Background technology
Along with increasingly sharpening of energy crisis and environmental problem, the thermoelectric cooling mode characteristics outstanding with it based on thermoelectric effect have caused that people more and more pay close attention to.With other refrigeration modes, compare, the thermoelectric cooling mode has advantages of machinery-free moving component, compressor-free, does not use cold-producing medium, compact conformation, noiseless, pollution-free, long service life etc. are unique, is widely used in the instrument and equipment such as military affairs, space flight, the energy, microelectronics, optoelectronic device and industry and commerce product.The greatest problem that thermoelectric cooling mode practical application at present faces is that the refrigerating capacity of thermoelectric refrigerating module is little, is difficult to the electrothermal module performance is assessed, and the performance quality is closely related with the quality of refrigerating plant.
The important parameter of weighing thermoelectric cooling performance quality comprises refrigerating capacity Q, coefficient of performance and figure of merit Z, and classic method is calculated above-mentioned three parameter values according to theoretical formula often.In computation process, the theoretical experiment value that the value of Seebeck coefficient α, all-in resistance R and overall thermal conductance K provides according to electrothermal module production firm, ignored the variation of Seebeck coefficient, all-in resistance and overall thermal conductance that in actual use, the variation of electrothermal module working environment causes, therefore this computing method can not accurately be calculated refrigerating capacity, coefficient of refrigerating performance and the figure of merit of electrothermal module.And fewer about Seebeck coefficient, all-in resistance and the overall thermal conductance data under the different application operating mode of electrothermal module, only limit to the electrothermal module of several models commonly used.Under the practical application operating mode, although the measuring method of electrothermal module Seebeck coefficient, all-in resistance and overall thermal conductance is more, but there is the proving installation complex structure in existing test mode, test process is consuming time longer, the problems such as measuring accuracy is lower, especially in the measurement of the electrothermal module of use, most of method of testings have operability hardly.
Summary of the invention
The utility model is for existing thermoelectric cooling device for measuring properties complex structure, the problem of test process inconvenience, proposed a kind of thermoelectric cooling device for measuring properties, for measuring electrothermal module refrigerating capacity Q under the practical application operating mode, coefficient of performance, the thermal performances such as thermoelectric figure of merit coefficient Z are measured.Device volume is small and exquisite, and cost is low, and test process and method are easy, and result is accurate.
The technical solution of the utility model is: a kind of thermoelectric cooling device for measuring properties comprises tested thermoelectric refrigerating module, confined space, heating wire, water-filled radiator, cold junction thermopair, hot junction thermopair, data collecting instrument, digital power meter, computing machine, vacuum chamber, vacuum pump, thermoelectric refrigerating module, confined space and water-filled radiator are placed in vacuum chamber, place one section heating wire in confined space, thermoelectric refrigerating module is between the confined space as the cold junction unit and the water-filled radiator as the unit, hot junction, the cold junction thermopair is placed on confined space and thermoelectric refrigerating module surface of contact, the hot junction thermopair is placed on water-filled radiator and thermoelectric refrigerating module surface of contact, cold junction thermopair and hot junction thermopair gather cold, the working temperature in hot junction is sent data collecting instrument, digital power meter gathers respectively the operating voltage of thermoelectric refrigerating module, working current, thermoelectromotive force and power of heating wire, the data of computer receiving data Acquisition Instrument and digital power meter collection are also carried out analyzing and processing.
The beneficial effects of the utility model are: the utility model thermoelectric cooling device for measuring properties, and the apparatus structure compact and reasonable, test easyly, and measuring accuracy is high.
Embodiment
Thermoelectric cooling device for measuring properties structural representation as shown in Figure 1, comprise tested thermoelectric refrigerating module 1, confined space 2, heating wire 3, water-filled radiator 4, cold junction thermopair 5, hot junction thermopair 6, data collecting instrument 7, digital power meter 8, computing machine 9, vacuum extractor, vacuum extractor comprises vacuum chamber 10 and vacuum pump 11.Thermoelectric refrigerating module 1, confined space 2 and water-filled radiator 4 are placed in vacuum chamber 10, and the cold junction unit is a confined space 2, place one section heating wire 3 in space, the simulation loading thermal load, and can be by regulating the load of electric-heating-wire-heating power analog variable; The unit, hot junction is water-filled radiator 4, is used for controlling thermoelectric refrigerating module 1 hot-side temperature; Thermoelectric refrigerating module 1 is between confined space 2 and water-filled radiator 4, and cold junction thermopair 5 is placed on confined space 2 and thermoelectric refrigerating module 1 surface of contact, and hot junction thermopair 6 is placed on water-filled radiator 4 and thermoelectric refrigerating module 1 surface of contact.
