Heat pump dryer detection system and method thereof

Abstract

The invention discloses a heat pump dryer detection system and method, and relates to the technical field of heat pump systems, and the system comprises internal temperature and humidity sensors which are arranged at an evaporator and a compressor; the external temperature and humidity sensor is arranged at the communication position of the heat pump dryer and the drying chamber; the temperature loss model is used for simulating temperature loss of air flowing in the heat pump dryer through a condenser, an evaporator, a fan, an inner temperature and humidity sensor and an outer temperature and humidity sensor and respectively calculating temperature loss generated by the condenser, the evaporator and air flowing; and the scheduling unit is used for determining the adjustment parameters of the condenser, the evaporator and the fan by combining the temperature loss generated by the condenser, the evaporator and air flow through the set temperature and humidity parameters of the control system. The power of the evaporator and the condenser can be adjusted according to the set temperature of the heat pump dryer control system when heat conduction is affected by frosting and dirt of the evaporator and the condenser.

Description

Technical Field

[0001] The invention relates to the technical field of heat pump systems, and in particular to a heat pump dryer detection system and method. Background Art

[0002] When the temperature, humidity and exhaust pressure of the heat pump dryer exceed the safety threshold, it will bring a series of risks and problems to the equipment and operators: Too high temperature: Temperature exceeding the safety threshold may cause the equipment to overheat, affect the drying efficiency, damage the equipment, and high temperature may also cause fire or other safety accidents; Too high humidity: Too high humidity will affect the drying effect. Excessive humidity may also cause frost inside the equipment, affecting the normal operation of the equipment; Exhaust pressure is too high: Excessive exhaust pressure may cause damage to the exhaust system and even cause an explosion risk. Excessive exhaust pressure will also affect the energy efficiency of the equipment.

[0003] Announcement No. CN109282546B discloses a heat pump dryer detection method and system. The heat pump dryer detection method includes an exhaust pressure detection device detecting the exhaust pressure value of the compressor, and an exhaust temperature detection device detecting the exhaust temperature value of the compressor; a judgment device judges whether the exhaust pressure value is greater than or equal to the exhaust pressure safety threshold, and a judgment device judges whether the exhaust temperature value is greater than or equal to the exhaust temperature safety threshold. The control device controls the operating state of the heat pump dryer according to the judgment result of the judgment device. The exhaust pressure detection device and the exhaust temperature detection device work together to detect the exhaust pressure value and exhaust temperature value of the compressor in real time. When any one of the exhaust pressure value or the exhaust temperature value exceeds the set threshold, the control device controls the heat pump dryer to be in a shutdown state. Avoid damage to the equipment caused by the continued operation of the heat pump dryer.

[0004] The heat pump dryer controls the air temperature through the condenser and evaporator, but the condenser and evaporator will have the problem of temperature loss, and there will be a difference between the set temperature of the dryer and the actual temperature entering the drying room.

[0005] The temperature control of heat pump dryer can be roughly divided into two control methods:

[0006] First, according to the set temperature, the condenser and evaporator change parameters such as power to make the air reach the corresponding temperature. However, after the condenser and evaporator are frosted or dirt accumulates, the temperature of the flowing air will be increasingly far from the set temperature, resulting in a large gap between the final temperature entering the drying room and the set temperature.

[0007] Secondly, the discharge temperature of the heat pump dryer is detected. After the condenser and evaporator are frosted and dirt accumulates, they need to reach the set temperature. The condenser and evaporator need to run at a higher power to reach the set discharge temperature. The condenser and evaporator themselves will run at full power, which will accelerate the loss of equipment and reduce its service life.

[0008] Therefore, simply testing the exhaust pressure and temperature cannot determine the temperature loss of the condenser and evaporator. Summary of the invention

[0009] One of the objects of the present invention is to provide a heat pump dryer detection system and method thereof, which determines the temperature loss of a condenser and an evaporator during the operation of the heat pump dryer, and adjusts the condenser and the evaporator according to a set temperature and a change in the temperature loss.

