SK1072006A3 - Cross thermo-magnetic generator - Google Patents

Abstract

The invention is intended for the production of electricity from low potential heat from any renewable or waste heat source. Arrangement of the magnetic source (3) flow of magnetic circuits, thermal breaker (2) and the coil (7) allows to change the polarity of the magnetic flux in a coil core (7) of relatively high frequency and preferred specific power of the generator. thermomagnetic elements of amorphous metal with steep temperature dependence allow the use of a 5 ° K temperature gradient. cascade the arrangement of thermomagnetic elements greatly increases the energy conversion efficiency of the temperature gradient above 5 ° K.

Description

The invention relates to low-potential heat power generators, refrigeration equipment, air-conditioning equipment, cryogenic equipment.

BACKGROUND OF THE INVENTION

Thermomagnetic power generators induce electrical energy by periodically heating and cooling the magnetic circuit or a portion of it around the curie point and inducing electrical voltage in the coil by changing the magnetic flux. The currently known designs achieve a low rate of change in the pulsation mode, i. without reversing the magnetic flux to the core of the coil. The relatively low output voltage does not allow industrially widespread power generation and impairs the efficiency of converting low potential heat into electricity.

SUMMARY OF THE INVENTION

The principle of the solution is a cross-arrangement of a magnetic circuit in which the source of magnetic flux can be a permanent magnet, e.g. a neodymium or superconducting magnet, the opposite poles of which are coupled to magnetically soft frequency-resistant flow branches into four thermal interrupters consisting of elements of a thermomagnetic material whose curie temperature is between the heat source and the cold source and whose pairs are interconnected by forks the centers are connected by the core of the coil. The heat and cold source are arranged on the cross so that in the period when the two thermal breakers are heated by the diagonal as a result of the transfer of the heat transfer medium, the remaining two on the cross diagonal are cooled. Thus, the magnetic flux flows in one direction of the core of the coil. In the opposite period, the magnetic flux is reversed.

The transfer of hot and cold medium through elements of thermomagnetic material (eg 0.02 mm amorphous metal strips) can be exchangers from exchangers, but also the effect of compressed air from pressure vessels by periodically opening four valves for each thermal breaker. The discharge valve from the pressure vessel of one temperature side and the inlet valve of the low pressure vessel of the opposite temperature side are always open at the same time. There is a heat exchanger and a pump between the pressure vessel and the low pressure vessel. This arrangement makes it possible to use an exchanger of any size in a hot or cold part, regardless of the size and ground plan of the device.

Quality thermomagnetic materials lose 90% magnetization at 5 ° C change. At a temperature gradient greater than 5 ° C, the thermal interrupter in the flow direction is split and assembled from thermomagnetic materials of different curie temperatures into cascades so that the heat transfer medium only heats each cascade by a single thermal gradient. The waste heat of the higher cascade is a source of heat for the lower.

The source of heat and cold may also be thermal oscillating sources in which the cooling factor (COP) is higher than the inverse of the efficiency of the thermomagnetic cycle. This is the case in a magnetocalor circuit perpendicular to the magnetic flux of thermal breakers. Magnetocaloric tapes routed through thermomagnetic elements - tapes with thermal contact with them are characterized by gigantic magnetocaloric phenomenon and their curie temperature is 3 ° C higher than the curie temperature of thermomagnetic elements. The pulsating magnetic flux from the coil heats and cools them without interrupting the magnetic flux in the magnetocaloric circuit. The thermomagnetic circuit in perpendicular direction is periodically interrupted by temperature changes. A low change in magnetization in the magnetocaloric circuit causes a high cooling and heating factor (COP) in the generation and removal of heat and cold into the thermomagnetic elements. The result is the cooling effect of the entire system and the need to supply only heat to the heat transfer medium supplied by the pump with temperature control of the thermomagnetic elements.

Analogously, the source of heat and cold may be electrodes in an electrocaloric circuit in which the strips of electrocaloric material heat the thermomagnetic elements resulting in induction of the output voltage in the coil. Higher specific heat when heating the tapes than when cooling the tapes produces a cooling effect with the need for heat supply by the pump.

Description of pictures

In FIG. 1 is a plan view of the device from below without heat sinks.

Fig. 2 is a side view and partial sectional views.

Fig. 3 is a diagram of the transfer of the heat transfer medium through one thermal breaker by means of four actuated valves and pressure vessels

Fig. 4 is a diagram of heating and cooling the thermomagnetic elements with cross strips of magnetocaloric or electrocaloric material.

