Temperature control method and system for new energy refrigerated vehicle

Abstract

This invention relates to the field of automatic control technology, specifically to a temperature control method and system for new energy refrigerated trucks. The system obtains the current state of charge of the power battery through a battery management system and calculates the current available total power based on the rated capacity. Combining the remaining path length, expected driving energy consumption, predicted power consumption, and static heat load for refrigeration and insulation, a range redundancy value is generated. When the refrigerated truck is identified as being in a parking refueling state and in a period of low electricity prices, a bottom-up optimization is performed based on the refueling state, condenser heat dissipation gain, original set temperature, and phase change freezing critical temperature to generate a target set temperature for the cargo compartment. During driving, the control demand weight formed by this temperature and the current temperature is written into the braking energy recovery effectiveness calibration. After the braking signal fades, the fan is triggered to operate at full load for a delayed period, thereby coordinating power demand, refrigeration load, off-peak electricity storage, and braking energy recovery utilization to reduce the risk of power depletion and cargo compartment overheating and improve temperature uniformity.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology, and in particular to a temperature control method and system for new energy refrigerated trucks. Background Technology

[0002] Traditional temperature control methods for new energy refrigerated trucks refer to the control approach for regulating the temperature of the cargo space in refrigerated trucks powered by electricity. These methods involve measuring the ambient temperature using resistance thermometers placed on the inner walls or top of the cargo compartment. The measured signal is transmitted to the onboard control terminal, which compares the current temperature with a preset target temperature range. Based on the difference, a frequency adjustment command is sent to the inverter, which drives the electric refrigeration compressor to change its operating frequency. This, along with opening or closing solenoid valves and adjusting the blower speed, alters the output of cooling capacity.

[0003] When road conditions fluctuate, traditional new energy refrigerated trucks often experience power output competing with refrigeration load for electricity due to the fixed control logic failing to dynamically balance the matching relationship between the total available battery capacity and the expected driving energy consumption. This can easily lead to serious risks such as battery depletion or cargo compartment overheating during delivery. Furthermore, traditional control methods typically do not incorporate parking recharging, peak and off-peak electricity pricing, regenerative braking, and the residual cold energy diffusion process after braking into the same control chain, resulting in insufficient off-peak electricity cold storage capacity, insufficient transient utilization of regenerated electricity, and insufficient temperature uniformity in the deep space of the cargo compartment. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a temperature control method and system for new energy refrigerated trucks.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a temperature control method for new energy refrigerated trucks, comprising the following steps: S1: Based on the current state of charge and rated capacity of the refrigerated truck's power battery, calculate the current available total power and define the range redundancy value under the current available total power. S2: Determine the upper limit of the inverter frequency of the refrigeration compressor by referring to the battery redundancy value, and constrain the operating frequency of the refrigeration compressor by the upper limit of the inverter frequency of the refrigeration compressor to generate the corresponding refrigeration compressor frequency limit curve; S3: Obtain the original set temperature of the cargo compartment and the critical temperature point of phase change freezing of the goods. Referring to the frequency limit curve of the refrigeration compressor, perform a bottom-up optimization process on the original set temperature of the cargo compartment towards the critical temperature point of phase change freezing of the goods to determine the target set temperature value of the cargo compartment. S4: Obtain the current temperature of the cargo compartment, determine the temperature control demand weight corresponding to the target set temperature value of the cargo compartment and the current temperature of the cargo compartment; during the operation of the refrigerated truck, determine the transient compensation temperature control gain of the frequency converter according to the temperature control demand weight. S5: After the transient compensation action corresponding to the transient compensation temperature control gain of the frequency converter is completed and the braking signal disappears, the fan delay dwell control is activated to force the circulating fan in the cargo compartment to run at full load and generate the cargo compartment temperature control result.

[0006] As a further aspect of the present invention, the step of obtaining S1 specifically comprises: S101: Collect the state of charge and rated capacity of the power battery and calculate the current total available power. Combine the bus discharge load to determine the power reference load. Simultaneously obtain the exhaust and suction pressure ratios of the refrigeration compressor. Compare with the standard reference pressure ratio to derive the available power ratio attenuation factor. Perform suppression processing on the power reference load to generate the attenuated power load. Calculate the refrigerant circulation pressure work equivalent using the enthalpy value and refrigerant mass flow rate under suction conditions. Superimpose it with the attenuated power load to obtain the available energy load. S102: Retrieve the remaining navigation path and road segment elevation gradient, convert the rolling resistance parameter and elevation change into work equivalent value, take into account the inverter loss of the drive motor and the mechanical transmission loss, combine the power consumption constant to map the power demand, and generate the predicted power consumption. S103: Read the predicted power consumption and the available energy load, and combine the thermal conductivity coefficient of the cargo compartment enclosure structure, the internal and external temperature difference, the surface area, and the expected arrival time to deduce the static heat load of refrigeration and insulation; subtract the predicted power consumption and the static heat load from the available energy load to obtain the redundant power, and introduce an energy conversion loss correction coefficient for calibration to generate a redundant value for the remaining power.

[0007] As a further aspect of the present invention, the step of obtaining S2 specifically comprises: S201: Calculate the ratio of the remaining power redundancy value to the preset safety benchmark threshold to obtain the redundancy power adequacy. Calculate the absolute value of temperature deviation based on the real-time temperature of the cargo compartment and the basic set temperature. Combine the redundancy power adequacy, the temperature rise variation rate of the cargo compartment thermistor, the temperature rise tolerance of the goods, and the absolute value of temperature deviation to generate the corresponding thermal power adjustment coefficient. S202: Calculate the fin surface temperature difference based on the air temperature at the evaporator return air inlet and the fin surface temperature, and calculate the transient heat exchange intensity by combining the fin surface temperature difference, surface area heat transfer coefficient and preset feedback correction factor. Correct the electronic expansion valve needle valve displacement according to the transient heat exchange intensity and convert it into the frequency conversion system duty cycle correction value. S203: Combine the duty cycle correction value of the variable frequency system and the rated variable frequency range of the refrigeration compressor to determine the initial upper limit of frequency. Using the thermal power adjustment coefficient as a constraint variable, perform an intersection mapping with the initial upper limit of frequency to construct the frequency limit curve of the refrigeration compressor. Use the frequency limit curve of the refrigeration compressor to limit the real-time operating frequency of the refrigeration compressor.

[0008] As a further aspect of the present invention, the step of obtaining S3 specifically comprises: S301: Identify the external charging pile protocol handshake signal through the energy replenishment communication interface, and establish the parking energy replenishment state when the external charging pile protocol handshake signal is identified to meet the standard protocol handshake level. Analyze the peak-valley electricity price topology of the local power supply section, obtain the electricity price range to which the current clock belongs, and determine the grid energy replenishment status index based on the electricity price range to which the current clock belongs and the parking energy replenishment state. The external power replenishment status includes the status in which the refrigerated vehicle replenishes power to the power battery through an external charging pile, external power supply, or battery swapping equipment. S302: When the power grid replenishment status index meets the off-peak electricity storage cold triggering condition, the condenser heat dissipation air volume surge action is triggered. The real-time condensation flux is calculated by integrating the condenser inlet and outlet airflow temperature difference, ambient humidity, windward heat dissipation area and real-time airflow velocity after the surge, and then compared with the factory-calibrated heat dissipation capacity to establish the condenser heat dissipation gain coefficient. S303: When the off-peak electricity storage and cooling mechanism is triggered, the descent span is calculated based on the condenser heat dissipation gain coefficient and the basic cooling step size. The candidate set temperature is obtained by subtracting the descent span from the original set temperature of the cargo compartment. The larger value between the candidate set temperature and the cargo freezing safety boundary temperature is taken as the target set temperature of the cargo compartment. If the original set temperature of the cargo compartment is lower than or equal to the boundary temperature, the cargo freezing safety boundary temperature is taken as the target set temperature value of the cargo compartment.