[0010] To achieve the above objectives, the present invention is implemented through the following technical solutions: a heat pump dryer detection system, the heat pump dryer is composed of a condenser for heating air, an evaporator for evaporating refrigerant, a compressor for compressing refrigerant, a fan for air flow, and a control system for controlling the operation of the condenser, the evaporator, the compressor and the fan, and the heat pump dryer is connected to a drying chamber;

[0011] The detection system includes:

[0012] Internal temperature and humidity sensors are installed at the evaporator and compressor to obtain air temperature and humidity data at the evaporator and compressor locations;

[0013] The external temperature and humidity sensor is arranged at the connection position between the heat pump dryer and the drying chamber, and is used to obtain the outlet gas temperature and humidity data of the heat pump dryer;

[0014] Interaction unit, which exchanges data with the control system to obtain the working parameters of the condenser, evaporator and fan;

[0015] The processing unit calculates the standard temperature and humidity data of the corresponding area based on the working parameters of the condenser and the evaporator;

[0016] The temperature loss model simulates the temperature loss of air flowing in the heat pump dryer through the condenser, evaporator, fan, internal temperature and humidity sensors, and external temperature and humidity sensors, and calculates the temperature loss caused by the condenser, evaporator, and air flow respectively;

[0017] The dispatching unit determines the adjustment parameters of the condenser, evaporator and fan by controlling the set temperature and humidity parameters of the system and combining the temperature loss caused by the condenser, evaporator and air flow;

[0018] Based on the working parameters of the condenser, evaporator and fan, the air temperature and humidity changes corresponding to each area are determined. The temperature change temperature loss of the condenser and evaporator is determined in combination with the air temperature and humidity data detected by the internal temperature and humidity sensor. The flow temperature loss is calculated based on the air temperature and humidity data and the gas temperature and humidity data. Based on the temperature and humidity set by the control system, the adjustment parameters of the condenser, evaporator and fan are determined in combination with the temperature change temperature loss and the flow temperature loss.

[0019] In one or more embodiments of the present invention, the air temperature and humidity data and the outlet gas temperature and humidity data generate a temperature curve diagram, which records the operating parameters of the evaporator, condenser and fan corresponding to the temperature and humidity data.

[0020] In one or more embodiments of the present invention, the standard temperature and humidity data corresponding to different powers of the evaporator and condenser are calculated by power, air mass flow rate and specific heat capacity:

[0021] Calculation of evaporator working power corresponding to standard temperature data:

[0022]

[0023] Where, ΔT z is the standard air temperature, Q z is the evaporator power in KW, m is the air mass flow in kg / s, c p is the specific heat capacity of air, in kJ / kg·K;

[0024] Calculation of evaporator working power corresponding to standard humidity data:

[0025]

[0026] Where, ΔW z is the standard humidity of air, h fg is the latent heat of evaporation of water;

[0027] Calculation of condenser working power corresponding to standard temperature data:

[0028]

[0029] Where, ΔT l is the standard air temperature, Q l is the evaporator power in kW.

[0030] In one or more embodiments of the present invention, the temperature and velocity loss caused by the movement of air inside the heat pump dryer is calculated based on the fan operating parameters:

[0031]

[0032] Where ρ is the air density, A is the pipe cross-sectional area, v is the air velocity, ΔP is the pressure loss, and Q is the volume flow rate.

[0033] In one or more embodiments of the present invention, the temperature loss model obtains the air temperature and humidity data detected by the internal temperature and humidity sensor, and calculates the temperature loss between the air temperature and humidity data and the standard temperature and humidity data:

[0034] Evaporator temperature loss:

[0035] ΔT zs =ΔT z -ΔT z1 ;

[0036] Where, ΔT z1 Evaporator temperature data detected by internal temperature and humidity sensors;

[0037] Condenser temperature loss:

[0038] ΔT ls =ΔT l -ΔT l1 ;

[0039] Where, ΔT l1 It is the condenser temperature data detected by internal temperature and humidity sensor.

[0040] In one or more embodiments of the present invention, the control system sets the target drying temperature of the heat pump dryer and calculates the power of the condenser and the evaporator based on the temperature change temperature loss:

[0041] Evaporator power: Q z，adj =Q z +(ΔT zs ·m·c p );

[0042] Condenser power: Q l，adj =Q l +(ΔT ls ·m·c p );

[0043] Evaporator power Q z,adj and condenser power Q l,adj The power required to achieve the target drying temperature.