DETAILED DESCRIPTION OF THE INVENTION

A cross-type thermomagnetic generator designed to convert low-potential heat of geothermal or solar origin into electrical energy in one cascade receives 40 ° C hot water and 20 ° C cold water into the heat source. Thermomagnetic elements in channels of thermal breakers in the form of 0.02 mm strips of amorphous metal are made of alloy MnFePo, 45Aso, 55, whose curie temperature is about 305 K. In a magnetic field of 1 T material loses 90% of magnetization at 305 K, magnetization takes place at 300 K. After leakage losses in the heat exchangers 11 of FIG. 3, 307 K is in the hot pressure vessels 12 and 279 K in the cold pressure vessels 12 '. Starting the control of the outlet controlled valves 14 and the inlet controlled valves 13 in the anti-phase mode of the cross pairs will achieve periodic heating and cooling of thermodynamic elements - thermal breaker tapes 2 and periodic polarity reversal of the magnetic flux in the coil core 7. ² and a frequency of 20 Hz thermal oscillations, the hydraulic resistance of the tapes of thermodynamic elements is 10 ⁵ Pa, with the need for a return water flow in four thermal breakers of 0.1 x 0.1 x 0.02 m and 4.10 ³ m ³ / s, so 400 W for pumping water into 1 t of pressure vessels, approx. 500 W.

The generator power is U ² / R, where U = BSf = 2T.10m ² .20 Hz = 400 V at 1000 turns of 4 Ω coil resistance and 40 Ω of total load, the total electrical power in the coil is 160/40 = 4 kW. In the partial regenerative effect of thermomagnetic tapes, the heat consumption is Q = 2kg.4200.10K + Q - 84 kW + 16 kW = 100 kW, with Q 'being the magnetocaloric losses.

The energy conversion efficiency of an installation shall be:

5kW _{= = 5} which is 3.5%

100ÄJF

Given the cheaply obtained heat (black hoses, common geothermal water), this is satisfactory efficiency.

Other embodiments significantly increase efficiency with respect to cascades at a higher temperature gradient and a lower proportion of heat exchanger losses, due to the progressive thermodynamic effects of magnetocaloric and electrocaloric oscillators.

Claims (6)

PATENT CLAIMS A cross-type thermomagnetic generator inducing electrical voltage by interrupting the magnetic flux by heating and cooling a ferromagnetic substance around its curie point is characterized in that the magnetic circuit forms a source of magnetic flux (3), the opposite poles of which are connected to flow branches (4) into four thermal breakers. (2), the pairs of which are interconnected by forks (1), the centers of which are interconnected by the core of the coil (7), the thermal breakers (2) comprising elements of a magnetically soft thermomagnetic material with a curie point whose temperature value is between heating and cooling heights supplied from heat sources (5A) and (5B) and cold sources (6A) and (6B) to thermal breakers (2). 2. The cross-type thermomagnetic generator according to claim 1, characterized in that the heat sources (5A) and (5B) and the cold sources (6A) and (6B) are positioned mutually on the cross such that when the shifters (9A) are the heat transfer fluid is in the position of transfer of the heat fluid (5A) to the cold sources (6A), and the shifters (9B) are in the position of fluid transfer from the cold sources (6B) to the heat sources (5B). connected to oscillators (8) having a reciprocating amplitude drive of pairs uniform across the diagonal of the device. 3. The cross-type thermomagnetic generator according to claim 1, characterized in that the heat sources (5A) and (5B) and the cold sources (6A) and (6B) are pressure vessels (12) filled with heat transfer fluid by pumps (10) through exchangers (11). from the low pressure vessels (19) or the surrounding hot and cold water connected to the discharge control valve (13) to the thermal breaker channel (2) and the inlet control valve (14) to the low pressure vessel (19), the outlet from the heat source (5A) to The cold source (6A) is reciprocal to the outlet from the cold source (6B) to the heat source (5B). 4. The cross-type thermomagnetic generator according to claim 1, characterized in that the elements of the magnetically soft thermomagnetic thermal breaker (2) are separated and cascaded with different curie temperatures from the highest at the heat sources (5A) and (5B) up to the heat sources. lowest for cold sources (6A) and (6B). 5. The cross-type thermomagnetic generator according to claim 1, characterized in that the heat sources (5A) and (5B) and the cold sources (6A) and (6B) are magnetocaloric oscillatory circuits composed of a coil (16), arms (17). of insulated layers and cross strips (15) are of material marked by magnetocaloric phenomenon and their curie point is 2 ° to 4 ° C lower than the curie point of elements of thermal breakers (2), heat transfer fluid is led by pump (18) through shoulder gaps (17) and gaps in the thermal breaker (2) with the transverse strips (15). 6. The cross-type thermomagnetic generator according to claim 1, characterized in that the heat sources (5A) and (5B) and the cold sources (6A) and (6B) are electrocaloric oscillating circuits consisting of a resonant voltage oscillator (16), electret tapes. (15), the outer conductive layers of which are connected to the opposite polarity of the voltage and their surfaces are in thermal contact with the elementary thermal interrupter (2).