TWI551836B - Control method for flow balance - Google Patents

Description

Flow balance control method

The invention relates to a flow balance control method, in particular to a flow balance control method suitable for an ice water system.

In recent years, large buildings have mostly used refrigerated air conditioners to adjust the temperature inside the building and to circulate the air inside the building. In order to meet the demand for energy saving, the current refrigerating air conditioner is mainly a composite ice-water system (multiple-chiller system). The composite ice water host system generally includes a plurality of primary pumps, a plurality of ice water hosts, and a plurality of secondary pumps. These ice water hosts connect these primary pumps separately. These secondary pumps are in communication with these ice water hosts. Each of the primary pumps is used to transfer high temperature water to the ice water main unit. Each ice water main unit is used to turn hot water into ice water. Each secondary pump is used to transfer the ice water generated by the ice water main unit to each working chamber in the building for heat exchange.

Each ice water host has a corresponding load energy consumption curve characteristic. When the load rate of the ice water host falls within the section with the least energy consumption in the load energy consumption curve, the power consumption of the ice water host can be greatly reduced. However, since the models and flow resistances of the ice water main engines are different, the ice water main engines have different load rates during operation. That is to say, when the composite ice water host system is actually operating, it is often the case that some ice water hosts are at a low load, and some ice water hosts are at a high level. load. However, the preferred load energy consumption range (lower and more energy-saving) of the ice water host is generally between 50% and 90%, so as long as the load rate of the ice water host is higher than 90% or lower than 50. % will increase the power consumption of the refrigerated air conditioner. Therefore, how to control the load rate of each ice water host falls within the range of better load energy consumption is the goal that the manufacturer should pursue.

The invention provides a flow balance control method for controlling the load rate of each ice water host to fall within a better load energy consumption range.

The flow balance control method disclosed in the present invention is applicable to an ice water system. The ice water system consists of a number of ice machines (Water Chiller) and multiple primary pumps. These ice machines are connected to these primary pumps separately. The primary pumps are respectively located on the return water side of the ice machines, and the steps of the flow balance control method include adjusting the water temperature and return water of the ice machines according to the respective load rate differences between the load rate and the average load rate of the ice machines. The temperature difference between the temperatures increases the temperature difference of the ice machines whose load rate is greater than the average load rate, and the temperature difference of the ice machines whose load ratio is smaller than the average load rate. Next, the flow rates of these primary pumps are calculated based on these temperature differences, and the flow rates of these primary pumps are adjusted to bring the load rates of these ice machines closer to the average load rate.

The flow balance control method disclosed in the present invention is applicable to an ice water system. The ice water system consists of multiple ice machines and multiple primary pumps. These ice machines are connected to these primary pumps separately. These primary pumps are located on the return water side of these ice machines, and the steps of the flow balance control method include the load rate based on the ice machines. The respective load rate differences between the average load rates adjust the respective operating frequencies of the primary pumps, reduce the operating frequency of the primary pumps corresponding to the ice machines whose load ratio is greater than the average load rate, and increase the load rate to be less than the average load rate. These ice machines correspond to the operating frequency of the primary pumps, so that the load rate of these ice machines approaches the average load rate.

The flow balance control method disclosed in the present invention is applicable to an ice water system. The ice water system consists of multiple ice machines and multiple primary pumps. These ice machines are connected to these primary pumps separately. The primary pumps are respectively located on the return water side of the ice machines. The flow balance control method comprises the steps of respectively adjusting the operating frequencies of the primary pumps according to the respective flow rates of the primary pumps and the corresponding preset flow rates, and reducing the flow rate to be greater than the preset. The operating frequency of these primary pumps of the flow rate, and the operating frequency of the primary pumps that increase the flow rate less than the preset flow rate, so that the load rate of these ice machines approaches the average load rate of one of the ice machines.

According to the flow balance control method disclosed in the above invention, by adjusting the temperature difference of the ice machine, the operating frequency of the primary pump or the flow rate of the primary pump, the load rate of each ice machine can approach the average load rate of each ice machine. In order to make the load rate of each ice machine fall within the range of better load energy consumption as much as possible, thereby reducing the overall power consumption of each ice machine.

The above description of the present invention and the following description of the embodiments are intended to illustrate and explain the principles of the invention, and to provide a further explanation of the scope of the invention.