[0044] In one or more embodiments of the present invention, the air flow temperature loss is calculated by an internal temperature and humidity sensor and an external temperature and humidity sensor:

[0045] ΔT c =ΔT l1 -ΔT2;

[0046] Among them, ΔT2 is the outlet gas temperature data.

[0047] In one or more embodiments of the present invention, the compensation power of the condenser and the dryer is calculated based on the target drying temperature of the control system, and the compensation power is adjusted according to the working parameters of the fan:

[0048] When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency improves, and the overall temperature loss is small;

[0049] When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency increases, and the overall temperature loss is large;

[0050] Determine the corresponding compensation power according to the flow speed of the air affected by the fan;

[0051] The compensation power is combined with the evaporator power and the condenser power to determine the final adjustment parameters.

[0052] The present application also provides a heat pump dryer detection method, which is used in the above heat pump dryer detection system, comprising the following steps:

[0053] The interactive unit acquires the control system to control the power of the condenser, evaporator and fan;

[0054] Obtain air temperature and humidity data detected by the internal temperature and humidity sensor and outlet gas temperature and humidity data detected by the external temperature and humidity sensor;

[0055] Calculate standard temperature and humidity data through condenser and evaporator power;

[0056] Calculate the temperature loss of the condenser and evaporator due to temperature change;

[0057] Calculate the power required to achieve the target drying temperature of the control system based on the temperature change and temperature loss;

[0058] Calculate flow temperature losses;

[0059] Calculate the adjustment parameters of the condenser, evaporator and fan based on the flow temperature losses.

[0060] In one or more embodiments of the present invention, the limit temperature and power of the condenser and evaporator are set, and the maximum duration of the limit temperature and power is determined. The parameters of the condenser and evaporator can be adjusted individually or synchronously.

[0061] Through the above technical solution, the present invention has the following beneficial effects:

[0062] 1. This application calculates the temperature loss of the evaporator and condenser inside the heat pump dryer. When frost and dirt appear on the evaporator and condenser, which affects the heat conduction, the power of the evaporator and condenser can be adjusted according to the set temperature of the heat pump dryer control system, and the temperature loss caused by the fan-driven air flow can be combined to ensure the accuracy of the drying temperature.

[0063] 2. Based on the power of the evaporator and condenser, the ideal temperature that the evaporator and condenser can reach under the corresponding power is calculated, and the temperature and humidity data of the evaporator and condenser are detected by the internal temperature and humidity sensor to determine the temperature loss of the condenser and evaporator, and determine the impact of frost and dirt on the condenser and evaporator.

[0064] 3. Based on the internal temperature and humidity sensor and the external temperature and humidity sensor, the flow temperature loss caused by the air flow is calculated, so that the outlet air temperature of the heat pump dryer can be accurately adjusted to ensure the accuracy of the outlet air temperature and thus ensure a stable drying effect inside the drying room.

[0065] 4. Calculate the adjustment parameters of the condenser, evaporator and fan respectively according to the condenser temperature loss, evaporator temperature loss and air flow temperature loss, and ensure the accuracy of the outlet temperature by changing the power of the evaporator, condenser and fan.

[0066] Other features and advantages of the present invention will be described in the following description, and part of them will become obvious from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 A schematic diagram of the configuration positions of the internal temperature and humidity sensor and the external temperature and humidity sensor of the present invention;

[0068] Figure 2 It is a schematic diagram of the detection system of the present invention;

[0069] In the figure: 100 evaporator, 200 condenser, 300 fan, 400 compressor, 500 drying room, a internal temperature and humidity sensor, b external temperature and humidity sensor. DETAILED DESCRIPTION

[0070] The following will disclose multiple embodiments of the present invention with the accompanying drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. In other words, in some embodiments of the present invention, these practical details are not necessary. And if it is possible to implement, the features of different embodiments can be applied interchangeably.

[0071] Unless otherwise defined, all words (including technical and scientific terms) used herein have their usual meanings, which can be understood by those familiar with this field. Furthermore, the definitions of the above words in commonly used dictionaries should be interpreted as the meanings consistent with the relevant fields of the present invention in the content of this specification. Unless otherwise clearly defined, these words will not be interpreted as idealized or overly formal meanings.