[0009] As a further aspect of the present invention, the step of obtaining S4 specifically comprises: S401: Calculate the temperature control deviation and generate temperature demand weight based on the current temperature of the cargo compartment and the target set temperature, analyze the brake pedal travel to define the recovery pulse boundary, perform equivalent accumulation deduction on the inverter feed charge within this wide range to obtain the initial recovery energy amplitude, and use the temperature demand weight to perform effectiveness calibration on it to generate the braking recovery energy amplitude. S402: The amplitude of the braking energy recovery is separated from the iron loss and copper loss of the motor to establish the effective shaft power share that is converted into refrigeration mechanical work. The effective shaft power share, the DC bus power supply power and the compressor torque gain mapping, and the upper limit of the bus capacitor voltage suppression are integrated to generate the refrigeration power mapping gain. S403: Based on the refrigeration power mapping gain, drive the gas-liquid separator to open the large flow return gas valve port, obtain the return gas superheat and flow step, fuse the return gas superheat and the flow step to perform inverter carrier frequency feedforward compensation, suppress the speed oscillation deviation caused by the sudden change in braking torque of the refrigeration compressor through the inverter carrier frequency feedforward compensation, and generate inverter transient compensation temperature control gain.

[0010] As a further aspect of the present invention, the acquisition step of S5 specifically comprises: S501: Capture the fading edge of the braking signal, and trigger the delay dwell mechanism after capturing the fading edge of the braking signal. Based on the exponential decay curve of the transient compensation temperature control gain of the frequency converter, calibrate the inertial stock of the refrigerant circulation flow, and calculate the residual cooling capacity maintenance time constant based on the inertial stock, the initial value of the transient compensation temperature control gain of the frequency converter, and the environmental heat transfer damping factor. S502: During the delayed residence period defined by the residual cold energy maintenance time constant, lock the internal circulation fan of the cargo compartment to the maximum speed, extract the suction pressure and convert it into saturated evaporation temperature, and combine the air mass flow rate, specific heat at constant pressure, the difference between return air and saturated evaporation temperature and the residual cold energy maintenance time constant to deduce and determine the heat exchange flux index of the evaporator. S503: Read the heat transfer flux index of the evaporator, drive the cold energy accumulated on the surface of the fins to be forced to convect and diffuse into the depth of the cargo compartment, integrate the geometric impedance of the air duct and the high-speed air volume to establish a flow field micro-element, use the heat transfer flux index to determine the heat flux, analyze the turbulence intensity and cold energy penetration depth, and generate the cargo compartment temperature control result.

[0011] The temperature control system for new energy refrigerated trucks includes: The remaining range redundancy analysis module obtains the current state of charge and rated capacity of the refrigerated truck's power battery, calculates the current available total power, and delineates the range redundancy value under the current available total power. The refrigeration compressor limit adjustment module determines the upper limit of the inverter frequency of the refrigeration compressor by referring to the redundancy value of the remaining power, and constrains the operating frequency of the refrigeration compressor by the upper limit of the inverter frequency of the refrigeration compressor, thereby generating the corresponding refrigeration compressor frequency limit curve. The pre-cooling temperature control strategy generation module obtains the original set temperature of the cargo compartment and the critical temperature point of phase change freezing of the goods. Referring to the frequency limit curve of the refrigeration compressor, it performs a bottom-up optimization process on the original set temperature of the cargo compartment to the critical temperature point of phase change freezing of the goods to determine the target set temperature value of the cargo compartment. The regenerative braking gain mapping module obtains the current temperature of the cargo compartment, determines the temperature control demand weight corresponding to the target set temperature value of the cargo compartment and the current temperature of the cargo compartment, and determines the transient compensation temperature control gain of the frequency converter based on the temperature control demand weight during the operation of the refrigerated truck. The cyclic intensity feedback adjustment module activates the fan delay dwell control after the transient compensation action corresponding to the transient compensation temperature control gain of the frequency converter is completed and the braking signal fades, forcing the circulating fan in the cargo compartment to run at full load and generating the cargo compartment temperature control result.

[0012] Compared with the prior art, the advantages and positive effects of the present invention are as follows: In this invention, the current state of charge (SOC) of the power battery is obtained through the battery management system, and the current SOC and the rated capacity of the power battery are explicitly calculated as the current available total energy, forming a continuous calculation chain between the current available total energy, predicted power consumption, static heat load for refrigeration and insulation, and the redundancy value of the remaining driving range. By constraining the upper limit of the execution frequency of the refrigeration compressor based on the redundancy value of the remaining driving range, and in conjunction with the pre-storage cold storage strategy during parking refueling and electricity price troughs, the overall energy consumption is optimized while maintaining the stability of system operation. By incorporating the temperature control demand weight formed by the target set temperature value of the cargo compartment into the validity calibration of the braking energy recovery amplitude, and converting the braking energy recovery into the transient gain of the refrigeration compressor, the fan is linked to delay and force cold air convection, eliminating local hot spots in the cargo compartment without increasing additional battery consumption, ultimately achieving the dual goals of global energy efficiency optimization and high-quality preservation of goods. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the workflow of the present invention. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0015] Please see Figure 1 This invention provides a technical solution: a temperature control method for new energy refrigerated trucks, comprising the following steps: S1: The current state of charge (SOC) and rated capacity of the power battery are obtained through the power battery management controller. The current SOC is the state data formed by the battery management controller after equalizing the remaining energy state of the cells. The rated capacity is the capacity benchmark matched with the battery pack in the refrigerated truck configuration data. After receiving the above data, the temperature control controller combines the remaining path length to the target destination and the refrigerated truck's mileage energy consumption constant to form the energy boundary under the current available total energy. The current available total energy is an energy object that is competed for by the refrigerated truck's driving energy, refrigeration energy, and auxiliary energy. It is not directly called as a separate refrigeration resource, but is first constrained by path energy consumption, heat load, and conversion loss to form a range energy redundancy value. The range energy redundancy value carries the remaining energy space available for temperature control scheduling before reaching the target destination and serves as the basic input for subsequent refrigeration compressor limit control. If the power battery message is missing, duplicated, has inconsistent verification, or has an abnormal timestamp, the temperature controller marks the message as unupdateable, continues to retain the most recently verified energy boundary state, and writes the source of the abnormality, receiving interface, and scope of impact into the operation record. The range redundancy value will be updated only after the new message passes the consistency verification.

