Duty Cycle Statistics Method and System for Satellite Electric Heater

Abstract

The present invention provides a method and system for statistically calculating the duty cycle of a satellite electric heater, including: setting a first time period and a second time period, where the first time period is greater than the second time period; within the first time period, detecting the on-off state of the electric heater corresponding to each second time period, and adjusting the value of a first counter according to the on-off states corresponding to multiple second time periods until the end of the first time period to obtain the final value of the first counter; calculating a second count value, where the second count value is equal to the ratio of the first time period to the second time period; and obtaining the duty cycle of the satellite electric heater according to the ratio of the final value of the first count value to the second count value.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft thermal control, and particularly relates to a method and system for statistically analyzing the duty cycle of a satellite electric heater. Background Art

[0002] When a satellite is in orbit, it faces the cold and dark cosmic environment. Necessary thermal control measures need to be taken to ensure that the on-board instruments and equipment work within a reasonable temperature range. The electric heater is a commonly used and important active thermal control means on the satellite. It is formed by thermocompression bonding a heating wire formed by chemical corrosion and insulating films on both sides into a thin film sheet, and is generally pasted on the target area to be temperature-controlled by silicone rubber.

[0003] When the temperature of the target area is lower than the expected value, the electric heater can be powered on to generate heat to increase the temperature of the target area. The on-off of the electric heater is usually autonomously controlled by the on-board software, which will power on or off the electric heater according to the difference between the current temperature and the expected temperature.

[0004] The duty cycle of the heater during operation is an important parameter of concern. It can reflect the average energy consumed by the electric heater on the satellite, and can also reflect the actual ability and margin of thermal control for temperature regulation.

[0005] Conventionally, there is only telemetry data on the switch state of the heater on the satellite, and there is a time interval of several seconds or even hundreds of seconds between each telemetry point, that is, the telemetry period. Each telemetry can only collect information at the current moment. During the interval time between these telemetry points, which belongs to the telemetry blind area, the switch state of the heater cannot be known, and thus the duty cycle of the electric heater during operation in orbit cannot be statistically analyzed.

[0006] Therefore, there is a need in the art for a method for statistically analyzing the duty cycle of a satellite electric heater, which is no longer affected by the interval time of telemetry data and can accurately statistically analyze the duty cycle of the electric heater during all time in orbit. Summary of the Invention

[0007] The purpose of the present invention is to provide a method and system for statistically analyzing the duty cycle of a satellite electric heater to solve the problem that the duty cycle of the electric heater during operation in orbit cannot be statistically analyzed.

[0008] To solve the above technical problem, the present invention provides a method for statistically analyzing the duty cycle of a satellite electric heater, including:

[0009] Setting a first time period and a second time period, where the first time period is greater than the second time period;

[0010] During the first time period, detect the switch states of the electric heaters corresponding to each of the second time periods, and adjust the value of the first counter according to the switch states corresponding to the multiple second time periods until the end of the first time period, and obtain the final value of the first counter;

[0011] Calculate a second count value, where the second count value is equal to the ratio of the first time period to the second time period;

[0012] Obtain the duty cycle of the satellite electric heater according to the ratio of the final value of the first count value to the second count value.

[0013] Optionally, in the method for counting the duty cycle of the satellite electric heater, the value of the first time period is 200 - 300 seconds, and the value of the second time period is 0.5 - 2 seconds.

[0014] Optionally, in the method for counting the duty cycle of the satellite electric heater, the initial value of the first counter is 0;

[0015] In each of the second time periods, if the switch state of the electric heater is the on state, the first counter is incremented by 1, otherwise it remains unchanged.

[0016] Optionally, in the method for counting the duty cycle of the satellite electric heater, the initial value of the first counter is the second count value;

[0017] In each of the second time periods, if the switch state of the electric heater is the on state, the first counter is decremented by 1, otherwise it remains unchanged.

[0018] Optionally, in the method for counting the duty cycle of the satellite electric heater, within each first time period, the initial value of the second counter is 0, and every time a second time period elapses, the second counter is incremented by 1;

[0019] Determine whether the first time period has ended. If so, the second counter stops counting, and the value at this time is used as the second count value, otherwise continue counting.