[0072] The present invention provides a heat pump dryer detection system for detecting the heat pump dryer, obtaining the temperature loss of the condenser 200 and the evaporator 100 during the operation of the heat pump dryer, and determining the power parameters of the condenser 200 and the evaporator 100 according to the set temperature and the temperature loss.

[0073] like Figure 1-2 As shown, in one embodiment, the heat pump dryer comprises a condenser 200 for heating air, an evaporator 100 for evaporating refrigerant, a compressor 400 for compressing refrigerant, a fan 300 for air flow, and a control system for controlling the operation of the condenser 200, the evaporator 100, the compressor 400, and the fan 300, and the heat pump dryer is connected to a drying chamber 500;

[0074] The detection system includes:

[0075] Internal temperature and humidity sensor a, which is arranged at the evaporator 100 and the compressor 400, is used to obtain the air temperature and humidity data at the evaporator 100 and the compressor 400;

[0076] The external temperature and humidity sensor b is arranged at the connection position between the heat pump dryer and the drying chamber 500, and is used to obtain the outlet gas temperature and humidity data of the heat pump dryer;

[0077] An interaction unit, which performs data interaction with the control system to obtain the operating parameters of the condenser 200, the evaporator 100 and the fan 300;

[0078] The processing unit calculates the standard temperature and humidity data of the corresponding area based on the working parameters of the condenser 200 and the evaporator 100;

[0079] The temperature loss model simulates the temperature loss of air flowing in the heat pump dryer through the condenser 200, the evaporator 100, the fan 300, the internal temperature and humidity sensor a, and the external temperature and humidity sensor b, and calculates the temperature loss generated by the condenser 200, the evaporator 100, and the air flow respectively;

[0080] The scheduling unit determines the adjustment parameters of the condenser 200, the evaporator 100 and the fan 300 by controlling the set temperature and humidity parameters of the system and combining the temperature loss generated by the condenser 200, the evaporator 100 and the air flow;

[0081] Based on the working parameters of the condenser 200, the evaporator 100 and the fan 300, the air temperature and humidity changes corresponding to each area are determined, and the temperature change temperature loss of the condenser 200 and the evaporator 100 is determined in combination with the air temperature and humidity data detected by the internal temperature and humidity sensor a. The flow temperature loss is calculated based on the air temperature and humidity data and the gas temperature and humidity data. Based on the temperature and humidity set by the control system, the adjustment parameters of the condenser 200, the evaporator 100 and the fan 300 are determined in combination with the temperature change temperature loss and the flow temperature loss.

[0082] In one practicable manner, after the air enters the dryer, three temperature change areas are generated. The first area is located at the evaporator 100. In the evaporator 100, the hot and humid air flows over the surface of the evaporator 100, and the water vapor in the air condenses into water droplets under a low temperature environment and is discharged, while the air is cooled. The second area is located at the condenser 200. The cooled air enters the condenser 200. In the condenser 200, the air is blown by the fan 300, contacts the high-temperature refrigerant, absorbs its heat and heats up. The third area is located between the condenser 200 and the drying chamber 500. Temperature loss occurs during the air flow, causing temperature changes.

[0083] The changes in the three temperature change areas, frost or dirt accumulation on the surface of the evaporator 100 will reduce the heat transfer efficiency and cause temperature loss; the dirt or blockage on the surface of the condenser 200 will reduce the heat transfer efficiency and cause temperature loss; the air movement speed corresponds to the speed of temperature change, therefore, the three temperature change areas are calculated separately to ensure the accurate adjustment of the working parameters of the evaporator 100, condenser 200 and fan 300.

[0084] The temperature loss of the condenser 200 and the evaporator 100 is adjusted according to the temperature loss so that the condenser 200 and the evaporator 100 can reach the set temperature and humidity to ensure the effect of the heat pump dryer. Due to the existence of temperature loss, the condenser 200 and the evaporator 100 will have inconsistent internal and external temperatures. After determining the temperature loss, the internal temperature state of the condenser 200 and the evaporator 100 can be determined to avoid the problem that the internal temperature is too high and exceeds the safety threshold, and the external temperature does not reach the set threshold and still heats up, causing damage to the condenser 200 or the evaporator 100.

