System and Method for Optimizing Energy Harvesting via Attitude Control Considering Satellite Thermal Lag Characteristics

Abstract

The present invention is an energy harvesting optimization attitude control system comprising: a data collection unit that collects voltage signals from thermoelectric power generation elements disposed at multiple points on the outer shell of a satellite; a virtual sensing and attitude estimation unit that estimates the solar incidence angle based on the intensity distribution of the collected voltage signals; a future power generation prediction unit that predicts the future total power generation amount according to changes in the attitude angle of the satellite using the output characteristics of the solar panel and a thermal delay model of the insulation material containing the thermoelectric power generation elements; and an optimal target attitude calculator that calculates an optimal target attitude at which the predicted total power generation amount is maximized and maneuvers the satellite.

Description

Technology Field

[0001] The present invention relates to an attitude control system and method for optimizing energy harvesting by considering the thermal delay characteristics of a satellite. More specifically, the present invention relates to an attitude control system and method that actively optimizes an integrated energy balance by integrating the thermal inertia and power generation characteristics of a thermoelectric power generation element integrated into the multilayer insulation (MLI) of the satellite skin as state variables of an attitude control algorithm, thereby considering both the immediate power generation response of the solar panels and the delayed response of the thermoelectric power generation. Background Technology

[0002] Modern satellite systems are facing a continuous increase in power demand due to the increasing complexity of missions and the sophistication of onboard software. Generally, satellites utilize photovoltaic panels as the sole means of active power generation, and the Attitude Control System (ADCS) performs sun-pointing control to align the normal vectors of sunlight and panels in order to maximize power generation efficiency. However, considering the unique characteristics of the space environment, this traditional attitude control method entails the following fundamental technical limitations and inefficiencies.

[0003] Satellites experience extreme temperature fluctuations in space. Surfaces exposed to direct sunlight heat up to high temperatures, while shaded surfaces or those facing deep space maintain extremely low temperatures. Although Multilayer Insulation (MLI) is used to block these massive internal and external temperature gradients, conventional technology has limited its role to that of a simple passive insulator. Recently, there have been attempts to harvest energy by embedding Thermoelectric Generators (TEGs) within the MLI; however, this remains merely a hardware component for generating auxiliary power and has not reached the level required to optimize the overall system's energy balance in conjunction with the satellite's active attitude maneuvers. Consequently, the thermodynamic energy of the satellite envelope is being disregarded from the perspective of power management.

[0004] Furthermore, there is a problem regarding the inconsistency in the response characteristics of different energy sources. Power generation from solar panels responds immediately to changes in the satellite's attitude. In contrast, power generation through thermoelectric elements integrated into the insulation exhibits thermal lag; due to the thermal capacity and conductivity of the insulation itself, it takes a certain amount of time after an attitude change to reach thermal equilibrium and produce maximum output. While an attitude facing the sun directly may be advantageous for immediate solar power generation, it may not be optimal in terms of integrated energy harvesting after a certain period, considering the thermal inertia of the insulation. Since existing attitude control algorithms cannot predict these changes in thermal state in the time domain, they have limitations in maximizing the total available energy.

[0005] Furthermore, in emergency situations where the satellite enters the eclipse phase or the State of Charge (SoC) rapidly deteriorates, existing systems are limited to a passive response of shutting down mission equipment. If the attitude control system could strategically utilize the thermal energy accumulated in the insulation—that is, by maneuvering to an attitude that preemptively maximizes the temperature difference of the insulation before entering the eclipse phase—additional emergency power could be secured. However, current ADCS logic lacks an intelligent optimization engine capable of resolving the trade-off between aiming precision and energy harvesting in real time.

[0006] Therefore, there is an urgent need for a new dimension of intelligent attitude control technology that moves away from the method of tracking a fixed point, integrates the satellite's thermal inertia model into the control loop, and derives the optimal attitude by predicting the integrated energy at a future point in time. Prior art literature

[0007] Japanese Registered Patent JP7204987B Orbit attitude control device, artificial satellite, orbit attitude control method and program The problem to be solved

[0008] The present invention aims to provide a system and method for controlling maneuvering by analyzing a plurality of thermoelectric power generation signals placed on the surface of a satellite to model the thermal state of the satellite, and deriving the optimal attitude of the satellite based on an objective function that integrates the immediate response of photovoltaic power generation and the delayed response of thermoelectric power generation.

