High-precision high-isolation digital on-orbit adjustable reference circuit

Abstract

The invention discloses a high-precision high-isolation digital on-orbit adjustable reference circuit which comprises a space on-orbit self-adaptive adjusting unit, an MCU control unit, a reference control model library, a high-isolation signal transmission link unit, a digital control reconstruction circuit and a temperature sensor. The space on-orbit self-adaptive adjusting unit circuit collects external microwave signal power for grading, and the MCU outputs PWM wave output signals with corresponding duty ratios according to gears and the current temperature. And the PWM wave output signal is transmitted to the digital control reconstruction circuit and then reconstructed to obtain a reference voltage. According to the invention, high-precision and high-isolation reference control is realized, and more than 90% of extra-high voltage power supplies for vacuum devices are covered.

Description

Technical Field

[0001] This invention relates to a high-precision, high-isolation digital on-orbit adjustable reference circuit, belonging to the field of space power technology. Background Technology

[0002] Existing space power supplies, due to requirements for on-orbit size and weight, lack on-orbit adjustability. To achieve on-orbit adjustability, a reference voltage source capable of remote on-orbit control is needed. This reference source can then be adjusted to remotely control the operating state of the special power supply. Early reference sources used relied on diode regulation, which lacked on-orbit adjustability, resulting in a fixed output voltage and unchangeable load operating conditions. In recent years, an increasing number of loads have demanded on-orbit adjustability of special power supplies to enable on-orbit reconfigurability of load functions. The stability and reliability of the reference voltage determine the functional stability of the load after on-orbit reconfiguration. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a high-precision, high-isolation digital on-orbit adjustable reference circuit. Based on the temperature, the duty cycle of the PWM wave is adjusted in real time, and the reference voltage is obtained from the PWM wave to achieve high-precision reference control and output.

[0004] The technical solution of this invention is: A high-precision, high-isolation digital on-orbit adjustable reference circuit includes a space on-orbit adaptive adjustment unit, an MCU control unit, a reference control model library, a high-isolation signal transmission link unit, a digital control reconfiguration circuit, and a temperature sensor; The space on-orbit adaptive adjustment unit circuit collects external microwave signal power, divides it into levels according to the power value, and inputs the level control signal to the MCU control unit. The temperature sensor is located in the MCU control unit; The MCU control unit outputs a PWM wave output signal with a corresponding duty cycle based on the gear control signal and the current temperature collected by the temperature sensor, according to the reference control model library. The high isolation signal transmission link unit converts the PWM wave output signal into an optical signal, transmits it in the optical fiber, and then converts the optical signal into an electrical signal and sends it to the digital control reconfiguration circuit after the transmission is complete. The digital control reconfiguration circuit converts the electrical signal into a reference voltage.

[0005] Furthermore, the reference control model library contains a relationship table for temperature, number of gears, target reference voltage value, theoretical duty cycle of PWM wave output signal, and temperature compensation parameters. Based on the gear control signal and the current temperature collected by the temperature sensor, the number of gears and temperature are determined, the corresponding theoretical duty cycle of PWM wave output signal and temperature compensation parameters are obtained by looking up the table, the calibration duty cycle of PWM wave output signal is calculated, and the PWM wave output signal is output based on this duty cycle.

[0006] Further, calculate the calibration duty cycle of the PWM wave output signal:

[0007] In the formula, To calibrate the duty cycle, , For temperature compensation parameters, This represents the theoretical duty cycle.

[0008] Furthermore, the temperature compensation parameters in the relationship table are obtained through calibration experiments, specifically as follows: The MCU control unit generates a PWM wave output signal according to the gear control signal and the corresponding PWM wave output signal theoretical duty cycle. It compares the output reference voltage of the digital control reconstruction circuit with the target reference voltage value. If the two are inconsistent, it adjusts the temperature compensation parameter coefficient to make the MCU control unit output PWM wave output signals with different duty cycles until the two are consistent. The temperature compensation parameter and temperature value when the two are consistent are input into the relationship table of the reference control model library.