[0085] In one embodiment, the air temperature and humidity data and the outlet gas temperature and humidity data generate a temperature curve graph, which records the operating parameters of the evaporator 100, the condenser 200 and the fan 300 corresponding to the temperature and humidity data.

[0086] In one practicable manner, the temperature and humidity data and the operating parameters of the evaporator 100, the condenser 200 and the fan 300 generate a temperature curve, and the temperature changes corresponding to the evaporator 100, the condenser 200 and the fan 300 can be analyzed through the temperature curve, because the power of the evaporator 100 and the condenser 200 affects the overall efficiency of the system. Appropriate power matching can ensure the best heat exchange effect, and too low or too high power will reduce efficiency.

[0087] Increasing the power of the evaporator 100 and the condenser 200 usually increases energy consumption, but if the drying efficiency can be significantly improved, the overall energy consumption may be reduced. Therefore, the temperature curve can be used to analyze the temperature rise state and consider the overall energy consumption state.

[0088] In one embodiment, the standard temperature and humidity data corresponding to different powers of the evaporator 100 and the condenser 200 are calculated by power, air mass flow rate and specific heat capacity:

[0089] Calculation of standard temperature data corresponding to 100 working power of evaporator:

[0090]

[0091] Where, ΔT z is the standard air temperature, Q z is the evaporator 100 power in KW, m is the air mass flow in kg / s, c p is the specific heat capacity of air, in kJ / kg·K;

[0092] Calculation of standard humidity data corresponding to 100 working power of evaporator:

[0093]

[0094] Where, ΔW z is the standard humidity of air, h fg is the latent heat of evaporation of water;

[0095] Calculation of standard temperature data corresponding to the working power of condenser 200:

[0096]

[0097] Where, ΔT l is the standard air temperature, Q l It is the evaporator 100 power in kW.

[0098] In one practicable method, the standard temperature and humidity data are calculated by the power of the condenser 200 and the evaporator 100, without considering the temperature loss caused by frost or dirt on the condenser 200 and the evaporator 100, so as to determine the temperature and humidity state of the air that can be changed under the ideal power state.

[0099] During the actual operation of the condenser 200 and the evaporator 100, frost and dirt cause temperature loss. Therefore, the actual air temperature and humidity data differ from the standard temperature and humidity data. When ensuring that the air temperature and humidity data can reach the set values, the condenser 200 and the evaporator 100 need to output greater power.

[0100] For example, the power of the evaporator 100 is 5 kW, the air mass flow rate is 0.5 kg / s, the specific heat capacity of the air is 1.005 kJ / kg·K, and the latent heat of evaporation is 2257 kJ / kg. The corresponding standard temperature and humidity data of the evaporator 100 are:

[0101]

[0102]

[0103] In one embodiment, the temperature and velocity loss caused by the movement of air inside the heat pump dryer is calculated based on the working parameters of the fan 300:

[0104]

[0105] Where ρ is the air density, A is the pipe cross-sectional area, v is the air velocity, ΔP is the pressure loss, and Q is the volume flow rate.

[0106] In one feasible method, air will encounter resistance when flowing, resulting in pressure drop and temperature change. The greater the resistance, the more significant the temperature loss. The change in air flow velocity caused by the operation of the fan 300 is used to determine the corresponding temperature flow rate loss, and the impact of air temperature changes can be calculated more accurately. It is more accurate when the temperature change and temperature loss of the condenser 200 and the evaporator 100 are calculated through temperature and humidity.

[0107] Exemplarily, the air flow conditions are as follows:

[0108] Air density ρ = 1.2 kg / m 3 ;

[0109] Pipeline cross-sectional area A = 0.1m 2 ;

[0110] Air velocity v = 5 m / s;

[0111] The specific heat capacity of air cp =1005J / kg·K;

[0112] Pipeline length L = 10m;

[0113] Pipe diameter D = 0.1m;

[0114] Friction factor f=0.02.

