Description

Technical field:

The technical field is the conversion of heat flux into energy and electricity.

Technical problem:

Nowadays, given fossil fuels scarcity and rising trend of level of energy consumption in the current world, present energy resources no longer will be reliable. Since thermoelectric generators are characterized with low electrical power generation efficiency, these generators in the industry have been limited to specific applications. However this does not mean that using such generators in different industries is impossible, as efficiency and application of the system can be improved using the symbiotic method (electrical and thermal power) and the best way to storing generated electrical power is by storing electrical power in electrical power sources such as batteries and thermal power can be stored and used depending on its usage.

Prior Art:

Literature is full with many research and experiments carried out to electricity and thermal power generation from waste heat sources in the world. In most cases, thermoelectric generators were tested alone without thermal power. In these experiments, sometimes installation of thermoelectric generators changed the structure of combustion by-products. In other researches, some common mechanisms to generate thermal power along with electrical power generation were utilized that increased the use of these generators. To generate electrical power, thermoelectric generators must be connected to a hot and a cold surface, so that the temperature gradient between two levels of the generator will allow the heat to flow from the warmer surface of the generator to a cooler surface, which in that case electric power is generated (Seebeck effect).

In these researches, water was used to cool the generator thermoelectric surface, to as well as creating a cool surface for this generator and eventually generating electrical power, the heat flux passing thermoelectric generator be absorbed by the water and cause an increase in the temperature of water. But due to complicated structure and low efficiency, these methods are not industrially valuable.

Summary of the invention: This invention, which is a new symbiotic and practical method, is able to absorbing and utilizing heat and converts it into electrical energy by thermoelectricity, in such a way that electrical energy can be stored in energy storage sources, including batteries. This system has the capability of absorbing waste heat from the heat sources and converting the energy lost to the electrical and thermal power simultaneously. The electrical power generated should be stored in power supplies such as batteries, so that the power generated can be used for other matters.

Since changes in the temperature gradient lead to changes in the generated electrical power, a buck-boost converter with the ability to track the maximum power point (MPPT) has been applied so that temperature changes do not disrupt the charging process of the battery and a charger circuit, which is capable of disconnecting the generator's path to the battery when the battery is charged, or reconnecting the charging path in the event of a drop in battery power is available.

In this invention, a very efficient economizer is also installed at the exhaust of hot and waste gases so that after using the waste heat to generate electrical power, the rest of these excess heats passing through the system will generate high thermal power and warm water outlet applied to the system relative to the entry water.

These features (electric and thermal power generation) will save you a lot of energy, which is also important and as there is no alternative to removing moving parts in this system, so there is no friction and service life of device will be prolonged. No pollution is created during power generation, all of which adds to the great benefits of this invention. According to the principle that after combustion, hot gases are transferred to the system's exhaust, a mechanism is needed in order to utilize and recycle waste heats to productive powers, in order to maximize energy consumption and the lowest level of dispersion of pollution to the environment. This invention is installed on exhaust of combustion products, and hot waste gases are entering the inlet of this invention, rises temperature in heat sink, and a hot surface required for the hot wall of the thermoelectric generator is created. At this time, water enters the cooling block of and causes cooling and absorbing heat from the thermoelectric wall of the generator, which should be connected to the cooler generator's surface. The heat from the generator to the cooling block will warm up the water.

However, as it was aforementioned, this amount of absorbed heat is low and cannot be considered as cost-effective Economizer. Therefore, finned tube were used at exhaust of this invention so that after using some amount of waste heat for electric power generation the rest of the heat passing through the empty space between the heatsink blades instead of reaching the atmosphere hits finned tubes (economizers) and absorbed through fins and transferred to the water passing through the economizer from the cooling block to increase the temperature of the water and thereby increases heat power. As a whole, this invention thanks to its simple structure and low design cost along with long servicing lifetime of the device, and the ability to produce both electrical and thermal power as unit at excellent level, and easy installation on hot gas paths and without pollution, serves as a promising and practical step to optimize energy consumption.

Brief description of drawings:

This system has several important parts as following:

1- Heatsink (in aluminum) and cooling block

2. Thermoelectric generator

3- buck-boost converter (MPPT)

4. Charge circuit to disconnect or reconnect the charging path

Detailed description of drawings:

In Figure 1 , waste heat is introduced into system through gas inlet (1), which causes the aluminum heatsinks to heat up (2) and thus generate electrical power. The electric power produced by Thermoelectric generator goes to the buck-boost (3) converter and can be transmitted with tracking the maximum power point (mppt), which is used to create safe conditions for battery charging, especially when the system is facing temperature change. Thermoelectric generators generate power under seebeck effect which is TEHP1-12656-0.3 type and are installed on each side of the device for maximum absorption. The change in the temperature gradient of the system causes a change in the electrical power produced by the system. Therefore, we need a buck-boost converter to increase or decrease the voltage to increase it if the voltage drops, or if the voltage is too high, it reduces the amount needed Set up The buck-boost converter used in this system is LTC 3780, which will be described in the following. The voltage regulated to a charger is transmitted to control the charge level of the battery. This charger checks the battery voltage and, if required, will enable the battery charging path and, conversely, if the battery is fully charged, it will deactivate the battery charge.

Heat sink

The hot surface between which and cooling block water thermoelectric generator is located (4). Fins help to absorb more heat and heats up the generator's surface. The important point in this case is that the amount of energy injected by screws on the wall of thermoelectric generators is enough to press enough to increase contact surfaces and improve the quality of power generation. The heat transfer paste has also been used to fill the empty surfaces on the generator wall and metal surfaces (heatsink and cooling block). The following table, which is part of the generator information, shows the amount of energy input from the closure of the screws to increase the contact surface in such a way as to achieve the best efficiency in Table 1.

Cooling block:

This block (5) is made of an aluminum sheet. The inlet of this cooling block is the cooling water of the city and outlet is connected to inlet of the coil Economizer tube to warm the outlet water from the cooling block, the output of the economizer is actually the final output of the invented system, and these parts are jointly make up a connected and unit system.

The important point in this case is canal shape on aluminum sheet, so that to cooling it was attempted to elevate level of entering water and, on the other hand, does not reduce the excess water flow (water pressure). This makes it possible to cool the thermoelectric generator's surface to the temperature required for greater efficiency.

Buck-boost converter:

DC Voltage converter is a buck-boost DC-DC automatic converter that automatically maintains the output voltage in constant manner.

Charge circuit for 6 and 12 volt batteries (sealed lead acid)

This is a charging circuit for 6 and 12 volt batteries. In this circuit, an AVR series microcontroller is used to charge and control the battery voltage in order to disconnect the charger in order to prevent damage to battery and prolong battery life.

Fig. 6 illustrates an Economizer part whose main function is to converting waste heat energy after generating electrical power by thermoelectric generator to thermal power. The heat is absorbed by the fins and transferred to the water to allow the water extracted from the system to appear at a higher temperature than the water entering it.

Figure 7 is control valve of the exhaust gas in invented system, which can be tuned in manual and automatic manner.

Figure 8 is Buck-boost converter used in designing invented device, which its function is adjusting the battery voltage due to changes in the generation of electrical power by the thermoelectric generator.

Fig. 9 is sealed lead acid battery charger circuit that was designed and manufactured in conjunction with the inventive device, which is one of the main components of the invention, such as a thermoelectric generator and an economizer.