Control method of heat recovery system, heat recovery system, air conditioner and storage medium

Abstract

The invention relates to a control method of a heat recovery system, the heat recovery system, an air conditioner and a storage medium, and relates to the technical field of heat recovery. The control method comprises the following steps that the heating requirement of a heating loop and the refrigerating requirement of a refrigerating loop are obtained; when the heating requirement is smaller than the refrigerating requirement, the heating water return section communicates with the dynamic water tank, and at least part of liquid in the heating water return section is equivalently replaced with liquid in the dynamic water tank, so that the temperature of the liquid at the tail end of the heating water return section is reduced; and when the refrigeration requirement is smaller than the heating requirement, the refrigeration water return section communicates with the dynamic water tank, and at least part of liquid in the refrigeration water return section is equivalently replaced with liquid in the dynamic water tank, so that the temperature of the liquid at the tail end of the refrigeration water return section is increased. The temperature of the heating loop and the temperature of the refrigerating loop can be adjusted through the dynamic water tank, so that the condensation side and the evaporation side of the heat recovery unit are balanced, and hot water supplied by the heating loop and cold water supplied by the refrigerating loop both meet the use requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of heat recovery, and in particular to a control method of a heat recovery system, a heat recovery system, an air conditioner and a storage medium. Background Art

[0002] The heat recovery unit has a condenser and an evaporator. When in use, the heat exchange medium in the condenser can be condensed and dissipated to heat the external water channel to achieve the effect of heating. The condensed heat exchange medium passes through the evaporator and evaporates to absorb heat from the external water channel to achieve the effect of cooling. It can achieve the effects of cooling and heating at the same time.

[0003] In order to ensure the normal operation of the heat recovery unit, it is necessary to ensure that the heat exchange medium absorbs heat in the condenser in time and dissipates heat in the evaporator in time. However, during use, the cooling demand and heating demand of the user are often different. For example, when the cooling demand is greater than the heating demand, in order to ensure that the cooling power on the evaporator side meets the requirements, it is necessary to use the cooling tower to cool down the condenser side in time to ensure that the condensation speed of the heat exchange medium in the condenser corresponds to the evaporation speed on the evaporator side.

[0004] That is to say, when the cooling demand is unbalanced with the heating demand, it is often necessary to start heat exchange equipment such as cooling towers to adjust the heat exchange load on both sides of the heat recovery unit, and the energy consumption of the heat recovery system is relatively large. Summary of the invention

[0005] The present invention provides a control method for a heat recovery system, a heat return water system, an air conditioner and a storage medium, which are used to reduce the energy consumption of the heat recovery system when the cooling demand and the heating demand are unbalanced.

[0006] The present invention provides a control method for a heat recovery system, the control method comprising the following steps:

[0007] Obtain heating demand of the heating circuit and cooling demand of the cooling circuit;

[0008] When the heating demand is less than the cooling demand, the heating return water section is connected to the dynamic water tank, so that at least part of the liquid in the heating return water section is replaced by the liquid in the dynamic water tank, so as to reduce the liquid temperature at the end of the heating return water section;

[0009] When the cooling demand is less than the heating demand, the refrigeration return water section is connected to the dynamic water tank so that at least part of the liquid in the refrigeration return water section is replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the refrigeration return water section. The dynamic water tank corresponding to the heating return water section and the dynamic water tank corresponding to the refrigeration return water section are the same dynamic water tank.

[0010] In one embodiment, when the heating water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0011] Obtain the cooling demand of the heating return water section and the maximum cooling capacity of the dynamic water tank;

[0012] Determine whether the maximum cooling capacity of the dynamic water tank meets the cooling demand of the heating return water section;

[0013] If the maximum cooling capacity of the dynamic water tank cannot meet the cooling demand of the heating return water section, the cooling tower is controlled to cool the liquid in the dynamic water tank.

[0014] In one embodiment, the cooling demand of the heating return water section is calculated according to the following formula:

[0015] P 1冷 -P 2热 =P 2冷

[0016] Among them, P 1冷 is the cooling demand of the refrigeration circuit, P 2热 is the heating demand of the heating circuit, P 2冷 It is the cooling demand of the heating return water section.

[0017] In one embodiment, the maximum cooling capacity of the dynamic water tank is calculated according to the following formula:

[0018] P 回冷 =Cp*r*Vs thermal recovery*ΔT1

[0019] Among them, P is the maximum cooling capacity of the dynamic water tank, Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT1=T 热回 -T 动 , t 热回 is the temperature of the liquid at the inlet of the heating return water section, T 动 is the temperature of the liquid in the dynamic water tank.

[0020] In one embodiment, when the refrigeration return water section is connected to the dynamic water tank, the control method further includes the following steps:

[0021] Obtain the heating demand of the refrigeration return water section and the maximum heating capacity of the dynamic water tank;

[0022] Determine whether the maximum heating capacity of the dynamic water tank meets the heating requirements of the refrigeration return water section;

[0023] When the maximum heating capacity of the dynamic water tank cannot meet the heating demand of the refrigeration return water section, the cooling tower is controlled to heat the liquid in the dynamic water tank.