[0016] S101: The power battery management controller acquires the current state of charge (SOC), rated capacity, and bus discharge load of the power battery. The bus discharge load is the load state object formed when the high-voltage DC bus supplies energy to the drive motor, refrigeration compressor, fan, and auxiliary electrical components, including load direction, load duration, and the type of energy-consuming end to which the load belongs. The temperature controller associates the current total available power with the bus discharge load to form a power reference load, used to express the occupancy relationship between the power battery's available energy and the currently output load. Subsequently, the refrigeration compressor discharge pressure and suction pressure are acquired. The discharge pressure comes from the refrigeration compressor discharge-side pressure detector, and the suction pressure comes from the suction-side pressure detector. After simultaneous timing verification, the two parameters form the refrigeration compressor discharge and suction pressure ratio parameters. The standard reference pressure ratio is the pressure ratio reference object stored in the refrigeration circuit under the refrigerated truck's calibration state. The standard reference deviation is the deviation category of the current pressure ratio state relative to this reference object. The available power ratio attenuation factor is the control object that suppresses the effect of refrigeration compressor pressure deviation on the battery's available energy. The temperature controller uses this factor to suppress the available energy of the power reference load, forming an attenuated power load. Next, the refrigerant thermodynamic property database is invoked, and the enthalpy attribute is retrieved based on the current suction temperature and suction pressure. Combined with the energy meaning corresponding to the refrigerant mass flow rate and enthalpy difference, the refrigerant cycle pressure work equivalent is generated. The decayed electrical load and the refrigerant cycle pressure work equivalent are then combined to obtain the usable energy load, which is transmitted to S102. If the pressure detector data cannot match, the thermodynamic property database retrieval fails, or the refrigerant flow signal is not confirmed, the temperature controller retains the previous effective pressure ratio state and marks the refrigerant cycle pressure work equivalent as pending update to prevent unconfirmed data from entering subsequent energy calculations.

[0017] S102: After reading the available energy load, the temperature controller retrieves the remaining navigation path from the navigation controller and reads the power consumption constant from the refrigerated truck energy consumption calibration storage area. The remaining navigation path carries the path length, road attributes, and path change status of the refrigerated truck from its current location to the target destination. The power consumption constant carries the driving energy consumption benchmark for the same refrigerated truck under the corresponding operating category. The road segment elevation gradient is jointly determined by the road attributes of the navigation map and the refrigerated truck's position status, used to express the impact of road longitudinal undulations on driving energy consumption; the rolling resistance parameter is jointly formed by the refrigerated truck's load status, tire operating status, and road category, used to express the impact of tires and road surface on energy consumption during driving. The temperature controller organizes the road segment elevation gradient and rolling resistance parameter into a work equivalent conversion value and continues to read the drive motor inverter loss and mechanical transmission loss. The drive motor inverter loss comes from the motor controller's operating status, and the mechanical transmission loss comes from the transmission link calibration status. The remaining navigation path, power consumption constant, work equivalent conversion value, drive motor inverter loss, and mechanical transmission loss are all incorporated into the predicted power consumption calculation stage to form the predicted power consumption. The predicted power consumption represents the energy expected to be used by the drive side before the refrigerated truck reaches its destination and is transmitted to S103 for redundancy stripping. If the navigation path is replanned, the temperature controller replaces the old path state with the new one and simultaneously updates the path update flag; if the elevation attribute does not match, the rolling resistance parameter and drive loss data are retained to continue participating in the calculation, while the elevation attribute is marked as pending verification.

[0018] S103: After reading the predicted power consumption and available energy load, the temperature controller obtains the thermal conductivity coefficients of the cargo compartment's inner and outer envelope structures, the temperature difference between the inside and outside of the cargo compartment, the surface area of ​​the envelope structure, and the arrival time. The thermal conductivity coefficients of the cargo compartment's inner and outer envelope structures are derived from the vehicle's cargo compartment structural configuration, representing the conductivity of the box insulation layer to external heat intrusion; the temperature difference between the inside and outside of the cargo compartment is provided by both the cargo compartment temperature detector and the vehicle's external ambient temperature detector, representing the driving force of heat exchange between the inside and outside of the cargo compartment; the surface area of ​​the envelope structure is derived from the vehicle's cargo compartment structural data, representing the boundary of heat exchange participation; the arrival time is derived from the path status of the navigation controller, representing the time object of the continuous action of the heat load during the remaining travel period. The temperature controller organizes the above data into a static heat load for cooling and insulation, which is the heat intrusion object that needs to be offset to maintain the temperature control state of the cargo compartment before reaching the target destination. The available energy load is used as the total available energy, first deducting the predicted power consumption, and then deducting the static heat load for cooling and insulation, forming a redundancy stripping result. The energy conversion loss correction coefficient is obtained by calibrating the energy conversion link of the power battery, inverter, refrigeration compressor motor, and auxiliary power supply, and is used to express the loss impact when energy enters the refrigeration actuator from the battery side. The temperature controller performs loss calibration on the redundancy stripping results, generates a range redundancy value, and transmits this value along with the data source identifier, path update identifier, and anomaly identifier to S2. If the heat conduction configuration is missing or the ambient temperature signal is distorted, the temperature controller will classify the static heat load into the conservative control category and output a cooling limit tightening identifier to S2.

[0019] S2: The remaining battery capacity redundancy value is compared with the preset safety benchmark rules to form a comparison state. The preset safety benchmark rules are the energy retention rules required for the refrigerated truck to complete the remaining route and maintain the temperature control safety of cold chain goods. These rules are derived from the refrigerated truck's energy management calibration area, goods temperature control files, and refrigerated truck configuration data. The comparison state does not participate in control as an isolated energy value, but rather enters the refrigeration compressor limit control together with the current temperature rise rate of the cargo compartment. The current temperature rise rate of the cargo compartment is generated by the continuous collection results of the thermistors in the cargo compartment, expressing the trend of the cargo compartment temperature changing in the upward direction. The temperature controller combines the comparison state and the temperature rise rate to generate the upper limit of the refrigeration compressor's inverter frequency. The upper limit of the frequency is the dynamic operating boundary that the refrigeration compressor controller is allowed to execute. This operating boundary is further combined with the electronic expansion valve correction, evaporator heat exchange status, and thermal power regulation coefficient to form the refrigeration compressor frequency limit curve. The frequency limit curve is passed to S3 as the refrigeration compressor frequency boundary when the parking replenishment pre-cooling strategy is generated. If the remaining battery power redundancy value carries a verification flag, the temperature controller will classify the refrigeration compressor frequency constraint into the protection category and retain the correction channel for the temperature rise variation rate of the cargo compartment on the frequency boundary.

