187 results about "Heat current" patented technology

An electrochemical cell having a current interrupting switch as an internal component of the cell that is thermally responsive and breaks an electrical path within the cell thereby preventing current flow when temperature within the cell is at or above an activating temperature. The switch is reversible and current flow and a closed circuit is re-established when temperature within the cell returns below the activating temperature.

In a DC-DC converter, the cooling of switching elements has been performed only by means of a cooling plate; therefore, there is a problem in that, to effectively radiate heats generated by power MOSFETs that have large heating values and that are arranged parallel, it becomes necessary to reduce thermal resistances and complicate the cooling route of a water-cooling device. Plural switching elements for controlling currents flowing through inductor elements, which are used for voltage conversion of a DC-DC converter, are fixed to a metal case via a heat conductive insulating material and via a metal radiator having a better heat conduction characteristic than the metal case. Because there occur no large mixing phenomena of heat currents among neighboring switching elements, and there are only little heat interferences between the neighboring switching elements, the thermal diffusion characteristic is improved, and the cooling efficiency for the switching elements can be increased.

The invention discloses a multi-function sensor and a heat current and temperature measuring method under high temperature, wherein the multi-function sensor comprises a shell and a heat current measuring head, the heat current measuring head is arranged on the shell and comprises a heat current probe and a heat sink, the heat sink and the heat current probe are connected and holded in the shell to form a thermoelectric couple with the heat current probe, a cooling device used for cooling the heat current measuring head and another thermoelectric couple used for measuring the temperature of the heat sink are also arranged in the shell, the two thermoelectric couples are connected with a surveymeter, and the detection of heat current and temperature is realized by measuring the voltage signal of the two thermoelectric couples. In the measuring method disclosed by the invention, a mathematical model is built to derive and obtain high temperature to be measured by measuring low temperature. The multi-function sensor of the invention can measure heat current and temperature in high temperature environment, overcomes the problem that temperature can not be measured under high temperature environment when the original thermoelectric couple is more than 2000K; not only can the heat current be measured, but also the thermoelectric couple can be ensured to work under high temperature environment, thus the temperature is effectively measured.

The invention discloses a full digital temperature controller applied to optical fiber gyroscope inertia measurement combination, comprising seven temperature sensors, one DSP processor, two photoelectric coupler, seven-channel switch power amplifier and power supply circuit, where the DSP processor compares eN=TN-tn to control PWM wave generation, where tn is working temperature collected real-timely by temperature sensor and TN is set temperature, so as to drive heating component to make automatic adjustment control of heating current, which forms a closed-loop feedback device. And the invention controls working temperatures of the heating component and the controlled object, making them work at constant temperature, thus overcoming the effect of environmental temperature change on output accuracy of inertia components.

A capacitive sensing system for being connected to a heating element comprises a capacitive detector connectable to the heating element and a common mode choke for essentially preventing alternating current from flowing from the heating element to the heating current supply. The capacitive detector is configured for driving an alternating current into the heating element and for producing an output indicative of capacitance based upon the alternating current. The choke has a first and a second winding for connecting the heating element with the heating current supply. The choke comprises a third winding connected in parallel of the first and/or second winding. The capacitive detector is configured for measuring a portion of the alternating current flowing across the third winding and for taking into account the measured portion of alternating current when producing the output.

The invention discloses a differential scanning calorimeter, which is compatible with visualization and comprises a worktable, a first heat current detection part, a second heat current detection part, temperature control equipment, a temperature-recording instrument, a microscope image pickup system and an image acquisition system; wherein, the worktable is provided with a sample cell and a reference cell. The first heat current detection part is arranged in the sample cell and used for bearing samples and transmitting heat flux with the samples. The second heat current detection part is arranged in the reference cell and is used for bearing reference compound and transmitting heat flux with the reference compound. The temperate control equipment respectively controls the heating up and temperature reduction of the two heat current detection parts. The temperature-recording instrument is respectively connected with the two heat current detection parts by a thermocouple wire. The microscope image pickup system observes the microstructure of the samples by a sample observation window arranged on the sample cell and acquires and records the microstructure variation of the sample by the image acquisition system. The differential scanning calorimeter can monitor and acquires the structure variation information of the sample while measuring the heat flow when the samples change phase, and increases the synchronicity and integrity of real-time analysis detecting of the samples.