[0020] The present invention also provides a system for counting the duty cycle of a satellite electric heater, including:

[0021] An initialization module configured to set a first time period and a second time period, where the first time period is greater than the second time period;

[0022] The first counting module is configured to detect the switch state of the electric heater corresponding to each of the second time periods within the first time period, and adjust the value of the first counter according to the switch states corresponding to multiple second time periods until the end of the first time period, and obtain the final value of the first counter;

[0023] The second counting module is configured to calculate a second count value, where the second count value is equal to the ratio of the first time period to the second time period;

[0024] The duty cycle calculation module is configured to obtain the duty cycle of the satellite electric heater according to the ratio of the final value of the first count value and the second count value.

[0025] In the duty cycle statistics method and system of the satellite electric heater provided by the present invention, by detecting the switch state of the electric heater corresponding to each second time period within the first time period, and adjusting the value of the first counter according to the switch states corresponding to multiple second time periods, calculating the second count value equal to the ratio of the first time period to the second time period, and obtaining the duty cycle of the satellite electric heater according to the ratio of the final value of the first count value and the second count value, a duty cycle statistics method of the satellite electric heater is provided, which overcomes the defect that the traditional telemetry can only collect the information at the current moment each time, and the switch state of the heater in the telemetry blind area cannot be known, and the duty cycle of the electric heater working in orbit cannot be counted. The present invention calculates the duty cycle of the heater in the entire on-orbit time period through a calculation model, so as to evaluate the average power consumption and heating margin of the satellite thermal control system. In addition, the present invention does not occupy too much computing and storage resources, only needs to calculate and save the duty cycle within the larger time period of the first time period, and does not need to record the switch states within each smaller time period, and does not require additional resources for the existing satellite platform.

[0026] The present invention provides a method for statistically calculating the duty cycle of the on-board electric heater, by setting a statistical period and performing cumulative counting according to the switch state of the electric heater within the period, so as to statistically obtain the switch state of the electric heater in the traditional telemetry blind area, and help the designers correctly interpret the working conditions of the satellite thermal control system. Description of the Drawings

[0027] Figure 1 Schematic diagram of traditional telemetry quantity acquisition;

[0028] Figure 2 Flow chart of the method for statistically calculating the duty cycle of the on-board electric heater according to an embodiment of the present invention;

[0029] Figure 3 Statistical chart of the telemetry results of the actual on-orbit heater switch state of a certain satellite according to an embodiment of the present invention;

[0030] Figure 4 This is a statistical chart of the telemetry results of the actual duty cycle of a certain satellite's on-orbit heater in an embodiment of the present invention. Specific Embodiments

[0031] The following further elaborates in detail on the duty cycle statistical method and system for satellite electric heaters proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer based on the following description and the claims. It should be noted that the attached drawings are all in a very simplified form and use non-precise scales, solely for the purpose of conveniently and clearly assisting in explaining the objectives of the embodiments of the present invention.

[0032] In addition, unless otherwise stated, the features in different embodiments of the present invention can be combined with each other. For example, a certain feature in the second embodiment can be used to replace the corresponding or functionally identical or similar feature in the first embodiment, and the resulting embodiment also falls within the scope of disclosure or the scope of recording of this application.

[0033] The core idea of the present invention is to provide a duty cycle statistical method and system for satellite electric heaters to solve the problem of being unable to statistically calculate the duty cycle of the on-orbit operation of electric heaters.

[0034] To achieve the above idea, the present invention provides a duty cycle statistical method and system for satellite electric heaters, including: an initialization module configured to set a first time period and a second time period, the first time period being greater than the second time period; a first counting module configured to detect the on-off state of the electric heater corresponding to each second time period within the first time period and adjust the value of a first counter according to the on-off states corresponding to multiple second time periods until the end of the first time period to obtain the final value of the first counter; a second counting module configured to calculate a second count value, the second count value being equal to the ratio of the first time period to the second time period; a duty cycle calculation module configured to obtain the duty cycle of the satellite electric heater according to the ratio of the final value of the first count value and the second count value.