10‧‧‧Ice Water System

100‧‧‧primary pump

200‧‧‧ ice machine

300‧‧‧Secondary pump

400‧‧‧Refrigeration air-conditioned room

500‧‧‧ controller

Fig. 1 is a system diagram of an ice water system to which a flow balance control method is applied according to a first embodiment of the present invention.

Fig. 2 is a graph showing the relationship between the load factor and the energy consumption of the ice machine of Fig. 1.

Fig. 3 is a flow chart showing a flow balance control method for controlling an ice water system according to a first embodiment of the present invention.

Fig. 4 is a flow chart showing a flow balance control method for controlling an ice water system according to a first embodiment of the present invention.

Fig. 5 is a flow chart showing a flow balance control method for controlling an ice water system according to a second embodiment of the present invention.

Fig. 6 is a flow chart showing a flow balance control method for controlling an ice water system according to a second embodiment of the present invention.

Fig. 7 is a flow chart showing a flow balance control method for controlling an ice water system according to a third embodiment of the present invention.

Fig. 8 is a flow chart showing a flow balance control method for controlling an ice water system according to a third embodiment of the present invention.

Please refer to FIG. 1 and FIG. 2 . FIG. 1 is a schematic diagram of a system of an ice water system suitable for a flow balance control method according to a first embodiment of the present invention, and FIG. 2 is a load rate and consumption of the ice machine of FIG. 1 . A graph of the relationship between energy. The operation principle of the ice water system 10 will be described below.

Referring to FIG. 1 , the ice water system 10 includes a plurality of primary pumps 100 , a plurality of ice machines 200 , a plurality of secondary pumps 300 , at least one refrigeration air conditioning room 400 , and a controller 500 .

Each of the primary pumps 100 is in communication with each other. Each of the primary pumps 100 may further include at least one sensor (not shown) for sensing information such as the flow rate, operating frequency or load rate of the primary pump 100. In the present embodiment, the primary pump 100 is, for example, a variable frequency pump.

Each of the ice machines 200 is connected to each of the primary pumps 100 in a one-to-one manner, and the primary pumps 100 are located on the water supply side (return water side or primary side) of the ice machine 200. Each ice machine 200 can also include at least one sensor (not shown) for sensing information such as the return water temperature, the water temperature or the load rate of the ice machine 200. The ice machine 200 is used to generate ice water, for example, to reduce water of about 20 degrees Celsius to ice water of about 10 degrees Celsius. In addition, the ice machine 200 has a load rate when it is in operation. The load rate of the ice machine 200 is defined as the ratio between the actual power consumption of the ice machine 200 and the maximum power consumption. The average load rate of each ice machine 200 is the average of the load rates of the ice machines 200. Each ice machine 200 has a preferred load energy consumption range R. When the load rate of the ice machine 200 falls within the preferred load energy consumption range R, the power consumption of the ice machine 200 is small. In general, when the load rate of the ice machine 200 is between 50% and 90%, the corresponding power consumption is small, which is less than about 0.94 kW/ton (as shown in Fig. 2).

Each of the secondary pumps 300 is connected to each ice machine 200, and the secondary pump 300 is located on the water outlet side (secondary side) of the ice machine 200.

The refrigerating air conditioning room 400 is in communication with at least one secondary pump 300. cold The air in the air-conditioned room 400 is used for heat exchange with the ice water produced by the ice machine 200 to achieve the effect of the refrigerating air conditioner.

The controller 500 is coupled to each primary pump 100 and each ice machine 200 for receiving information such as the flow rate, operating frequency or load rate of each primary pump 100, and the return water temperature, the outlet water temperature or the load rate of each ice machine 200, and the like. Information and control each pump 100 based on this information.

When the ice water system 10 is in operation, the primary pump 100 is used to send water (relatively high temperature) circulating from the refrigerating and air-conditioning room 400 to the ice machine 200. Next, the ice machine 200 converts the water fed from the primary pump 100 into ice water (the temperature is relatively low) via heat exchange. Next, the secondary pump 300 transfers the ice water to the freezing air-conditioned room 400 to achieve the effect of the refrigerating air conditioner.