The data acquisition process unit comprises cold junction thermopair 5 and hot junction thermopair 6, data collecting instrument 7, digital power meter 8 and computing machine 9.Thermopair gathers the working temperature of cool and heat ends and send data collecting instrument 7; Digital power meter 8 gathers respectively operating voltage and the working current of thermoelectric refrigerating module 1, thermoelectromotive force, and the power of heating wire 3; Computing machine 9 receives the data of data collecting instrument 7 and digital power meter 8 collections and carries out analyzing and processing.
Vacuum extractor contains vacuum chamber 10 and vacuum pump 11, is used for control system vacuum tightness to 10
-3below Pa, therefore can ignore the impact of cross-ventilation heat exchange.
During test experiments carries out, the measuring principle of the several work electrical quantitys of thermoelectric refrigerating module 1 as shown in Figure 2.Passage 1 surveying work voltage, passage 2 surveying work electric currents, passage 3 is measured thermoelectromotive force.After test macro reaches and stablizes, record now operating voltage and current value, stir switch, cut off the power supply of thermoelectric refrigerating module 1, connect the measurement passage of thermoelectromotive force, in order to eliminate switching noise, the sampled signal obtained, the measurement of thermoelectromotive force needs an of short duration time delay (t=0.5s), so just can obtain the thermoelectromotive force value of electrothermal module.
Concrete steps and method can operate in the requsst listed below:
1) open vacuum pump 11, control system vacuum tightness to 10
-3below Pa.
2) the performance parameter table provided according to producer, the operating voltage of regulating tested electrothermal module 1, find the maximum temperature difference operating mode, utilizes cold junction thermopair 5 to measure the cold junction work temperature
c ', hot junction thermopair 6 is measured the hot junction work temperature
h ', with data collecting instrument 7 collecting temperature signal T
c 'and T
h ', utilize digital power meter 8 record operating voltage V now
max, working current I
maxwith thermoelectromotive force E
max, by 9 storages of all data input computing machines, calculating and demonstration.
The temperature T of the electrothermal module hot junction face that 3) basis measures
h 'with voltage V
max, utilize computing machine 9 to calculate the Seebeck coefficient α of electrothermal module;
4) according to the electrothermal module operating voltage V measured
max, electric current I
maxand thermoelectromotive force value E
max, utilize computing machine 9 to calculate the all-in resistance R of described electrothermal module;
5) according to the electrothermal module operating voltage V measured
max, electric current I
max, thermoelectromotive force value E
maxand hot junction surface temperature T
h ', utilize computing machine 9 to calculate the overall thermal conductance K of described electrothermal module;
6) adjust the supply voltage of electrothermal module 1, regulate heating wire 3 heating powers simultaneously, load a thermal load to the module cold junction, after system to be tested reaches and stablizes, utilize cold junction thermopair 5 to measure the cold junction work temperature
c, hot junction thermopair 6 is measured the hot junction work temperature
h, with data collecting instrument 7 collecting temperature signal T
cand T
h, utilizing digital power meter 8 record operating voltage V now, working current I and thermoelectromotive force E, preserve all data input computing machines 9, process.
7) according to calculating gained α, R, K and measuring gained I, T
h, T
c, can utilize computing machine 9 to calculate refrigerating capacity
q, the electric power of consumption
p, coefficient of performance, thermoelectric figure of merit coefficient
z, complete performance measurement
.
8) measurement of electrothermal module performance under different hot-side temperatures: the cooling water temperature changed by water-filled radiator 4 can change the thermoelectric refrigerating module hot-side temperature, repeats above-mentioned steps, thereby completes the performance measurement of thermoelectric refrigerating module under different hot-side temperatures.