605 results about "Thermal circuit" patented technology

The present invention provides a steam injection heatpump heating system. The technical solution is that the system is composed of a steam injector, a high voltage steam pipeline, a low voltage steam pipeline, a throttling gear and a bypass connecting pipe. The high voltage steam enters in the heat exchanger heaing backwater after injecting lower steam turbine voltage condensing in low temperature, this realises waste heat recovery in low temperature condensing steam of the steam turbine. The core component is the steam injector, the high voltage heat supplying pumping is used as high-velocity jet acceleratively formed in the injecting tube of the working steam, and lower voltage steam turbine is rolled in the mixing room as injected flow, mixing steam in the expanding section of the steam injector is decelerately compressed in a certain back pressure, then sending to the heat interchanger for heating backwater, a certian back pressure mixing steam condenses to water after heat releasing in the exchanger, returning to the backwater system of electrical factory, completing thermal circuit of the combined heat and power generation set.

The invention relates to a thermal management system for a lamp. The system comprises a lamp socket that comprises a socket body. The thermal assembly is in thermal communication with the socket body to form a thermal circuit between the lamp and the thermal assembly for dissipating heat generated by the lamp.

The present invention concerns a compact, multi-purpose magneto-calorific thermal generator of high thermal efficiency, having a maximal heat exchange coefficient, while being simple to industrialise in order to respond to a wide range of both industrial and domestic applications.

The thermal generator (1) is characterised in that it comprises at least one thermal module (10) constituted from many thermal elements (40), stacked and arranged in order to delimit between each other channels for the circulation of heat transfer fluid, these channels being divided into hot channels in which the heat transfer fluid of the hot circuit flows and cold channels in which the heat transfer fluid of the cold circuit flows, the hot and cold channels being alternated between the said thermal elements (40) and in that the said thermal elements have fluid inlet and outlet orifices which communicate with each other so as to distribute the flow of heat transfer fluid of each hot and cold collector circuit respectively in the corresponding hot and cold channels.

Applications: Heating, tempering, air conditioning or refrigeration in any industrial or domestic installation.

Systems and methods are provided for heating a fluid comprising an opened-loop heating circuit or a closed-loop heating circuit both comprising a rotary heating device, such as a water brake, and a closed-loop direct-fired boiler heating circuit; and systems and methods for evaporating a fluid and systems and methods for concentrating a fluid based on these heating circuits.

A conductive adapter for carrying relatively high current from a source to an external circuit without degradation is provided. The adapter includes a conducting member made from a conductive nanostructure-based material and having opposing ends. The adapter can also include a connector portion positioned on one end of the conducting member for maximizing a number of conductive nanostructures within the conducting member in contact with connector portion, so as to enable efficient conduction between a nanoscale environment and a traditional electrical and/or thermal circuit system. The adapter can further include a coupling mechanism situated between the conducting member and the connector portion, to provide a substantially uniform contact between the conductive nanostructure-based material in the conducting member and the connector portion. A method for making such a conductive adapter is also provided.

The invention discloses a method for calculating the conductor temperature of a cable. The method comprises the following steps: calculating a relation expression between a calculated value of the conductor temperature of the cable in a steady state and a heat-conductivity coefficient of a structural material of each layer of the cable by using a thermal-circuit method; calculating a functional relation between the heat-conductivity coefficient of the structural material of each layer of the cable and a corresponding sensitivity by using a sensitivity principle, and calculating the value of a sensitivity corresponding to the heat-conductivity coefficient of the structural material of each layer of the cable according to the functional relation; and adjusting the value of a selected heat-conductivity coefficient according to the value of the sensitivity, then calculating the conductor temperature of the cable according to the adjusted value of the heat-conductivity coefficient. The invention also provides a device for calculating the conductor temperature of the cable. By using the technology of the invention, the conductor temperature can be calculated accurately and the current-carrying capacity of the cable can be assessed accurately; and the calculated value of the conductor temperature of the cable is significantly improved on the basis of a calculated value stipulated in IEC (international electrotechnical commission) standards, thereby avoiding the occurrence of a problem that a result of the conductor temperature of the cable, calculated according to the IEC standards, has an excessive margin and a large error; and the method and device disclosed by the invention provide references for the real-time monitoring of the cable and the improvement of transmission capacity and operation of the cable.

