Thermoelectric Cogeneration System and Battery Dual-Source Parallel Self-Balancing Power Supply Method and Device

Abstract

The present disclosure provides a method and device for self-balanced power supply with a combined heat and power system and a battery in dual-source parallel connection, belonging to the technical field of thermoelectric power generation. First, the battery supplies power to the heating device alone. The high-temperature gas discharged from the heating device is introduced into the combined heat and power system, and the thermoelectric device directly converts thermal energy into electrical energy for output. When the output voltage of the thermoelectric device reaches the voltage required by the heating device, the thermoelectric device and the battery are connected in parallel to supply power to the heating device. As the heat of the high-temperature gas discharged from the heating device increases, the output current of the thermoelectric device increases and gradually replaces the parallel-connected battery. When the output current of the battery gradually decreases to 0, the thermoelectric device charges the battery while supplying power to the heating device. Using the present invention can make full use of the thermal energy of the heating device, while making up for the disadvantage of the poor performance of the battery at low temperatures, and also charging the battery while meeting the power consumption requirements of the heating device, making up for the previous consumption of the battery and reserving energy for subsequent use.

Description

Technical Field

[0001] The present invention relates to the technical field of thermoelectric power generation, and particularly to a dual-source parallel self-balancing power supply method and device for the output electric energy of a combined heat and power supply system and a battery, which is applicable to the working process of a combined heat and power supply system. Background Art

[0002] Energy shortage is an important challenge currently faced globally, and energy conservation and efficiency improvement have become the core themes of industrial development. Thermoelectric power generation technology is a technology that directly converts heat energy into electrical energy based on semiconductor thermoelectric materials. However, due to the unreasonable utilization of the output electrical energy, the application degree of thermoelectric power generation technology is not extensive.

[0003] For vehicles, when the vehicle cannot be started normally in a low-temperature environment, a heating device needs to be added in the vehicle to heat and preheat the vehicle. However, the heating device requires additional electrical energy for power supply, and the battery performance deteriorates in the low-temperature state and cannot provide persistent power supply.

[0004] In view of the problem of low electrical energy utilization rate of thermoelectric power generation technology, the present invention designs a self-balancing power supply scheme in combination with the heating requirement of vehicles. Summary of the Invention

[0005] In view of this, the present invention provides a dual-source parallel self-balancing power supply method and device for a combined heat and power supply system and a battery. This scheme connects the combined heat and power supply system and the battery in parallel, and supplies power to the heating device in the vehicle at different times. First, the battery supplies power to start the heating device. The high-temperature gas discharged by the heating device is introduced into the combined heat and power supply system, and the thermoelectric device in the combined heat and power supply system directly converts the heat energy into electrical energy, which is connected in parallel with the battery to supply power to the heating system. Then the battery gradually withdraws from power supply and is charged and compensated by the combined heat and power supply system, thereby realizing a self-balancing power supply based on a thermoelectric-battery dual-source parallel connection, making full use of the heat energy of the heating device, while making up for the disadvantage of poor battery performance in the low-temperature state, and also charging the battery while meeting the power consumption requirements of the heating device, making up for the previous consumption of the battery and reserving energy for the next use.

[0006] In order to solve the above technical problems, the present invention is implemented as follows.

[0007] A dual-source parallel self-balancing power supply method for a combined heat and power supply system and a battery, which is used to supply power to a heating device in a vehicle; the method includes a first stage and a second stage;

[0008] The first stage: The battery supplies power to the heating device alone. The high-temperature gas discharged by the heating device is introduced into the combined heat and power supply system, and the thermoelectric device in the combined heat and power supply system converts the heat energy into electrical energy for output; when the output voltage of the combined heat and power supply system reaches the voltage required by the heating device, it enters the second stage;

[0009] Stage 2: The thermoelectric device and the battery are connected in parallel to supply power to the heating device; as the heat of the high-temperature gas discharged by the heating device increases, the output current of the thermoelectric device increases and gradually replaces the parallel-connected battery; when the output current of the battery gradually decreases to 0, the thermoelectric device starts to charge the battery while supplying power to the heating device; according to the changes in the output voltage and current of the battery and the thermoelectric device, calculate the working time required for the thermoelectric device to compensate for the power consumption of the battery in Stage 1 while supplying power to the heating device T ; after the working time of the thermoelectric device reaches T , stop the thermoelectric device and the battery from supplying power to the heating device, and the heating device stops operating.

