A throttling refrigeration anti-frosting control system for a cold-chain warehouse

Abstract

This invention relates to the field of refrigeration technology, and more particularly to a throttling refrigeration anti-frost control system for warehouse cold chain. The technical solution includes a throttling energy conversion unit, where a micro-turbine expander drives a micro-permanent magnet generator to generate electricity; an energy distribution and storage unit, which rectifies and stabilizes electrical energy and stores it in a phase change energy storage module; an ultrasonic guided wave detection and control array, laid on the evaporator surface, which emits guided wave signals and receives reflected signals in detection mode, and emits high-frequency sound waves in excitation mode; an energy storage-type micro-circulation anti-frost execution unit, including microchannel thermal circulation pipelines and a micro-circulation pump, forming a closed loop with the phase change energy storage module; and an intelligent coordination controller, which controls the coordinated operation of each unit based on the detection signals. This invention provides energy for anti-frost by recovering throttling pressure energy, utilizes ultrasonic guided waves for online frost detection, and intervenes in the early stages of frost growth using a thermal and acoustic synergy approach, achieving low-energy consumption and low-disturbance active anti-frost control.

Claims

1. A throttling refrigeration and anti-frost control system for warehouse cold chain, characterized in that, include; The throttling and energy release conversion unit (100) includes an electronic expansion valve (101) and a micro turbine expander (102) connected in parallel. The micro turbine expander (102) is driven by refrigerant and converts the pressure energy during the throttling process into rotational mechanical energy and drives a micro permanent magnet generator (103) to generate electricity. An energy distribution and storage unit (200) is connected to the throttling and energy release conversion unit (100) and includes a rectifier and voltage regulator module (201) and a phase change energy storage module (202). The rectifier and voltage regulator module (201) rectifies and regulates the electrical energy generated by the generator and then sends it to the phase change energy storage module (202) for storage. The phase change energy storage module (202) contains a phase change material. An ultrasonic guided wave detection and control array (300) is laid on the surface of an evaporator (400) and includes multiple piezoelectric ceramic sensors / exciters. When the array is in detection mode, it emits high-frequency guided wave signals and receives reflected signals. When it is in excitation mode, it emits high-frequency sound waves. The energy storage micro-circulation defrosting execution unit (500) includes a microchannel heat circulation pipeline (501) and a micro circulation pump (502) laid on the surface of the evaporator (400). The microchannel heat circulation pipeline (501) and the phase change energy storage module (202) form a closed loop. The intelligent coordination controller (600) is connected to the throttling and energy release conversion unit (100), the energy distribution and energy storage unit (200), the ultrasonic guided wave detection and control array (300), and the energy storage microcirculation defrosting execution unit (500), respectively. It receives the detection signal from the ultrasonic guided wave detection and control array (300) and controls the energy recovery amount of the throttling and energy release conversion unit (100), the charging and discharging state of the energy distribution and energy storage unit (200), the start and stop of the energy storage microcirculation defrosting execution unit (500), and the working mode and excitation parameters of the ultrasonic guided wave detection and control array (300) according to the detection signal.

2. The throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 1, characterized in that, The intelligent coordination controller (600) adjusts the guide vane opening of the micro turbine expander (102) according to the energy state of the phase change energy storage module (202). When the phase change energy storage module (202) reaches full storage, the guide vane opening of the micro turbine expander (102) is reduced, and the excess refrigerant is throttled by the electronic expansion valve (101).

3. The throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 1, characterized in that, The micro turbine expander (102) body is provided with a heat exchange channel (104), which is connected to the phase change energy storage module (202) to introduce the frictional heat generated by the operation of the micro turbine expander (102) into the phase change energy storage module (202); the micro turbine expander (102) recovers power. The following formula is used for calculation: ;in, To improve entropy efficiency, This refers to the refrigerant mass flow rate through the turbine expander. The pressure difference between the inlet and outlet of the turbine expander. Density of the refrigerant; Frictional heat flow With recovery power and turbine efficiency satisfy: The heat stored in the phase change energy storage module (202) Calculate according to the following formula: ;in, For the quality of phase change materials, For the specific heat of phase change materials, The current temperature of the phase change material. Phase transition temperature The phase transition fraction, This is the latent heat of phase transition.

4. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 1, characterized in that, The microchannel hot circulation pipeline (501) of the energy storage microcirculation defrosting execution unit (500) is laid close to the root of the fins of the evaporator (400), and the start and stop of the micro circulation pump (502) is controlled by the intelligent coordination controller (600) according to the detection results of the ultrasonic guided wave detection and control array (300).

5. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 1, characterized in that, The intelligent coordination controller (600) performs the following control steps: Acquire the reference signal collected by the ultrasonic guided wave detection and control array (300) under frost-free conditions; The ultrasonic guided wave detection and control array (300) is activated in intermittent mode to acquire the current guided wave signal and calculate the frost layer thickness and distribution. When the frost layer thickness reaches the first preset threshold, the energy storage microcirculation anti-frost execution unit (500) is activated to perform thermal intervention; After the thermal intervention is stopped, the ultrasonic guided wave detection and control array (300) is activated again to obtain the distribution of residual frost layer; When the thickness of the residual frost layer is still higher than the first preset threshold, the excitation mode of the ultrasonic guided wave detection and control array (300) is activated to emit high-frequency sound waves for acoustic cleaning. When the frost layer thickness reaches the second preset threshold, switch to the standby defrosting mode.

6. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 5, characterized in that, The intelligent coordination controller (600) calculates the thickness of the paper according to the following formula. : ;in, This represents the amplitude attenuation of the current guided wave signal relative to the reference signal. This represents the rate of phase change of the current guided wave signal relative to the reference signal. , These are the preset calibration coefficients.

7. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 5, characterized in that, The intelligent coordination controller (600) calculates the thermal intervention time according to the following formula. : ;in, The density of the evaporator (400) wall material, For the specific heat of the evaporator (400) wall material, The effective volume of the evaporator (400) wall surface participating in heat exchange, For the desired surface temperature rise, The heat transfer coefficient between the microchannel and the wall surface. This refers to the heat exchange area between the microchannel and the wall. The fluid temperature output by the phase change energy storage module (202) is... The average wall temperature during the thermal intervention process.

8. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 5, characterized in that, The intelligent coordination controller (600) determines the maximum thickness of the residual frost layer. and residual area The frequency of the high-frequency sound waves emitted by the ultrasonic detection and control array in excitation mode is determined by fuzzy rules. and power : ;in, and This is a preset fuzzy rule function.

9. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 8, characterized in that, The first preset threshold is less than the second preset threshold, and the backup defrosting mode is hot gas bypass defrosting or electric heating defrosting.

10. A throttling refrigeration and anti-frost control system for warehouse cold chain according to claim 9, characterized in that, The intelligent coordination controller (600) also records the frost growth rate, thermal intervention time, acoustic wave action time, and energy storage unit charging and discharging cycle during each frost suppression intervention process, and dynamically optimizes the first preset threshold, the second preset threshold, and the fuzzy rule function based on the recorded data.

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