[0024] In one embodiment, the heating demand of the heating circuit is calculated according to the following formula:

[0025] P 2热 =Cp*r*Vs thermal return*ΔT2;

[0026] Where Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT2=T 供热 -T 热回 , T 热回 is the temperature of the liquid at the inlet of the heating return water section, T 供热 The liquid heating temperature is set for the heating return section. The liquid in the dynamic water tank is the same as the liquid in the heating circuit.

[0027] In one embodiment, when the heating water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0028] Obtaining the liquid temperature of the heating circuit at the heating water supply section;

[0029] When the liquid temperature of the heating water supply section is lower than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to decrease;

[0030] When the liquid temperature of the heating water supply section is higher than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to increase.

[0031] In one embodiment, the control method further comprises:

[0032] Determine whether the difference between the heating demand and the cooling demand is greater than the fluctuation threshold;

[0033] When the difference between the heating demand and the cooling demand is less than the fluctuation threshold, the heating return water section and the cooling return water section are controlled to be disconnected from the dynamic water tank respectively.

[0034] In one embodiment, the control method further comprises the following steps:

[0035] When the heating circuit has no heating demand and the refrigeration circuit has refrigeration demand, the cooling tower is controlled to be connected to the condensation side to dissipate heat from the condensation side;

[0036] When the heating circuit has a heating demand and the refrigeration circuit has no refrigeration demand, the cooling tower is controlled to be connected to the evaporation side to increase the temperature of the evaporation side.

[0037] In a second aspect, the present invention further provides a heat recovery system, which comprises:

[0038] A heat recovery unit having a condensing side and an evaporating side;

[0039] A heating circuit, which is connected to the condensation side;

[0040] a refrigeration circuit, which is in communication with the evaporation side;

[0041] A dynamic water tank, the heating water return section of the heating circuit and the cooling water return section of the cooling circuit are selectively connected to the dynamic water tank respectively; and

[0042] A controller, the controller being electrically connected to the dynamic water tank, and when the heating demand of the heating water return section is less than the cooling demand of the cooling water return section, the controller controls the dynamic water tank to be connected to the heating water return section, so that at least part of the liquid in the heating water return section is replaced by the liquid in the dynamic water tank in equal amount, so as to reduce the temperature of the liquid at the end of the heating water return section;

[0043] When the heating demand of the heating return water section is greater than the cooling demand of the cooling return water section, the controller controls the dynamic water tank to be connected with the cooling return water section, so that the liquid in the cooling return water section is at least partially replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the cooling return water section.

[0044] In one embodiment, the heat recovery system further comprises a cooling tower, and the cooling tower is electrically connected to the controller;

[0045] When the heating circuit has no heating demand and the refrigeration circuit has refrigeration demand, the cooling tower is controlled to be connected to the condensation side to dissipate heat from the condensation side;

[0046] When the heating circuit has a heating demand and the refrigeration circuit has no refrigeration demand, the cooling tower is controlled to be connected to the evaporation side to increase the temperature of the evaporation side.

[0047] In a third aspect, the present invention further provides an air conditioner, which includes the above-mentioned heat recovery system.

[0048] In a fourth aspect, the present invention further provides a storage medium having a computer program stored thereon, wherein the computer program implements the above-mentioned control method when executed by a processor.

[0049] Compared with the prior art, the advantage of the present invention is that when the cooling demand of the refrigeration circuit is higher than the heating demand of the heating circuit, the liquid in the heating return water section can be cooled by replacing part of the liquid in the heating return water section with the liquid in the dynamic water tank, thereby taking away more heat on the condensing side, so that the cooling and heating demands of the heat recovery unit are balanced and the performance of the heat recovery unit is guaranteed. Since part of the liquid in the heating return water section is replaced with the dynamic water tank, the temperature of the liquid in the dynamic water tank can be gradually increased to achieve heat storage. When the heat recovery system changes to a cooling demand lower than the heating demand, the liquid in the dynamic water tank after the temperature is increased can be replaced with the liquid in the refrigeration return water section, thereby heating the evaporation side and avoiding the heat recovery unit from malfunctioning due to the excessively low temperature on the evaporation side. Moreover, the temperature of the liquid in the dynamic water tank can be lowered by the refrigeration circuit, and the temperature of the liquid in the dynamic water tank can be increased by the heating circuit, so that the temperature of the liquid in the dynamic water tank is maintained between the water temperature of the heating return water section and the temperature of the cooling return water section. Compared with a water tank connected to a single heat exchange circuit, this avoids the liquid in the water tank from constantly rising or falling in temperature, thereby greatly improving the temperature regulation ability of the dynamic water tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Hereinafter, the present invention will be described in more detail based on embodiments and with reference to the accompanying drawings.