[0020] S201: After reading the remaining battery redundancy value, the temperature controller maps this value to a preset safety baseline rule to obtain the redundancy battery adequacy. The redundancy battery adequacy is a control object expressing the current energy reserve relative to the safety baseline rule. Its source is not a single sampled data point, but a comprehensive result obtained after S1 separates path-driven consumption, static heat load, and conversion losses. The temperature controller continues to acquire the cargo compartment thermistor temperature rise variation rate, cargo temperature rise tolerance, and cargo compartment basic set temperature. The cargo temperature rise tolerance comes from the cargo temperature control file, limiting the permissible temperature deviation categories for cold chain goods during transportation; the cargo compartment basic set temperature comes from the cold chain task order or driver setting, and enters the control link after verification by the cargo file. The real-time cargo compartment temperature and the cargo compartment basic set temperature form the absolute value of temperature deviation, which expresses the degree of deviation of the current cargo compartment temperature control state from the target state. The redundancy battery adequacy, temperature rise variation rate, cargo temperature rise tolerance, and absolute value of temperature deviation all enter the power weight tuning stage to form the power weight. Power weighting expresses the adjustment tendency of cooling demand relative to endurance retention demand. The temperature controller then determines the cooling reduction safety margin based on the coupling relationship between power weighting and temperature rise variation rate, and generates a thermal power adjustment coefficient that is transmitted to S202. If the product temperature control profile cannot be matched, the product temperature rise tolerance is locked to the protection category, and the power weighting converges towards the insulation safety side.

[0021] S202: After reading the thermal power regulation coefficient, the temperature controller monitors the evaporator fin surface temperature and obtains the evaporator return air temperature. The evaporator fin surface temperature comes from the temperature detection element attached to the fin heat exchange surface, and the return air temperature comes from the evaporator return air channel detection element. After the two are aligned in the sampling sequence, they form the evaporator fin surface temperature difference, which characterizes the driving force for the release of cold energy between the return air and the fin heat exchange surface. The surface area heat transfer coefficient comes from the evaporator structure calibration and air duct configuration, and is used to express the ability of the fin surface to participate in heat exchange; the non-electrical variable control or regulation output feedback correction factor comes from the expansion valve opening, damper status, airflow path, and refrigerant status feedback, and its scope of action is limited to heat exchange intensity correction, and does not replace the power redundancy judgment and refrigeration compressor limit judgment. The temperature controller organizes the evaporator fin surface temperature difference and surface area heat transfer coefficient into the initial heat exchange intensity, and then introduces the feedback correction factor to scale the heat exchange intensity proportionally to obtain the transient heat exchange intensity. The transient heat exchange intensity serves as the basis for correcting the needle valve displacement of the electronic expansion valve. The corrected needle valve displacement is then converted into a frequency conversion duty cycle correction value and output to S203. If the fin surface temperature and the return air temperature are not synchronized, the temperature controller first performs timing alignment and retains the previous effective duty cycle correction value. The output is updated only after the temperature difference data passes the synchronization verification.

[0022] S203: After reading the frequency converter duty cycle correction value and the thermal power adjustment coefficient, the temperature controller calls the rated frequency range of the refrigeration compressor. The rated frequency range of the refrigeration compressor is the calibration boundary that the refrigeration compressor controller allows for frequency changes in the refrigeration compressor, including the entry conditions, exit conditions, and protection boundaries for frequency adjustment. The frequency converter duty cycle correction value is linearly mapped within this range to form the initial frequency upper limit, which carries the refrigeration compressor operating capacity boundary after the heat exchange correction by the electronic expansion valve. The thermal power adjustment coefficient is then used as a constraint variable in the intersection mapping, so that the initial frequency upper limit is jointly constrained by the endurance redundancy state, the temperature rise trend of the cargo compartment, and the temperature control tolerance of the cargo. The frequency upper limit node under the differentiated redundancy ladder is calibrated by the intersection mapping result, and the frequency upper limit node is the discrete control boundary of the corresponding energy redundancy category and thermal demand category. The temperature controller organizes all effective nodes into a node cluster and performs smooth trajectory fitting on the node cluster to form the refrigeration compressor frequency limit curve. This curve is written into the refrigeration compressor controller's operating constraint area to limit the real-time operating frequency of the refrigeration compressor, and at the same time outputs the frequency boundary that can be called by the pre-cooling strategy to S3. If a sudden node appears in the node cluster, the refrigeration compressor controller fails to confirm the frequency limit command, or the frequency range configuration is abnormal, the temperature controller retains the previous continuous limit curve and outputs a pending confirmation flag.

[0023] S3: Based on the refrigeration compressor frequency limit curve, the temperature controller identifies whether the refrigerated truck is in a parked charging state through the external charging pile protocol handshake signal and reads the current electricity price range. The external charging pile protocol handshake signal is a connection confirmation, safety interlock, and charging permission status signal received by the refrigerated truck's charging communication interface; the parked charging state is the state object where the refrigerated truck's power drive is disengaged and external electrical energy enters the power battery charging link; the electricity price trough range is the range category marked as having low electricity acquisition cost in the peak-valley electricity price topology of the local power supply section. After satisfying the parked charging state and trough electricity price category, the temperature controller obtains the original set temperature of the cargo compartment and the critical temperature point for phase change freezing of the goods. The original set temperature of the cargo compartment comes from the cold chain task order or driver setting, and the critical temperature point for phase change freezing of the goods comes from the goods temperature control file. Under the condition of not falling below the safe freezing boundary temperature of the goods, the temperature controller optimizes the original set temperature of the cargo compartment towards the critical temperature point for phase change freezing of the goods to form the target set temperature of the cargo compartment. The safe freezing boundary temperature for goods is formed by superimposing the critical freezing temperature point of the goods' phase change onto a safety margin, which comes from the goods' temperature control file. If the handshake signal fails to pass the protocol level verification, the electricity price topology cannot be parsed, or the frequency limit curve carries a confirmation flag, the temperature controller will not trigger the off-peak electricity cold storage mechanism, and the target set temperature of the cargo compartment will remain at its original setting.

[0024] S301: After reading the frequency limit curve of the refrigeration compressor, the temperature controller identifies the external charging pile protocol handshake signal through the energy replenishment communication interface. The energy replenishment communication interface receives the connection status, permission status, and safety interlock status between the refrigerated truck and the external charging pile, external power supply, or battery swapping device. The handshake signal is only confirmed as a valid energy replenishment signal after passing protocol level verification, communication integrity verification, and status consistency verification. The standard protocol handshake level is the judgment rule used in the refrigerated truck energy replenishment communication specification to confirm the completion of connection and power supply preparation. When this rule is met, the temperature controller establishes the parking energy replenishment state. Subsequently, the peak-valley electricity price topology of the local power supply section is analyzed. The peak-valley electricity price topology is a mapping data object between the electricity price range of the energy replenishment location, the clock tag, and the electricity acquisition cost category, which comes from the refrigerated truck's preset electricity price table or information issued by the energy replenishment platform. The electricity price range to which the current clock belongs and the parking energy replenishment state jointly enter the electricity acquisition cost accounting stage to form the grid energy replenishment status indicator. The grid energy replenishment status indicator is the trigger judgment object formed by the external electricity replenishment status, parking status, and electricity price category. The external power replenishment status covers the operating status of refrigerated trucks replenishing power to the battery through external charging piles, external power sources, or battery swapping devices. If the current clock does not match the electricity price topology time tag, the temperature controller will mark the grid power replenishment status indicator as not triggered and retain the frequency limit curve for regular temperature control.