The invention discloses a predication method and device for top-oil temperature of a transformer based on error predicting amendment, pertaining to the on-line monitoring field of the transformer. The method comprises following steps: obtaining a prediction dataset comprising load current and ambient environment of the transformer; using load current of the transformer at the current moment as input amount, utilizing a Susa thermal circuit model to predict top-oil temperature of the transformer in order to obtain top-oil temperature prediction value of the Susa thermal circuit model; normalizing top-oil temperature prediction value of the Susa thermal circuit model and the prediction dataset; using the normalized top-oil temperature prediction value of the Susa thermal circuit model and the prediction dataset as input amount and utilizing a GA-KEDLM model to make a regression forecast to obtain prediction errors; carry out anti-normalization operation on regression prediction errors; using prediction value of top-oil temperature of the Susa thermal circuit model before normalization to delete the regression prediction errors after anti-normalization operation in order to obtain top-oil temperature prediction value corrected by the transformer. The predication method and device for top-oil temperature of the transformer based on error predicting amendment are capable of accurately predicting top-oil temperature of the transformer.

The invention provides a cable-joint cable core temperature inversion method and a cable-joint cable core temperature inversion system on the basis of a surface temperature of a cable. The cable-joint cable core temperature inversion method comprises the following steps: S1, carrying out radial temperature inversion according to a cable one-dimensional transient thermal circuit model and a temperature of a surface temperature measured point of a cable body so as to obtain an inversion transient temperature of a cable core fit point; S2, constructing a cable two-dimensional temperature field simulation module by adopting a finite element temperature field simulation method and simulating transient temperatures of a cable core contact point and the cable core fit point under different loading currents and at different moments so as to obtain a transient temperature simulated data set; S3, using the transient temperature of the cable core contact point as an independent variable, using the transient temperature of the cable core fit point as a dependent variable and carrying out fitting on the transient temperature simulated data set so as to obtain a cable core axial temperature function; S4, combining the inversion transient temperature of the cable core fit point with the cable core axial temperature function to obtain a temperature of the cable core contact point. According to the invention, the accurate temperature of the cable core contact point can be obtained by utilizing the surface temperature of the cable body through inversion and fitting; the cable-joint cable core temperature inversion method and the cable-joint cable core temperature inversion system are simple, convenient and rapid.

Heat transfer systems are presented with improved heat dissipation schemes based upon an asymmetric arrangement of Peltier elements to form a hot side of greater area than the cold side. This permits greater heat dissipation at the hot side of the heat transfer device into a suitable heat sink. A substantially planar system of radial symmetry is the basis of a highly efficient heat spreading scheme. The ‘spokes’ of the system are pie-wedge shaped Peltier semiconductor elements having a small heat transfer junction at one end and large heat transfer junction at the other. In best versions, a concentric ring scheme has a cooled area at the center and a heat dump at the periphery. Semiconductor Peltier elements connect the two and provide a vehicle to carry heat radially away from a heat point source thermally coupled to the heat transfer system at an active area. These special arrangements are provided while still maintaining the necessary serial electronic circuit and parallel thermal circuit.

This invention provides a compensation system capable of compensating for power loss due to the power compression effects of the voice coil as the temperature of the voice coil increases. To compensate for the power compression effect, the invention predicts or estimates the temperature of the voice coil using a thermal-model, and adjusts the estimated temperature according to the cooling effect as the voice coil moves back and forth in the air gap. The thermal-model may be an equivalent electrical circuit that models the thermal circuit of a loudspeaker. With the input signal equating to the voltage delivered to the loudspeaker, the thermal-model estimates a temperature of the voice coil. The estimated temperature is then used to modify equalization parameters. To account for the cooling effect of the moving voice coil, the thermal resistance values may be modified dynamically, but since this cooling effect changes with frequency, a cooling equalization filter may be used to spectrally shape the cooling signal, whose RMS level may be used to modify the thermal resistance values. The invention may include a thermal limiter that determines whether the estimated voice coil temperature is below a predetermined maximum temperature to prevent overheating and possible destruction of the voice coil.

The invention discloses a 10kV three-core cable temperature field model establishing method. The method includes the steps that 1, thermal field simulation is conducted on a 10 kV three-core cable loaded with current through ANSYS simulation software, and a temperature field distribution diagram of a cable radial section is obtained; 2, the cable section is cut through a cutting method in cooperation with a cable symmetrical structure and the isotherm, the cable is equally cut into three parts according to three cable cores, and one of the three parts is selected to serve as the research object; 3, a steady state thermal circuit model is established for the selected one-third cable structure, and cable structure layers located on the isotherm on the same diagram serve as joints in the thermal circuit model; 4, the thermal resistance generated when heat flow flows through all layers of cable materials and the generated losses are determined; 5, the 10 kV three-core cable steady state thermal circuit model is established according to the temperature field distribution diagram of the 10 kV three-core cable, all the joints in the determined thermal circuit model, the heat resistance among all the joints and the losses of various materials. The established 10kV three-core cable steady state thermal circuit model can be used for numerical calculation.

