Source: Performance calculation of semiconductor cooler
Before applying the cooler, to further understand its performance, in fact, the cold end of the cooler from the surrounding absorption of heat qл, there are two: one is the focal deposited QJ, the other is conductive heat qk. The current from the inside of the element through the resulting coke deposited, half of the coke deposited to the cold end, the other half to the hot end, conduction heat from the hot end to cold junction.
Cold Production capacity
Qc = Qπ-qj-qk = (2p-2n). Tc.i-1/2j²r-k (TH-TC)
Type, R represents the total resistance of a pair of electric pairs, and K is the total heat conduction.
Hot end the heat that is scattered away
Qh = Qπ+qj-qk = (2p-2n). Th.i+1/2i²r-k (TH-TC)
As can be seen from the above two formula, the electrical power of the input is exactly the thermal end of the heat and the cold end of the absorption of heat difference, this is a "heat pump" one:
Qh-qc=i²r=p
From the above to obtain an electric couple in the hot end release of the Heat QH equals the input electrical power and cold end of the sum of cold production, on the contrary, the cold end of the production of cold output is equal to the amount of hot end emitted by the heat and input power difference.
Qh=p+qc
Qc=qh-p
Calculation method of maximum cooling power
A.1 at the hot end temperature th is 27℃±1℃, the temperature difference is t=0, I=imax.
Maximum cooling power qcmax (W) calculated by formula (1): Qcmax=0.07ni
(1) in the type: N---device logarithm, I---The device's maximum temperature difference current (A).
A.2 if the hot surface temperature is 3~40℃, the maximum cooling power Qcmax (W) should be corrected by formula (2).
Qcmax∣th= qcmaxx[1+0.0042 (th--27)]
(2) in the type: Qcmax---Hot surface temperature th=27℃±1℃ maximum cooling power (W),
Qcmax∣th-The maximum cooling power (W) at the measured temperature of the hot surface temperature Th--3~40℃.
Performance calculation of semiconductor refrigeration device