[0051] Figure 1 is a structural block diagram of a heat recovery system in an embodiment of the present invention;

[0052] Figure 2 is a flow chart of a control method of a heat recovery system in an embodiment of the present invention;

[0053] Figure 3 is another flow chart of a control method of a heat recovery system in an embodiment of the present invention;

[0054] Figure 4 is another flow chart of a control method of a heat recovery system in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The present invention will be further described below in conjunction with the accompanying drawings.

[0056] Since the working principle of the heat recovery unit is to achieve heating and cooling through the evaporation and condensation cycle of the internal heat exchange medium. When the heat recovery unit is working, the heat generated on the condenser side and the heat absorbed on the evaporator side.

[0057] Ideally, the user's cooling demand and heating demand are equal, and the heat exchange balance of the heat recovery unit can be guaranteed without external adjustment, so that the temperature at the condenser and the temperature at the evaporator are both in the appropriate temperature range.

[0058] However, in actual use, the cooling demand and heating demand of the user are often not equal. For example, in hot weather, the outside temperature is high, and the heat recovery unit is required to increase the cooling capacity. Obviously, the cooling demand of the heat recovery unit is much greater than the heating demand. If the heat exchange power of the heat recovery unit is set according to the cooling needs, the actual heating capacity of the heat recovery unit on the condenser side will be greater than the heating demand, which may cause the liquid temperature in the hot water supply section of the heating circuit to be higher than the user's needs, not meeting the user's requirements, and the liquid temperature flowing into the condenser side of the heating return section will also rise, further affecting the operation of the heat recovery unit. At this time, additional cooling equipment such as a cooling tower needs to be started to cool the hot water supply section of the heating circuit, increasing the energy consumption of the heat recovery system.

[0059] Similar problems will also occur when the heating demand is greater than the cooling demand. That is, because the cooling capacity of the refrigeration circuit is lower than the cooling capacity of the evaporator, the temperature of the refrigeration water supply section will be too low, affecting the actual experience of the user. And it will cause the temperature of the refrigeration return water section connected to one side of the evaporator to be too low, reducing the evaporation efficiency of the heat exchange medium in the evaporator, which in turn reduces the heating power of the heating circuit. In the related technology, when the heat recovery unit is started, the cooling tower will be additionally started to heat the evaporator, which increases the energy consumption of the heat recovery system.

[0060] In a first aspect, the present invention provides a control method for a heat recovery system, wherein the heat recovery system comprises: the heat recovery system comprises a heat recovery unit, the condensing side of the heat recovery unit is connected to a heating circuit, the evaporating side of the heat recovery unit is connected to a refrigeration circuit, the heat recovery system also comprises a dynamic water tank, the heating return water section of the hot water circuit and the refrigeration return water section of the refrigeration circuit are selectively connected to the dynamic water tank respectively.

[0061] In other words, the heating circuit can be heated through the condensing side of the heat recovery unit, so that the water supply section of the heating circuit provides heat to the external heat-consuming equipment. After the liquid in the refrigeration circuit passes through each heat-consuming equipment, it can flow back from the heating return water section. At the same time, the refrigeration circuit can be cooled through the evaporation side of the heat recovery unit, so that the water supply section of the refrigeration circuit provides cooling to the external cold-consuming equipment. After the liquid in the refrigeration circuit passes through each cold-consuming equipment, it can flow back from the refrigeration return water section.

[0062] The control method of the heat recovery system comprises the following steps:

[0063] Obtain heating demand of the heating circuit and cooling demand of the cooling circuit;

[0064] When the heating demand is less than the cooling demand, the heating return water section is connected to the dynamic water tank, so that at least part of the liquid in the heating return water section is replaced by the liquid in the dynamic water tank, so as to reduce the liquid temperature at the end of the heating return water section;

[0065] When the cooling demand is less than the heating demand, the refrigeration return water section is connected to the dynamic water tank so that at least part of the liquid in the refrigeration return water section is replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the refrigeration return water section. The dynamic water tank corresponding to the heating return water section and the dynamic water tank corresponding to the refrigeration return water section are the same dynamic water tank.

[0066] It should be noted that the liquid temperature of the heating return water section is generally higher than the room temperature, while the liquid temperature of the cooling return water section is generally lower than the room temperature. In other words, the liquid temperature of the heating return water section is generally higher than the liquid temperature of the cooling return water section. After the heating circuit is connected to the dynamic water tank, the water in the dynamic water tank will be mixed with the water in the heating circuit, so that the water temperature in the dynamic water tank will be gradually adjusted to a temperature close to that at the heating return water section. Similarly, after the cooling return water section is connected to the dynamic water tank, the water temperature in the dynamic water tank will gradually approach the water temperature at the cooling return water section. After long-term use, the liquid temperature in the dynamic water tank will be between the water temperature of the cooling return water section and the water temperature of the heating return water section.