[0009] Furthermore, the method for obtaining the theoretical duty cycle of the PWM wave output signal is as follows: At room temperature, the MCU control unit outputs PWM wave output signals with different duty cycles each time according to the gear control signal. If the reference voltage output by the digital control reconfiguration circuit is consistent with the target reference voltage value, then the duty cycle of the previous PWM wave output signal is the theoretical duty cycle.

[0010] Furthermore, the temperature values ​​in the relational table cover a range of -15℃ to +65℃.

[0011] Furthermore, the digital control reconfiguration circuit includes a driver chip and an RLC integral filter circuit; The driver chip is used to stabilize the electrical signal output by the high isolation signal transmission link unit, and outputs a stable electrical signal with stable power and frequency to the RLC integral filter circuit. The RLC integral filter circuit converts the electrical signal into a voltage signal, which is the reference voltage.

[0012] Furthermore, the driver chip is the RHFPM4424 driver chip.

[0013] Furthermore, the digital control reconfiguration circuit is also equipped with a voltage regulator chip to ensure stable power supply to the driver chip.

[0014] Furthermore, the high-isolation signal transmission link unit includes an electro-optic converter, a photoelectric converter, and an optical fiber link; the electro-optic converter converts the PWM wave output signal into an optical signal, and the photoelectric converter converts the optical signal back into a PWM wave electrical signal.

[0015] The advantages of this invention compared to the prior art are: (1) The high-precision, high-isolation digital on-orbit adjustable reference circuit proposed in this invention collects control signals, confirms them by grade, and sends them to the input port of the MCU control unit model library for model calculation. It also achieves high-precision reference control and output through high and low temperature compensation.

[0016] (2) This invention proposes a PWM wave fiber optic transmission method based on photoelectric conversion technology to achieve high-precision, high-isolation reference control. The isolation voltage can be set through the fiber optic transmission distance, with an isolation voltage of 20kV or higher, covering more than 90% of ultra-high voltage power supplies for vacuum devices.

[0017] (3) The high-precision, high-isolation on-orbit adjustable digital reference circuit design method proposed in this invention uses an MCU control unit to apply the reference control model library calibration and compensation technology to carry out the calibration of the temperature compensation library, ensuring that the voltage drift of the digital reference is less than 10mV in the temperature range of (-15℃~+65℃). Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of a high-precision, high-isolation digital on-orbit adjustable reference circuit according to an embodiment of the present invention; Figure 2 This is a gradation curve diagram of the space-based on-orbit adaptive adjustment unit in an embodiment of the present invention; Figure 3 This is a design diagram of the benchmark control model library for an embodiment of the present invention; Figure 4 This is a graph showing the relationship between the PWM waveform calibration duty cycle and the theoretical duty cycle in the reference control model library of this invention. Figure 5 This is a schematic diagram of a high-isolation photoelectric conversion and transmission link according to an embodiment of the present invention; Figure 6This is a schematic diagram illustrating the high-precision digital reference reconstruction principle of an embodiment of the present invention. Figure 7 This is a graph showing the relationship between the duty cycle and the reference voltage in an embodiment of the present invention. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0020] This invention proposes a high-precision, high-isolation digital on-orbit adjustable reference circuit, such as... Figure 1 As shown, it includes a space-on-orbit adaptive adjustment unit, an MCU control unit, a reference control model library, a high-isolation signal transmission link unit, and a digital control reconfiguration circuit.

[0021] The space-based on-orbit adaptive adjustment unit samples and converts the front-end microwave signal into an analog quantity, identifies the front-end sampled signal, and inputs it to the MCU control unit in different ranges, such as... Figure 2 As shown, the circuit includes a detector, a filter circuit, and a proportional amplifier circuit. It converts the sampled microwave signal into a gear control signal, which is then used to select different gears in the MCU control unit.

[0022] The MCU control unit accepts the number of speed settings input from the adaptive adjustment unit circuit (the number of speed settings can be changed as needed), selects the output reference from the database, and then determines the reference output. See Table 1: Table 1. Correspondence between the number of gears, theoretical duty cycle, and target reference voltage in the database.