[0010] Preferably, when the thermoelectric device of the cogeneration system converts thermal energy into electrical energy output, maximum power point tracking (MPPT) control is performed to make the electrical energy output from the thermoelectric device to the heating device operate at the maximum power point.

[0011] Preferably, the voltage output terminal of the thermoelectric device is connected to a buck circuit, and the buck circuit serves as the load of the thermoelectric device. The MPPT control process adjusts the output voltage of the thermoelectric device of the cogeneration system by controlling the duty cycle of the buck circuit, so that the electrical energy output from the thermoelectric device to the heating device operates at the maximum power point.

[0012] Preferably, when performing the MPPT control, the difference between the output voltage V of the thermoelectric device collected at the current moment and the voltage collected at the previous moment is calculated to obtain dV, and the difference between the output current I of the thermoelectric device collected at the current moment and the current collected at the previous moment is calculated to obtain dI, and the addition result of dI / dV and I / V is calculated; it is judged whether the addition result is greater than 0.01. If so, the output voltage of the thermoelectric device is increased; if the addition result is less than 0.01, the output voltage of the thermoelectric device is decreased; if the addition result is between -0.01 and 0.01, no adjustment is made.

[0013] Preferably, the method further includes: after the output voltage of the thermoelectric device passes through voltage stabilization control, it is then output to the heating device.

[0014] Preferably, the working time T required by the thermoelectric device is determined according to the following formula:

[0015]

[0016] wherein, U is the voltage output from the thermoelectric device to the heating device, I is the current output from the thermoelectric device to the heating device, U B is the battery voltage, I B is the battery current,U j is the voltage required for the heating device, I j is the current required for the heating device;

[0017] For T 1, T 2, T 3, start timing after the battery starts supplying power, T 1 is the independent working time of the battery in the first stage, T 2 is the time when the battery current decreases to 0, T 3 is the time when the output power of the thermoelectric device is stable.

[0018] Preferably, when the output current of the thermoelectric device in the combined heat and power supply system decreases, the battery starts to intervene in power supply.

[0019] The present invention also provides a combined heat and power supply system and a battery dual-source parallel self-balancing power supply device for supplying power to a heating device in a vehicle; the device includes: a combined heat and power supply system, an MPPT algorithm controller, an output adjustment circuit, a voltage stabilizing module, a battery, a switch, and a detection and control module;

[0020] The electric energy output end of the thermoelectric device of the combined heat and power supply system is connected to the MPPT algorithm controller and the output adjustment circuit, and the output adjustment circuit is connected to the voltage stabilizing module; the output end of the voltage stabilizing module is connected in parallel with the battery to supply power to the heating device; the switch is arranged on the output line of the voltage stabilizing module to connect or disconnect the power supply of the voltage stabilizing module to the heating device;

[0021] The detection and control module is connected to the electric energy output end of the thermoelectric device, the output end of the battery, the voltage stabilizing module, the switch, and the heating device, and is used to control the operation of the self-balancing power supply device; the operation includes a first stage and a second stage;

[0022] In the first stage, the detection and control module controls the switch to be disconnected, and the battery supplies power to the heating device alone; the high-temperature gas discharged from the heating device is introduced into the combined heat and power supply system, and the thermoelectric device of the combined heat and power supply system converts heat energy into electric energy for output; when the detection and control module detects that the output voltage of the voltage stabilizing module reaches the voltage required for the heating device, it controls the switch to be closed and transfers to the second stage;

[0023] In the second stage, the thermoelectric device and the battery are connected in parallel to supply power to the heating device; the MPPT algorithm controller performs maximum power point tracking on the output voltage of the thermoelectric device. The MPPT algorithm controller controls the output adjustment circuit to make the electric energy output from the thermoelectric device to the heating device operate at the maximum power point, and then loads it to the heating device through the voltage stabilization module; as the heat of the high-temperature gas discharged by the heating device increases, the output current of the thermoelectric device increases and gradually replaces the parallel-connected battery; when the output current of the battery gradually decreases to 0, the thermoelectric device starts to charge the battery while supplying power to the heating device; the detection and control module calculates the working time required for the thermoelectric device to compensate for the power consumption of the battery in the first stage while supplying power to the heating device according to the changes in the output voltage and current of the battery and the thermoelectric device. T ; After the working time of the thermoelectric device reaches T , the control heating device stops operating.