[0067] When the heating demand is less than the cooling demand, the heating return water section is connected to the dynamic water tank, and the liquid in the cooling return water section is replaced by the liquid in the dynamic water tank. The liquid temperature in the dynamic water tank is lower than the water temperature at the entrance of the heating return water section, which will cause the liquid temperature in the heating return water section to drop, better take away the temperature of the heat recovery unit on the condensing side, and avoid the water temperature in the heating water supply section from rising when the power of the heat recovery unit remains unchanged, supply heat to the heat-consuming equipment on demand, and avoid supplying too much heat to the heat-consuming equipment to affect the use effect. On the other hand, the temperature of the liquid in the dynamic water tank will rise synchronously, achieving the effect of heat storage.

[0068] The dynamic water tank can be closed and a heat recovery circulation pump can be set at the heating return water section. The liquid in the dynamic water tank can be pumped out by the heat recovery circulation pump to complete the replacement of the liquid in the dynamic water tank with the liquid in the heating return water section.

[0069] When the cooling demand is less than the heating demand, the cooling water return section is connected to the dynamic water tank so that at least part of the liquid in the cooling water return section is replaced by the liquid in the dynamic water tank. The temperature of the liquid in the dynamic water tank is higher than the water temperature of the cooling water return section. Passing the liquid in the dynamic water tank into the cooling water return section will increase the temperature of the liquid at the cooling water return section, thereby achieving a balance between the heating demand on the condenser side and the cooling demand on the evaporator side, and avoiding too low a liquid temperature at the cooling water supply section of the refrigeration circuit. On the other hand, passing the liquid in the cooling water return section into the dynamic water tank can reduce the water temperature in the dynamic water tank, thereby achieving the effect of cold storage.

[0070] The chilled water pump arranged in the refrigeration return water section can be used to pump the liquid in the dynamic water tank into the refrigeration return water section, so that the liquid in the dynamic water tank is replaced with the refrigeration return water section.

[0071] Since the dynamic water tank is connected to the heating return water section and the cooling return water section respectively, not only can the dynamic water tank be used to adjust the liquid temperature of the heating return water section and the cooling return water section to ensure the normal operation of the heat recovery unit, but the cooling return water section and the heating return water section can also be used to adjust the water temperature in the dynamic water tank, so that the liquid temperature in the dynamic water tank is always maintained between the water temperature of the cooling return water section and the water temperature of the heating return water section, thereby satisfying both the heating return water section temperature increase and the heating return water section temperature decrease. The dynamic water tank has a stronger adjustment ability than a water tank that is connected to a single cooling return water section or a single heating return water section. Generally speaking, there is no need to set up heat exchange equipment to adjust the temperature of the dynamic water tank, which reduces the energy consumption of the heat recovery system.

[0072] See also Figures 1 to 4 As shown, in some implementations, when the heating water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0073] Obtain the cooling demand of the heating return water section and the maximum cooling capacity of the dynamic water tank;

[0074] Determine whether the maximum cooling capacity of the dynamic water tank meets the cooling demand of the heating return water section;

[0075] If the maximum cooling capacity of the dynamic water tank cannot meet the cooling demand of the heating return water section, the cooling tower is controlled to cool the liquid in the dynamic water tank.

[0076] It is understandable that since the dynamic water tank cools the liquid in the heating return water section by replacing the liquid in the heating return water section, the cooling effect of the dynamic water tank on the heating return water section can be adjusted by adjusting the flow rate of the replacement liquid. When the flow rate of the replacement liquid is adjusted to the flow rate of the heating return water section, the cooling effect can no longer be improved by the dynamic water tank itself, and the dynamic water tank is at its maximum cooling capacity.

[0077] In order to further enhance the cooling effect on the heating return water section, in this embodiment, the temperature of the liquid in the low dynamic water tank is lowered by a cooling tower, which can increase the temperature difference between the liquid in the dynamic water tank and the liquid in the heating return water section, thereby enhancing the cooling effect of the dynamic water tank on the heating return water section.

[0078] In some implementations, the cooling demand of the heating return water section is calculated according to the following formula:

[0079] P q冷 -P 2热 =P 2冷

[0080] Among them, P1冷 is the cooling demand of the refrigeration circuit, P 2热 is the heating demand of the heating circuit, P 2冷 The cooling demand of the heating return water section. In other words, the cooling demand of the heating return water section is related to the cooling demand of the refrigeration circuit and the heating demand of the heating circuit. By meeting the cooling demand of the heating return water section through the dynamic water tank, the demand of the condenser side and the evaporator side of the heat recovery unit can be balanced, so that the hot water flowing out of the heating water supply section and the cold water flowing out of the cooling water supply section can meet the corresponding temperature requirements respectively.