[0115] Air mass flow:

[0116] m=ρ·A·v=1.2·0.1·5=0.6kg / s;

[0117] Pressure loss:

[0118]

[0119] Power loss:

[0120] P loss =ΔP·Q=ΔP·A·v=0.6·0.5=0.3W;

[0121] Temperature flow rate loss:

[0122]

[0123] In one embodiment, the temperature loss model obtains the air temperature and humidity data detected by the internal temperature and humidity sensor a, and calculates the temperature loss between the air temperature and humidity data and the standard temperature and humidity data:

[0124] Evaporator 100 temperature loss:

[0125] ΔT zs =ΔT z -ΔT z1 ;

[0126] Where, ΔT z1 The temperature data of the evaporator 100 detected by the internal temperature and humidity sensor;

[0127] Condenser 200 temperature loss:

[0128] ΔT ls =ΔT l -ΔT l1 ;

[0129] Where, ΔT l1 The temperature data of the condenser 200 detected by the internal temperature and humidity sensor.

[0130] In one feasible method, the temperature loss of the evaporator 100 and the temperature loss of the condenser 200 are determined, and the temperature difference caused by the frost and dirt accumulation of the evaporator 100 and the condenser 200 under the power of the evaporator 100 and the condenser 200 can be calculated, thereby obtaining the frost and dirt status of the evaporator 100 and the condenser 200.

[0131] In one embodiment, the control system sets the target drying temperature of the heat pump dryer and calculates the power of the condenser 200 and the evaporator 100 based on the temperature change temperature loss:

[0132] Evaporator 100 Power: Q z，adj =Q z +(ΔT zs ·m·c p );

[0133] Condenser 200 Power: Q l，adj =Q l +(ΔT ls ·m·c p );

[0134] Evaporator 100 Power Q z,adj and condenser 200 Q l,adj The power required to achieve the target drying temperature.

[0135] In this embodiment, based on the temperature loss caused by the influence of frost and dirt on the outer walls of the evaporator 100 and the condenser 200 on heat conduction, the power of the evaporator 100 and the condenser 200 is increased to compensate for the problem that the temperature of the condenser 200 and the evaporator 100 cannot reach the target drying temperature due to frost and dirt, thereby ensuring the drying effect of the heat pump dryer during operation and further realizing precise control of the drying temperature of the heat pump dryer.

[0136] When frost and dirt occur, there is a difference between the internal and external temperatures of the evaporator 100 and the condenser 200, and the excessively high temperature inside the condenser 200 may cause damage to the equipment. Therefore, the outlet temperature output is achieved by high-power switching, that is, the evaporator 100 and the condenser 200 perform high-power operation during the switching time period.

[0137] Since the condenser 200 and the evaporator 100 correspond to two areas respectively, and the air flow areas are interconnected, temperature loss will occur during the operation of the fan 300 and the flow of air, resulting in differences in the outlet gas temperature and data of the heat pump dryer. During the operation of the condenser 200 and the evaporator 100, the flow temperature loss caused by the air flow also needs to be considered.

[0138] In one embodiment, the air flow temperature loss is calculated by the internal temperature and humidity sensor a and the external temperature and humidity sensor b:

[0139] ΔT c =ΔT l1 -ΔT2;

[0140] Among them, ΔT2 is the outlet gas temperature data.

[0141] In one feasible method, the temperature loss of air flow from the condenser 200 to the outlet position is calculated to determine the heat loss of the air from the condenser 200 to the drying chamber 500, and the power of the condenser 200 and the evaporator 100 is further adjusted according to the heat loss to ensure that the outlet temperature of the heat pump dryer is consistent with the set temperature.

[0142] The temperature changes of the heat pump dryer during operation are located in three different areas. The areas corresponding to the condenser 200 and the evaporator 100 are affected by the power of the condenser 200 and the evaporator 100. Frost and dirt on the outer surfaces of the condenser 200 and the evaporator 100 will cause heat conduction temperature loss, and air will also produce losses during the flow inside the heat pump dryer. Therefore, the temperature loss of the condenser 200 and the evaporator 100 and the temperature loss during the air flow are detected and calculated, and the power of the condenser 200, the evaporator 100 and the fan 300 are adjusted according to the temperature loss to ensure the accuracy of the temperature.

[0143] In one embodiment, the compensation power of the condenser 200 and the dryer is calculated based on the target drying temperature of the control system, and the compensation power is adjusted according to the working parameters of the fan 300:

[0144] When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency improves, and the overall temperature loss is small;

[0145] When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency increases, and the overall temperature loss is large;

[0146] Determine the corresponding compensation power according to the flow speed of the air affected by the fan 300;

[0147] The compensation power is combined with the power of the evaporator 100 and the power of the condenser 200 to determine the final adjustment parameters.