The invention provides a multi-IGBT quick power circulation accelerated aging device, and the device comprises a plurality of IGBT device aging stations, a heating current source for testing, and a testing current source for testing. The IGBT device aging stations are sequentially connected to form a series structure. The heating current source and the testing current source alternately supply power to the IGBT device aging stations in series connection. The device can achieve the aging testing of a plurality of IGBT devices at the same time, just needs one heating current source and one testing current source, guarantees the homogeneity of testing currents during testing, improves the work efficiency, irons out the defects of testing data in the prior art, greatly improves the accuracy of testing data, guarantees the comparability of the testing data, and guarantees the stability and accuracy of the final testing analysis results of the IGBT devices.

One embodiment of a thermal interface material includes a plurality of carbon nanotubes each having a first end and an opposite second end, a heat current collector covering one of the first ends and the second ends of the carbon nanotubes, and a macromolecular material filled in spaces between the carbon nanotubes and heat current collector. A method for manufacturing a thermal interface material is also provided.

An electric heater includes a casing having a receiving compartment and an air outlet communicating the receiving compartment to outside and a plurality of radiant conductive fins spacedly supported in the receiving compartment to define an air heating channel between each two radiant conductive fins, wherein each of the radiant conductive fins has at least a guiding slot formed thereon. A heating element is electrically connected to a power source wherein the heating element is transversely extended to the radiant conductive fins through the guiding slots to heat up the radiant conductive fins in such a manner when the radiant conductive fins are heated up for warming an air within the air heating channels, a heat current is created on each radiant conductive fin for creating heat flows flowing from the air heating channels respectively to outside through the air outlet.

The invention relates to a preheating system for an automobile engine and a controlling method for the preheating system. The preheating system comprises a mobile terminal, a vehicle-mounted controller, an engine control module, a storage battery, an electrical quantity sensor, a cooling liquid sensor, a preheating control module, a heating oil injector and a preheating feedback module, wherein the vehicle-mounted controller can recognize a preheating signal of the mobile terminal; the engine control module detects a feedback signal of the cooling liquid sensor, and transfers the feedback signal to the preheating control module; the preheating control module controls the storage battery to provide power for the heating oil injector; the preheating feedback module transfers the received signal to the mobile terminal. According to the invention, preheating can be conducted when a driver does not enter an automobile; meanwhile, the temperature of the engine can be detected accurately; heating current is controlled according to the temperature; electrical energy is saved; starting waiting time is saved; the start speed of the automobile is improved.

A system and method is provided. The system includes a high intensity energy source to create a molten puddle on a surface of a workpiece and a wire feeder that feeds a wire to the molten puddle via a contact tube. The system also includes a power supply that outputs a first heating current during a first mode of operation and a second heating current during a second mode of operation. The system further includes a controller that initiates the first mode of operation in the power supply to heat the wire to a desired temperature and switches the power supply from the first mode of operation to the second mode of operation to create a micro-arc. The second mode of operation provides at least one of an increased heat input to the molten puddle and an increased agitation of the molten puddle relative to the first mode of operation.

A capacitive sensor configured for connection between a heating element and a heating current supply comprises a common mode choke (CMC) for AC-decoupling the heating element from the heating current supply. The CMC comprises first and second inductively coupled windings, the first winding for connection between a first terminal of the heating current supply and a first terminal of the heating element and the second winding for connection between a second terminal of the heating element and a second terminal of the heating current supply. The capacitive sensor further comprises a control and evaluation circuit for injecting an AC signal into the heating element via a measurement node, measuring a voltage on and/or a current across the measurement node, and to derive an impedance between the heating element and a counter electrode from the measurement. The CMC comprises a third winding inductively coupled with the first and second windings, the third winding being operatively coupled with the measurement node.