The required cooling rate of the refrigerating and air conditioning room 400 (load end) affects the load rate of each ice machine 200. That is to say, the greater the cooling rate required for the refrigerating and air-conditioning room 400, the higher the total load rate of each ice machine 200. In addition, the load rate of each ice machine 200 is related to the flow rate provided by the primary pump 100. When the flow rate of the primary pump 100 is increased, the ice machine 200 can generate more ice water per unit time, but the load rate is relatively increased. Since the flow rate supplied by each primary pump 100 cannot be consistent, and the performance of the ice making water of each ice machine 200 is also different, the load rate of each ice machine 200 cannot be kept consistent. As a result, the load rate of the partial ice machine 200 is greater than the preferred load energy consumption range R, and the load rate of the partial ice machine 200 is less than the preferred load energy consumption range R. However, as long as the load rate of the ice machine 200 falls outside the preferred load energy consumption range R, the power consumption of the ice machine 200 The amount will increase.

Next, how to adjust the load ratio of the ice machine 200 to the better load energy consumption range R through the flow balance control method of the embodiment, thereby reducing the overall power consumption of each ice machine.

Please refer to FIG. 3 and FIG. 4, FIG. 3 is a schematic flow chart of a flow balance control method for controlling an ice water system according to a first embodiment of the present invention, and FIG. 4 is a control ice water according to a first embodiment of the present invention. Schematic diagram of the flow balance control method of the system.

Referring to FIG. 3, first, as shown in step S100, the controller 500 calculates an average load rate of one of the ice machines 200 according to the load rate of each ice machine 200.

Next, as shown in step S200, the controller 500 adjusts the ice machines 200 according to the respective load ratio differences (the difference between the load rate and the average load rate) between the load rate and the average load rate of the ice machines 200. The temperature difference between the outlet water temperature and the return water temperature. The controller 500 is configured to increase the temperature difference of the ice machines 200 whose load rate is greater than the average load rate, and to reduce the temperature difference of the ice machines 200 whose load rate is less than the average load rate. The temperature difference is the difference between the temperature of the water return side of the ice machine 200 and the temperature of the water outlet side.

Next, the controller 500 calculates the flow rates of the primary pumps 100 according to the temperature difference between the water outlet temperature and the return water temperature of the ice machines 200, and adjusts the flow rates of the primary pumps 100 to increase the load rate of the ice machines 200. Approach the average load rate.

Next, it is further explained how the controller 500 controls the load rate of each ice machine 200 to approach the average load rate. In step S200, the controller 500 adjusts the temperature difference between the water outlet temperature and the return water temperature of the ice machine 200 according to the respective load rate differences between the load rate and the average load rate of the ice machine 200. Referring to FIG. 4, as shown in step S210, when the absolute value of the load rate difference of at least one ice machine 200 is greater than a first threshold, the controller 500 is configured to make the ice machines having a load rate greater than the average load rate. The temperature difference between the outlet water temperature and the return water temperature of 200 is increased by a first preset value, and the temperature difference between the outlet water temperature and the return water temperature of the ice machine 200 having the load ratio less than the average load rate is decreased by the first Set the value.

Then, as shown in step S220, when the absolute value of the load rate difference of at least one ice machine 200 is between the first threshold value and a second threshold value that is less than one of the first threshold values, the controller 500 is configured to: The temperature difference between the water outlet temperature and the return water temperature of the ice machines 200 having a load ratio greater than the average load rate is increased by a second preset value, and the water outlet temperature and return water of the ice machines having the load rate less than the average load rate The temperature difference between the temperatures is decreased by a second preset value.

Next, as shown in step S230, when the absolute value of the load rate difference of at least one ice machine 200 is between the second threshold value and a third threshold value less than the second threshold value, the controller is configured to load The temperature difference between the water outlet temperature and the return water temperature of the ice machines 200 having a rate greater than the average load rate is increased by a third preset value, and the ice machines 200 having the load rate less than the average load rate are used. The temperature difference between the outlet water temperature and the return water temperature is decreased by a third preset value.

In this embodiment, the first threshold is 3 percentage (%), the second threshold is 2% (%), the first threshold is a percentage (%), and the first preset value is 1 degree Celsius, The second preset value is 0.75 degrees Celsius and the third preset value is 0.5 degrees Celsius. Therefore, the load ratio difference between the load rate and the average load rate of each ice machine 200 can be made close to zero through steps S210 to S230, that is, the load rate of each ice machine 200 approaches the average load rate, thereby The load rate of each ice machine 200 can fall within the preferred load energy consumption range R as much as possible to reduce the overall power consumption of each ice machine 200. In addition, the threshold values (3%, 2%, and 1%) and the preset values (01, 0.75, and 0.5) are not used for limitation. In other embodiments, the threshold value and the preset value may also be other. Any value.

