A cooling and heating system and a control method thereof

Abstract

The present invention relates to the technical field of cooling and heating systems, and discloses a control method for a cooling and heating system. When the fan is turned on, the floor heating is also controlled. The floor heating can reduce the temperature of the building, so that the indoor temperature can quickly reach the target value, and can prevent the problems of low humidity and high noise caused by cooling only by the convection wind generated by the fan, so that the room has suitable temperature and humidity and low noise during cooling, and when the cooling is turned off, the indoor temperature can be kept low for a long time, and the comfort level is high. In addition, the present invention determines whether to open the floor valve and whether the floor heating coil is cooled by water according to the target indoor temperature and the target second terminal water supply temperature as well as the detected indoor temperature and indoor dew point temperature, so as to increase the cooling speed, maintain suitable humidity, and avoid condensation. In addition, the present invention also provides a cooling and heating system for realizing the above method.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration and heating systems, and in particular to a refrigeration and heating system and a control method thereof. Background Art

[0002] In areas with hot summers and cold winters, when the air conditioner is turned on, the air convection is driven solely by the fan. Even if the indoor air temperature drops from 35°C to 26°C, the temperature of the wall and roof will exceed 30°C. The hotter the weather, the higher the building temperature, and the stronger the heat exchange capacity of the building's inner surface. The heat exchanger area and temperature of the air conditioner are relatively fixed. In order to eliminate the impact of the building on the air temperature, the air conditioning system must operate with a large air volume, which will be plagued by high noise, strong blowing feeling, dryness, high energy consumption and other problems. In winter, heating with radiators, heaters and other products still has problems such as high air temperature and low wall temperature, energy consumption, noise, dryness and comfort.

[0003] Chinese invention patent CN101832604B (published on June 6, 2012) discloses a central air-conditioning device and its operation control method, the central air-conditioning device includes a main controller for controlling the opening or closing of an air source heat pump main unit, the water outlet of the air source heat pump main unit is connected to the fixed end of a three-way solenoid valve, the normally open end of the three-way solenoid valve is connected to a floor heating and floor cooling return water manifold, the floor heating and floor cooling water outlet manifold is connected to a water pump and then connected to the return water outlet of the air source heat pump main unit; the normally closed end of the three-way solenoid valve is connected to the water inlet of the fan coil unit, the water outlet of the fan coil unit is also connected to the water pump and then connected to the return water outlet of the air source heat pump main unit, the control end of the three-way solenoid valve is connected to a humidity controller, and the humidity controller controls the opening of the normally closed end and the closing of the normally open end of the three-way solenoid valve. In this patent, during summer cooling, the humidity controller can provide ground radiation cooling or fan coil cooling according to the pre-stored set relative humidity. When the ambient relative humidity is lower than the set relative humidity, the ground radiation cooling is used, and when the ambient relative humidity is higher than the set relative humidity, the fan coil cooling is used alone, thereby avoiding the condensation problem of ground radiation cooling in summer. However, this patent relies only on fan cooling, resulting in large fan air volume, high noise, and low and dry indoor humidity. Summary of the invention

[0004] The object of the present invention is to provide a refrigeration and heating system with suitable temperature and humidity, low noise and high comfort and a control method thereof.

[0005] In order to achieve the above-mentioned object, the present invention provides a control method for a cooling and heating system, wherein the cooling and heating system comprises a heat pump unit, a first terminal and a second terminal, wherein the first terminal comprises a fan and a fan coil, and the second terminal comprises a floor heating coil. The heat pump unit is connected with the fan coil and the floor heating coil to form a circulation system, the first terminal is provided with a top valve, and the top valve is used to control whether water enters the fan coil, and the second terminal is provided with a floor valve, and the floor valve is used to control whether water enters the floor heating coil. The control method comprises the following steps:

[0006] A. Detect the current working mode of the heat pump unit. If the current working mode is cooling mode, the fan works and step B is executed;

[0007] Step B includes:

[0008] B1, obtaining the first target temperature Ts1, the target relative humidity Φs and the target second terminal water supply temperature Tg2 as well as the indoor temperature Tn, the indoor relative humidity Φn and the indoor dew point temperature Tl detected in real time;

[0009] B2, high temperature area: when the indoor temperature Tn>35℃, the indoor dew point temperature Tl is not judged and the ground valve is closed;

[0010] B3, transition zone: when the first target temperature Ts1+n℃<indoor temperature Tn≤35℃, n is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl<target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl<target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values;

[0011] B4, first buffer zone: when the first target temperature Ts1+g℃<indoor temperature Tn≤first target temperature Ts1+n℃, g is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl<target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl<target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values;

[0012] B5. Comfort zone: When the first target temperature Ts1-f℃≤indoor temperature Tn≤first target temperature Ts1+g℃, f is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl≤target second terminal water supply temperature Tg2-m℃, the ground valve is open; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl≤target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values;

[0013] B6, second buffer zone: when the first target temperature Ts1-j℃ ≤ indoor temperature Tn ≤ first target temperature Ts1-f℃, j is the set hysteresis value; the indoor dew point temperature Tl is not judged, and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn ﹥ target relative humidity Φs+r, the top valve is opened, and the fan runs at a low speed for dehumidification; when the indoor relative humidity Φn ≤ target relative humidity Φs-r, the top valve is closed, and dehumidification is exited; where r is the set hysteresis value;

[0014] B7. Dehumidification and ventilation area: When the indoor temperature Tn ≤ the first target temperature Ts1-j℃, the indoor dew point temperature Tl is not judged and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn ﹥ the target relative humidity Φs+r, the top valve is opened and the fan runs automatically; if the indoor relative humidity Φn ≤ the target relative humidity Φs-r, the top valve is closed and dehumidification is exited; where r is the set hysteresis value.