[0035] In an embodiment of the present invention, the software on the satellite automatically starts to statistically calculate the duty cycle of the electric heater, and the initial values of the time variable t (the initial value of the second counter) and the counting variable n (the initial value of the first counter) are both set to 0. The first time period is set to 256 seconds, and the second time period is set to 1 second. Those skilled in the art can set the above initial values and set values according to actual needs, which will not be elaborated here.

[0036] Furthermore, the on-off state of the corresponding heating circuit is determined every 1 s (the second time period).

[0037] If the heating circuit is in the off state at this time, then t = t + 1, n = n,

[0038] If the heating circuit is in the on state at this time, then t = t + 1, n = n + 1,

[0039] Further, the cycle time is judged. Here, the cycle period of 256 s is taken as an example (this value can be changed according to actual requirements),

[0040] When t < 256 (the first time period), it returns to the judgment of the heating circuit switch state,

[0041] When t ≥ 256, the value of n is used as an output holding quantity and enters the next statistical cycle,

[0042] Further, the value of the cumulative count n (the final value of the first counter) is divided by 256 (the second count value), and the duty cycle of the heater in the most recent statistical cycle is obtained.

[0043] In another embodiment of the present invention, the initial value of the counting variable n (the initial value of the first counter) can be set to 256, and other setting values and initial values are the same as those in the previous embodiment. The switch state of the corresponding heating circuit is judged every 1 s (the second time period),

[0044] If the heating circuit is in the off state at this time, then t = t + 1, n = n - 1,

[0045] If the heating circuit is in the on state at this time, then t = t + 1, n = n,

[0046] Further, the cycle time is judged. Here, the cycle period of 256 s is taken as an example (this value can be changed according to actual requirements),

[0047] When t < 256 (the first time period), it returns to the judgment of the heating circuit switch state,

[0048] When t ≥ 256, the value of n is used as an output holding quantity and enters the next statistical cycle,

[0049] Further, the value of the cumulative count n is divided by 256, and the duty cycle of the heater in the most recent statistical cycle is obtained. Those skilled in the art can design different counting methods according to actual needs, which will not be elaborated here.

[0050] The present invention provides a method for statistically calculating the duty cycle of a satellite electric heater. Aiming at the problem that there are time gaps in the satellite on-orbit telemetry data points and they cannot represent the state of the electric heater in the full time period, a method for statistically calculating the duty cycle is designed, so that the working conditions of the electric heater in the whole process can be obtained, helping designers reasonably judge the on-board state.

[0051] When the satellite is in orbit, data on the satellite is transmitted to the ground through telemetry. Due to limitations in tracking and control capabilities and data volume, there is usually a time interval between each telemetry measurement, that is, the telemetry cycle.

[0052] Figure 1 The following shows a schematic diagram of traditional telemetry measurement acquisition. The traditional method can only acquire the current status at certain points, and there are a large number of acquisition blind spots within the time range between the acquisition points. Moreover, the actions of the heating circuit switches within the blind spots will not be recorded, and the information within the blind spots will be lost forever.

[0053] Figure 2 The following is a schematic flow diagram of a method for statistically calculating the duty cycle of an on-board electric heater according to the present invention. In this method, a statistical period is set. Taking 256 s as an example, a cyclic statistics is performed every 256 s. Two variables are set during the statistics, namely time t and cumulative count n.

[0054] Step 101: Set the initial states of t and n to zero.

[0055] Step 102: Determine the current status of the heating circuit. If the heating circuit is in the off state at this time, then t = t + 1, n = n; if the heating circuit is in the on state at this time, then t = t + 1, n = n + 1.

[0056] Step 105: Perform a time judgment. If the time is less than the set cyclic statistics period, return to Step 102 to continue determining the status of the heating circuit in the next second. If the time is greater than or equal to the set cyclic statistics period, then use the value of n as an output holding quantity, divide the value of the cumulative count n by 256, that is, obtain the duty cycle of the heater operation within the most recent statistical period. And enter the next statistical cycle, clearing t and n.

[0057] Figure 3 、 Figure 4 The following are the actual on-orbit telemetry results of the same heating circuit on a certain satellite during the same time period. Among them Figure 3 are the telemetry results of the traditional switch status, Figure 4 are the duty cycle statistical telemetry results using the present invention during the same time period.