[0009] The present invention aims to maintain the attitude of a satellite even when the optical sensor is obscured or malfunctions by inversely estimating the solar vector from the thermoelectric voltage distribution of each face and utilizing it as an auxiliary input for attitude control.

[0010] In addition, the present invention aims to maximize the integrated energy harvest at a future point in time by integrating the transient power until thermal equilibrium is reached after attitude maneuvering through model predictive control applying a thermal delay model of the insulation material. Furthermore, the present invention aims to secure an emergency power source by preemptively maneuvering the satellite into an attitude that maximizes the temperature gradient of the insulation material before the time of entering the eclipse interval.

[0011] Therefore, it is necessary to resolve the problems of conventional technology, which cannot utilize the thermodynamic energy of the satellite envelope, cannot manage multiple energy sources with different response characteristics integrally, and cannot strategically utilize accumulated thermal energy in the event of a power crisis. means of solving the problem

[0012] An energy harvesting optimization attitude control system according to the present invention for solving the above problems comprises: a data collection unit that collects voltage signals from thermoelectric power generation elements disposed at multiple points on the outer shell of a satellite; a virtual sensing and attitude estimation unit that estimates the solar incidence angle based on the intensity distribution of the collected voltage signals; a future power generation prediction unit that predicts the future total power generation amount according to the change in the attitude angle of the satellite using the output characteristics of the solar panel and a thermal delay model of the insulation material containing the thermoelectric power generation elements; and an optimal target attitude calculator that calculates the optimal target attitude at which the predicted total power generation amount is maximized and maneuvers the satellite. The optimal target attitude calculator varies the priority weights between power sources in real time based on battery remaining capacity information, the future power generation prediction unit integrates transient state power in the time domain using a model prediction control algorithm, and the virtual sensing and attitude estimation unit converts a virtual solar vector into a feedback signal in the event of a malfunction of the optical solar sensor.

[0013] The energy harvesting optimization attitude control system of the present invention comprises: a data collection unit that collects voltage signals from a thermoelectric power generation element integrated into a multilayer insulation material of a satellite shell; a future power generation prediction unit that predicts the time when the satellite enters an eclipse interval and the accumulated thermal energy available during the eclipse interval based on the satellite's orbit information and a thermal delay model of the insulation material; and an optimal target attitude calculator that secures an emergency power source by preemptively maneuvering the satellite to a target attitude where the temperature gradient of the insulation material is maximized prior to the time of entry into the eclipse interval.

[0014] The energy harvesting optimization attitude control method of the present invention comprises the steps of: collecting voltage signals from thermoelectric power generation elements disposed at multiple points on the outer shell of a satellite; estimating the solar incidence angle based on the intensity distribution of the collected voltage signals; predicting the future total power generation amount according to the change in the attitude angle of the satellite using the output characteristics of the solar panel and a thermal delay model of the insulation material containing the thermoelectric power generation elements; and calculating an optimal target attitude that maximizes the predicted total power generation amount and operating the satellite.

[0015] The energy harvesting optimization attitude control method of the present invention comprises the steps of: predicting the time when a satellite enters an eclipse interval based on orbit information of the satellite and a thermal delay model of a thermoelectric power generation element integrated into a multilayer insulation material; calculating a target attitude in which the temperature gradient of the insulation material is maximized prior to the time of entry into the eclipse interval; and preemptively maneuvering the satellite to the target attitude to secure an emergency power source. Effects of the invention

[0016] According to the present invention, the satellite moves away from simple attitude control that follows light and performs active energy management that considers the thermal inertia of the entire satellite. This enables preemptive energy acquisition before entering the eclipse interval and maximizes the total available energy at a future point in time by integrating photovoltaic power generation and thermoelectric power generation, which have different response characteristics, into a single objective function.

