CN104154482A - Steam compressing type refrigeration/thermoelectric conversion combined type LED lighting device - Google Patents

Abstract

The invention relates to a vapor compression refrigeration/thermoelectric conversion combined LED lighting device, comprising an LED planar light source, a vapor compression refrigeration system, and a heat recovery device; the LED planar light source includes an LED chip and a circuit layer packaged on the lower surface of an inner substrate, Sealing layer and insulating layer; the vapor compression refrigeration system includes a compressor, a condenser, a throttle valve, and an evaporator, and the evaporator is closely attached to the upper surface of the inner substrate to cool the LED chip; the heat recovery device includes a thermoelectric converter, a cooling fin The hot end of the thermoelectric converter is in close contact with the outer surface of the inner substrate and the tube-and-belt condenser, and correspondingly, the cold end is respectively in close contact with the outer substrate with cooling fins and the fins in the condenser. After the cold and hot ends of each thermoelectric converter are connected in parallel, the output wires are connected to the electric energy storage unit, and the electric energy storage unit distributes the electric energy to the LED light source. The invention satisfies the high heat flux heat dissipation requirement of the high-power LED chip, and also realizes the recovery and utilization of waste heat.

Description

Vapor compression refrigeration/thermoelectric conversion combined LED lighting device

technical field

The invention relates to a vapor compression refrigeration/thermoelectric conversion combined LED lighting device.

Background technique

LED light source is a kind of cold light source. At present, the luminous efficiency of the chip can only reach 10%-20%, and 80%-90% of its energy is converted into heat energy. With the high integration of LED, the heat accumulation inside the chip and the rise of the junction temperature of the chip lead to a series of problems such as the drift of the luminous wavelength, the decrease of the light output efficiency, the accelerated aging of the phosphor powder, and the shortened service life. The development of high-efficiency and energy-saving LED lighting devices is the field research focus.

Under natural convection, in order to ensure that the LED can work safely, its power should not exceed 1W; for high-density and high-power LEDs, active cooling solutions such as forced air convection, liquid cooling, thermoelectric cooling, and loop heat pipes should be considered. B.J.Huang from Taiwan National University designed a vapor compression refrigeration system for high-power LED heat dissipation in 2009, aiming at the bottleneck of high-power LED equipment in high-temperature environments. Hu Hongli of Xi'an Jiaotong University proposed an LED lighting device that can realize heat recovery in 2008. The device uses heat pipe technology to dissipate heat from LEDs, and uses thermoelectric conversion devices to recover LED waste heat.

Contents of the invention

The invention proposes a high-efficiency and energy-saving LED lighting device, which organically combines a vapor compression refrigeration system and a thermoelectric conversion device to meet the heat dissipation requirements of high-power LED equipment, and at the same time recovers the heat discharged from the LED chip and the refrigeration system, making it for electric energy reuse.

The invention proposes a vapor compression refrigeration/thermoelectric conversion combined LED lighting device, which includes an LED planar light source, a vapor compression refrigeration system, and a heat recovery device; the LED planar light source includes an LED chip and its circuit layer, sealing layer and insulating layer , encapsulated on the lower surface of the box-shaped inner substrate by welding (or silicone grease); the vapor compression refrigeration system includes an evaporator, a condenser, a compressor, and a throttle valve, and the evaporator is closely attached to the upper surface of the inner substrate to absorb the heat, thereby cooling the LED chip; the heat recovery device includes a thermoelectric converter, heat dissipation fins and an electric energy storage unit. The outer substrate with fins is closely attached to the fins of the tube-and-belt condenser. The cold and hot ends of each thermoelectric converter are connected in parallel and then connected to the electric energy storage unit by the output wire. The electric energy storage unit distributes the electric energy to the LED light source.

The advantages of the present invention are:

First, the vapor compression refrigeration system has a higher COP. Compared with traditional air forced convection, liquid cooling, thermoelectric refrigeration, loop heat pipe and other active cooling solutions, it has a more efficient heat dissipation effect and breaks through the heat dissipation bottleneck of high-power LED light sources. Better Solve a series of problems such as the drift of the luminous wavelength of the LED light source due to high temperature, the decrease of the light output efficiency, the accelerated aging of the phosphor powder, and the shortened service life. Second, the invention not only recovers the waste heat generated by the LED light source by using the semiconductor thermoelectric converter, but also recovers the heat released by the condenser, improves the efficiency of the refrigeration system, and realizes the technical effect of energy saving and environmental protection.

Description of drawings

Fig. 1 is a front view of the overall structure of a vapor compression refrigeration/thermoelectric conversion combined LED lighting device according to the present invention.

FIG. 2 is a top view of FIG. 1 .

From Figure 1 to Figure 2: 1. LED planar light source; 2. Electric energy storage unit; 3. Output wire; 4. Box-shaped inner substrate; 5. 11. Chip thermoelectric converter; 6. Outer substrate; Radiating fins; 8. Evaporator; 9. Compressor; 10. Tube-belt condenser; 13. Throttle valve.

Detailed ways

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 1 and Fig. 2, the vapor compression refrigeration/thermoelectric conversion combined LED lighting device of the present invention includes three parts: LED planar light source, vapor compression refrigeration system, and heat recovery device. The LED planar light source 1 may include an LED chip and its circuit layer, a sealing layer and an insulating layer, and is packaged on the lower surface of the inner substrate 4 . The vapor compression refrigeration system includes an evaporator 8 , a compressor 9 , a tube-and-belt condenser 10 , and a throttle valve 13 . The evaporator 8 is in close contact with the upper surface of the inner base plate 4 . The heat recovery device may include sheet-type thermoelectric converters 5, 11, cooling fins 7, 12, and an electric energy storage unit 2. The hot end of the thermoelectric converter 5 is in close contact with the outer surface of the inner substrate 4, and the cold end is in close contact with the outer surface of the inner substrate 4. The outer substrate 6 of the heat dissipation fin 7, the hot end of the thermoelectric converter 11 is close to the tube-band condenser 10, and the cold end is close to the heat dissipation fin 12 of the tube-band condenser 10. After the hot end is connected in parallel, the output wire 3 is connected to the electric energy storage unit 2 , and the electric energy storage unit 2 distributes electric energy to the LED light source 1 .