[0081] In some implementations, the maximum cooling capacity of the dynamic water tank is calculated as follows:

[0082] P 回冷 =Cp*r*Vs thermal recovery*ΔT1

[0083] Among them, P is the maximum cooling capacity of the dynamic water tank, Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT1=T 热回 -T 动 , T 热回 is the temperature of the liquid at the inlet of the heating return water section, T 动 is the temperature of the liquid in the dynamic water tank.

[0084] The specific gravity here is equivalent to the density of the liquid under a specific pressure, and the specific heat is equivalent to the specific heat capacity of the liquid under the corresponding pressure. The above formula can be used to calculate the maximum cooling amount that the dynamic water tank can provide for the heating return water section per unit time, so as to reflect the maximum cooling capacity of the dynamic water tank.

[0085] It should be noted that the liquid in the dynamic water tank, the liquid in the heating circuit and the liquid in the refrigeration circuit are of the same type, have the same constant pressure specific heat Cp and the same specific weight r.

[0086] In some implementations, when the refrigeration water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0087] Obtain the heating demand of the refrigeration return water section and the maximum heating capacity of the dynamic water tank;

[0088] Determine whether the maximum heating capacity of the dynamic water tank meets the heating requirements of the refrigeration return water section;

[0089] When the maximum heating capacity of the dynamic water tank cannot meet the heating demand of the refrigeration return water section, the cooling tower is controlled to heat the liquid in the dynamic water tank.

[0090] That is to say, since the flow rate of liquid that the dynamic water tank can pass into the refrigeration return section is limited, when the liquid flow rate of the dynamic water tank replacing the refrigeration return section is set to the flow rate of the refrigeration return section, the heating capacity of the dynamic water tank for the refrigeration return section reaches the maximum.

[0091] If the heating capacity of the dynamic water tank still cannot meet the heating demand of the refrigeration return water section at this time, the cooling tower is controlled to heat the liquid in the dynamic water tank to increase the temperature difference of the liquid and thus improve the heating effect of the refrigeration circuit.

[0092] In some implementations, the heating demand of the heating circuit is calculated according to the following formula:

[0093] P 2热 =Cp*r*Vs thermal return*ΔT2;

[0094] Where Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT2=T 供热 -T 热回 , T 热回 is the temperature of the liquid at the inlet of the heating return water section, T 供热 The set liquid heating temperature for the heating circuit.

[0095] It indicates how much heat needs to be supplied to the heating circuit per unit time to maintain the water temperature of the heating water supply section at T when the temperature difference between the heating water supply section and the heating water return section of the refrigeration circuit reaches ΔT2. 供热 , so that the heating circuit can meet the requirements.

[0096] The principle is the same, and the refrigeration demand of the refrigeration circuit is calculated according to the following formula:

[0097] P 1冷 =Cp*r*Vs cold return*ΔT1,

[0098] Where Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs cold return is the flow rate of the refrigeration circuit, ΔT1 = T 冷回 -T 供冷 , T 冷回 is the temperature of the liquid at the inlet of the refrigeration return water section, T 供冷 The liquid cooling temperature is set for the cooling water supply section. The liquid in the dynamic water tank is the same as the liquid in the refrigeration circuit.

[0099] It indicates how much cooling capacity needs to be provided to the refrigeration circuit per unit time to maintain the water temperature of the refrigeration water supply section at T when the temperature difference between the refrigeration water supply section and the refrigeration water return section of the refrigeration circuit reaches ΔT1. 供冷 , so that the refrigeration circuit can meet the requirements.

[0100] In some implementations, when the heating water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0101] Obtaining the liquid temperature of the heating circuit at the heating water supply section;

[0102] When the liquid temperature of the heating water supply section is lower than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to decrease;

[0103] When the liquid temperature of the heating water supply section is higher than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to increase.

[0104] That is to say, according to the liquid temperature at the heating water supply section, the liquid replacement amount between the dynamic water tank and the heating water return section is adjusted so that the liquid temperature at the heating water supply section is stabilized at the set heating temperature. Specifically, a three-way valve V3 and a three-way valve V4 are provided between the dynamic water tank and the heating water return section. By increasing the opening of the three-way valve V3 and the three-way valve V4, the liquid replacement amount can be increased to reduce the temperature of the heating water supply section, or by decreasing the opening of the three-way valve V3 and the three-way valve V4, the liquid replacement amount can be reduced to increase the temperature of the heating water supply section.

[0105] In some implementations, when the refrigeration water return section is connected to the dynamic water tank, the control method further includes the following steps:

[0106] Obtain the liquid temperature of the refrigeration circuit at the refrigeration water supply section;

[0107] When the liquid temperature of the cooling water supply section is lower than the set cooling temperature, the liquid replacement amount between the dynamic water tank and the cooling water return section is controlled to increase;

[0108] When the liquid temperature of the refrigeration water supply section is higher than the set refrigeration supply temperature, the liquid replacement amount between the dynamic water tank and the refrigeration return water section is controlled to decrease.