[0015] As a preferred solution, in step A, the fan speed is adjusted according to the indoor temperature Tn.

[0016] As a preferred solution, in step A, if the current working mode is the heating mode, step C is executed, and step C includes:

[0017] C1, obtaining the indoor temperature Tn and the second target temperature Ts2 and the detected indoor dew point temperature Tl;

[0018] C2, ventilation area: when the indoor temperature Tn> the second target temperature Ts2+i℃, i is the set hysteresis value; the top valve is closed; no judgment is made on the indoor dew point temperature Tl, and the ground valve is closed;

[0019] C3, Comfort zone: When the second target temperature Ts2-u℃≤indoor temperature Tn≤second target temperature Ts2+i℃, u is the set hysteresis value; no judgment is made on the indoor dew point temperature Tl, and the ground valve adjusts the opening and closing time according to the change of indoor temperature Tn;

[0020] C4, preheating zone: when the indoor temperature Tn ≤ the second target temperature Ts2-u℃, the ground valve opens and the top valve closes.

[0021] As a preferred solution, the value range of n, m, i, g, f, i, and u is 1 to 2, and the value range of j is 3 to 5.

[0022] As a preferred solution, the cooling and heating system includes a humidifier. In steps B4, B5, B6, B7, C2, C1 and C4, if the indoor relative humidity Φn < target relative humidity Φs-40%, the humidifier is turned on, otherwise it is turned off.

[0023] As a preferred solution, the cooling and heating system includes a radiator. In step C3, the radiator is turned on, and when the second target temperature Ts2-u℃﹤indoor temperature Tn≤second target temperature Ts2+i℃, the radiator is turned off with a delay.

[0024] The present invention also provides a cooling and heating system, comprising a heat pump unit, a first end, a second end, an indoor temperature sensor, an indoor dew point temperature acquisition module, an indoor humidity sensor and a central processing unit, wherein the first end comprises a fan and a fan coil, the second end comprises a floor heating coil, and the heat pump unit is connected with the fan coil and the floor heating coil to form a circulation system; the first end is provided with a top valve, and the top valve is used to control whether water enters the fan coil; the second end is provided with a floor valve, and the floor valve is used to control whether water enters the floor heating coil; the heat pump unit, the indoor temperature sensor, the indoor dew point temperature acquisition module, the indoor humidity sensor, the fan, the top valve and the floor valve are communicatively connected with the central processing unit, and the central processing unit controls the heat pump unit, the fan, the top valve and the floor valve according to the detection values ​​of the indoor temperature sensor, the indoor dew point temperature acquisition module and the indoor humidity sensor.

[0025] As a preferred embodiment, it also includes a buffer water tank and a water mixing device, the buffer water tank is provided with a first interface, a second interface, a third interface and a fourth interface, the outlet of the heat pump unit is connected to the inlet of the fan coil, the outlet of the fan coil is connected to the first interface of the buffer water tank, the second interface is connected to the inlet of the floor heating coil through the water mixing device, the outlet of the floor heating coil is connected to the third interface, the fourth interface is connected to the inlet of the heat pump unit, the third interface is connected to a water supply pipeline, the buffer water tank is connected to a water tank exhaust valve, and the water mixing device is communicatively connected to the central controller.

[0026] As a preferred embodiment, the buffer water tank includes a first inner tank and a second inner tank, the first inner tank and the second inner tank are arranged side by side and the middle and bottom are connected, the first interface and the second interface are arranged at the top and bottom of the first inner tank, and the third interface and the fourth interface are arranged at the bottom and top of the second inner tank.

[0027] As a preferred solution, it further comprises a first bypass valve and a second bypass valve, wherein the first bypass valve and the second bypass valve are both connected in parallel with the fan coil unit.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention not only turns on the fan during cooling, but also controls the floor heating. The floor heating can lower the temperature of the building, so that the indoor temperature can quickly reach the target value, and can prevent the problems of low humidity and high noise caused by cooling only by the convective wind generated by the fan, so that the room temperature and humidity are suitable and the noise is small during cooling, and when the cooling is turned off, the indoor low temperature can be maintained for a long time, and the comfort level is high. In addition, the present invention determines whether to open the floor valve and whether the floor heating coil is filled with water for cooling according to the target indoor temperature and the target second terminal water supply temperature as well as the detected indoor temperature and indoor dew point temperature. When the indoor temperature is too high, only the fan is turned on to avoid the problems of heavy load and condensation on the ground caused by the water inflow of the floor heating at this time; when the indoor temperature gradually drops under the operation of the fan, it is determined whether to open the floor valve according to the detected indoor temperature, indoor dew point temperature and target second terminal water supply temperature, so as to increase the cooling speed, maintain suitable humidity and avoid condensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a flow chart of a control method of a cooling and heating system according to a first embodiment of the present invention.

[0031] Figure 2 It is a piping schematic diagram of a cooling and heating system according to a second embodiment of the present invention.

[0032] Figure 3 It is a control schematic diagram of the cooling and heating system of the second embodiment of the present invention.

[0033] Figure 4 It is a schematic structural diagram of a buffer water tank according to the second embodiment of the present invention.