The invention discloses a method for calculating the real-time conductor temperature of a three-core cable. The method comprises the following steps of: (1) simplifying a complete transient-state thermal circuit model of the three-core cable into the simplest transient-state thermal circuit model only containing an equivalent thermal capacitance and an equivalent thermal resistance; (2) only considering current changes and skin temperature changes to obtain the relationship among the temperature of a conductor, a load current and a skin temperature, thus obtaining the temperature rise of the conductor caused by only considering current changes and skin temperature changes due to analogy on a first-order circuit transient response; (3) calculating the generated steady-state temperature rise and a temperature rise caused by medium losses according to a current at an initial time; (4) calculating a temperature rise caused by n times of currents and skin temperature changes in two hours (a cable thermal time constant) from the initial time; (5) summating the skin temperature at the initial time and all the temperature rises above to obtain the conductor temperature of the three-core cable currently.

The invention discloses a method for calculating power cable real-time emergency carrying capacity. The method includes the steps of firstly, establishing a cable system transient state thermal circuit model; secondly, establishing a heat balance equation; thirdly, obtaining a general solution of the heat balance equation; fourthly, obtaining the expression of the temperature of a conductor according to the initial condition; fifthly, converting the expression of the temperature of the conductor into the expression of the real-time emergency carrying capacity; sixthly, measuring or calculating the environment temperature and the temperature of the conductor at the initial moment; seventhly, determining the time of the N-1 fault repairing period or the time of the peak electricity consumption period and the limit value of the temperature of the cable conductor; eighthly, calculating real-time emergency carrying capacity of a cable. The method has the advantages that the maximum carrying capacity, namely, the real-time emergency carrying capacity, which enables the temperature of the cable conductor to rise to the limit value in a certain period of time is calculated, the scientific and reasonable decision foundation is provided for power grid dispatch and power line repairing in the emergency situation, and the calculation can be easily and conveniently conducted.

The invention discloses a method for calculating hotspot temperatures of split type cooling transformers in underground substations. The method comprises the following steps of: obtaining equipment parameters of a split type cooling system transformer; carrying out a no-load test and a load test on the split type transformer and respectively carrying out measurements to obtain no-load loss and load loss of the transformer; carrying out a rated load temperature rise test to obtain rated top-layer oil temperature rise and winding temperature rise; establishing a split type transformer thermal circuit model on the basis of a thermoelectric equivalence theory, and optimizing the split type transformer thermal circuit model to obtain a transformer top-layer oil temperature thermal circuit model and a hotspot temperature model; and solving a thermal circuit differential equation by adoption of a four-order Ronge-Kutta method, and calculating a top-layer oil temperature time series and a hotspot temperature time series under a given load curve and a given environment temperature curve. According to the method disclosed by the invention, dynamic load capacity of the split type cooling transformers can be utilized more sufficiently to promote the good application of the transformers to online information monitoring.

The invention belongs to the technical field of vehicle battery heat dissipation, and discloses an automobile fuel cell cold start control system and method, and the system comprises an air compressor, an intercooler, a humidifier, a fuel cell stack, a water pump, a three-way control valve, a heater, a radiator, a throttle valve, a first valve, a second valve, a third valve, and a controller. An air heating path is formed by the air compressor, the intercooler, the humidifier, the fuel cell stack, the humidifier and the throttle valve; the water pump, three-way control valve, the heater, the intercooler, the second valve, the fuel cell stack, and the water pump form a cooling liquid heating loop; the water pump, the three-way valve, the radiator, the third valve, the fuel cell stack, and the water pump forms a first cooling liquid radiating loop; the water pump, the three-way control valve, the radiator, the first valve, and the water pump form a second cooling liquid radiating loop. Under a low-temperature condition, the fuel cell can be rapidly started under the low-temperature condition; under the condition of high temperature, the intercooler and the fuel cell stack are cooled by one radiator.

The invention discloses a method for predicting the hot-spot temperature of a transformer winding under low temperature, and the method comprises the steps: firstly building an improved three-thermal-circuit model; carrying out the correction of the improved three-thermal-circuit model in different oil flow cooling modes; comparing a temperature rise value, detected by a temperature measurement sensor, of transformer oil with a temperature value calculated through the corrected three-thermal-circuit model, and correcting a transformer thermal circuit model approaching to the reality; calculating the mean oil temperature of a transformer based on environment temperature through the transformer thermal circuit model approaching to the reality, enabling the mean oil temperature of the transformer to serve as the reference temperature of central oil temperature of the improved three-thermal-circuit model, calculating the top oil temperature of the model, and finally calculating the hot-spot temperature value of the transformer winding. According to the invention, the method is simple in design, is easy to implement, is easy to popularize and implement, provides a basis for the checking of the capability of a transformer for resisting a short-circuit fault, improves the operation safety and stability of the transformer, and is better in economic benefits.