For example, first assume that the load rate of the controller 500 to the seven ice machines 200 is 70%, 100%, 95%, 65%, 10%, 50%, and 100%, respectively. Then the average load rate of the seven ice machines 200 is 70%. Then, since the absolute value of the load ratio difference between the load rate of the at least one ice machine 200 and the average load rate is greater than 3%, the controller 500 is respectively used to make the ice machines 200 with load ratios greater than the average load rate (load The temperature difference between the outlet temperature and the return water temperature of the 100% and 95% ice machine 200) continuously increases by the first preset value (1 degree Celsius). Next, when the absolute value of the load rate difference of the ice machine 200 is between 2% and 3%, the controller 500 continues to increase the temperature difference between the water temperature and the return water temperature of the ice machine 200 by the second pre- Set value (0.75 degrees Celsius). Next, when the absolute value of the load rate difference of the ice machine 200 is between 1% and 2%, the controller 500 causes the ice machines 200 to The temperature difference between the outlet water temperature and the return water temperature continues to increase by a third preset value (0.5 degrees Celsius).

In addition, the controller 500 is configured to reduce the temperature difference between the water outlet temperature and the return water temperature of the ice machines 200 (the ice machines 200 with load ratios of 65%, 10%, and 50%) having a load ratio lower than the average load rate. The first preset value (1 degree Celsius). Next, when the absolute value of the load rate difference of the ice machine 200 is between 2% and 3%, the controller 500 keeps the temperature difference between the water temperature and the return water temperature of the ice machines 200 continuously decreased by the second pre- Set value (0.75 degrees Celsius). Then, when the absolute value of the load rate difference of the ice machine 200 is between 1% and 2%, the controller 500 keeps the temperature difference between the water temperature and the return water temperature of the ice machines 200 continuously decreased by the third pre- Set value (0.5 degrees Celsius)

Next, please match the thermodynamic formula Q _i =M _i ×S×Δt _i . Where i is a positive integer from 1 to 7, Q _i is the heat to be removed from the i-th ice machine 200, M _i is the flow provided by the i-th primary pump 100, S is the specific heat coefficient, and Δt _i is The temperature difference between the return water temperature and the outlet water temperature of the i-th ice machine 200. On the premise that the amount of heat to be removed by the ice machine is a fixed value. When the controller 500 increases the temperature difference between the outlet temperature and the return water temperature of the ice machines 200 (load rate 100% and 95% ice machine 200) whose load rate is greater than the average load rate, the corresponding primary pump is reduced. 100 traffic. When the flow rate of the primary pump 100 decreases, the load rate (100% and 95%) of the corresponding ice machine 200 approaches the average load rate (70%). Next, with the second figure, when the load rate of the ice machine 200 is reduced from 100% to 70%, the power consumption of the ice machine 200 will be reduced from 1 kW/ton to 0.92 kW/ton.

In addition, when the controller 500 reduces the temperature difference between the water outlet temperature and the return water temperature of the ice machines (the load rate is 100% and 95% of the ice machine 200) whose load rate is less than the average load rate, the corresponding one is increased. The flow rate of the pump 100. When the flow rate of the primary pump 100 increases, the load rate (10%, 50%, and 65%) of the corresponding ice machine 200 approaches the average load rate (70%). Next, with the second figure, when the load rate of the ice machine 200 is increased from 10% to 70%, the power consumption of the ice machine 200 will be reduced from 2 kW/ton to 0.92 kW/ton.

From the above example, the flow balance control method of the present embodiment causes the controller 500 to control the temperature difference between the water outlet temperature and the return water temperature of the ice machine 200 to greatly reduce the power consumption of the ice machine 200.

The above-mentioned flow balance control method adjusts the flow rate of the primary pump 100 by controlling the temperature difference between the outlet water temperature and the return water temperature of the ice machine 200, thereby reducing the power consumption of the ice machine 200, but is not limited thereto. In other embodiments, the flow balance control method can also reduce the power consumption of the ice machine 200 directly by controlling the operating frequency of the primary pump 100. Please refer to Figure 5 and Figure 6. 5 is a flow chart showing a flow balance control method for controlling an ice water system according to a second embodiment of the present invention, and FIG. 6 is a flow chart showing a flow balance control method for controlling an ice water system according to a second embodiment of the present invention. This embodiment is similar to the embodiment of Fig. 3, and therefore only the differences will be described.