[0109] That is to say, according to the liquid temperature at the cooling water supply section, the liquid replacement amount between the dynamic water tank and the cooling water return section is adjusted so that the liquid temperature at the cooling water supply section is stabilized at the set cooling temperature. Specifically, a three-way valve V1 and a three-way valve V2 are provided between the dynamic water tank and the cooling water return section. By increasing the opening of the three-way valve V1 and the three-way valve V2, the liquid replacement amount is increased to increase the temperature of the cooling water supply section, or by decreasing the opening of the three-way valve V1 and the three-way valve V2, the liquid replacement amount is reduced to reduce the temperature of the cooling water supply section.

[0110] In some implementations, the control method further includes the following steps:

[0111] Determine whether the difference between the heating demand and the cooling demand is greater than the fluctuation threshold;

[0112] When the difference between the heating demand and the cooling demand is less than the fluctuation threshold, the heating return water section and the cooling return water section are controlled to be disconnected from the dynamic water tank respectively.

[0113] That is to say, when the difference between heating demand and cooling demand is small, the dynamic water tank is not connected to the water circuit. The specific fluctuation threshold is cooling demand * 5%.

[0114] In some implementations, the control method further includes the following steps:

[0115] When the heating circuit has no heating demand and the refrigeration circuit has refrigeration demand, the cooling tower is controlled to be connected to the condensation side to dissipate heat from the condensation side;

[0116] When the heating circuit has a heating demand and the refrigeration circuit has no refrigeration demand, the cooling tower is controlled to be connected to the evaporation side to increase the temperature of the evaporation side.

[0117] That is to say, when there is only one of the heating demand and the cooling demand, the dynamic water tank is not connected to the heating circuit or the cooling circuit, but the cooling tower is used to dissipate heat or increase temperature, which can dissipate heat or increase temperature faster and improve heat exchange efficiency.

[0118] See also Figure 1 as well as Figure 2 As shown, in the second aspect, a heat recovery system is also provided, which includes: a heat recovery unit, which has a condensing side and an evaporating side; a heating circuit, which is connected to the condensing side; a refrigeration circuit, which is connected to the evaporating side; a dynamic water tank, the heating return water section of the heating circuit and the refrigeration return water section of the heating circuit are selectively connected to the dynamic water tank respectively; and a controller, the controller is electrically connected to the dynamic water tank, and the controller is used to execute the above-mentioned control method.

[0119] Specifically, when the heating demand of the heating water return section is less than the cooling demand of the cooling water return section, the controller controls the dynamic water tank to be connected with the heating water return section, so that at least part of the liquid in the heating water return section is replaced by the liquid in the dynamic water tank in equal amount, so as to reduce the liquid temperature at the end of the heating water return section;

[0120] When the heating demand of the heating return water section is greater than the cooling demand of the cooling return water section, the controller controls the dynamic water tank to be connected with the cooling return water section, so that the liquid in the cooling return water section is at least partially replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the cooling return water section.

[0121] By executing the above control method through the controller, the dynamic water tank can be used to achieve temperature regulation of the heating circuit and the refrigeration circuit, so that the condensing side and the evaporation side of the heat recovery unit are balanced, and the hot water supplied by the heating circuit and the cold water supplied by the refrigeration circuit meet the usage requirements.

[0122] Among them, the heating return water section of the heating circuit is provided with a three-way valve V3 and a three-way valve V4. When it is necessary to connect the dynamic water tank with the heating return water section, the controller opens the three-way valve V3 and the three-way valve V4, so that the liquid in the heating return water section can flow into the dynamic water tank, and the liquid in the dynamic water tank can flow into the heating return water section, so as to achieve equal replacement of the liquid in the heating return water section with the liquid in the dynamic water tank, and complete the cooling of the heating return water section. The amount of liquid replaced by the dynamic water tank to the heating return water section can be controlled by adjusting the opening of the three-way valve V3 and the three-way valve V4, and the cooling speed of the dynamic water tank on the heating return water section can be adjusted.

[0123] The refrigeration return water section of the refrigeration circuit is provided with a three-way valve V1 and a three-way valve V2. When it is necessary to connect the dynamic water tank with the refrigeration return water section, the controller opens the three-way valve V1 and the three-way valve V2, so that the liquid in the refrigeration return water section can flow into the dynamic water tank, and the liquid in the dynamic water tank can flow into the refrigeration return water section, so as to achieve equal replacement of the liquid in the refrigeration return water section with the liquid in the dynamic water tank, and complete the heating of the refrigeration return water section. The opening of the three-way valve V1 and the three-way valve V2 can be adjusted to control the amount of liquid replaced by the dynamic water tank to the refrigeration return water section, and adjust the heating speed of the dynamic water tank to the refrigeration return water section.