[0034] Figure 5 It is a cross-sectional view of the buffer water tank of the second embodiment of the present invention.

[0035] In the figure, 1-heat pump unit; 2-indoor temperature sensor; 3-indoor dew point temperature acquisition module; 4-indoor humidity sensor; 5-central processing unit; 6-fan; 7-fan coil; 8-floor heating coil; 9-top valve; 10-floor valve; 11-Y-type filter; 12-buffer water tank; 13-water mixing device; 14-first interface; 15-second interface; 16-third interface; 17-fourth interface; 18-water supply pipeline; 19-water tank exhaust valve; 20-switch valve; 21-first Inner tank; 22-second inner tank; 23-drain pipe; 24-connecting pipe; 25-first bypass valve; 26-second bypass valve; 27-expansion tank; 28-safety module switch valve; 29-three-way connecting pipe; 30-one-way valve; 31-variable frequency water pump; 32-mixing water three-way pipe; 33-on-off valve; 34-outer shell; 35-insulation layer; 36-electric heating tube; 37-support; 38-hook; 39-pipeline exhaust valve; 40-humidifier; 41-heating coil; 42-radiator. DETAILED DESCRIPTION

[0036] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0037] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] Embodiment 1

[0040] like Figure 1As shown, a control method for a cooling and heating system of a preferred embodiment of the present invention, the cooling and heating system includes a heat pump unit, a first terminal and a second terminal, the first terminal includes a fan and a fan coil, the second terminal includes a floor heating coil, the heat pump unit is connected with the fan coil and the floor heating coil to form a circulation system, the first terminal is provided with a top valve, the top valve is used to control whether the fan coil is filled with water, the second terminal is provided with a floor valve, the floor valve is used to control whether the floor heating coil is filled with water. The first terminal of this embodiment is a convection terminal, and the second terminal is a radiation terminal. The control method includes the following steps:

[0041] A. Detect the current working mode of the heat pump unit. If the current working mode is cooling mode, the fan works and step B is executed. In this embodiment, the top valve is opened and the fan speed is adjusted according to the indoor temperature Tn.

[0042] Step B includes:

[0043] B1, obtain the first target temperature Ts1, the target relative humidity Φs and the target second terminal water supply temperature Tg2 and the real-time detected indoor temperature Tn, indoor relative humidity Φn, indoor dew point temperature Tl, and control the second terminal; in this embodiment, the first target temperature Ts1 is 26°C, the target relative humidity Φs is 60%, and the target second terminal water supply temperature Tg2 is 18°C;

[0044] B2, high temperature area: when the indoor temperature Tn>35℃, the indoor dew point temperature Tl is not judged, and the ground valve is closed to avoid condensation on the ground and excessive floor load; at the same time, the top valve is opened, the fan is automatically adjusted, and the high-speed operation is carried out to quickly cool and dehumidify;

[0045] B3, transition zone: when the first target temperature Ts1+n℃﹤indoor temperature Tn≤35℃, n is the set hysteresis value, in this embodiment, n is 2, that is, 28℃﹤indoor temperature Tn≤35℃; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl﹤target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point When the temperature Tl is lower than the target second terminal water supply temperature Tg2+i°C, the floor valve is in a standby state; wherein, m and i are set hysteresis values; in this embodiment, m is 2 and i is 1, i.e., when the indoor dew point temperature Tl is lower than 16°C, the floor valve is opened; when the indoor dew point temperature Tl is greater than or equal to 19°C, the floor valve is closed; when the indoor dew point temperature Tl is lower than 19°C, the floor valve is in a standby state; at the same time, the indoor relative humidity Φn is detected, but the indoor relative humidity Φn is not judged, the top valve is opened, and the fan automatically adjusts the speed for cooling and dehumidification;

[0046] B4, first buffer zone: when the first target temperature Ts1+g℃<indoor temperature Tn≤first target temperature Ts1+n℃, g is the set hysteresis value, in this embodiment, g is 1, that is, 27℃<indoor temperature Tn≤28℃; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl<target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃ , the ground valve is closed; when the target second end water supply temperature Tg2-m℃≤indoor dew point temperature Tl<target second end water supply temperature Tg2+i℃, the ground valve is in standby state; wherein, m and i are set hysteresis values; in this embodiment, m is 2 and i is 1, that is, when the indoor dew point temperature Tl<16℃, the ground valve is opened; when the indoor dew point temperature Tl≥19℃, the ground valve is closed; when 16℃≤indoor dew point temperature Tl<19℃, the ground valve is in standby state;

[0047] B5, comfort zone: when the first target temperature Ts1-f℃﹤indoor temperature Tn≤first target temperature Ts1+g℃, f is the set hysteresis value, in this embodiment, f is 2, that is, when 24℃﹤indoor temperature Tn≤27℃; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl﹤target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg 2-m℃≤indoor dew point temperature Tl<target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; wherein, m and i are set hysteresis values; in this embodiment, m is 2 and i is 1, that is, when the indoor dew point temperature Tl<16℃, the ground valve is opened; when the indoor dew point temperature Tl≥19℃, the ground valve is closed; when 16℃≤indoor dew point temperature Tl<19℃, the ground valve is in standby state; at the same time, the top valve is opened, and the fan automatically runs low-speed cooling; this step is usually used for humidity changes in window opening mode;