Referring to FIG. 5, first, as shown in step S400, the controller 500 calculates an average load ratio of one of the ice machines 200 according to the load rate of each ice machine 200.

Next, as shown in step 500, the controller 500 adjusts the respective operating frequencies of the primary pumps 100 according to the respective load rate differences between the load rate and the average load rate of the ice machines 200. The frequency of operation of these primary pumps 100 is proportional to the flow provided by these primary pumps. The controller 500 is configured to reduce the operating frequency of the ice pump 200 corresponding to the primary pump 100 with the load rate greater than the average load rate, and increase the operating frequency of the ice pump 200 corresponding to the primary pump 100 by increasing the load rate less than the average load rate. In order to bring the load rate of these ice machines closer to the average load rate.

Next, it is further explained how the controller 500 controls the load rate of each ice machine 200 to approach the average load rate. In step S500, the controller 500 adjusts the operating frequencies of the ice machines 200 according to the respective load rate differences of the load rate and the average load rate of the ice machines 200. The method further includes: refer to FIG. 6, as shown in step S510. When the absolute value of the load ratio difference of at least one ice machine 200 is greater than a first threshold, the controller 500 is configured to reduce the operating frequency of the primary pump corresponding to the ice machines 200 having a load ratio greater than the average load rate. A first preset value, and an operating frequency of the ice pump 200 corresponding to the load rate being less than the average load rate corresponding to the primary pump 100 is increased by a first predetermined value.

Next, as shown in step S520, when the absolute value of the load rate difference of at least one ice machine 200 is between the first threshold value and a second threshold value that is less than one of the first threshold values, the controller 500 is configured to: The operation frequency of the primary pump 100 corresponding to the ice machines with the load rate greater than the average load rate is reduced by a second The preset value, and the operating frequency of the ice pump 200 corresponding to the load rate being less than the average load rate, is increased by a second preset value.

Then, as shown in step S530, when the absolute value of the load rate difference of at least one ice machine 200 is between the second threshold value and a third threshold value that is less than the second threshold value, the controller 500 is configured to: The operating frequency of the ice pump 200 corresponding to the average load rate is reduced by a third preset value, and the operating frequency of the ice pump 200 corresponding to the average load rate is corresponding to the primary pump. Increase the third preset value.

In the above embodiment, the flow balance control method is based on the load rate of the ice machine 200, but is not limited thereto. In other embodiments, the flow balance control method may also use the flow rate of the primary pump 100 as a control reference. .

Please refer to FIG. 7 and FIG. 8 , FIG. 7 is a schematic flow chart of a flow balance control method for controlling an ice water system according to a third embodiment of the present invention, and FIG. 8 is a diagram for controlling ice water according to a third embodiment of the present invention. Schematic diagram of the flow balance control method of the system. This embodiment is similar to the embodiment of Fig. 5, and therefore only the differences will be described.

Referring to FIG. 7, first, as shown in step S600, the controller 500 adjusts the respective operating frequencies of the primary pumps 100 according to the respective flows of the primary pumps 100 and the corresponding preset flows. The respective operating frequencies of these primary pumps 100 are proportional to the flow rates provided by these primary pumps 100. The controller 500 is configured to reduce the operating frequency of the primary pumps 100 whose flow rate is greater than the preset flow rate, and increase the operating frequency of the primary pumps 100 whose flow rate is less than the preset flow rate. The loading rate of these ice machines 200 is approached to an average load rate of one of these ice machines 200.

Next, it is further explained how the controller 500 controls the load rate of each ice machine 200 to approach the average load rate. In step S600, the controller 500 separately adjusts the operating frequencies of the primary pumps 100 according to the respective flow rates of the primary pumps 100 and the corresponding preset flow rates, and further includes: refer to FIG. 8, as shown in step S610, when When the absolute value of the difference between the flow rate of the primary pump 100 and the preset flow rate is greater than a first threshold value, the controller 500 is configured to reduce the operating frequency of the primary pumps 100 whose flow rate is greater than the preset flow rate by one first The set value and the operating frequency of the primary pumps 100 that cause the flow to be less than the preset flow rate are increased by a first predetermined value.