[0023] Benchmark control model library such as Figure 3 As shown, the settings are refined within the established reference range by transmitting the voltage signal of the marked temperature acquired by the temperature sensor to the MCU control unit. This is done using stored temperature-related compensation parameters. , Extract the parameters and substitute them into the temperature compensation function. In, such as Figure 4 As shown. The theoretical duty cycle of the PWM waveform. The parameters are linearized and calibrated, and the calibrated PWM waveform is output. The PWM waveform output frequency is 10kHz.

[0024] High-isolation signal transmission link units are high-voltage, high-isolation signal transmission links based on photoelectric conversion applications, including electro-optical converters and photoelectric converters, such as... Figure 5 As shown, the PWM wave output signal from the MCU control unit is converted into an optical signal via an electro-optical converter. The optical signal is transmitted through an optical fiber and then converted back into an electrical signal by a photoelectric converter. The PWM wave achieves isolated transmission through photoelectric signal conversion. The isolation voltage is related to the specially designed optical fiber link; this application scenario is designed with an isolation voltage of 20kV or higher. At the photoelectric conversion port, the output is a 20%–60% PWM wave electrical signal, such as… Figure 3 As shown.

[0025] In the digital control reconfiguration circuit, to enhance accuracy, an RHFPM4424 driver chip is added after the TTL level output of the photoelectric converter to increase the driving capability and adjustment accuracy of the PWM wave. An RLC integral filter circuit is designed after the driver chip to achieve high-precision digital reference reconfigurability. The key technology lies in using the RHFPM4424 driver chip to increase the output accuracy and sensitivity of the PWM wave. Simultaneously, to ensure the stability of the PWM wave and the stable power supply to the RHFPM4424, a TL1431 voltage regulator chip is selected to regulate the power supply, ensuring that the power supply stability of the RHFPM4424 meets the requirements. Figure 6 As shown.

[0026] High-precision, high-isolation, and high / low temperature digital temperature compensation were implemented to achieve high-precision reference control output. To ensure the reliability and stability of the digital reference and achieve high-precision control, reference calibration was performed at 1.5~3.9V at each temperature point, forming a reference control model library. During testing, a high-precision reference source was selected to calibrate the digitally adjustable reference, with a calibration accuracy of ±5mV. Temperature compensation parameters were designed in the MCU control unit model library. By calibrating the PWM model accuracy at different temperatures, temperature compensation under high and low temperatures was achieved. Specific temperature acquisition points were set near the reference circuit. Figure 7 As shown.

[0027] Use cases of this invention: Multimode traveling wave tube amplifiers, klystron amplifiers, and particle accelerators are all core components of payloads in novel satellite subsystems and are widely used in various new payloads. This invention can be applied to the field of operating mode control for space traveling wave tube amplifiers, klystron amplifiers, and particle accelerators.

[0028] Multi-mode traveling wave tube amplifiers, klystron amplifiers, and particle accelerators—signature products of new payload technology—are high-tech, high-value, and technologically complex, requiring a high degree of integration. Their main functions include power amplification of input microwave transmission signals and electron beam acceleration. The special power supplies used in these payloads possess high power density and on-orbit adjustability to accommodate the adjustable on-orbit functions of the traveling wave tube amplifiers, klystron amplifiers, and accelerators. Therefore, the special power supplies used in these new payloads require the application of a high-precision, high-isolation, on-orbit adjustable digital reference circuit design method described in this invention. This allows for on-orbit adaptive operation or, via ground stations, the transmission of commands to the on-orbit satellite to adjust its on-orbit functions.

[0029] The working principle of the reference circuit is as follows: First, on-orbit adaptive data acquisition is carried out to achieve on-orbit adaptive adjustment function for adjustment; Secondly, a high-precision temperature compensation based on an MCU control unit is used for compensation design, adjusting the width variation information of the PWM wave duty cycle, and converting the digital reference control signal into a 10kHz PWM wave TTL level output.