[0124] In order to accurately understand how much liquid flow needs to be replaced in the heating return water section, a temperature detection device is set at the inlet of the heating return water section to measure the water temperature T at the inlet of the heating return water section. 热回 A flow meter is provided on the heating circuit to measure the flow rate Vs of the heating circuit. 热回 .

[0125] A flow meter is installed on the refrigeration circuit to measure the flow rate Vs of the refrigeration circuit. 冷回 A temperature detection device is provided at the inlet of the refrigeration return water section to measure the liquid temperature at the inlet of the refrigeration return water section.

[0126] See also Figure 1 As shown, two groups of heat recovery units are provided in the heat recovery system to provide a more efficient heat recovery capability.

[0127] See also Figure 1 As shown, a cooling tower is also provided in the heat recovery system, and the cooling tower can be connected to the condensing side of the heat recovery unit. When the heat recovery unit only has a refrigeration demand, the controller controls the cooling tower to be connected to the condensing side of the heat recovery unit, and the controller also controls the cooling tower to absorb heat on the condensing side.

[0128] The cooling tower can also be connected to the dynamic water tank. When the maximum cooling capacity of the dynamic water tank for the heating return water section does not meet the cooling demand of the heating return water section, the controller connects the cooling tower with the dynamic water tank, and controls the cooling tower to cool down the dynamic water tank to enhance the cooling capacity of the dynamic water tank. Alternatively, when the maximum heating capacity of the dynamic water tank for the cooling return water section does not meet the heating demand of the cooling return water section, the controller controls the cooling tower to heat up the dynamic water tank to enhance the heating capacity of the dynamic water tank for the cooling return water section.

[0129] The cooling tower can also be connected to the evaporation side of the heat recovery unit. When the heat recovery unit only has heating demand, the controller controls the cooling tower to be connected to the evaporation side of the heat recovery unit. The controller also controls the cooling tower to remove heat from the evaporation side.

[0130] A heat recovery circulation pump is provided at the heating return water section of the heating circuit, which can not only realize the water circulation of the heating circuit, but also assist in pumping the water in the dynamic water tank into the heating return water section, thereby realizing the replacement of the water in the dynamic water tank with the water in the heating return water section.

[0131] Similarly, a chilled water pump is provided at the refrigeration return water section of the refrigeration circuit, which can not only realize the water circulation of the refrigeration circuit, but also assist in pumping the water in the dynamic water tank into the refrigeration return water section, thereby realizing the replacement of the water in the dynamic water tank with the water in the refrigeration return water section.

[0132] In a third aspect, the present invention also provides an air conditioner, which includes the above-mentioned heat recovery system. The dynamic water tank can be used to adjust the temperature of the heating circuit and the refrigeration circuit, so that the condensation side and the evaporation side of the heat recovery unit are balanced, and the hot water supplied by the heating circuit and the cold water supplied by the refrigeration circuit meet the use requirements.

[0133] In a fourth aspect, the present invention further provides a storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements any one of the control methods in the first aspect.

[0134] The processor may include, but is not limited to, one or more processors or microprocessors, etc. Each processor may be an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a controller, a microcontroller, a microprocessor or other electronic components to execute the methods in the above embodiments.

[0135] The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof. The computer-readable storage medium may include, but is not limited to, for example, random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, computer storage media (such as hard disks, floppy disks, solid-state drives, removable disks, CD-ROMs, DVD-ROMs, Blu-ray disks, etc.).

[0136] The storage medium may also store at least one computer executable program / instruction, which may be, for example, a computer readable instruction. Computer readable storage media include, but are not limited to, for example, volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory (cache), etc. Computer readable storage media may include, for example, read-only memory (ROM), hard disk, flash memory, etc. For example, a non-transitory computer readable storage medium may be connected to a computing device such as a computer, and then, when the computing device runs the computer readable instructions stored on the computer readable storage medium, the various methods described above may be performed.

[0137] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A control method for a heat recovery system, characterized in that: The control method comprises the following steps: Obtain heating demand of the heating circuit and cooling demand of the cooling circuit; When the heating demand is less than the cooling demand, the heating return water section is connected to the dynamic water tank, so that at least part of the liquid in the heating return water section is replaced by the liquid in the dynamic water tank, so as to reduce the liquid temperature at the end of the heating return water section; When the cooling demand is less than the heating demand, the refrigeration return water section is connected to the dynamic water tank so that at least part of the liquid in the refrigeration return water section is replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the refrigeration return water section. The dynamic water tank corresponding to the heating return water section and the dynamic water tank corresponding to the refrigeration return water section are the same dynamic water tank.

2. The control method according to claim 1, characterized in that: When the heating water return section is connected to the dynamic water tank, the control method further includes the following steps: Obtain the cooling demand of the heating return water section and the maximum cooling capacity of the dynamic water tank; Determine whether the maximum cooling capacity of the dynamic water tank meets the cooling demand of the heating return water section; If the maximum cooling capacity of the dynamic water tank cannot meet the cooling demand of the heating return water section, the cooling tower is controlled to cool the liquid in the dynamic water tank.