[0017] Furthermore, the present invention dramatically improves satellite survivability by maintaining attitude through a virtual solar vector inversely estimated from thermoelectric signals, even when the optical solar sensor is obscured or malfunctions. Consequently, the present invention resolves the trade-off between aiming precision and energy harvesting in real time, thereby achieving a longer mission life and higher mission availability with the same hardware resources. Brief explanation of the drawing

[0018] FIG. 1 is a block diagram illustrating the main components and mutual data flow of an energy harvesting optimization attitude control system according to the present invention. Figure 2 is a flowchart showing the process of calculating the optimal target attitude and maneuvering the satellite by considering the thermal delay characteristics of the multilayer insulation material. Specific details for implementing the invention

[0019] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0020] FIG. 1 is a block diagram illustrating the main components and mutual data flow of an energy harvesting optimization attitude control system according to the present invention.

[0021] Referring to FIG. 1, an energy harvesting optimization attitude control system according to one embodiment of the present invention comprises a data collection unit (10), a driving unit (20), and a control system (30), and these components are mounted on a satellite and exchange data with each other.

[0022] The data collection unit (10) is configured to collect basic data for determining the available energy and thermal state of the satellite, and receives solar panel power generation data (10-1), battery SoC information (10-2), and MLI integrated thermoelectric element signal (10-3). The solar panel power generation data (10-1) indicates the amount of immediate power generated by the solar panels installed on the satellite in the current attitude. The battery SoC information (10-2) indicates the remaining charge status of the battery mounted on the satellite and is used as a criterion by the control system (30), described later, to determine priority weights between power sources. The MLI integrated thermoelectric element signal (10-3) is a voltage signal output by a plurality of thermoelectric power generation elements integrated inside the multilayer insulation material of the satellite shell, and has a value proportional to the magnitude of the temperature gradient measured on each surface.

[0023] The drive unit (20) is configured to apply torque to the satellite to achieve a target attitude calculated by the control system (30). The drive unit (20) includes a reaction wheel / torker (20-1) and performs satellite maneuvering (20-2) through the rotation of the reaction wheel / torker (20-1) or the generation of magnetic torque. Satellite maneuvering (20-2) refers to an operation that changes the attitude angle of the satellite from the current attitude to the target attitude.

[0024] The control system (30) is an ADCS responsible for determining and controlling the attitude of the satellite and includes a virtual sensing and attitude estimation unit (30-1), an optimal target attitude calculator (30-2), and a future power generation prediction unit (30-3).

[0025] The virtual sensing and attitude estimation unit (30-1) estimates the solar incidence angle by analyzing the intensity distribution of the MLI integrated thermoelectric element signal (10-3) collected by the data collection unit (10). Since each face of the satellite shell forms a different temperature gradient depending on the degree to which it faces the sun, the solar vector can be inversely estimated from the thermoelectric voltage distribution of each face. The virtual sensing and attitude estimation unit (30-1) utilizes the inversely estimated solar vector as an auxiliary input for attitude control, i.e., a virtual sensor signal. In particular, if the signal of the optical solar sensor is obscured or malfunctions, the virtual sensing and attitude estimation unit (30-1) converts the virtual solar vector calculated based on the voltage pattern of the thermoelectric power generation element into a feedback signal for the attitude control loop, so that the satellite maintains its attitude even in the event of a sensor failure.

[0026] The future power generation prediction unit (30-3) predicts the total amount of accumulated energy that the current attitude operation will generate during a specific time interval in the future by utilizing the output characteristics of the solar panel and the thermal lag model of the multilayer insulation material. While power generation by the solar panel responds immediately to the change in attitude, power generation by the thermoelectric power generation element integrated into the multilayer insulation material reaches thermal equilibrium and produces maximum output only after a certain amount of time has elapsed since the change in attitude due to the thermal capacity and thermal conductivity characteristics of the insulation material itself. The future power generation prediction unit (30-3) calculates the temporal change of the temperature gradient from the time of the change in attitude to the time of reaching thermal equilibrium by applying a thermal lag model based on a heat transfer equation that includes the thermal capacity and thermal conductivity coefficient of the insulation material. The future power generation prediction unit (30-3) uses a Model Predictive Control (MPC) algorithm to integrate the transient state power from the time of the change in attitude until thermal equilibrium is reached in the time domain, and thereby predicts the future total power generation by summing the immediate power generation and the delayed power generation.