[0048] B6, second buffer zone: when the first target temperature Ts1-j℃﹤indoor temperature Tn≤first target temperature Ts1-f℃, j is the set hysteresis value, in this embodiment, j is 4, i.e., when 22℃﹤indoor temperature Tn≤24℃; no judgment is made on the indoor dew point temperature Tl, the indoor load is too small, and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn﹥target relative humidity Φs+r, r in this embodiment is 10%, i.e., when the indoor relative humidity Φn﹥70%, the top valve is opened, and the fan runs at a low speed for dehumidification; after the top valve is triggered for dehumidification, when the indoor relative humidity Φn≤target relative humidity Φs-r, i.e., when the indoor relative humidity Φn≤50%, the top valve is closed, and dehumidification is exited;

[0049] B7. Dehumidification and ventilation area: when the indoor temperature Tn≤the first target temperature Ts1-j℃, that is, when the indoor temperature Tn≤22℃, the indoor dew point temperature Tl is not judged, the indoor load is too small, and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn﹥target relative humidity Φs+r, that is, when the indoor relative humidity Φn﹥70%, the top valve is opened, and the fan automatically runs to prevent the room from getting moldy. The system of this embodiment is also provided with a heating coil at the fan. At this time, the heating coil is turned on to prevent the fan from cooling and dehumidifying, causing the indoor temperature to continue to decrease, thereby improving the comfort level; if the indoor relative humidity Φn≤target relative humidity Φs-r, that is, when the indoor relative humidity Φn≤50%, the top valve is closed, dehumidification is exited, and the heating coil is closed.

[0050] In this embodiment, the temperature of the circulating water from the heat pump unit is 7° C. When supplying water to the second end, the target second end water supply temperature Tg2 is reached by mixing water. The target second end water supply temperature Tg2 in this embodiment is 18° C. in the cooling mode. The heat pump unit in this embodiment does not need to adjust its power, that is, it does not need to adjust the temperature of the circulating water output by it. Refrigeration is achieved through the above method, while ensuring appropriate temperature and humidity to improve comfort.

[0051] In this embodiment, the fan is a DC fan, and the fan adopts a stepless speed regulation mode, which can achieve low wind speed, low noise, and low energy consumption, while meeting intermittent rapid cooling and heating. In addition, the fan converts the indoor temperature Tn into an input analog voltage signal for stepless speed regulation of the fan, and the calculation formula of the fan input voltage is V=k1*(Tn-k2)+k3, where V is the DC fan input voltage value; k1 is the voltage change rate; k2 is the temperature value of the minimum wind speed allowed; k3 is the minimum wind speed allowed; k1=0.5, k2=22, k3=2 in this embodiment. Therefore, the calculation formula of the fan input voltage in this embodiment is V=0.5*(Tn-22)+2, where the fan adopts the minimum speed in the dehumidification and ventilation area, the fan adopts the maximum speed in the high temperature area, and the input voltage is obtained by the indoor temperature Tn in the transition area, the first buffer area, the comfort area, and the second buffer area to control the speed. The fan speed regulation table of this embodiment is shown in Table 1.

[0052] Table 1 Fan speed table

[0053]

[0054]

[0055] In step A, if the current working mode is the heating mode, step C is executed, and step C includes:

[0056] C1, obtaining the indoor temperature Tn and the second target temperature Ts2 and the detected indoor dew point temperature Tl;

[0057] C2, ventilation zone: when the indoor temperature Tn> the second target temperature Ts2+i°C, i is the set hysteresis value, the second target temperature Ts2 of this embodiment is 20°C, i is 2, that is, when the indoor temperature Tn> 22°C; the top valve is closed; the indoor dew point temperature Tl is not judged, and the ground valve is closed;

[0058] C3, comfort zone: when the second target temperature Ts2-u℃≤indoor temperature Tn≤second target temperature Ts2+i℃, u is the set hysteresis value, and u in this embodiment is 2, that is, when 18℃≤indoor temperature Tn≤22℃; the indoor dew point temperature Tl is not judged, and the floor valve adjusts the opening and closing time according to the change of indoor temperature Tn;

[0059] C4, preheating zone: when the indoor temperature Tn ≤ the second target temperature Ts2-u℃, that is, when the indoor temperature Tn ≤ 18℃, the ground valve opens; the top valve can be opened or closed to preheat the air using the fan coil.

[0060] In step C2, the opening and closing times of the valve in this embodiment are shown in Table 2.

[0061] Table 2 Opening and closing time of ground valve

[0062]

[0063]

[0064] From the above table, the opening and closing of the valve in step 2 of this embodiment is an intermittent mode. In the heating mode, the temperature of the circulating water from the heat pump unit is 35°C. When supplying water to the second end, the target second end water supply temperature Tg2 is reached by mixing water. The value of the target second end water supply temperature Tg2 in the heating mode of this embodiment is 26°C.

[0065] It should be noted that n, m, i, g, f, i, u, and j are set hysteresis values, which can be set according to needs, and the value range of n, m, i, g, f, i, u is 1 to 2, and the value range of j is 3 to 5.

[0066] In addition, the cooling and heating system of this embodiment includes a humidifier. In steps B4, B5, B6, B7, C2, C1 and C4, if the indoor relative humidity Φn is less than the target relative humidity Φs-40%, the humidifier is turned on, otherwise it is turned off. The cooling and heating system includes a radiator. In step C3, the radiator is turned on, and when the second target temperature Ts2-u℃≤indoor temperature Tn≤second target temperature Ts2+i℃, that is, when 18℃≤indoor temperature Tn≤22℃, the radiator is turned off with a delay. By adding radiators and humidifiers, the comfort level is further improved. The top valve, fan, radiator, heating coil and humidifier of this embodiment can also adopt intermittent mode.