The invention discloses an internal temperature on-line monitoring method of a traction transformer of V/X connection. The method comprises the following steps of: (1) acquiring the basic parameters of the transformer; (2) monitoring the current of a traction winding, the current of a positive feed winding and the temperature of top oil of the transformer on line and uploading the monitored data to an upper computer; and (3) calculating the on-line monitored data by utilizing an internal temperature rise calculating formula established on the basis of an internal temperature rise thermal circuit model of the traction transformer of V/X connection to obtain the internal temperature rise condition during the running of the traction transformer of V/X connection. The invention particularly aims at the traction transformers of V/X connection, which are widely applied to heavy haul railways and high speed railways in China at present, has the advantages of simple system structure, less data required to be monitored, easy monitoring, simple data processing process and lower requirement for computer performance; and an ordinary industrial personal computer can meet the requirement for operation, thus the calculating precision is higher.

The invention discloses a steady state thermal circuit model-based method and device for determining a permissible current of an overhead conductor. The method comprises the steps of: firstly, loading a current to the overhead conductor, after the temperature of the conductor is stabilized, measuring the temperature of the conductor and an environment temperature of an environment where the conductor is in; according to the two temperatures, by adopting a special formula, sequentially calculating an AC resistance and an environment thermal resistance, and the maximum permissible current when the temperature of the conductor reaches 70 DEG C under the current outside environment; and comparing the current current and the maximum permissible current to carry out corresponding compatibility on the overhead conductor, and providing basis for load transfer, scheduling plan and the like, wherein the formula for calculating the environment thermal resistance and the maximum permissible current is based on a steady state thermal circuit model, the maximum permissible current can be obtained through measuring the temperature of the conductor and the environment temperature of the environment where the conductor is in and through simple calculation, and proved by experiments, result errors are in a permissible range.

The invention discloses a fuel cell thermal management system with phase change heat storage and preheating functions. The fuel cell thermal management system comprises a heat pipe heat exchange part,a liquid path preheating loop, a liquid path heating loop, a gas path preheating loop and a gas path heating loop, wherein the heat pipe heat exchange part is embedded into a heat pipe in a polar plate to exchange heat with an external liquid path, a first phase-change heat exchanger is connected with a liquid path, a second phase-change heat exchanger is simultaneously connected with a gas pathand the liquid path, the liquid path preheating loop heats the liquid path through the first phase change heat exchanger, the gas path preheating loop heats the gas path through the second phase change heat exchanger to jointly preheat a fuel cell, waste heat of a fuel cell in the liquid path heating loop accumulates heat for the phase change heat exchanger or heats a lithium battery and a passenger compartment, the gas path heating loop indirectly heats inlet gas through cooling liquid. The fuel cell thermal management system is advantaged in that the waste heat of the fuel cell can be storedin the phase change heat exchanger and used for preheating the fuel cell through a liquid path and a gas path or for heat preservation of the fuel cell, in addition, the waste heat of the fuel cell can heat intake air, a lithium battery or a passenger compartment, and the energy utilization rate is increased.

An IGBT junction temperature thermal calculation method under a fault current relates to a thermal calculation method, and aims to solve the technical problems that an existing method cannot effectively reflect the transient junction temperature of each chip in an IGBT module; the method comprises the following steps: 1, calculating power module loss according to circuit state information and a loss parameter, fitting a manual curve of the IGBT module so as to obtain a conduction voltage drop, an IGBT open loss and a shut down loss, and using an instantaneous power consumption integration in aperiod to represent the loss; 2, obtaining a power device peak junction temperature calculation method under a burst pulse power according to an IGBT peak junction temperature calculation method under a short power pulse, inputting IGBT module thermal property parameters, using the physical parameter of a related layer to simulate a thermal response curve in operation, and building a module system thermal circuit module; 3, determining the IGBT module temperature. The IGBT junction temperature thermal calculation method is reasonable in design, high in precision, and accurate in prediction results.

The invention provides a thermal circuit model-based method for obtaining a coiling hot point temperature of a transformer, which is applied to obtaining of the coiling hot point temperature of the transformer. The method comprises the steps of building an environment temperature-based thermal circuit model according to solar radiation heat and obtaining the coiling hot point temperature of the transformer through the thermal circuit model, wherein the thermal circuit model comprises an average oil temperature model, a top oil temperature model and a coiling hot point temperature model; calculating an average oil temperature according to a differential equation corresponding to the average oil temperature; substituting the calculated average oil temperature into a differential equation corresponding to the top oil temperature model to calculate a top oil temperature; and substituting the calculated top oil temperature into a differential equation corresponding to the coiling hot point temperature model to calculate a coiling hot point temperature. The thermal circuit model-based method for obtaining the coiling hot point temperature of the transformer has the beneficial effects that the coiling hot point temperature is calculated through the thermal circuit model, so that the obtained hot point temperature value is more accurate and the problem in the prior art that the influences of the solar radiation heat and the environment temperature on the coiling hot point temperature are not considered is solved.