[0025] S302: After reading the grid replenishment status indicator, when the indicator meets the off-peak electricity storage trigger rule, the temperature controller triggers the condenser to perform a surge in cooling airflow. The off-peak electricity storage trigger rule is composed of the parking replenishment status, off-peak electricity price category, and the effective status of the refrigeration compressor frequency limit curve. It is used to limit the pre-cooling action to only be executed when both the external replenishment conditions and the refrigeration frequency boundary are met. The surge in condenser cooling airflow is executed by the condenser fan controller. The temperature controller simultaneously acquires the condenser inlet and outlet airflow temperature difference, ambient humidity, windward heat dissipation area, and real-time airflow velocity after the surge in cooling airflow. The condenser inlet and outlet airflow temperature difference comes from the temperature detection elements on the condenser inlet and outlet sides, the ambient humidity comes from the vehicle's external environment detection elements, the windward heat dissipation area comes from the condenser structural configuration, and the real-time airflow velocity comes from the cooling fan feedback or the air duct detection elements. The temperature controller acquires the absolute difference in airflow temperature, correlates it with the atmospheric thermophysical parameters corresponding to the ambient humidity, and combines the windward heat dissipation area and real-time airflow velocity to perform flux accumulation and extrapolation, forming the real-time condensation flux. Real-time condensing flux represents the condenser's ability to release heat under the current airflow conditions. The temperature controller then performs performance calibration by comparing the real-time condensing flux with the factory-calibrated heat dissipation capacity, generating a condenser heat dissipation gain coefficient, which is then output to S303. If the condenser fan command is not confirmed or there is an abnormality in the airflow feedback, the temperature controller will not update the heat dissipation gain coefficient and will output a heat dissipation gain unavailable flag.

[0026] S303: After reading the condenser heat dissipation gain coefficient and the grid power replenishment status index, the temperature controller obtains the critical temperature point for phase change freezing of the carried goods. The critical temperature point for phase change freezing of the goods is the boundary data for the goods to enter the freezing risk state from the preservation temperature zone, which comes from the cold chain task order or the goods temperature control file. The safety margin is the control object used to form the antifreeze protection space in the goods temperature control file. The temperature controller obtains the goods freezing safety boundary temperature by associating the critical temperature point for phase change freezing with the safety margin. The original set temperature of the cargo compartment comes from the temperature control setting of the current transportation task. Before entering the submersion optimization stage, it first undergoes goods category verification and antifreeze boundary verification. When the grid power replenishment status index triggers the off-peak electricity cold storage mechanism, the temperature controller determines the submersion span based on the condenser heat dissipation gain coefficient and the basic cooling step size. The basic cooling step size is the pre-cooling adjustment granularity object built into the temperature controller, which limits the magnitude of the set temperature moving towards the freezing critical direction. After the original set temperature of the cargo compartment is lowered, a candidate set temperature is generated. If the candidate set temperature is higher than the cargo's freezing safety boundary temperature, the target set temperature of the cargo compartment is the candidate set temperature. If the candidate set temperature is lower than or equal to the cargo's freezing safety boundary temperature, the target set temperature of the cargo compartment is the cargo's freezing safety boundary temperature. If the original set temperature of the cargo compartment is lower than the cargo's freezing safety boundary temperature, the target set temperature of the cargo compartment is also the cargo's freezing safety boundary temperature. If the cargo file is missing or the freezing critical temperature point cannot be resolved, the temperature controller will not perform a sub-optimization process and will use the original set temperature as the subsequent temperature control input.

[0027] S4: Based on the target set temperature of the cargo compartment, the temperature controller obtains the current temperature of the cargo compartment and combines it with the target set temperature to form a temperature control demand weight. This temperature control demand weight represents the control object that influences the current temperature control deviation of the cargo compartment on the temperature control distribution tendency of regenerative braking energy. It neither directly changes the braking safety control nor covers the refrigerated truck's regenerative braking strategy, but rather enters the effectiveness calibration stage of the regenerative braking energy amplitude. During the refrigerated truck's operation, the temperature controller monitors the ramp rate of the high-voltage DC bus voltage pump and analyzes the pulse width of the regenerative braking energy. The ramp rate of the high-voltage DC bus voltage pump expresses the state of the bus voltage change along the rising direction during the regenerative braking process, and the pulse width of the regenerative braking energy expresses the pulse width range that the inverter can receive regenerative energy. After the temperature control demand weight is written into the regenerative energy effectiveness calibration, the calibrated regenerative energy is converted into the inverter's transient compensation temperature control gain. The inverter's transient compensation temperature control gain is used to generate a short-time cooling compensation command when the regenerative energy can be absorbed by the refrigeration end. If the braking signal, bus pumping status, and inverter power supply status are inconsistent, the temperature controller will set the energy recovery calibration to a pending confirmation state and prohibit the transient compensation gain from directly acting on the frequency converter.

[0028] S401: After reading the target set temperature of the cargo compartment, the temperature controller obtains the current temperature of the cargo compartment. The current temperature of the cargo compartment comes from temperature detectors deployed inside the cargo compartment. After data acquisition time verification, sensor status verification, and task file verification, it enters the temperature control link. The current temperature of the cargo compartment and the target set temperature of the cargo compartment form a temperature control deviation, which expresses the deviation category of the actual state of the cargo compartment from the target set state. The temperature controller generates a temperature control demand weight based on the temperature control deviation. The more the demand weight is biased towards the refrigeration side, the higher the priority of the recovered energy being converted into temperature control compensation. Subsequently, the voltage rise slope of the high-voltage DC bus is monitored, and the power supply strength is determined based on the rising trend of the bus voltage. The power supply strength is the state category of the energy reinjected into the high-voltage DC bus by braking recovery. The temperature controller analyzes the brake pedal travel and defines the recovery pulse boundary based on the brake pedal travel. The recovery pulse boundary limits the timing range of braking recovery entry, maintenance, and exit. Within the recovery pulse width range defined by the recovery pulse boundary, the temperature controller performs equivalent accumulation extrapolation on the inverter power supply charge to form the initial recovered energy amplitude. The initial recovered energy amplitude is used as a candidate energy object, and then the validity is calibrated by the temperature control demand weight to generate the braking recovered energy amplitude and output it to S402. If the brake pedal travel is inconsistent with the refrigerated truck stability control signal, the recovery pulse boundary is marked as invalid, and the temperature control compensation calibration is exited.

[0029] S402: After reading the regenerative braking energy amplitude, the temperature controller establishes a mapping between the DC bus power supply and the refrigeration compressor drive torque gain. This mapping is derived from the inverter drive calibration and the refrigeration compressor motor control calibration, expressing the control relationship formed by the bus recharge energy entering the refrigeration compressor drive side on the torque compensation capability. The temperature controller acquires the motor iron loss and motor copper loss dissipation. Motor iron loss is the dissipation object generated during the operation of the refrigeration compressor motor magnetic circuit, and motor copper loss is the dissipation object formed by the winding current path. Both are determined by the motor controller operating status and motor calibration data. Before the regenerative braking energy amplitude enters the refrigeration mechanical power conversion, the motor iron loss and motor copper loss dissipation need to be stripped. The stripped energy forms the effective shaft power share. The effective shaft power share is the energy object that enters the refrigeration compressor shaft end and can participate in the refrigeration compression process. The temperature controller continues to acquire the upper limit of the bus capacitor voltage suppression, which is the control boundary object to protect the DC bus energy storage element from excessive voltage. The effective shaft power share, the refrigeration compressor drive torque gain mapping, and the upper limit of bus capacitor voltage suppression are all fed into the refrigeration power mapping gain generation stage to form the refrigeration power mapping gain, which is then output to S403. If the bus capacitor protection state is triggered, the refrigeration power mapping gain is converged to the protection category and fed back to the regenerative braking control side.