[0067] During cooling, this embodiment not only turns on the fan but also controls the floor heating. The floor heating can lower the temperature of the building so that the indoor temperature can quickly reach the target value, and can prevent the problems of low humidity and high noise caused by cooling only by the convective wind generated by the fan, so that the room temperature and humidity are suitable and the noise is low during cooling, and when the cooling is turned off, the indoor temperature can be kept low for a long time, and the comfort level is high. In addition, this embodiment determines whether to open the floor valve and whether to infuse water into the floor heating coil for cooling based on the target indoor temperature and the target second terminal water supply temperature as well as the detected indoor temperature and indoor dew point temperature. When the indoor temperature is too high, only the fan is turned on to avoid the problems of heavy load and condensation on the ground caused by the inflow of water to the floor heating at this time; when the indoor temperature gradually drops under the operation of the fan, it is determined whether to open the floor valve based on the detected indoor temperature, indoor dew point temperature and target second terminal water supply temperature, which can increase the cooling speed, maintain suitable humidity, and avoid condensation.

[0068] Embodiment 2

[0069] like Figure 2 and Figure 3As shown, this embodiment provides a cooling and heating system, including a heat pump unit 1, a first end, a second end, an indoor temperature sensor 2, an indoor dew point temperature acquisition module 3, an indoor humidity sensor 4 and a central processing unit 5, the first end includes a fan 6 and a fan coil 7, the second end includes a floor heating coil 8, the heat pump unit 1 is connected with the fan coil 7 and the floor heating coil 8 to form a circulation system; the first end is provided with a top valve 9, the top valve 9 is used to control whether water enters the fan coil 7; the second end is provided with a floor valve 10, the floor valve 10 is used to control whether water enters the floor heating coil 8; the heat pump unit 1, the indoor temperature sensor 2, the indoor dew point temperature acquisition module 3, the indoor humidity sensor 4, the fan 6, the top valve 9 and the floor valve 10 are communicated with the central processing unit 5, and the central processing unit 5 controls the heat pump unit 1, the fan 6, the top valve 9 and the floor valve 10 according to the detection values ​​of the indoor temperature sensor 2, the indoor dew point temperature acquisition module 3 and the indoor humidity sensor 4. After receiving the detection values ​​of the indoor temperature sensor 2, the indoor dew point temperature acquisition module 3, and the indoor humidity sensor 4, the central processor 5 of this embodiment is used to perform control according to the method of embodiment 1. The indoor temperature sensor 2 and the indoor humidity sensor 4 are in communication connection with the indoor dew point temperature acquisition module 3, and the indoor dew point temperature acquisition module 3 calculates the dew point temperature according to the temperature information and the humidity information.

[0070] Furthermore, the system of this embodiment further includes a buffer water tank 12 and a water mixing device 13. The buffer water tank 12 is provided with a first interface 14, a second interface 15, a third interface 16 and a fourth interface 17. The outlet of the heat pump unit 1 is connected to the inlet of the fan coil unit 7. The outlet of the fan coil unit 7 is connected to the first interface 14 of the buffer water tank 12. The second interface 15 is connected to the inlet of the floor heating coil 8 through the water mixing device 13. The outlet of the floor heating coil 8 is connected to the third interface 16. The fourth interface 17 is connected to the inlet of the heat pump unit. The third interface 16 is connected to a water supply pipeline 18. The buffer water tank 12 is connected to a water tank exhaust valve 19. The water mixing device 13 is connected to the central controller 5. In this embodiment, during cooling, the circulating water from the heat pump unit 1 first enters the first terminal to achieve rapid convection cooling, and then flows into the buffer water tank 12 for mixing. When the first terminal and the second terminal are opened at the same time, the utilization of heat resources can be improved and condensation on the ground can be avoided. For example, during cooling, the temperature of the circulating water from the heat pump unit 1 is 7°C. After the low-temperature cold water is heat-exchanged in the fan coil 7, it becomes 12°C. After passing through the buffer water tank 12, it is mixed and the temperature is increased. At the same time, after being processed by the water mixing device 13, water above 18°C ​​is provided to the floor heating coil 8 to achieve medium-temperature cooling of the floor and avoid low ground temperature and condensation on the surface. The first interface 14, the second interface 15, the third interface 16 and the fourth interface 17 of this embodiment are all provided with a switch valve 20 for controlling the opening and closing of each interface to achieve single first terminal operation or single second terminal operation or simultaneous operation of the first terminal and the second terminal. A pipeline exhaust valve 39 is provided on the pipeline connecting the heat pump unit 1 and the fan coil 7.