The vapor compression refrigeration system utilizes the low-boiling-point refrigerant to vaporize in the evaporator 8 to realize the constant-pressure heat absorption process, that is, to absorb the heat of the LED chips exported through the inner substrate 4 to achieve the effect of cooling. Then the dry saturated vapor of the refrigerant coming out of the evaporator 8 is sucked into the compressor 9, and becomes a superheated vapor after adiabatic compression, enters the condenser 10, condenses into a saturated liquid at a constant pressure and temperature, releases heat to the outside, and then passes through the throttle valve 13. After adiabatic throttling and pressure reduction, it becomes wet steam with low dryness, and then the wet steam is introduced into the evaporator to realize a cycle.

Chip type thermoelectric converters, 5 and 11 are made according to the Seebeck effect, that is, the joint ends of two semiconductors are placed in a high-temperature environment, and the electromotive force E can be obtained at the other end in a low-temperature environment. And the magnitude of the electromotive force E is proportional to the temperature difference between the nodes.

According to a specific embodiment of the present invention, comprise following three steps:

In the first step, after the LED light source 1 is powered on, 80%-90% of the energy is converted into heat energy, and the heat is dissipated on the surface by the box-shaped inner substrate 4 made of high thermal conductivity material.

In the second step, after the vapor compression refrigeration system consisting of evaporator 8, compressor 9, tube-and-belt condenser 10, and throttle valve 13 works, the evaporator 8 that is closely attached to the upper surface of the inner substrate 4 performs the heat absorption process , to absorb the LED waste heat conducted by the inner substrate 4, and the thermal insulation layer made of rubber and plastic sponge material above the evaporator 8 is packaged to promote heat exchange efficiency.

In the third step, the chip thermoelectric converter 5 is placed between the inner substrate 4 and the outer substrate 6, and the heat conducted by the inner substrate heats the chip thermoelectric converter 5 to form a hot end, while the other side of the chip thermoelectric converter 5 It is closely attached to the outer substrate 6 equipped with cooling fins 7 to form a cold end, and a large temperature difference is formed between the hot and cold ends of the thermoelectric converter 5 to generate current. The other part of the plate-type thermoelectric converter 11 is installed above each flat tube of the tube-belt condenser 10 (except the uppermost flat tube). Since the refrigerant condenses and releases heat in the tube-band condenser 10, the plate-type thermoelectric The heating surface of the device 11 forms a hot end, and the other surface of the chip thermoelectric converter 11 is in contact with the cooling fins 12 between the flat tubes of the tube-strip condenser 10 to form a cold end. A large temperature difference is formed between the cold end and the hot end of the thermoelectric converter 11 to generate electric current. The current generated by the thermoelectric converters 5 and 11 is output through the output wire 3 and stored in the electric energy storage unit 2 to supply power for the lighting of the LED light source.

The chip type thermoelectric converter of the device of the present invention is composed of multiple semiconductor thermoelectric power generation components connected in parallel, and the number and type of the components are determined by the size of the inner substrate and the tube-band condenser. The size of the inner base plate and the tube-band condenser is determined by the power of the LED lamp. Considering the comprehensive factors of cost and efficiency, the outer base plate and the cooling fins of the tube-and-belt condenser are made of aluminum alloy, and the inner and outer base plates are made of copper with better thermal conductivity. In order to prevent the evaporator from leaking heat to the environment, thermal insulation materials are applied externally.

The above description is only an embodiment of the present invention, and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of the claims of the present invention.

Claims (4)

1. steam compression type refrigeration/thermoelectricity conversion group mould assembly LED lighting device, comprises LED planar light source, it is characterized in that, also comprises vapour compression refrigeration system and heat reclaim unit; Described LED lighting device comprises LED chip and circuit layer, sealant and insulating barrier, is encapsulated in the lower surface of substrate in box-like; Described vapour compression refrigeration system comprises evaporimeter, condenser, compressor, choke valve; Described heat reclaim unit comprises chip thermoelectric converter, radiating fin and power storaging unit.

2. steam compression type refrigeration/thermoelectricity conversion group mould assembly LED lighting device according to claim 1, it is characterized in that, described evaporimeter and interior upper surface of base plate are close to, and by evaporimeter inner refrigerant, vaporize, the heat of substrate conduction in absorbing, evaporimeter outside is encapsulated by heat-insulation layer.

3. steam compression type refrigeration/thermoelectricity conversion group mould assembly LED lighting device according to claim 1, it is characterized in that, described chip thermoelectric converter is hot junction with the one side that interior substrate outside and serpentine condenser are close to respectively, cold junction is corresponding thereto close to respectively the fin of outer substrate and the fin of serpentine condenser, the cool and heat ends of each thermoelectric converter connects a power storaging unit that is arranged on evaporimeter one side by output lead after by parallel connection, this power storaging unit by power distribution to LED planar light source auxiliary light emission.

4. steam compression type refrigeration/thermoelectricity conversion group mould assembly LED lighting device according to claim 3, it is characterized in that, described serpentine condenser air side is installed aluminium alloy window formula fin, chip thermoelectric converter is arranged on the top (last layer flat tube except) of every flat tube, and the height of chip thermoelectric converter top fin is the thickness that flat tube gap deducts thermoelectric converter.