[0030] S403: After reading the refrigeration power mapping gain, the temperature controller drives the gas-liquid separator to open the high-flow return gas valve port based on the refrigeration power mapping gain. The high-flow return gas valve port is a controlled valve port state set on the return gas channel of the gas-liquid separator, used to adjust the return gas state of the refrigeration compressor during regenerative braking compensation, avoiding control conflicts between regenerative energy compensation and insufficient refrigerant return gas. The temperature controller acquires the return gas superheat and flow step. The return gas superheat comes from the deviation relationship between the return gas temperature and the corresponding saturation state of the evaporation pressure, and the flow step comes from the refrigerant flow change state caused by the change in the opening of the return gas valve port. The return gas superheat represents the refrigeration compressor suction safety boundary, and the flow step represents the refrigerant flow response speed and amplitude category. The two are combined and then enter the inverter carrier frequency feedforward compensation stage. Before the inverter feedback closed loop completes the response, the feedforward compensation adjusts the carrier frequency in advance according to the return gas state and flow change, so that the speed oscillation deviation caused by the sudden change in braking torque is suppressed within the control boundary. The temperature controller generates the transient compensation temperature control gain of the frequency converter based on the feedforward compensation result and transmits it to S5. If the return air valve port position feedback is not confirmed, the frequency converter carrier frequency remains in the steady-state category, and the transient compensation gain is marked as inactive.

[0031] S5: Based on the transient compensation temperature control gain of the frequency converter, the temperature controller activates the fan delay-stay control after the transient compensation action is completed and the braking signal fades. The fan delay-stay control is a cyclic control mechanism that continues to utilize the residual cooling capacity of the evaporator after the braking recovery compensation exits. Its triggering conditions include the end of the transient compensation action, the capture of the braking signal fading edge, the fan controller being able to receive full-load operation commands, and the evaporator heat exchange status not entering the protection category. After the circulating fan in the cargo compartment is locked in full-load operation, the accumulated cooling capacity in the evaporator is carried away from the fin surface by the circulating airflow and diffuses into the deeper space of the cargo compartment. The temperature controller simultaneously analyzes the refrigerant circulation inertia, suction pressure, air mass flow rate, duct geometric impedance, and peak airflow to form the cargo compartment temperature control result. This distribution result expresses the cooling capacity diffusion state, duct flow field state, and temperature equilibrium state within the cargo compartment space, is written into the cargo compartment temperature monitoring cache, and fed back to subsequent temperature rise rate judgment, cooling limit curve update, and fan stay strategy update. If the brake signal fade-out edge is not captured or the fan full-load command is not confirmed, the temperature controller will not enter the delayed dwell control, and the refrigeration compressor and fan will maintain steady-state operation.

[0032] S501: After reading the transient compensation temperature control gain of the frequency converter, the temperature controller captures the braking signal fading edge. The braking signal fading edge is the edge signal that marks the transition of the braking input from the effective recovery state to the non-recovery state, jointly confirmed by the braking controller and the refrigerated truck stability controller. Upon capturing the braking signal fading edge, the temperature controller triggers a delay-stay mechanism. The delay-stay mechanism does not change the braking state of the refrigerated truck; it only continues to schedule the internal circulation fan after the braking recovery temperature control compensation action ends, allowing the residual cooling capacity of the evaporator to enter the air circulation in the cargo compartment. The temperature controller retrieves the exponential decay curve data of the transient compensation temperature control gain of the frequency converter after braking stops. The exponential decay curve data is the compensation gain exit process state object recorded by the temperature controller, used to calibrate the refrigerant circulation inertia. The refrigerant circulation inertia represents the refrigerant flow capacity remaining in the evaporator, return gas passage, and gas-liquid separator after the compensation action ends. The temperature controller reconciles the refrigerant circulation inertia with the initial state of the inverter's transient compensation temperature control gain, and incorporates the environmental heat transfer damping factor for composite processing to generate a residual cooling capacity sustaining time constant. This residual cooling capacity sustaining time constant is output to S502 as the control boundary during the fan's dwell period. If the gain decay curve data is missing, the temperature controller uses the compensation action completion indicator and the braking fade-out edge to form a conservative dwell state, and records the reason for the missing curve data.

[0033] S502: After reading the residual cooling capacity sustainment time constant, the temperature controller locks the cargo compartment recirculating fan at its highest speed during the delay period defined by the residual cooling capacity sustainment time constant. The highest speed setting is the enhanced circulation state allowed by the fan controller, used to compress the low-temperature air around the evaporator fins into the deeper space of the cargo compartment. The temperature controller extracts the scalar value from the suction pressure transmitter, which is the return air side pressure detection signal, originating from the suction pressure transmitter and verified for communication integrity. This scalar value is converted into the saturated evaporation temperature, which serves as the reference for evaporative heat transfer under the corresponding suction pressure state. The temperature controller continues to acquire the air mass flow rate, which comes from feedback from the cargo compartment recirculating fan, duct status verification, and return air duct status identification. The air mass flow rate, air isobaric specific heat, the difference between the return air temperature and the saturated evaporation temperature, and the residual cooling capacity sustainment time constant are all input into the fin heat transfer equivalent extrapolation stage to generate the evaporator heat transfer flux index. The evaporator heat transfer flux index expresses the ability of the residual cold energy on the fin surface to be released into the circulating air, and is output to S503. If the suction pressure signal exceeds the verification boundary, the fan feedback is not confirmed, or the return air temperature is abnormal, the temperature controller stops updating the heat transfer flux index and maintains a safe circulation state.

[0034] S503: After reading the evaporator heat transfer flux index, the temperature controller drives the accumulated cold energy on the fin surface to force convection diffusion into the depth of the cargo compartment, and acquires the duct geometric impedance and maximum airflow. The duct geometric impedance is the airflow resistance object determined by the cross-sectional characteristics of the cargo compartment duct and the bend resistance coefficient, derived from the cargo compartment structural configuration and duct topology data; the maximum airflow is the airflow state output by the internal circulation fan when it is at its maximum speed, derived from feedback from the fan controller. The temperature controller integrates the duct geometric impedance and maximum airflow to establish a flow field micro-element. The flow field micro-element is a set of spatial grid cells divided in the internal space of the cargo compartment according to the wind direction vector, mass flow rate, and duct topology constraints. Each spatial grid cell carries independent flow velocity characteristics, heat flux determination state, and cold energy diffusion state. The temperature controller writes the evaporator heat transfer flux index into the heat flux determination stage of the flow field micro-element and determines the turbulence intensity and the spatial cold energy penetration depth. Turbulence intensity represents the ability of circulating airflow to create disturbances and diffuse within the spatial grid cells, while spatial cold penetration depth represents the range of cold energy transfer from the evaporator region into the deeper space of the cargo compartment. The temperature controller generates cargo compartment temperature control results based on turbulence intensity and spatial cold penetration depth, and feeds these results back to the cargo compartment temperature monitoring cache. If the duct geometry impedance configuration does not match the current loading state, the flow field micro-element is marked as a category to be verified, and the evaporator heat transfer flux index is retained for circulating fan protection control.