[0024] Preferably, the detection and control module calculates the working time required for the thermoelectric device using the following formula T :

[0025]

[0026] where U is the voltage output from the thermoelectric device to the heating device, I is the current output from the thermoelectric device to the heating device, U B is the battery voltage, I B is the battery current, U j is the voltage required by the heating device, I j is the current required by the heating device; for T 1, T 2, T 3, timing starts after the battery starts supplying power, T 1 is the independent working time of the battery in the first stage, T 2 is the time when the battery current decreases to 0, T 3 is the time when the output power of the thermoelectric device is stable.

[0027] Preferably, the output adjustment circuit adopts a buck circuit, and the MPPT algorithm controller realizes the adjustment of the output voltage of the thermoelectric device by controlling the duty cycle of the buck circuit;

[0028] When the MPPT algorithm controller performs MPPT control, it calculates the difference dV between the output voltage V of the thermoelectric device collected at the current moment and the voltage collected at the previous moment, and calculates the difference dI between the output current I of the thermoelectric device collected at the current moment and the current collected at the previous moment, and calculates the sum of dI / dV and I / V; it determines whether the sum is greater than 0.01. If it is, the output voltage of the thermoelectric device is increased; if the sum is less than 0.01, the output voltage of the thermoelectric device is decreased; if the sum is between -0.01 and 0.01, no adjustment is made.

[0029] Advantageous effects:

[0030] (1) A thermoelectric-battery dual-source parallel self-balancing power supply method for a cogeneration system disclosed by the present invention, by paralleling the cogeneration system with the battery. After the battery works for a period of time at the beginning stage, the cogeneration system gradually replaces the battery to start power supply. While meeting the power consumption requirements of the heating system, it can charge the battery, making up for the previous consumption of the battery and reserving energy for the next use.

[0031] (2) A thermoelectric-battery dual-source parallel self-balancing power supply method for a cogeneration system disclosed by the present invention, after introducing the cogeneration system into the heating device, reduces the waste of thermal energy caused by using the heating device, and at the same time makes up for the disadvantage of the poor performance of the battery at low temperatures.

[0032] (3) A thermoelectric-battery dual-source parallel self-balancing power supply method for a cogeneration system disclosed by the present invention, by paralleling the cogeneration system with the battery, directly converts thermal energy into electrical energy, without the need to additionally supplement electrical energy, and realizes the self-balancing power supply of the heating device.

[0033] (4) To solve the problems of small output power and low output efficiency of the cogeneration system, after the output of the cogeneration system is introduced into the controller, the MPPT control method is adopted to stabilize the output power of the cogeneration system near its maximum power point, improving the output performance of the cogeneration system. Description of the drawings

[0034] Figure 1 It is a schematic diagram of the thermoelectric-battery dual-source parallel self-balancing power supply scheme of the cogeneration system of the present invention;

[0035] Figure 2 It is a schematic diagram of the composition of the thermoelectric-battery dual-source parallel self-balancing power supply device in the preferred embodiment of the present invention;

[0036] Figure 3 It is a schematic diagram of the electrical energy change of a thermoelectric-battery dual-source parallel self-balancing power supply method for a cogeneration system disclosed by the present invention;

[0037] Figure 4 It is the P-V curve diagram of the thermoelectric sheet array. Specific implementation mode

[0038] The present invention will be described in detail below with reference to the accompanying drawings and by way of examples.

[0039] The present invention provides a combined heat and power system-battery dual-source parallel self-balancing power supply scheme, in which the combined heat and power system and the battery are connected in parallel to supply power to the heating device in the vehicle. As Figure 1 shown, this scheme is divided into two stages:

[0040] Stage 1: First, use the battery to supply power to the heating device to make it start working, and then introduce the high-temperature gas provided by the heating device into the combined heat and power system, and the thermoelectric device directly converts the thermal energy into electrical energy output; when the output voltage of the combined heat and power system reaches the voltage required by the heating device, it enters Stage 2;

[0041] Stage 2: The thermoelectric device and the battery are connected in parallel to supply power to the heating device. As the output current of the thermoelectric device increases, the output current of the thermoelectric device increases and gradually replaces the parallel-connected battery; when the output current of the battery gradually decreases to 0, while the thermoelectric device is supplying power to the heating device, it starts to charge the battery in reverse. According to the changes in the output voltage and current of the battery and the thermoelectric device, calculate the working time required for the thermoelectric device to compensate for the power consumption of the battery in Stage 1 while supplying power to the heating device T ; after the working time of the thermoelectric device reaches T , stop the thermoelectric device and the battery from supplying power to the heating device, and the heating device stops running. Before reaching the working time T , if the output electric energy of the combined heat and power system is insufficient to support the power consumption of the heating device for some reason, the battery starts to intervene in power supply to achieve dual-source parallel self-balancing power supply.