3. The control method according to claim 2, characterized in that: The cooling demand of the heating return water section is calculated according to the following formula: P 1冷 -P 2热 =P 2冷 Among them, P 1冷 is the cooling demand of the refrigeration circuit, P 2热 is the heating demand of the heating circuit, P 2冷 It is the cooling demand of the heating return water section.

4. The control method according to claim 2, characterized in that: The maximum cooling capacity of the dynamic water tank is calculated according to the following formula: P 回冷 =Cp*r*Vs thermal recovery*ΔT1 Among them, P is the maximum cooling capacity of the dynamic water tank, Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT1=T 热回 -T 动 , T 热回 is the temperature of the liquid at the inlet of the heating return water section, T 动 is the temperature of the liquid in the dynamic water tank.

5. The control method according to any one of claims 1 to 4, characterized in that: When the refrigeration return water section is connected to the dynamic water tank, the control method further includes the following steps: Obtain the heating demand of the refrigeration return water section and the maximum heating capacity of the dynamic water tank; Determine whether the maximum heating capacity of the dynamic water tank meets the heating requirements of the refrigeration return water section; When the maximum heating capacity of the dynamic water tank cannot meet the heating demand of the refrigeration return water section, the cooling tower is controlled to heat the liquid in the dynamic water tank.

6. The control method according to any one of claims 1 to 4, characterized in that: The heating demand of the heating circuit is calculated according to the following formula: P 2热 =Cp*r*Vs thermal return*ΔT2; Where Cp is the constant pressure specific heat of the liquid in the dynamic water tank, r is the specific weight of the liquid in the dynamic water tank, Vs 热回 is the flow rate of the heating circuit, ΔT2=T 供热 -T 热回 , T 热回 is the temperature of the liquid at the inlet of the heating return water section, T 供热 The liquid heating temperature is set for the heating return section. The liquid in the dynamic water tank is the same as the liquid in the heating circuit.

7. The control method according to any one of claims 1 to 4, characterized in that: When the heating water return section is connected to the dynamic water tank, the control method further includes the following steps: Obtaining the liquid temperature of the heating circuit at the heating water supply section; When the liquid temperature of the heating water supply section is lower than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to decrease; When the liquid temperature of the heating water supply section is higher than the set heating temperature, the liquid replacement amount between the dynamic water tank and the heating return water section is controlled to increase.

8. The control method according to any one of claims 1 to 4, characterized in that: The control method also includes: Determine whether the difference between the heating demand and the cooling demand is greater than the fluctuation threshold; When the difference between the heating demand and the cooling demand is less than the fluctuation threshold, the heating return water section and the cooling return water section are controlled to be disconnected from the dynamic water tank respectively.

9. The control method according to any one of claims 1 to 4, characterized in that: The control method further comprises the following steps: When the heating circuit has no heating demand and the refrigeration circuit has refrigeration demand, the cooling tower is controlled to be connected to the condensation side to dissipate heat from the condensation side; When the heating circuit has a heating demand and the refrigeration circuit has no refrigeration demand, the cooling tower is controlled to be connected to the evaporation side to increase the temperature of the evaporation side.

10. A heat recovery system, characterized in that: These include, A heat recovery unit having a condensing side and an evaporating side; A heating circuit, which is connected to the condensation side; a refrigeration circuit, which is in communication with the evaporation side; A dynamic water tank, the heating water return section of the heating circuit and the cooling water return section of the cooling circuit are selectively connected to the dynamic water tank respectively; and a controller, the controller being electrically connected to the dynamic water tank; When the heating demand of the heating water return section is less than the cooling demand of the cooling water return section, the controller controls the dynamic water tank to be connected with the heating water return section, so that at least part of the liquid in the heating water return section is replaced by the liquid in the dynamic water tank in equal amount, so as to reduce the liquid temperature at the end of the heating water return section; When the heating demand of the heating return water section is greater than the cooling demand of the cooling return water section, the controller controls the dynamic water tank to be connected with the cooling return water section, so that the liquid in the cooling return water section is at least partially replaced by the liquid in the dynamic water tank to increase the liquid temperature at the end of the cooling return water section.

11. The heat recovery system according to claim 10, characterized in that: Also included is a cooling tower, the cooling tower being electrically connected to the controller; When the heating circuit has no heating demand and the refrigeration circuit has refrigeration demand, the cooling tower is controlled to be connected to the condensation side to dissipate heat from the condensation side; When the heating circuit has a heating demand and the refrigeration circuit has no refrigeration demand, the cooling tower is controlled to be connected to the evaporation side to increase the temperature of the evaporation side.

12. An air conditioner, characterized in that: It comprises the heat recovery system according to claim 10 or 11.

13. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method according to any one of claims 1 to 9 is implemented.

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