[0027] The objective function (J) calculated by the future power generation prediction unit (30-3) is expressed by the following mathematical formula 1.

[0028]

[0030] In Equation 1, J is the objective function for evaluating the superiority or inferiority of candidate attitudes, t is the current time, and T is the length of the prediction interval. θ represents the attitude of the satellite, i.e., the angle of solar incidence, and Δ represents the temperature difference between the two sides of the multilayer insulation. P_PV(θ) is the power generation of the solar panel and responds immediately to attitude θ. P_TEG(Δθ) is the power generation of the thermoelectric generator and depends not only on attitude θ but also on the temperature difference Δ. Since the temperature difference Δ changes over time according to the heat transfer equation after the attitude change, it has a thermal lag characteristic in which the output varies over time even at the same attitude. w1 and w2 are weights assigned to the power generation of the solar panel and the power generation of the thermoelectric generator, respectively, and are values ​​that vary according to the power state of the satellite.

[0031] As shown in Equation 1, the objective function (J) is defined as the value obtained by integrating the accumulated energy from the current time t to the prediction interval T in the time domain, rather than the instantaneous power generation. This is because the instantaneous power generation of the solar panel and the delayed power generation of the thermoelectric power generation element have different time response characteristics. Although an orientation facing the sun directly at the current time may be advantageous in terms of instantaneous power generation, a slightly tilted orientation may provide a larger total power generation in terms of the accumulated energy in the prediction interval T, considering the thermal inertia of the insulation material, and the time integral in Equation 1 quantitatively reflects this trade-off.

[0032] The optimal target attitude calculator (30-2) calculates the optimal target attitude that maximizes the future total power generation predicted by the future power generation prediction unit (30-3). The optimal target attitude calculator (30-2) defines an objective function by summing the immediate power generation of the solar panel and the delayed power generation of the thermoelectric power generation element with weights that vary according to the power state of the satellite, and determines the attitude that maximizes the objective function as the optimal target attitude. At this time, the weights vary in real time based on the battery SoC information (10-2). For example, when the remaining battery level is below a preset threshold, the optimal target attitude calculator (30-2) sets the weight assigned to the power generation of the thermoelectric power generation element higher than the weight assigned to the power generation of the solar panel, thereby determining the attitude in a direction that maximizes the temperature gradient of the insulation material.

[0033] The optimal target attitude calculator (30-2) calculates the attitude that maximizes the objective function (J) of Equation 1 as the optimal target attitude (θ). Meanwhile, if the objective function (J) is defined as a cost function corresponding to the energy deficit rather than the harvested energy, the optimal target attitude calculator (30-2) calculates the attitude that minimizes the objective function (J) as the optimal target attitude (θ), and the two definition methods are mathematically equivalent except for a difference in sign.

[0034] The weights w1 and w2 of Equation 1 are varied in real time based on battery SoC information (10-2). For example, under normal conditions, the weight w1 is set relatively large to prioritize immediate power generation by the solar panel and mission orientation. On the other hand, when the satellite is about to enter an eclipse phase or when the remaining battery level is below a preset threshold, the weight w2 is set relatively large to guide the optimal target attitude (θ) toward an attitude that maximizes the temperature difference Δ of the insulation material. Through such variable weights, the present invention adjusts the trade-off between orientation precision and energy harvesting in real time according to the power state of the satellite.

[0035] Meanwhile, the optimal target attitude calculator (30-2) predicts the time when the satellite enters the eclipse phase based on the satellite's orbit information and thermal delay model, and preemptively maneuvers the satellite to a target attitude where the temperature gradient of the multilayer insulation is maximized before the time of entry into the eclipse phase. Through this, the satellite secures additional emergency power from the thermal energy accumulated in the insulation even during the eclipse phase where solar radiation is blocked. The calculated optimal target attitude is transmitted to the drive unit (20) and is implemented by maneuvering the satellite (20-2) by the reaction wheel / torker (20-1).