[0071] like Figure 4 As shown, the buffer water tank of this embodiment includes a first inner liner 21 and a second inner liner 22, which are arranged side by side and connected in the middle and the bottom, and the first interface 14 and the second interface 15 are arranged at the top and the bottom of the first inner liner 21, and the third interface 16 and the fourth interface 17 are arranged at the bottom and the top of the second inner liner 22. The buffer water tank 12 has a double-liner structure, which is conducive to the full mixing of cold and hot water, improves the heat exchange efficiency, and can reduce the volume of the buffer water tank 12, which is convenient for indoor installation. In addition, when water enters the first inner tank 21, the pipe diameter becomes larger and the flow rate becomes slower. In the process of entering the second inner tank 22 from the first inner tank 21, the pipe diameter becomes smaller and the flow rate becomes faster. When entering the second inner tank 22, the pipe diameter becomes larger and the flow rate becomes slower. Therefore, according to the principle of the debubbler, the flow rate change of circulating water in the buffer water tank 12 is utilized. After two flow rate changes, this embodiment separates small particles of impurities and bubbles from water upward and downward, which can achieve regular decontamination, rust removal, and bubble removal. The gas is discharged from the water tank exhaust valve 19, and impurities are discharged from the sewage pipeline 23 connected to the third interface 16 to protect the safe operation of the system. The middle and bottom of the first inner tank 21 and the second inner tank 22 are connected by a connecting pipe 24, respectively, which can increase the flow distance of the circulating water in the buffer water tank 12, facilitate the separation of small particle impurities and bubbles, facilitate the effective mixing of the circulating water, and ensure the uniformity of temperature. In addition, an on-off valve 33 is set in the connecting pipe 12 to realize the opening and closing of the connecting pipe 12, forming a two-way buffer tank, which is installed in parallel close to the pipeline, equivalent to adding a large reducer, which has the functions of speed reduction, exhaust and sewage discharge, stores energy, and ensures sufficient water capacity of the system. There is no need to reserve a separate installation position, and it is more practical.

[0072] In addition, the buffer water tank 12 of this embodiment also includes an outer shell 34, and the first inner liner 21 and the second inner liner 22 are both arranged in the outer shell 34. An insulation layer 35 is provided between the first inner liner 21 and the second inner liner 22 and the outer shell 34 to play a protective and heat-insulating role, avoid heat loss, and improve the utilization rate of thermal resources. Furthermore, the inner surfaces of the first inner liner 21 and the second inner liner 22 are provided with an enamel layer, and the inner surfaces are treated with enamel processing to obtain an enamel layer, which can prevent rust, scale and corrosion, and has good durability. In addition, an electric heating tube 36 can be set in the first inner liner 21 and the second inner liner 22. When heating in winter, it can be turned on when the heat pump fails or the low-temperature capacity of the heat pump is attenuated and the heating is insufficient, to play the role of anti-freezing or short-term heating. In this embodiment, the buffer water tank 12 also includes an installation kit, which includes a support 37 and a hanging member 38. The support 37 includes a first plate, a second plate and a third plate. The first plate and the third plate are respectively perpendicular to the two sides of the second plate, and the first plate is located above the second plate, and the third plate is located below the second plate. The hanging member 38 includes a main board and two L-shaped legs vertically connected to both ends of the main board. The L-shaped legs are connected to the shell 34, so that the main board and the shell 34 are at a distance. The third plate is connected to the wall by bolts, and then the shell 34 is placed from top to bottom. The main board of the hanging member 38 falls on the second plate and is located between the first plate and the wall, which is convenient for installation and disassembly, and can realize indoor wall-mounted installation. It is effectively combined with the installation of traditional kitchen cabinets, which is conducive to promotion and implementation. At the same time, sewage discharge and water replenishment can share pipelines with kitchen water and sewage discharge, saving costs, improving installation flexibility, and avoiding the occurrence of cold weather in winter, freezing and bursting of pipes. The water system is less affected by the external environment and runs smoothly as a whole.

[0073] In addition, the system of this embodiment also includes a first bypass valve 25 and a second bypass valve 26, and the first bypass valve 25 and the second bypass valve 26 are connected in parallel with the fan coil 7. The first bypass valve 25 is an electromagnetic two-way valve. When all fan coils 7 are closed or the mode is switched, the first bypass valve 25 is opened to bypass the main circuit and reduce the system resistance; at the same time, it avoids the fan coil 7 and the first bypass valve 25 being under high pressure caused by the water pump for a long time when they are closed, which affects the life of the coil and the electromagnetic valve. In addition, when some fan coils at the first end are opened, when the pressure difference between the supply and return sides of the fan coil 7 is too large, the second bypass valve 26 is opened to balance the water pressure difference between the supply and return sides of the fan coil 7, improve the system utilization, maintain the accurate mutual value of the pressure difference, and minimize the noise of the system. When the terminal load is very small or zero, it can also ensure that a certain amount of water in the cooling and heating system passes through, protect the air-conditioning unit, and also play a role in energy saving and consumption reduction.

[0074] The system of this embodiment also includes a water system safety module, which includes an expansion tank 27, a safety module switch valve 28 and a system exhaust valve. The expansion tank 27 is connected to the first inner tank 21 and the second inner tank 22 through the safety module switch valve 28. The expansion tank 27 is connected with a safety valve and a system exhaust valve, which can adapt to the volume change and pressure change of the circulating water caused by different temperatures. At the same time, the system exhaust valve connected to the expansion tank 27 automatically or manually discharges the bubbles separated in the buffer water tank 12 to ensure the safe and stable operation of the system. Further, the water system safety module also includes a three-way connecting pipe 29, which includes a first branch pipe, a second branch pipe and a third branch pipe connected to each other. The first branch pipe, the second branch pipe and the third branch pipe are respectively connected to the first inner tank 21, the second inner tank 22 and the safety module switch valve 28. A one-way valve 30 is provided on the first branch pipe and the second branch pipe to prevent the first inner tank 21 and the second inner tank 22 from directly passing air and water.

