaust gas.

The utility model relates to the field of air purification, and particularly discloses a high-flow low-pressure-difference small-size self-cleaning air filter which comprises a shell, a plate type filter element, a sealing element, a controller, a pressure difference switch, a bearing seat, a reciprocating screw rod, a chain wheel unit, a strip-shaped nozzle, an energy storage unit and a pressure guide hose, the two plate type filter elements are fixedly connected with the shell respectively, the two bearing seats are fixedly connected with the shell respectively, the two ends of the reciprocating screw rod are embedded into the corresponding bearing seats respectively, the two ends of the pressure guide hose are communicated with the strip-shaped nozzle and the output end of the energy storage unit respectively, the controller is fixedly connected with the shell, and the differential pressure switch is fixedly connected with the shell. And each group of sealing elements are respectively arranged on the peripheral side of the corresponding plate type filter element. The air filter element can be self-cleaned in the running process of equipment, and the air filter element has the advantages of being smaller in size, larger in air inlet amount, lower in air inlet pressure loss, higher in filtering precision and better in automation degree.

The invention relates to a hydrogen-diesel oil dual-fuel single-cylinder engine heavy-load working condition combustion control system and method, belongs to the technical field of engines, and is characterized in that an air inlet pressure sensor is mounted near an air inlet valve, a control valve is mounted in an air inlet channel, an electric supercharger and an intercooler are connected to the other air inlet channel in series, and a temperature sensor is mounted; a pressure sensor, a hydrogen sprayer and an oil sprayer are installed in the combustion chamber, and the hydrogen sprayer, the oil sprayer, the electric supercharger, the control valve, the air inlet pressure sensor, the pressure sensor, the intercooler and the temperature sensor are connected with a vehicle-mounted computer at the same time. The control over the pressure rising rate and the pressure fluctuation of the hydrogen-diesel oil dual-fuel single-cylinder engine under the large-load working condition is achieved by adjusting the air inlet supercharging pressure and the fuel injection control strategy, and the problem of abnormal combustion under the large-load working condition is solved.

The invention discloses an automobile engine multi-sensor fault diagnosis system and method, and particularly relates to the technical field of engine multi-sensor fault diagnosis, the automobile engine multi-sensor fault diagnosis system comprises a plurality of sensors, a diagnosis module and a calibration module, the plurality of sensors collect engine operation data and cover air inlet pressure sensors, boost pressure sensors and the like; the diagnosis module diagnoses sensor faults according to preset enabling conditions and logic description, wherein the sensor faults comprise various types of power supply short circuit, ground short circuit and the like; the calibration module sets calibration parameters and verifies and adjusts the parameters in three-high tests and daily calibration. The system and the method can comprehensively diagnose sensor faults, improve diagnosis accuracy and reliability, adapt to different working condition environments, guarantee normal operation of an engine, improve driving experience and stability of an automobile electrical system, and have remarkable practical value.

The invention relates to the technical field of wall-hanging stoves, and discloses an ignition control method and device of a wall-hanging stove, a controller and the wall-hanging stove.The ignition control method comprises the steps that when ignition of the wall-hanging stove fails, the valve opening current of a gas proportional valve of the wall-hanging stove is detected, and when the valve opening current is smaller than a preset current threshold value, the valve opening current is increased, and the wall-hanging stove is controlled to execute ignition operation again; when the valve opening current is larger than or equal to the preset current threshold value, the fan rotating speed of the wall-hanging stove is detected; and when the rotating speed of the fan is larger than the preset rotating speed threshold value, the rotating speed of the fan is adjusted to the preset rotating speed threshold value, and the wall-hanging stove is controlled to execute re-ignition operation. According to the method, the valve opening current is firstly adjusted when the execution of the ignition operation fails, so that the ignition success rate of the wall-hanging stove is increased by increasing the air inlet pressure, and the rotating speed of the fan is adjusted when the valve opening current is greater than the preset current threshold value, so that the ignition failure caused by flame separation and fire transfer failure is avoided by reducing the air inlet amount of cold air; the ignition success rate of the wall-hanging stove is improved.

The present disclosure provides a vehicle leak detection apparatus with automatic intake pressure regulation, comprising: an air pump; a first pipeline configured to allow air pumped by the air pump to be pumped into a test vehicle; a smoke generation unit arranged between the air pump and the test vehicle and configured to generate visible smoke in the air pumped into the test vehicle; and a check valve removably connected to the first pipeline and configured to release air after an air pressure in the first pipeline exceeds an intake pressure that the check valve can withstand so as to automatically regulate the intake pressure during vehicle leak detection.

The invention discloses a hydrogen engine crankcase hydrogen concentration control method, and relates to the field of hydrogen engines, and the method comprises the steps: placing a hydrogen engine on a rack for testing, and obtaining a target hydrogen concentration, an actually measured hydrogen concentration and a crankcase blow-by amount; according to the target hydrogen concentration, the actually measured hydrogen concentration and the crankcase blow-by amount, the target working condition supplementary air amount is calculated; according to the target working condition supplementary air amount, a full-working-condition supplementary air amount database is generated based on the rotating speeds and loads of the different working conditions; obtaining the amount of fresh air needing to be supplemented under the current target working condition according to the full-working-condition air supplementing amount database; the air inlet pressure, the air inlet temperature and the crankcase pressure are obtained; the method comprises the following steps: calculating the opening degree of a throttle valve by combining the air inlet pressure, the air inlet temperature and the crankcase pressure, comparing the hydrogen concentration measured by a hydrogen concentration sensor according to the current target working condition with the target hydrogen concentration to obtain a hydrogen concentration deviation and generate a corrected fresh air amount, and carrying out closed-loop control on the actual crankcase hydrogen concentration by adjusting the opening degree of the throttle valve.

The invention relates to an air pressure test system and method, and the system comprises an inflation unit which is used for providing high-pressure air for a target chamber and is sequentially connected with an air source cylinder, a first pressure regulating device, a booster pump, a flowmeter and a second pressure regulating device, and the first pressure regulating device is used for regulating the air inlet pressure entering the booster pump; the booster pump is used for boosting gas pressure to meet the pressurizing requirement; the flow meter and the second pressure regulating device are used for regulating the flow pressure of gas entering the target chamber; the operation gas supply unit comprises an operation gas cylinder and a third pressure regulating device, is connected to the booster pump and is used for providing operation gas for the booster pump and controlling the pressurization rate; the control unit comprises a PLC (Programmable Logic Controller) control module and an upper computer, is in signal connection with each pressure regulating device, the flow meter and the booster pump, and is used for automatically regulating each component; and the pressure relief protection unit comprises a pressure relief device and is used for releasing the gas pressure of the target chamber when the gas pressure test is finished. The device is convenient to operate, high in automation degree and comprehensive in protection measures, and the test efficiency and the operation safety and convenience are improved.

The present invention relates to the field of casting technology, and specifically to a compaction control system and method for compaction molding on a compaction table, wherein the method comprises: S1, a control module scans mold information, and matches corresponding compaction parameters according to the mold information; S2, a sand mixing device is started to fill the mold with sand, and the weight of the sand is obtained after the sand filling is completed; S3, the optimal vibration motor data and the optimal spring intake pressure of the air spring are matched according to the sand weight; S4, the compaction table is started to complete the compaction molding. The present invention matches the corresponding compaction parameters according to the mold information, and at the same time matches the optimal vibration motor data and the optimal spring intake pressure of the air spring according to the sand weight, which can well reduce the air retained in the sand, reduce the gaps between the sand, and solve the technical problem of large compaction differences after compaction in the prior art.