[0148] In one feasible method, the air flow rate affects the temperature loss. Accordingly, when the condenser 200 and the evaporator 100 cannot be increased too much to ensure the outlet temperature, the air flow rate is adjusted by changing the power of the fan 300 to achieve the stability of the outlet temperature.

[0149] The present application also provides a heat pump dryer detection method, which is used in the above heat pump dryer detection system, comprising the following steps:

[0150] The interactive unit acquires the power of the control system to control the condenser 200, the evaporator 100 and the fan 300;

[0151] Obtain the air temperature and humidity data detected by the internal temperature and humidity sensor a and the outlet gas temperature and humidity data detected by the external temperature and humidity sensor b;

[0152] Calculate standard temperature and humidity data through the power of condenser 200 and evaporator 100;

[0153] Calculate the temperature loss of the condenser 200 and the evaporator 100 due to temperature change;

[0154] Calculate the power required to achieve the target drying temperature of the control system based on the temperature change and temperature loss;

[0155] Calculate flow temperature losses;

[0156] Adjustment parameters of the condenser 200 , the evaporator 100 , and the fan 300 are calculated based on the flow temperature loss.

[0157] In one embodiment, the limit temperature and power of the condenser 200 and the evaporator 100 are set, and the maximum duration of the limit temperature and power is determined. The parameters of the condenser 200 and the evaporator 100 can be adjusted individually or synchronously.

[0158] In summary, the technical solutions disclosed in the above embodiments of the present invention have at least the following advantages:

[0159] 1. This application calculates the temperature loss of the evaporator and condenser inside the heat pump dryer. When frost and dirt appear on the evaporator and condenser, which affects the heat conduction, the power of the evaporator and condenser can be adjusted according to the set temperature of the heat pump dryer control system, and the temperature loss caused by the fan-driven air flow can be combined to ensure the accuracy of the drying temperature.

[0160] 2. Based on the power of the evaporator and condenser, the ideal temperature that the evaporator and condenser can reach under the corresponding power is calculated, and the temperature and humidity data of the evaporator and condenser are detected by the internal temperature and humidity sensor to determine the temperature loss of the condenser and evaporator, and determine the impact of frost and dirt on the condenser and evaporator.

[0161] 3. Based on the internal temperature and humidity sensor and the external temperature and humidity sensor, the flow temperature loss caused by the air flow is calculated, so that the outlet air temperature of the heat pump dryer can be accurately adjusted to ensure the accuracy of the outlet air temperature and thus ensure a stable drying effect inside the drying room.

[0162] 4. Calculate the adjustment parameters of the condenser, evaporator and fan respectively according to the condenser temperature loss, evaporator temperature loss and air flow temperature loss, and ensure the accuracy of the outlet temperature by changing the power of the evaporator, condenser and fan.

[0163] Although the present invention is disclosed in conjunction with the above embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the attached claims.

Claims

1. A heat pump dryer detection system, the heat pump dryer consists of a condenser for heating air, an evaporator for evaporating refrigerant, a compressor for compressing refrigerant, a fan for air flow, and a control system for controlling the operation of the condenser, evaporator, compressor and fan, and the heat pump dryer is connected to a drying room; characterized in that, The detection system includes: Internal temperature and humidity sensors are installed at the evaporator and compressor to obtain air temperature and humidity data at the evaporator and compressor locations; The external temperature and humidity sensor is arranged at the connection position between the heat pump dryer and the drying chamber, and is used to obtain the outlet gas temperature and humidity data of the heat pump dryer; Interaction unit, which exchanges data with the control system to obtain the working parameters of the condenser, evaporator and fan; The processing unit calculates the standard temperature and humidity data of the corresponding area based on the working parameters of the condenser and the evaporator; The temperature loss model simulates the temperature loss of air flowing in the heat pump dryer through the condenser, evaporator, fan, internal temperature and humidity sensors, and external temperature and humidity sensors, and calculates the temperature loss caused by the condenser, evaporator, and air flow respectively; The dispatching unit determines the adjustment parameters of the condenser, evaporator and fan by controlling the set temperature and humidity parameters of the system and combining the temperature loss caused by the condenser, evaporator and air flow.