[0075] In this embodiment, the water mixing device 13 includes a proportional integral valve, a variable frequency water pump 31 and a water mixing tee 32. The three ports of the water mixing tee 32 are respectively connected to the second interface 15, the inlet of the variable frequency water pump 31 and the outlet of the floor heating coil 8. The outlet of the variable frequency water pump 31 is connected to the inlet of the floor heating coil 8. The proportional integral valve is arranged at the connection of the water mixing tee 32. The return water flow is adjusted by the opening size of the proportional integral valve, thereby changing the water supply temperature. The stable control of the temperature can avoid the situation that the water temperature is too high during winter heating and causes damage to the floor. On the other hand, it can prevent the floor from condensing due to the low water temperature during summer floor cooling. The variable frequency water pump 31 adopts a constant pressure mode, which can adapt to the flow control of different opening rates at the end, and has good economy. In addition, a Y-type filter 11 is arranged between the second interface 15 and the water mixing tee 32, which can be used to filter and discharge impurities in the first liner 21.

[0076] In addition, the second end also includes a manifold 34, each room is provided with a floor heating coil 8, each floor heating coil 8 is connected to the manifold 34, and the floor valve 10 is integrated with the manifold 34 for distribution and collection. The system of this embodiment also includes a humidifier 40, a heating coil 41 and a radiator 42 that are communicatively connected to the central controller 5. The humidifier 40, the heating coil 41 and the radiator 42 can be turned on or off according to the temperature and humidity of the room, further improving the comfort of the room during cooling or heating. In addition, each room of this embodiment is provided with a room controller, each room controller is respectively communicated with the central processor 5, and the room controller is used to set the target temperature of the room, and each room is provided with an indoor temperature sensor 2, an indoor dew point temperature acquisition module 3, and an indoor humidity sensor 4. The heat pump unit 1, the water mixing device 13 and the room controller are linked together. The heat pump unit 1 and the water mixing device 13 determine the target first-end water supply temperature and the target second-end water supply temperature according to the cooling or heating mode of the room controller. The water pump of the heat pump unit 1 is turned on first with its compressor and three-way valve to facilitate the system water circulation, so that the temperature on the water outlet side is fully mixed and evenly distributed, and the detected value is close to the actual temperature.

[0077] In summary, the embodiment of the present invention provides a control method for a cooling and heating system, which not only turns on the fan but also controls the floor heating during cooling. The floor heating can reduce the temperature of the building, so that the indoor temperature can quickly reach the target value, and can prevent the problem of low humidity and high noise caused by the convective wind cooling generated by the fan alone, so that the room temperature and humidity are suitable and the noise is small during cooling, and when the cooling is turned off, the indoor low temperature can be maintained for a long time, and the comfort level is high. In addition, the present invention determines whether to open the floor valve and whether the floor heating coil is cooled by water according to the target indoor temperature and the target second terminal water supply temperature and the detected indoor temperature and indoor dew point temperature. When the indoor temperature is too high, only the fan is turned on to avoid the problem of heavy load and condensation on the ground caused by the water inflow of the floor heating at this time; when the indoor temperature gradually drops under the operation of the fan, it is determined whether to open the floor valve according to the detected indoor temperature, indoor dew point temperature and target second terminal water supply temperature, which can increase the cooling speed and maintain appropriate humidity and avoid condensation. The embodiment of the present invention also provides a cooling and heating system that can implement the above method, which can quickly cool and heat, avoid condensation on the floor, prevent floor damage, have high heat exchange efficiency, a small water tank volume, and is easy to remove dirt and bubbles.

[0078] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A control method for a cooling and heating system, the cooling and heating system comprising a heat pump unit, a first terminal and a second terminal, the first terminal comprising a fan and a fan coil, the second terminal comprising a floor heating coil, the heat pump unit is connected with the fan coil and the floor heating coil to form a circulation system, the first terminal is provided with a top valve, the top valve is used to control whether the fan coil is filled with water, the second terminal is provided with a floor valve, the floor valve is used to control whether the floor heating coil is filled with water, characterized in that: The steps include: A. Detect the current working mode of the heat pump unit. If the current working mode is cooling mode, the fan works and step B is executed; Step B includes: B1, obtaining the first target temperature Ts1, the target relative humidity Φs and the target second terminal water supply temperature Tg2 as well as the indoor temperature Tn, the indoor relative humidity Φn and the indoor dew point temperature Tl detected in real time; B2, high temperature area: when the indoor temperature Tn>35℃, the indoor dew point temperature Tl is not judged and the ground valve is closed; B3, transition zone: when the first target temperature Ts1+n℃<indoor temperature Tn≤35℃, n is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl<target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl<target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values; B4, first buffer zone: when the first target temperature Ts1+g℃<indoor temperature Tn≤first target temperature Ts1+n℃, g is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl<target second terminal water supply temperature Tg2-m℃, the ground valve is opened; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl<target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values; B5. Comfort zone: When the first target temperature Ts1-f℃≤indoor temperature Tn≤first target temperature Ts1+g℃, f is the set hysteresis value; judge the indoor dew point temperature Tl: when the indoor dew point temperature Tl≤target second terminal water supply temperature Tg2-m℃, the ground valve is open; when the indoor dew point temperature Tl≥target second terminal water supply temperature Tg2+i℃, the ground valve is closed; when the target second terminal water supply temperature Tg2-m℃≤indoor dew point temperature Tl≤target second terminal water supply temperature Tg2+i℃, the ground valve is in standby state; where m and i are the set hysteresis values; B6, second buffer zone: when the first target temperature Ts1-j℃ ≤ indoor temperature Tn ≤ first target temperature Ts1-f℃, j is the set hysteresis value; the indoor dew point temperature Tl is not judged, and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn ﹥ target relative humidity Φs+r, the top valve is opened, and the fan runs at a low speed for dehumidification; when the indoor relative humidity Φn ≤ target relative humidity Φs-r, the top valve is closed, and dehumidification is exited; where r is the set hysteresis value; B7. Dehumidification and ventilation area: When the indoor temperature Tn ≤ the first target temperature Ts1-j℃, the indoor dew point temperature Tl is not judged and the ground valve is closed; and the indoor relative humidity is judged: if the indoor relative humidity Φn ﹥ the target relative humidity Φs+r, the top valve is opened and the fan runs automatically; if the indoor relative humidity Φn ≤ the target relative humidity Φs-r, the top valve is closed and dehumidification is exited; where r is the set hysteresis value.