[0042] Figure 2 shows the schematic diagram of the combined heat and power system-battery dual-source parallel self-balancing power supply method in the preferred embodiment of the present invention. This diagram can also be regarded as the block diagram of the combined heat and power system-battery dual-source parallel self-balancing power supply device. As Figure 2As shown in the figure, the self-balancing power supply device includes a combined heat and power generation system, an MPPT algorithm controller, an output adjustment circuit, a voltage stabilization module, a battery, a switch, and a detection and control module (not shown in the figure). As shown in the figure, the power output terminal of the thermoelectric device of the combined heat and power generation system is connected to the MPPT algorithm controller and the output adjustment circuit, and the output adjustment circuit is connected to the voltage stabilization module; after the output terminal of the voltage stabilization module is connected in parallel with the battery, it supplies power to the heating device; the switch is arranged on the output line of the voltage stabilization module to connect or cut off the power supply of the voltage stabilization module to the heating device. The detection and control module is connected to the power output terminal of the thermoelectric device, the output terminal of the battery, the voltage stabilization module, the switch, and the heating device, and is used to collect state quantities and control the operation of the self-balancing power supply device. The detection and control module includes a control computer, some control lines, and state monitoring devices. The work of the detection and control module includes: collecting voltage and current from the power output terminal of the thermoelectric device, and collecting voltage and current from the output terminal of the battery; monitoring the power of the output signal of the voltage stabilization module; controlling the opening and closing of the switch; controlling the operation of the heating device or not.

[0043] In this preferred embodiment, the output adjustment circuit adopts a buck circuit, and the MPPT algorithm controller realizes the adjustment of the output voltage of the combined heat and power generation system by controlling the duty cycle of the buck circuit.

[0044] The specific implementation process of the dual-source parallel self-balancing power supply method of the combined heat and power generation system and the battery of the present invention includes the following steps:

[0045] Step 1: First, enter stage 1. The detection and control module controls the switch to disconnect. The battery starts to supply power to support the heating device to start working. The heating device discharges high-temperature gas into the collector of the combined heat and power generation system. At the same time, cooling water is introduced into the radiator of the combined heat and power generation system. The high-temperature gas and the cooling water form a temperature difference at both ends of the thermoelectric sheet, generating an electromotive force difference and outputting electric energy outward. When the battery starts to supply power, timing starts.

[0046] Step 2: Collect the voltage, current, and working duration of the electric energy output by the combined heat and power generation system described in Step 1, as well as the working voltage, working current, and working duration of the battery.

[0047] In this step, the detection and control module starts timing when the battery starts to supply power; at the same time, an oscilloscope device is used to collect the voltage and current of the combined heat and power generation system and the battery.

[0048] Step 3: For the electric energy generated by the combined heat and power generation system in Step 1, connect it to the MPPT controller, and perform maximum power point tracking control based on the DC-DC circuit.

[0049] In this step, subtract the voltage collected at the current moment from the voltage collected at the previous moment to obtain dV, subtract the current collected at the current moment from the current collected at the previous moment to obtain dI, and calculate dI / dV and I / V at this time.

[0050] Preferably, the DC-DC circuit uses a buck circuit combined with the admittance increment method to control the duty cycle. The admittance increment method is a process of self-optimization based on the Figure 4 shown output power-output voltage characteristic curve. Each control is recorded as a control cycle; in each control cycle, by adjusting the output voltage, the calculated dV / dI and I / V are added, and whether to increase or decrease the voltage is determined by judging the sign of the sum value; in this way, the output power can be adjusted to approach the maximum power point; it is adjusted and controlled with the aim of optimizing the output power; the specific method is as follows:

[0051] When the combined heat and power supply system is at the maximum power point, the relationship shown in Equation (1) holds:

[0052] (1)

[0053] If the value obtained by adding the calculated dI / dV and I / V is greater than 0.01, the input voltage of the combined heat and power supply system needs to be increased. If the value obtained by adding the calculated dI / dV and I / V is less than -0.01, the input voltage of the combined heat and power supply system needs to be decreased. If the value obtained by adding the calculated dI / dV and I / V is between -0.01 and 0.01, no operation is required. Among them, 0.01 is the preferred value determined through experiments.