The electric upsetter includes mechanical mechanism, heating mechanism, detection mechanism, and control mechanism. The mechanical mechanism includes upsetting cylinder, upsetting block, smithy cylinder, smithy block and conducting holding cylinder; the heating mechanism includes holding electrodes and transformer; the detection mechanism includes displacements mounted on the upsetting cylinder and the smithy cylinder separately; and the transformer is controlled with an electronic unit and continuously controlled output voltage. Based on the plastic mechanics and thermodynamic principles, the calculation method of heating current, upsetting pressure, speed and other technological parameters is given; and by means of the continuous closed loop control of speed, pressure, temperature and current, the optimal control of the electric upsetting process is realized.

An electronic device includes a circuit board and a heat insulating structure. The heat insulating structure includes a heat source, an enclosure for covering the heat source, and a heat insulating plate disposed on a side of the enclosure facing to the heat source for preventing heat generated by the heat source from directly transmitting toward the enclosure, and a space being formed between the heat insulating plate and the enclosure. The heat insulating structure further includes a thermal conductive layer disposed on a side of the heat insulating plate facing to the heat source. The heat insulating structure further includes the thermal conductive layer disposed on a side of the heat insulating plate facing to the enclosure. Therefore, the heat insulating plate can be for altering heat current generated by the heat source so as to dissipate the heat current via holes on the enclosure uniformly.

The invention provides a fault current composite test method for a high-voltage direct current power transmission converter valve. According to the method, a rectification current source supplies heating current to a test sample valve Vt before supplying fault current; and the fault current is supplied to the test sample valve Vt by using a mode of compositing short circuit current of a direct current source and discharge current of an additional power supply. By the technical scheme, the short circuit current of a heating current source is utilized fully, so that the designed maximum output current value of the additional fault current source is reduced, the utilization efficiency of a test circuit is improved, the cost is saved, and the fault current can be adjusted in a large range; and furthermore, a test requirement on the fault current of the converter valves in the conventional high-voltage direct current engineering and the extra-high-voltage direct current engineering can be met, and the method is high in generality.

The invention relates to a micro heat flow gyroscope, adopting the two-way fluid shunt channel structure, which generates two fluids with the completely same speed and temperature and the opposite speed direction through the periodic alternative change of volume of a driving membrane vibration deformation control chamber; the fluids respectively flow through their own cushion chamber and main micro-flow channel, shunt to the symmetrically arranged shunt channel with a thermosensitive device, the convective heat transfer between the thermosensitive device and the fluid comprises angular velocity information, and the angular velocity is gained through detecting the temperature difference of two pairs of symmetrically arranged thermosensitive devices. The invention has the advantages of effectively reducing the negative influence of centrifugal force coupling on detection precision, simultaneously optimizing the detection precision and range, being applied to the occasion of uniform angular velocity and non-uniform angular velocity, and having the simple structure and the high sensitivity and resolution.

The invention discloses a method and device for heating a compressor through a stator winding. The method comprises the following steps that S10, the outdoor temperature is acquired through a temperature sensor; S11, a main control module determines the heating current according to the acquired outdoor temperature and sends a heating current adjustment instruction to a frequency converter; and S12, the frequency converter receives the control instruction and controls PWM waves to generate corresponding current to heat the compressor through a vector control method. According to the method anddevice for heating the compressor through the stator winding, the vector control method is used for heating the compressor, so that the heating reliability and stability of the compressor of a commercial air conditioner are improved; and meanwhile, the heating control precision is improved, energy consumption is reduced, and the cost is reduced.