[0030] Then, a high-isolation signal transmission link based on photoelectric conversion is applied to transmit the PWM signal; Finally, by designing a high-precision digital reference reconstruction circuit, a signal with high amplitude stability and adjustable duty cycle is shaped at the digital reference terminal, converting the highly isolated PWM wave signal into a high-precision digital reference. The duty cycle signal has a linear relationship with the reference voltage, such as... Figure 7 As shown. The signal period is 100µs, and the range increment is 150ns; the reference voltage range is designed to be approximately 2.8~4.7V, with each adjustment increment being approximately 30mV, corresponding to a duty cycle of approximately 48%~80%.

[0031] The embodiments described above are merely preferred embodiments of the present invention. Ordinary variations and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-precision, high-isolation digital on-orbit adjustable reference circuit, characterized in that, It includes a space-on-orbit adaptive adjustment unit, an MCU control unit, a reference control model library, a high-isolation signal transmission link unit, a digital control reconfiguration circuit, and a temperature sensor; The space on-orbit adaptive adjustment unit circuit collects external microwave signal power, divides it into levels according to the power value, and inputs the level control signal to the MCU control unit. The temperature sensor is located in the MCU control unit; The MCU control unit outputs a PWM wave output signal with a corresponding duty cycle based on the gear control signal and the current temperature collected by the temperature sensor, according to the reference control model library. The high isolation signal transmission link unit converts the PWM wave output signal into an optical signal, transmits it in the optical fiber, and then converts the optical signal into an electrical signal and sends it to the digital control reconfiguration circuit after the transmission is complete. The digital control reconfiguration circuit converts the electrical signal into a reference voltage.

2. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 1, characterized in that, The reference control model library contains a table showing the relationship between temperature, number of gears, target reference voltage value, theoretical duty cycle of PWM wave output signal, and temperature compensation parameters. Based on the gear control signal and the current temperature collected by the temperature sensor, the number of gears and temperature are determined. The corresponding theoretical duty cycle of PWM wave output signal and temperature compensation parameters are obtained by looking up the table. The calibration duty cycle of PWM wave output signal is calculated, and the PWM wave output signal is output based on this duty cycle.

3. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 2, characterized in that, Calculate the duty cycle of the PWM wave output signal calibration: In the formula, To calibrate the duty cycle, , For temperature compensation parameters, This represents the theoretical duty cycle.

4. A high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 2 or 3, characterized in that, The temperature compensation parameters in the relational table were obtained through calibration experiments, specifically: The MCU control unit generates a PWM wave output signal according to the gear control signal and the corresponding PWM wave output signal theoretical duty cycle. It compares the output reference voltage of the digital control reconstruction circuit with the target reference voltage value. If the two are inconsistent, it adjusts the temperature compensation parameter coefficient to make the MCU control unit output PWM wave output signals with different duty cycles until the two are consistent. Input the temperature compensation parameters and temperature values ​​when the two are consistent into the relationship table of the reference control model library.

5. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 4, characterized in that, The method for obtaining the theoretical duty cycle of the PWM wave output signal is as follows: At room temperature, the MCU control unit outputs PWM wave output signals with different duty cycles each time according to the gear control signal. If the reference voltage output by the digital control reconfiguration circuit is consistent with the target reference voltage value, then the duty cycle of the previous PWM wave output signal is the theoretical duty cycle.

6. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 2, characterized in that, The temperature values ​​in the relational table cover -15℃ to +65℃.

7. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 1, characterized in that, The digital control reconfiguration circuit includes a driver chip and an RLC integral filter circuit; The driver chip is used to stabilize the electrical signal output by the high isolation signal transmission link unit, and outputs a stable electrical signal with stable power and frequency to the RLC integral filter circuit. The RLC integral filter circuit converts the electrical signal into a voltage signal, which is the reference voltage.

8. The high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 7, characterized in that, The driver chip used is the RHFPM4424 driver chip.

9. A high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 7, characterized in that, The digital control reconfiguration circuit also includes a voltage regulator chip to ensure stable power supply to the driver chip.

10. A high-precision, high-isolation digital on-orbit adjustable reference circuit according to claim 1, characterized in that, The high-isolation signal transmission link unit includes an electro-optic converter, a photoelectric converter, and an optical fiber link; the electro-optic converter converts the PWM wave output signal into an optical signal, and the photoelectric converter converts the optical signal back into a PWM wave electrical signal.

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