[0035] The temperature control system for the new energy refrigerated truck is used to execute the aforementioned temperature control method for the new energy refrigerated truck. The system includes: The remaining range redundancy analysis module is used to obtain the current state of charge (SOC) and rated capacity of the power battery through the battery management system, and calculate the current available total power based on the current SOC and rated capacity. It also obtains the remaining path length to the target destination, calls the refrigerated truck's mileage energy consumption constant, and uses the current available total power combined with the expected driving energy consumption to perform power boundary delineation and generate a range redundancy value. The refrigeration compressor limit adjustment module is used to read the remaining power redundancy value, compare it with the safety benchmark threshold, extract the temperature rise variation rate of the cargo compartment, calculate the upper limit of the refrigeration compressor inverter frequency, and constrain the operating frequency of the refrigeration compressor using the upper limit of the refrigeration compressor inverter frequency. It is also used to monitor the temperature difference of the evaporator heat exchange fins, drive the electronic expansion valve opening correction, fit the frequency output trajectory, and generate the refrigeration compressor frequency limit curve. The pre-cooling temperature control strategy generation module reads the frequency limit curve of the refrigeration compressor. When the refrigerated truck is identified as being in a parked charging state and the current clock is in a low electricity price range via the external charging pile protocol handshake signal, it obtains the original set temperature of the cargo compartment and the critical temperature point for phase change freezing of the goods. Under the condition that it is not lower than the safe freezing boundary temperature of the goods, it performs a set temperature sinking optimization and generates the target set temperature value of the cargo compartment. The regenerative braking gain mapping module is used to read the target set temperature value of the cargo compartment, obtain the current temperature of the cargo compartment, and generate temperature control demand weights based on the target set temperature value and the current temperature of the cargo compartment. It is also used to monitor the voltage rise slope of the high-voltage DC bus voltage pump during the operation of the refrigerated truck, analyze the pulse width of the regenerative braking pulse, write the temperature control demand weights into the validity calibration of the regenerative braking energy amplitude, and convert the calibrated regenerative energy into the transient compensation temperature control gain of the frequency converter. The cycle intensity feedback adjustment module is used to read the transient compensation temperature control gain of the frequency converter. After the transient compensation action corresponding to the transient compensation temperature control gain of the frequency converter is completed and the braking signal disappears, the fan delay dwell control is activated to force the circulating fan in the cargo compartment to run at full load, driving the cold energy accumulated in the evaporator to diffuse into the deep space of the cargo compartment, generating the cargo compartment temperature control result.

[0036] The above embodiments illustrate preferred embodiments of the present invention. Any equivalent adjustments to the technical solution based on software engineering methods are within the scope of protection, including but not limited to: implementing algorithm logic using different programming languages, refactoring functional modules into services, adjusting data interaction protocols, and optimizing resource scheduling strategies. Any implementation scheme derived from reasonable modifications to the data processing flow, service call chain, or system architecture layer without departing from the core technology of the present invention should be considered within the protection scope defined by the technical solution of the present invention.

Claims

1. A method for temperature control of a new energy refrigerated vehicle, characterized in that, Includes the following steps: S1: Based on the current state of charge and rated capacity of the refrigerated truck's power battery, calculate the current available total power and define the range redundancy value under the current available total power. S2: Determine the upper limit of the inverter frequency of the refrigeration compressor by referring to the battery redundancy value, and constrain the operating frequency of the refrigeration compressor by the upper limit of the inverter frequency of the refrigeration compressor to generate the corresponding refrigeration compressor frequency limit curve; S3: Obtain the original set temperature of the cargo compartment and the critical temperature point of phase change freezing of the goods. Referring to the frequency limit curve of the refrigeration compressor, perform a bottom-up optimization process on the original set temperature of the cargo compartment towards the critical temperature point of phase change freezing of the goods to determine the target set temperature value of the cargo compartment. S4: Obtain the current temperature of the cargo compartment, determine the temperature control demand weight corresponding to the target set temperature value of the cargo compartment and the current temperature of the cargo compartment; during the operation of the refrigerated truck, determine the transient compensation temperature control gain of the frequency converter according to the temperature control demand weight. S5: After the transient compensation action corresponding to the transient compensation temperature control gain of the frequency converter is completed and the braking signal disappears, the fan delay dwell control is activated to force the circulating fan in the cargo compartment to run at full load and generate the cargo compartment temperature control result.

2. The temperature control method of the new energy refrigerated vehicle according to claim 1, characterized in that, The specific steps for obtaining S1 are as follows: S101: Collect the state of charge and rated capacity of the power battery and calculate the current total available power. Combine the bus discharge load to determine the power reference load. Simultaneously obtain the exhaust and suction pressure ratios of the refrigeration compressor. Compare with the standard reference pressure ratio to derive the available power ratio attenuation factor. Perform suppression processing on the power reference load to generate the attenuated power load. Calculate the refrigerant circulation pressure work equivalent using the enthalpy value and refrigerant mass flow rate under suction conditions. Superimpose it with the attenuated power load to obtain the available energy load. S102: Retrieve the remaining navigation path and road segment elevation gradient, convert the rolling resistance parameter and elevation change into work equivalent value, take into account the inverter loss of the drive motor and the mechanical transmission loss, combine the power consumption constant to map the power demand, and generate the predicted power consumption. S103: Read the predicted power consumption and the available energy load, and combine them with the thermal conductivity coefficient of the cargo box enclosure structure, the internal and external temperature difference, the surface area and the expected arrival time to deduce the static heat load of refrigeration and insulation. The redundancy is obtained by subtracting the predicted power consumption and the static heat load from the available energy load, and then calibrating by introducing an energy conversion loss correction coefficient to generate a range redundancy value.

3. The temperature control method of the new energy refrigerated vehicle according to claim 2, characterized in that, The specific steps for obtaining S2 are as follows: S201: Calculate the ratio of the remaining power redundancy value to the preset safety benchmark threshold to obtain the redundancy power adequacy. Calculate the absolute value of temperature deviation based on the real-time temperature of the cargo compartment and the basic set temperature. Combine the redundancy power adequacy, the temperature rise variation rate of the cargo compartment thermistor, the temperature rise tolerance of the goods, and the absolute value of temperature deviation to generate the corresponding thermal power adjustment coefficient. S202: Calculate the fin surface temperature difference based on the air temperature at the evaporator return air inlet and the fin surface temperature, and calculate the transient heat exchange intensity by combining the fin surface temperature difference, surface area heat transfer coefficient and preset feedback correction factor. Correct the electronic expansion valve needle valve displacement according to the transient heat exchange intensity and convert it into the frequency conversion system duty cycle correction value. S203: Combine the duty cycle correction value of the variable frequency system and the rated variable frequency range of the refrigeration compressor to determine the initial upper limit of frequency. Using the thermal power adjustment coefficient as a constraint variable, perform an intersection mapping with the initial upper limit of frequency to construct the frequency limit curve of the refrigeration compressor. Use the frequency limit curve of the refrigeration compressor to limit the real-time operating frequency of the refrigeration compressor.