[0036] Referring to FIG. 2, an energy harvesting optimization attitude control method according to one embodiment of the present invention is performed as follows. First, an attitude control loop is activated to initiate a control cycle (S10). When the control cycle is initiated, a data collection unit (10) collects an output signal of a solar panel (PV) and a voltage signal of a thermoelectric power generation element (TEG) integrated in a multilayer insulation material (S20).

[0037] Next, the control system (30) determines whether the optical solar sensor is operating normally (S30). If the optical solar sensor is determined to be normal, the virtual sensing and attitude estimation unit (30-1) fuses the optical sensor signal and the thermoelectric signal to estimate the precise attitude (S50). On the other hand, if the optical solar sensor is determined to be abnormal, the virtual sensing and attitude estimation unit (30-1) calculates a virtual solar vector based on the plane-by-plane pattern of the thermoelectric signal and uses it for attitude estimation (S40).

[0038] Once the attitude estimation is complete, the control system (30) checks the battery SoC and mission priority (S60). The confirmed battery remaining capacity and mission priority serve as criteria for determining weights between power sources in subsequent steps. Next, the future power generation prediction unit (30-3) predicts the power generation amount in the future time domain based on a thermal delay model (S70). The future power generation prediction unit (30-3) calculates an energy summation objective function by summing the predicted immediate power generation amount and the delayed power generation amount using weights that vary according to the power state confirmed in step S60 (S80).

[0039] The optimal target attitude calculator (30-2) calculates the optimal target attitude that maximizes the objective function calculated in step S80 (S90). Based on the calculated optimal target attitude, the drive unit (20) applies a torque command to the reaction wheel / torker and the CMG (Control Moment Gyro) (20-1) to perform satellite maneuvering (20-2) (S100). When the satellite maneuvering is completed, the corresponding control cycle ends, and the process returns to step S10 for the next control cycle (S110).

[0040] By repeatedly executing such a control loop, the satellite maximizes integrated energy harvesting while maintaining an optimal attitude considering thermal inertia during each control cycle.

[0041] The invention described above is not limited by the aforementioned embodiments and attached drawings, and various substitutions, modifications, and changes are possible by a person skilled in the art within the scope of the technical concept of the invention. All such substitutions, modifications, and changes should be interpreted as falling within the scope of the rights of the invention. Explanation of the symbols

[0042] 10: Data Collection Unit 10-1 : Solar Panel Power Generation Data 10-2 : Battery SoC Information 10-3 : MLI Integrated Thermoelectric Signal 20 : Drive unit 20-1: Reaction Wheel / Talker and CMG 20-2 : Satellite Maneuver 30: Control System (ADCS) 30-1 : Virtual Sensing and Attitude Estimation Unit 30-2 : Optimal Target Attitude Calculator 30-3 : Future Power Generation Prediction Section S10: Attitude control loop activation step S20: PV and TEG voltage signal acquisition step S30: Step to determine if the optical sensor is functioning normally S40: Step for calculating a virtual solar vector based on thermoelectric signal patterns S50: Optical / thermoelectric data fusion precision attitude estimation step S60: Battery SoC and Mission Priority Verification Steps S70: Future time-domain power generation prediction step based on thermal latency model S80: Energy summation objective function calculation step S90: Optimal Target Attitude Calculation Step S100: Drive unit torque command and start-up step S110: Exit / Return to next loop step