The invention provides a piston temperature field simulation test device. The device comprises cooling equipment, a thermocouple temperature acquiring machine, a piston, an induction heater and high-frequency induction heating equipment; the induction heater can heat the head part of the piston, meanwhile, the piston is fixed into the cooling equipment, the cooling equipment is provided with a plurality of air cavities which are used for cooling the areas with the piston feature points, the cooling capability of the cooling equipment can be controlled by adjusting an electric air volume adjusting valve, and accordingly a needed piston temperature field module is obtained. The top face of the piston and the induction heater are maintained at the optimal induction heating distance through transverse and longitudinal movement of the cooling equipment, and maximum heat current input is ensured. Corresponding temperature measuring points are arranged in the piston feature areas, and temperature acquiring information is monitored by the thermocouple temperature acquiring machine. The test method adopts a thermocouple method to test the temperature field of the piston. The piston temperature field simulation test device and the test method have the advantages that the heat current is input stably, the position of the piston is adjusted, the heat current distribution module of the piston can be precisely simulated, and multi-point measuring can be achieved.

A one-dimensional evaluation method of combustion efficiency for scramjet engine relate to an evaluation method of combustion efficiency for engine. The method realizes quick evaluation for economic performance in combustion condition; and the application range of the existing one-dimensional evaluation method is enlarged so as to have universality. The method has the following steps: the entry condition and pressure distribution are ensured; the initial value eta0 of combustion efficiency is given; each component mass fraction g at the section of combustion chamber is ensured; the combustion mixture temperature Tkc is ensured; the combustion mixture enthalpy value Hkc and average molecular weight mukc are calculated; the local sound velocity a and mach number M at the section of combustion chamber are calculated; the friction coefficient cf at the wall surface of combustion chamber and the dissipative force X0 along flow direction are ensured; the combustion mixture flow speed velocity w, the heat current qw at the wall surface of combustion chamber and the calculated value eta of combustion efficiency are calculated; and whether the combustion efficiency is the same as the initial value is judged. The application of the method can quickly analyze ultrasonic speed combustion efficiency and related thermal and pneumatic parameters, and finally obtains one-dimensional distribution rule of combustion efficiency and related parameters along axial direction of combustion chamber.

The invention discloses a microsatellite driving heat controlling system based on LHP passive heat elimination, which comprises a heat current temperature data processing module and an active heat controlling device, wherein the active heat controlling device has the structure that an LHP return flow channel and an LHP steam channel are respectively arranged between an LHP condenser and an LHP evaporator, a heat flow sensor is bonded between a heating device and the LHP evaporator, a temperature sensor A is arranged on the heating device, the LHP condenser is arranged on the inner surface of a radiating surface radiator, the outer surface of the radiating surface radiator is provided with grooves A and B, and temperature sensors are respectively arranged in the grooves A and B; the heat current temperature data processing module comprises a temperature channel deviation generating unit, a heat current channel deviation generating unit, a two-channel deviation signal fusing unit and a heat current and temperature control converting unit. The driving heat controlling system realizes the two-channel data fusion of the temperature and the heat current,, increases the response speed of the heat controlling system of the microsatellite, eliminates the frequent vibration of a heat control shutter, and prolongs the service life of the mechanical structure of the heat control shutter under the premise that the good steady-state performance of the heat controlling system is ensured.

The invention discloses a heat exchanger using a microporous hydrophobic membrane for strengthening heat exchange. The shell of the heat exchanger is made of metal and fluid in the internal pipeline in the heat exchanger is divided by the microporous hydrophobic membrane into two parts flowing in opposite directions; fluid on a hot side of the heat exchanger contacts a heat exchange surface; the fluid on the hot side is heated by an external heat current, the temperature of the fluid on the hot side rises to generate a vapor pressure difference between two sides of the membrane, a working medium on high vapor pressure side evaporates and penetrates the membrane to flow to a low pressure side to achieve an effect of phase change heat transfer.

The invention relates to the technical field of electric heating metal powder sintering, in particular to a powder sintering molding method and mold. According to the method, a powder material is contained in a concave mold, heating current is input, the powder material is extruded under the condition of preventing the concave mold from shunting the heating current, and the powder material is subjected to sintering molding under pressure. Due to the fact that the heating current is input to the powder material under the condition of preventing the concave mold from shunting the heating current, the current density of the powder material can be increased, and the power load can be reduced; and in addition, the size of the concave mold is far larger than that of the powder material, and therefore after the current shunting function of the concave mold is eradicated, the heating effect of the powder material can be optimized to a large degree.