2. A heat pump dryer detection system according to claim 1, characterized in that: The air temperature and humidity data and the outlet gas temperature and humidity data generate a temperature curve diagram, and the temperature curve diagram records the working parameters of the evaporator, condenser and fan corresponding to the temperature and humidity data.

3. A heat pump dryer detection system according to claim 2, characterized in that: The standard temperature and humidity data corresponding to different powers of evaporator and condenser are calculated by power, air mass flow and specific heat capacity: Calculation of evaporator working power corresponding to standard temperature data: Where, ΔT z is the standard air temperature, Q z is the evaporator power in KW, m is the air mass flow in kg / s, c p is the specific heat capacity of air, in kJ / kg·K; Calculation of evaporator working power corresponding to standard humidity data: Where, ΔW z is the standard humidity of air, h fg is the latent heat of evaporation of water; Calculation of condenser working power corresponding to standard temperature data: Among them, ΔT1 is the standard air temperature, Q1 is the evaporator power in kW.

4. A heat pump dryer detection system according to claim 3, characterized in that: Calculate the temperature and velocity loss caused by the movement of air inside the heat pump dryer based on the fan operating parameters: Where p is the air density, A is the pipe cross-sectional area, v is the air velocity, ΔP is the pressure loss, and Q is the volume flow rate.

5. A heat pump dryer detection system according to claim 4, characterized in that: The temperature loss model obtains the air temperature and humidity data detected by the internal temperature and humidity sensor, and calculates the temperature loss between the air temperature and humidity data and the standard temperature and humidity data: Evaporator temperature loss: ΔT zs =ΔT z -ΔT z1 ; Where, ΔT z1 Evaporator temperature data detected by internal temperature and humidity sensors; Condenser temperature loss: ΔT ls =ΔT l -ΔT l1 ; Where, ΔT l1 It is the condenser temperature data detected by internal temperature and humidity sensor.

6. A heat pump dryer detection system according to claim 5, characterized in that: The control system sets the target drying temperature of the heat pump dryer and calculates the power of the condenser and evaporator based on the temperature change loss: Evaporator power: Q z，adj =Q z +(ΔT zs ·m·c p ); Condenser power: Q l，adj =Q l +(ΔT ls ·m·c p ); Evaporator power Q z，adj and condenser power Q l，adj The power required to achieve the target drying temperature.

7. A heat pump dryer detection system according to claim 6, characterized in that: Calculate the air flow temperature loss through the internal temperature and humidity sensor and the external temperature and humidity sensor: ΔT c =ΔT l1 -ΔT2; Among them, ΔT2 is the outlet gas temperature data.

8. A heat pump dryer detection system according to claim 7, characterized in that: The compensation power of the condenser and dryer is calculated based on the target drying temperature of the control system, and the compensation power is adjusted according to the working parameters of the fan: When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency improves, and the overall temperature loss is small; When the air velocity is fast, the air mass flow rate increases, the power loss increases, the heat exchange efficiency increases, and the overall temperature loss is large; Determine the corresponding compensation power according to the flow speed of the air affected by the fan; The compensation power is combined with the evaporator power and the condenser power to determine the final adjustment parameters.

9. A heat pump dryer detection method, used in the heat pump dryer detection system according to any one of claims 1 to 8, characterized in that: The following steps are involved: The interactive unit acquires the control system to control the power of the condenser, evaporator and fan; Obtain air temperature and humidity data detected by the internal temperature and humidity sensor and outlet gas temperature and humidity data detected by the external temperature and humidity sensor; Calculate standard temperature and humidity data through condenser and evaporator power; Calculate the temperature loss of the condenser and evaporator due to temperature change; Calculate the power required to achieve the target drying temperature of the control system based on the temperature change and temperature loss; Calculate flow temperature losses; Calculate the adjustment parameters of the condenser, evaporator and fan based on the flow temperature losses.

10. A heat pump dryer detection method according to claim 9, characterized in that: Set the limit temperature and power of the condenser and evaporator, and determine the maximum duration of the limit temperature and power. The parameters of the condenser and evaporator can be adjusted separately or synchronously.

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