Claims

Claim 1 An energy harvesting optimized attitude control system comprising: a data collection unit (10) for collecting signals from thermoelectric power generation elements disposed at one or more points on the outer shell of the satellite; a virtual sensing and attitude estimation unit (30-1) for estimating the solar incidence angle based on the intensity distribution of the collected signals; a future power generation prediction unit (30-3) for predicting the future total power generation amount according to the change in the attitude angle of the satellite using the output characteristics of the solar panel and a thermal lag model of the insulating material containing the thermoelectric power generation elements; and an optimal target attitude calculator (30-2) for calculating the optimal target attitude at which the predicted total power generation amount is maximized and maneuvering the satellite. Claim 2 In claim 1, the energy harvesting optimization attitude control system is characterized in that the optimal target attitude calculator (30-2) calculates the optimal target attitude by varying the priority weight between the power generation amount of the solar panel and the power generation amount of the thermoelectric power generation element in real time based on the battery SoC information (10-2) of the satellite. Claim 3 In claim 1, the future power generation prediction unit (30-3) is characterized by calculating an objective function by integrating the transient state power until thermal equilibrium is reached after attitude operation using a Model Predictive Control algorithm, in the time domain, in an energy harvesting optimized attitude control system. Claim 4 In claim 1, the virtual sensing and attitude estimation unit (30-1) is characterized by converting a virtual solar vector calculated based on the voltage pattern of the thermoelectric power generation element into a feedback signal of the attitude control loop and utilizing it to calculate the optimal target attitude, in the case where the signal of the optical solar sensor is obscured or malfunctions, in an energy harvesting optimized attitude control system. Claim 5 An energy harvesting optimized attitude control system according to claim 1, wherein the thermoelectric power generation element is disposed inside a multilayer insulation material (MLI) of the satellite shell, and the data collection unit (10) collects the distribution of thermoelectric voltage generated on each surface corresponding to one or more surfaces of the multilayer insulation material. Claim 6 An energy harvesting optimization attitude control system, characterized in that, in the first paragraph, the thermal delay model of the future power generation prediction unit (30-3) is configured to calculate the temporal change of the temperature gradient from the time of attitude change to the time of reaching thermal equilibrium based on a heat transfer equation including the thermal capacity and thermal conductivity coefficient of the insulation material. Claim 7 In paragraph 2, the energy harvesting optimization attitude control system is characterized in that the optimal target attitude calculator (30-2) sets the weighting assigned to the power generation amount of the thermoelectric power generation element higher than the weighting assigned to the power generation amount of the solar panel when the battery remaining capacity (SoC) is less than a preset threshold value. Claim 8 An energy harvesting optimized attitude control system comprising: a data collection unit (10) for collecting voltage signals from a thermoelectric power generation element integrated into a multilayer insulation material of the satellite skin; a future power generation prediction unit (30-3) for predicting the time when the satellite enters an eclipse interval and the accumulated thermal energy available in the eclipse interval based on the satellite's orbit information and a thermal delay model of the insulation material; and an optimal target attitude calculator (30-2) for securing an emergency power source in the eclipse interval by preemptively maneuvering the satellite to a target attitude where the temperature gradient of the insulation material is maximized before the time of entry into the eclipse interval. Claim 9 In claim 8, the energy harvesting optimized attitude control system is characterized in that the optimal target attitude calculator (30-2) determines the target attitude to maintain power supply to the mission equipment of the satellite with power produced by the thermoelectric power generation element during the expression interval. Claim 10 In claim 8, the energy harvesting optimized attitude control system is characterized in that the optimal target attitude calculator (30-2) evaluates in real time the trade-off between attitude orientation for maximizing the temperature gradient of the insulation material and orientation precision for mission execution to correct the target attitude. Claim 11 An energy harvesting optimal attitude control method comprising: a data collection unit (10) collecting signals from thermoelectric power generation elements disposed at one or more points on the outer shell of the satellite (S20); a virtual sensing and attitude estimation unit (30-1) estimating the solar incidence angle based on the intensity distribution of the collected signals (S50); a future power generation prediction unit (30-3) predicting the future total power generation amount according to the change in the attitude angle of the satellite using the output characteristics of the solar panel and a thermal delay model of the insulating material containing the thermoelectric power generation elements (S70); and an optimal target attitude calculator (30-2) calculating the optimal target attitude in which the predicted total power generation amount is maximized and maneuvering the satellite (S90, S100). Claim 12 In claim 11, the predicting step (S70) is characterized by calculating an energy summing objective function by integrating the transient