[0054] The increase or decrease of the voltage of the combined heat and power supply system is achieved by adjusting the duty cycle of the buck circuit. There is a relationship shown in Equation 2 for the buck circuit. Therefore, when it is necessary to increase the input voltage, the duty cycle can be decreased in steps of 0.01, and when it is necessary to decrease the input voltage, the duty cycle can be increased in steps of 0.01.

[0055] (2)

[0056] Among them, VO is the output voltage of the buck circuit, D is the duty cycle, VI is the input voltage of the buck circuit.

[0057] Through the control of the MPPT controller, the thermoelectric device of the combined heat and power supply system outputs electrical energy and operates at the maximum power point.

[0058] Step Four: Input the output electrical energy that has passed through the MPPT controller into the voltage stabilizing module. When the output voltage of the thermoelectric device is stabilized to the voltage required by the heating device through the voltage stabilizing module, the required voltage in this embodiment is 28V, and at this time, it transfers to Stage Two.

[0059] Step 5: After entering Phase 2, the detection and control module turns on the switch between the CCHP system and the battery, enabling the CCHP system to gradually replace the battery to power the heating device. As the heat of the high-temperature gas discharged by the heating device increases, the output current of the thermoelectric device increases, and the output current of the battery gradually decreases.

[0060] Step 6: The detection and control module records the curves of the voltage and current of the CCHP system passing through the MPPT controller and the voltage regulator module over time during the process of Step 5, and simultaneously records the curves of the voltage and current of the battery over time.

[0061] In this step, an oscilloscope 1 can be used to measure the curves of the voltage and current output by the voltage regulator module over time, and an oscilloscope 2 can be used to measure the curves of the output voltage and current of the battery over time.

[0062] Step 7: As shown in the schematic diagram of the electrical energy change Figure 3 , according to the parameters of the CCHP system and the battery recorded in Step 6, calculate the specific working duration T of the CCHP system.

[0063] In this step, according to Formula 3, calculate the working time required for the CCHP system to supply power to the heating device while compensating for the power consumption of the battery in the starting stage T . In this embodiment, the calculated time is, for example, 8 min.

[0064] (3)

[0065] where U is the output voltage of the voltage regulator, I is the output current of the voltage regulator, U B is the battery voltage, I B is the battery current, T 2 is the time when the battery starts to change from the discharging state to the charging state, U j is the voltage required by the heating device, I j is the current required by the heating device. For the parameters T 1, T 2 and T 3, start timing after the battery starts to supply power and monitor the battery current and the output power of the voltage regulator module. When the voltage of the voltage regulator module reaches 28 V, record the time as T 1, T 1 is the independent working time of the battery; when the battery current decreases to zero, record the time as T2, and when the output power of the voltage regulator module is stable, record the time as T 3. The judgment of stability can be that when the change in power within 5 s is less than 0.1 W, the power can be considered stable.

[0066] In the above formula, represents the electric energy output of the combined heat and power system before the power is stabilized, represents the electric energy output of the combined heat and power system after the power is stabilized, represents the electric energy output when the battery supplies power alone before the combined heat and power system operates, represents the electric energy consumption of the battery when the combined heat and power system and the battery supply power simultaneously, represents the electric energy demand of the heating device within the working time T.

[0067] Combined with Figure 3 As shown, within the time period from the start to T1, the electric energy demand of the heating device is completely provided by the battery. Within the time period from T1 to T2, since the heating device provides heat energy for the combined heat and power system to generate electric energy, but due to the time required for heat conduction, the output electric energy gradually increases and can reach stability after a period of time. During this process, the output voltage of the voltage stabilizing module reaches 28V and the output current gradually increases, and the power supply electric energy of the battery gradually decreases and starts charging at the moment of T2. From T2 to T3, the electric energy output of the combined heat and power system continues to increase, increasing the electric energy for charging the battery. After the moment of T3, the combined heat and power system outputs stably, while supplying power to the heating device and stably charging the battery. By calculation, when the time reaches T, the combined heat and power system provides sufficient electric energy for the heating device, and the power supply to the heating device can be cut off to avoid wasting fuel. At the same time, the combined heat and power system also charges the battery, making up for the previous consumption of the battery and reserving energy for the next use.

[0068] Step Eight: According to the time T calculated in Step Seven, stop the operation of the heating device after the combined heat and power system has been operating for 8 minutes, which can enable the combined heat and power system to supply power to the heating device while making the electric energy of the battery greater than or equal to the state before use, thus realizing the self-balanced power supply of the combined heat and power system - battery dual-source parallel connection.