2. The control method of the cooling and heating system according to claim 1, characterized in that: In step A, the fan speed is adjusted according to the indoor temperature Tn.

3. The control method of the cooling and heating system according to claim 1, characterized in that: In step A, if the current working mode is the heating mode, step C is executed, and step C includes: C1, obtaining the indoor temperature Tn and the second target temperature Ts2 and the detected indoor dew point temperature Tl; C2, ventilation area: when the indoor temperature Tn> the second target temperature Ts2+i℃, i is the set hysteresis value; the top valve is closed; no judgment is made on the indoor dew point temperature Tl, and the ground valve is closed; C3, Comfort zone: When the second target temperature Ts2-u℃≤indoor temperature Tn≤second target temperature Ts2+i℃, u is the set hysteresis value; no judgment is made on the indoor dew point temperature Tl, and the ground valve adjusts the opening and closing time according to the change of indoor temperature Tn; C4, preheating zone: when the indoor temperature Tn ≤ the second target temperature Ts2-u℃, the ground valve opens and the top valve closes.

4. The control method of the cooling and heating system according to claim 3, characterized in that: The value range of n, m, i, g, f, i, and u is 1 to 2, and the value range of j is 3 to 5.

5. The control method of the cooling and heating system according to claim 3, characterized in that: The cooling and heating system includes a humidifier. In steps B4, B5, B6, B7, C2, C1 and C4, if the indoor relative humidity Φn < target relative humidity Φs-40%, the humidifier is turned on, otherwise it is turned off.

6. The control method of the cooling and heating system according to claim 3, characterized in that: The cooling and heating system includes a radiator. In step C3, the radiator is turned on. When the second target temperature Ts2-u°C < indoor temperature Tn ≤ second target temperature Ts2+i°C, the radiator is turned off with a delay.

7. A cooling and heating system, using the control method of the cooling and heating system according to any one of claims 1 to 6, characterized in that: The invention comprises a heat pump unit (1), a first terminal, a second terminal, an indoor temperature sensor (2), an indoor dew point temperature acquisition module (3), an indoor humidity sensor (4) and a central processing unit (5); the first terminal comprises a fan (6) and a fan coil unit (7); the second terminal comprises a floor heating coil unit (8); the heat pump unit (1) is connected to the fan coil unit (7) and the floor heating coil unit (8) to form a circulation system; the first terminal is provided with a top valve (9), the top valve (9) is used to control whether water enters the fan coil unit (7); the second terminal is provided with a floor valve (10), the floor valve (10) is used to control whether water enters the fan coil unit (7); Used to control whether water is entering the floor heating coil (8); the heat pump unit (1), the indoor temperature sensor (2), the indoor dew point temperature acquisition module (3), the indoor humidity sensor (4), the fan (6), the top valve (9) and the floor valve (10) are communicatively connected to the central processing unit (5); the central processing unit (5) controls the heat pump unit (1), the fan (6), the top valve (9) and the floor valve (10) according to the detection values ​​of the indoor temperature sensor (2), the indoor dew point temperature acquisition module (3) and the indoor humidity sensor (4).

8. The cooling and heating system according to claim 7, characterized in that: The heat pump unit (1) further comprises a buffer water tank (12) and a water mixing device (13); the buffer water tank (12) is provided with a first interface (14), a second interface (15), a third interface (16) and a fourth interface (17); the outlet of the heat pump unit (1) is connected to the inlet of the fan coil unit (7); the outlet of the fan coil unit (7) is connected to the first interface (14) of the buffer water tank (12); the second interface (15) is connected to the inlet of the floor heating coil unit (8) through the water mixing device (13); the outlet of the floor heating coil unit (8) is connected to the third interface (16); the fourth interface (17) is connected to the inlet of the heat pump unit (1); the third interface (16) is connected to a water supply pipeline (18); the buffer water tank (12) is connected to a water tank exhaust valve (19); and the water mixing device (13) is communicatively connected to the central controller.

9. The cooling and heating system according to claim 8, characterized in that: The buffer water tank (12) comprises a first inner tank (21) and a second inner tank (22), the first inner tank (21) and the second inner tank (22) being arranged side by side and being connected at the middle and the bottom, the first interface (14) and the second interface (15) being arranged at the top and the bottom of the first inner tank (21), and the third interface (16) and the fourth interface (17) being arranged at the bottom and the top of the second inner tank (22).

10. The cooling and heating system according to claim 8, characterized in that: It also includes a first bypass valve (25) and a second bypass valve (26), wherein the first bypass valve (25) and the second bypass valve (26) are both connected in parallel to the fan coil unit (7).

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