state power until thermal equilibrium is reached after attitude maneuvering using a model predictive control algorithm. Claim 13 In claim 11, the step of calculating the optimal target attitude (S90) further includes the step (S60) of checking the remaining battery capacity (SoC) and mission priority of the satellite, and is characterized by varying the priority weight between the power generation amount of the solar panel and the power generation amount of the thermoelectric power generation element according to the confirmed remaining battery capacity. Claim 14 An energy harvesting optimized attitude control method according to claim 11, further comprising a step (S30) of determining whether the optical solar sensor is normal prior to the step (S50) of estimating the solar incidence angle, and if the optical solar sensor is determined to be abnormal, a step (S40) of calculating a virtual solar vector based on the voltage pattern of the thermoelectric power generation element is performed and utilized for attitude estimation. Claim 15 In claim 11, the collecting step (S20) includes a step of collecting a thermoelectric voltage distribution per plane corresponding to one or more planes of a multilayer insulation material of a satellite shell, and the virtual sensing and attitude estimation unit (30-1) inversely estimates a solar vector from the thermoelectric voltage distribution per plane and utilizes it as an auxiliary input for attitude control, characterized in that it is an energy harvesting optimized attitude control method. Claim 16 In claim 12, the objective function is a function that sums the immediate power generation of the solar panel and the delayed power generation of the thermoelectric power generation element with weights that vary according to the power state of the satellite, and the calculating step (S90) is characterized by determining the attitude that maximizes the objective function as the optimal target attitude. Claim 17 An energy harvesting optimal attitude control method comprising: a future power generation prediction unit (30-3) predicting the time when the satellite enters an eclipse interval based on the satellite's orbit information and a thermal delay model of a thermoelectric power generation element integrated into a multilayer insulation material of the satellite's outer shell; an optimal target attitude calculator (30-2) calculating a target attitude in which the temperature gradient of the insulation material is maximized before the time when the satellite enters the eclipse interval (S90); and a driving unit (20) preemptively driving the satellite to the target attitude to secure an emergency power source in the eclipse interval (S100). Claim 18 In claim 17, the step of calculating the target attitude (S90) comprises a step of correcting the target attitude by evaluating the trade-off between orientation for maximizing the temperature gradient of the insulation material and orientation precision for mission execution. Claim 19 A system for performing attitude control of a satellite comprises: a data collection unit (10) for collecting voltage signals from thermoelectric power generation elements disposed at one or more points on the outer shell of the satellite; a future power generation prediction unit (30-3) for calculating an objective function (J) corresponding to the future total power generation amount according to the attitude (θ) of the satellite using the output characteristics of a solar panel and a thermal lag model of an insulating material containing the thermoelectric power generation elements, according to the following mathematical formula 1; and an optimal target attitude calculator (30-2) for calculating an optimal target attitude (θ) that maximizes or minimizes the objective function (J) and driving the satellite to the optimal target attitude (θ) through a driving unit (20); wherein [Mathematical Formula 1] Here, J is the objective function, t is the current time, T is the length of the prediction interval, θ is the attitude of the satellite, θ is the optimal target attitude, Δ is the temperature difference between the two sides of the insulation material, P_PV(θ is the power generation amount of the solar panel, P_TEG(Δθ is the power generation amount of the thermoelectric power generation element, and w₁ and w₂ are weights that vary according to the power state of the satellite), characterized by an energy harvesting optimization attitude control system. Claim 20 A method for controlling the attitude of a satellite comprises: a step (S20) in which a data collection unit (10) collects voltage signals from thermoelectric power generation elements disposed at multiple points on the outer shell of the satellite; a step (S70, S80) in which a future power generation prediction unit (30-3) calculates an objective function (J) according to the following mathematical formula 1 by integrating the transient state power until thermal equilibrium is reached after attitude maneuvering, using the output characteristics of the solar panel and a thermal delay model of the insulating material containing the thermoelectric power generation elements; and a step (S90) in which an optimal target attitude calculator (30-2) calculates an optimal target attitude (θ) that maximizes or minimizes the objective function (J), and a step (S100) in which a driving unit (20) maneuvers the satellite to the optimal target attitude (θ). [Mathematical Formula 1] Here, J is the objective function, t is the current time, T is the length of the prediction interval, θ is the attitude of the satellite, θ is the optimal target attitude, Δ is the temperature difference between the two sides of the insulation material, P_PV(θ is the power generation amount of the solar panel, P_TEG(Δθ is the power generation amount of the thermoelectric power generation element, and w₁ and w₂ are weights that vary according to the power state of the satellite), characterized by an energy harvesting optimization attitude control method.

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