[0069] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in this description can be different and are not limited. Therefore, those skilled in the art of the present invention can modify or make equivalent replacements to the technical solutions recorded in the foregoing embodiments; and these modifications and replacements do not depart from the gist and technical solutions of the present invention, and shall all fall within the protection scope of the present invention.

Claims

1. A heat and power cogeneration system and a battery dual-source parallel self-balancing power supply device, used to power a heating device in a vehicle; characterized in that: The device includes: a combined heat and power system, an MPPT algorithm controller, an output adjustment circuit, a voltage stabilization module, a battery, a switch and a detection control module; The power output end of the thermoelectric device of the cogeneration system is connected to the MPPT algorithm controller and the output adjustment circuit, and the output adjustment circuit is connected to the voltage stabilizing module; the battery is connected in parallel with the heating device; the output end of the voltage stabilizing module is connected in parallel with the battery to supply power to the heating device; the switch is arranged on the line between the voltage stabilizing module and the battery to connect or cut off the power supply of the voltage stabilizing module to the battery and the heating device; The detection control module is connected to the power output end of the thermoelectric device, the output end of the battery, the voltage stabilizing module, the switch and the heating device, and is used to control the operation of the self-balancing power supply device; the operation includes phase one and phase two; In the first stage, the detection control module controls the switch to be disconnected, and the battery alone supplies power to the heating device; the high-temperature gas discharged from the heating device is introduced into the cogeneration system, and the thermoelectric device of the cogeneration system converts the thermal energy into electrical energy for output; when the detection control module detects that the output voltage of the voltage stabilizing module reaches the voltage required by the heating device, the switch is controlled to be closed, and the process enters the second stage; In stage two, the thermoelectric device and the battery are connected in parallel to supply power to the heating device; the MPPT algorithm controller tracks the maximum power point of the output voltage of the thermoelectric device, and the MPPT algorithm controller controls the output adjustment circuit so that the electric energy output by the thermoelectric device to the heating device runs at the maximum power point, and then is loaded to the heating device through the voltage stabilizing module; as the heat of the high-temperature gas discharged by the heating device increases, the output current of the thermoelectric device increases, gradually replacing the parallel battery; when the battery output current gradually decreases to 0, the thermoelectric device starts to charge the battery while supplying power to the heating device; the detection control module calculates the working time required for the thermoelectric device to satisfy the requirement of supplying power to the heating device while compensating for the power consumption of the battery in stage one according to the changes in the output voltage and current of the battery and the thermoelectric device T ; Thermoelectric device working time reaches T After that, the heating device is controlled to stop running.

2. The heat and power cogeneration system and battery dual-source parallel self-balancing power supply device according to claim 1, characterized in that: The detection control module uses the following formula to calculate the required working time of the thermoelectric device T : in, U is the voltage output from the thermoelectric device to the heating device, I is the current output from the thermoelectric device to the heating device, U B is the battery voltage, I B is the battery current, U j The voltage required for the heating device, I j The current required for the heating device; T 1. T 2. T 3. Start timing after the battery starts to supply power. T 1 is the independent working time of the battery in stage 1, T 2 is the time when the battery current decreases to 0, T 3 is the time when the output power of the thermoelectric device is stable.

3. The heat and power cogeneration system and battery dual-source parallel self-balancing power supply device according to claim 1, characterized in that: The output adjustment circuit adopts a buck circuit, and the MPPT algorithm controller adjusts the output voltage of the thermoelectric device by controlling the duty cycle of the buck circuit; When the MPPT algorithm controller performs MPPT control, the output voltage V of the thermoelectric device collected at the current moment is subtracted from the voltage collected at the previous moment to obtain dV, the output current I of the thermoelectric device collected at the current moment is subtracted from the current collected at the previous moment to obtain dI, and the addition result of dI / dV and I / V is calculated; it is determined whether the addition result is greater than 0.01, and if so, the output voltage of the thermoelectric device is increased; If the added result is less than 0.01, the output voltage of the thermoelectric device is reduced; if the added result is between -0.01 and 0.01, no adjustment is performed.

4. The heat and power cogeneration system and battery dual-source parallel self-balancing power supply device according to claim 1, characterized in that: When the output current of the thermoelectric device in the cogeneration system decreases, the battery begins to intervene to provide power.

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