[0058] Figure 3 The results in show that during this time period, the heating circuit seemingly has been in the off state all the time. However, since the discrete telemetry acquisition points cannot represent the working conditions of the entire period, the judgment that it has been in the off state all the time is inaccurate.

[0059] Figure 4The statistical telemetry of the medium duty cycle shows that there are a large number of on - states in the heating circuit during the same time period, and the maximum duty cycle even reaches 60%, which is the real in - orbit actual situation.

[0060] The comparison of actual in - orbit data shows that a statistical method for the duty cycle of the on - board electric heater designed by the present invention can effectively calculate the usage of the on - board electric heater, helping designers more accurately judge the actual in - orbit state of the current satellite thermal control system.

[0061] In summary, the above - mentioned embodiments have described in detail different configurations of the duty - cycle statistical method and system for satellite electric heaters. Of course, the present invention includes but is not limited to the configurations listed in the above embodiments. Any content obtained by transformation based on the configurations provided in the above embodiments belongs to the scope protected by the present invention. Those skilled in the art can draw inferences by analogy based on the content of the above embodiments.

[0062] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0063] The above description is only a description of the preferred embodiments of the present invention and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the art of the present invention based on the above disclosure belong to the scope of protection of the claims.

Claims

1. A method for statistically calculating the duty cycle of a satellite electric heater, characterized in that, Comprising: Set a first time period and a second time period, where the first time period is greater than the second time period; Within the first time period, detect the switch state of the electric heater corresponding to each second time period, and adjust the value of the first counter according to the switch states corresponding to multiple second time periods until the end of the first time period, obtain the final value of the first counter, and take the final value of the first counter as the output retention quantity; Calculate a second count value, where the second count value is equal to the ratio of the first time period to the second time period; Obtain the duty cycle of the satellite electric heater according to the ratio of the final value of the first counter to the second count value; Wherein the software on the satellite automatically starts to count the duty cycle of the electric heater, and the first time period includes an acquisition blind area, where only the duty cycle within the first time period is calculated and saved, and the switch states within smaller time periods are not recorded, where the duty cycle of the heater is counted over the entire on-orbit time period, and where the duty cycle is sent from the satellite to the ground via telemetry.

2. The duty cycle statistical method of the satellite electric heater according to claim 1, wherein The value of the first time period is 200 - 300 seconds, and the value of the second time period is 0.5 - 2 seconds.

3. The duty cycle statistical method of the satellite electric heater according to claim 1, characterized in that, The initial value of the first counter is 0; In each second time period, if the switch state of the electric heater is in the on state, the first counter is incremented by 1, otherwise it remains unchanged.

4. The duty cycle statistical method of the satellite electric heater according to claim 1, characterized in that The initial value of the first counter is the second count value; In each second time period, if the switch state of the electric heater is in the on state, the first counter is decremented by 1, otherwise it remains unchanged.

5. The duty cycle statistical method of the satellite electric heater according to claim 1, characterized in that, Within each first time period, the initial value of the second counter is 0, and every time a second time period passes, the second counter is incremented by 1; Determine whether the first time period has ended. If so, the second counter stops counting, and the value at this time is taken as the second count value, otherwise continue counting.

6. A duty cycle statistical system for a satellite electric heater, characterized in that Comprising: An initialization module configured to set a first time period and a second time period, where the first time period is greater than the second time period; A first counting module configured to, within the first time period, detect the switch state of the electric heater corresponding to each second time period, and adjust the value of the first counter according to the switch states corresponding to multiple second time periods until the end of the first time period, and obtain the final value of the first counter; A second counting module configured to calculate a second count value, where the second count value is equal to the ratio of the first time period to the second time period; A duty cycle calculation module configured to obtain the duty cycle of the satellite electric heater according to the ratio of the final value of the first counter to the second count value; Wherein the software on the satellite automatically starts to count the duty cycle of the electric heater, and the first time period includes an acquisition blind area, where only the duty cycle within the first time period is calculated and saved, and the switch states within the second time period are not recorded, where the duty cycle of the heater is counted over the entire on-orbit time period, and where the duty cycle is sent from the satellite to the ground via telemetry.

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