4. The temperature control method of the new energy refrigerated vehicle according to claim 3, characterized in that, The process of obtaining the transient heat exchange intensity involves multiplying the surface temperature difference of the evaporator fins with the surface area heat transfer coefficient to obtain the initial heat exchange intensity, and then using a feedback correction factor from the control or regulation system of the non-electrical variables to scale the initial heat exchange intensity proportionally to obtain the transient heat exchange intensity.

5. The temperature control method of the new energy refrigerated vehicle according to claim 3, characterized in that, The specific steps for obtaining S3 are as follows: S301: Identify the external charging pile protocol handshake signal through the energy replenishment communication interface, and establish the parking energy replenishment state when the external charging pile protocol handshake signal is identified to meet the standard protocol handshake level. Analyze the peak-valley electricity price topology of the local power supply section, obtain the electricity price range to which the current clock belongs, and determine the grid energy replenishment status index based on the electricity price range to which the current clock belongs and the parking energy replenishment state. The external power replenishment status includes the status in which the refrigerated vehicle replenishes power to the power battery through an external charging pile, external power supply, or battery swapping equipment. S302: When the power grid replenishment status index meets the off-peak electricity storage cold triggering condition, the condenser heat dissipation air volume surge action is triggered. The real-time condensation flux is calculated by integrating the condenser inlet and outlet airflow temperature difference, ambient humidity, windward heat dissipation area and real-time airflow velocity after the surge, and then compared with the factory-calibrated heat dissipation capacity to establish the condenser heat dissipation gain coefficient. S303: When the off-peak electricity storage and cooling mechanism is triggered, the descent span is calculated based on the condenser heat dissipation gain coefficient and the basic cooling step size. The candidate set temperature is obtained by subtracting the descent span from the original set temperature of the cargo compartment. The larger value between the candidate set temperature and the cargo freezing safety boundary temperature is taken as the target set temperature of the cargo compartment. If the original set temperature of the cargo compartment is lower than or equal to the boundary temperature, the cargo freezing safety boundary temperature is taken as the target set temperature value of the cargo compartment.

6. The temperature control method of the new energy refrigerated vehicle according to claim 5, characterized in that, The calculation of real-time condensing flux refers to obtaining the absolute value of the temperature difference between the inlet and outlet airflow of the condenser, correlating the absolute value of the temperature difference between the inlet and outlet airflow of the condenser with the atmospheric thermophysical parameters under the ambient humidity, and performing flux integration calculation by combining the windward heat dissipation area and the real-time airflow velocity after the surge in heat dissipation airflow to obtain the real-time condensing flux.

7. The temperature control method of the new energy refrigerated vehicle according to claim 5, characterized in that, The specific steps for obtaining S4 are as follows: S401: Calculate the temperature control deviation and generate temperature demand weight based on the current temperature of the cargo compartment and the target set temperature, analyze the brake pedal travel to define the recovery pulse boundary, perform equivalent accumulation deduction on the inverter feed charge within this wide range to obtain the initial recovery energy amplitude, and use the temperature demand weight to perform effectiveness calibration on it to generate the braking recovery energy amplitude. S402: The amplitude of the braking energy recovery is separated from the iron loss and copper loss of the motor to establish the effective shaft power share that is converted into refrigeration mechanical work. The effective shaft power share, the DC bus power supply power and the compressor torque gain mapping, and the upper limit of the bus capacitor voltage suppression are integrated to generate the refrigeration power mapping gain. S403: Based on the refrigeration power mapping gain, drive the gas-liquid separator to open the large flow return gas valve port, obtain the return gas superheat and flow step, fuse the return gas superheat and the flow step to perform inverter carrier frequency feedforward compensation, suppress the speed oscillation deviation caused by the sudden change in braking torque of the refrigeration compressor through the inverter carrier frequency feedforward compensation, and generate inverter transient compensation temperature control gain.

8. The temperature control method of the new energy refrigerated vehicle according to claim 7, characterized in that, The specific steps for obtaining S5 are as follows: S501: Capture the fading edge of the braking signal, and trigger the delay dwell mechanism after capturing the fading edge of the braking signal. Based on the exponential decay curve of the transient compensation temperature control gain of the frequency converter, calibrate the inertial stock of the refrigerant circulation flow, and calculate the residual cooling capacity maintenance time constant based on the inertial stock, the initial value of the transient compensation temperature control gain of the frequency converter, and the environmental heat transfer damping factor. S502: During the delayed residence period defined by the residual cold energy maintenance time constant, lock the internal circulation fan of the cargo compartment to the maximum speed, extract the suction pressure and convert it into saturated evaporation temperature, and combine the air mass flow rate, specific heat at constant pressure, the difference between return air and saturated evaporation temperature and the residual cold energy maintenance time constant to deduce and determine the heat exchange flux index of the evaporator. S503: Read the heat transfer flux index of the evaporator, drive the cold energy accumulated on the surface of the fins to be forced to convect and diffuse into the depth of the cargo compartment, integrate the geometric impedance of the air duct and the high-speed air volume to establish a flow field micro-element, use the heat transfer flux index to determine the heat flux, analyze the turbulence intensity and cold energy penetration depth, and generate the cargo compartment temperature control result.

9. The temperature control method of the new energy refrigerated vehicle according to claim 8, characterized in that, The establishment of flow field micro-elements refers to using the cross-sectional characteristics of the cargo compartment air duct and the geometric impedance of the air duct determined by the bend resistance coefficient as topological constraints, and combining the wind direction vector and mass flow rate generated by the internal circulation fan of the cargo compartment at its maximum speed to divide the internal space of the cargo compartment into several spatial grids with independent flow velocities, which serve as flow field micro-elements.

10. Temperature control system for a new energy refrigerated vehicle, characterized in that The system includes: The remaining range redundancy analysis module obtains the current state of charge and rated capacity of the refrigerated truck's power battery, calculates the current available total power, and delineates the range redundancy value under the current available total power. The refrigeration compressor limit adjustment module determines the upper limit of the inverter frequency of the refrigeration compressor by referring to the redundancy value of the remaining power, and constrains the operating frequency of the refrigeration compressor by the upper limit of the inverter frequency of the refrigeration compressor, thereby generating the corresponding refrigeration compressor frequency limit curve. The pre-cooling temperature control strategy generation module obtains the original set temperature of the cargo compartment and the critical temperature point of phase change freezing of the goods. Referring to the frequency limit curve of the refrigeration compressor, it performs a bottom-up optimization process on the original set temperature of the cargo compartment to the critical temperature point of phase change freezing of the goods to determine the target set temperature value of the cargo compartment. The regenerative braking gain mapping module obtains the current temperature of the cargo compartment, determines the temperature control demand weight corresponding to the target set temperature value of the cargo compartment and the current temperature of the cargo compartment, and determines the transient compensation temperature control gain of the frequency converter based on the temperature control demand weight during the operation of the refrigerated truck. The cyclic intensity feedback adjustment module activates the fan delay dwell control after the transient compensation action corresponding to the transient compensation temperature control gain of the frequency converter is completed and the braking signal fades, forcing the circulating fan in the cargo compartment to run at full load and generating the cargo compartment temperature control result.

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