Then, as shown in step S620, when the absolute value of the difference between the flow rate of the at least one primary pump 100 and the preset flow rate is between the first critical value and a second critical value less than the first critical value, the control The device 500 is configured to reduce the operating frequency of the primary pumps 100 whose flow rate is greater than the preset flow rate by a second preset value, and to increase the operating frequency of the primary pumps 100 whose flow rate is less than the preset flow rate by a second predetermined value.

Then, as shown in step S630, when the absolute value of the difference between the flow rate of the at least one primary pump 100 and the preset flow rate is between the second critical value and a third critical value less than the second critical value, the control The device 500 is configured to reduce the operating frequency of the primary pumps 100 whose flow rate is greater than the preset flow rate by a third preset value, and to reduce the operating frequency of the primary pumps 100 whose flow rate is less than the preset flow rate. The rate is increased by a third preset value.

According to the flow balance control method disclosed in the above invention, the controller adjusts the load ratio of each ice machine by adjusting the temperature difference between the water outlet temperature and the return water temperature of the ice machine, the operating frequency of the primary pump or the flow rate of the primary pump. The average load rate of each ice machine can be approached to make the load rate of each ice machine fall within the range of better load energy consumption as much as possible, thereby reducing the overall power consumption of each ice machine.

Although the embodiments of the present invention are disclosed above, it is not intended to limit the present invention, and those skilled in the art, regardless of the spirit and scope of the present invention, the shapes, configurations, and features described in the scope of the present application. And the number of modifications may be made, and the scope of patent protection of the present invention shall be determined by the scope of the patent application attached to the specification.

Claims (10)

A flow balance control method is applicable to an ice water system, the ice water system includes a plurality of ice machines and a plurality of primary pumps, wherein the ice machines are respectively connected to the primary pumps, and the primary pumps are respectively located in the ice machines The water return side comprises: adjusting the temperature difference between the water outlet temperature and the return water temperature of the ice machines according to the load rate difference between the load rate of the ice machines and the average load rate of the ice machines a value that increases the temperature difference of the ice machines whose load rate is greater than the average load rate, and the temperature difference of the ice machines whose load rate is less than the average load rate; and according to the temperature differences The values are calculated for the flow rates of the primary pumps, and the flow rates of the primary pumps are adjusted to bring the load rates of the ice machines closer to the average load rate. The flow balance control method according to claim 1, wherein the step of adjusting the temperature difference of each of the ice machines according to the difference between the load rate of the ice machine and the average load rate is further The method includes: when at least one absolute value of the load rate difference of the ice machine is greater than a first threshold, increasing a temperature difference of each of the ice machines whose load rate is greater than the average load rate by a first pre- Setting a value, and reducing each of the temperature differences of the ice machines whose load rate is less than the average load rate by the first preset value; and when the absolute value of the load rate difference of at least one of the ice machines is between When the first threshold value is less than the second threshold value of the first threshold value, the temperature difference between the ice machines with the load rate greater than the average load rate is increased by a second preset value, and Let the load rate be less than the average load rate Each of the temperature differences of the ice machines is reduced by the second predetermined value. The flow balance control method of claim 2, wherein the step of adjusting the temperature difference between the ice machines according to the load rate difference between the load rate of the ice machines and the average load rate is further The method includes: when the absolute value of the load rate difference of the at least one ice machine is between the second threshold value and a third threshold value that is less than the second threshold value, the load rate is greater than the average load rate Each of the temperature differences of the ice machines is increased by a third predetermined value, and each of the temperature differences of the ice machines having a load rate less than the average load rate is decreased by the third preset value. A flow balance control method is applicable to an ice water system, the ice water system includes a plurality of ice machines and a plurality of primary pumps, wherein the ice machines are respectively connected to the primary pumps, and the primary pumps are respectively located in the ice machines The water return side includes: adjusting respective operating frequencies of the primary pumps according to respective load rate differences between the load rate of the ice machines and an average load rate of the ice machines, and each of the primary pumps The operating frequency is proportional to the flow rate provided by the primary pumps, and the operating frequency of the ice pumps corresponding to the ice machines corresponding to the average load rate is reduced, and the increased load rate is less than the average load rate. The ice machine corresponds to the operating frequency of the primary pump so that the load rate of the ice machines approaches the average load rate. The flow balance control method according to claim 4, wherein the step of adjusting each of the operating frequencies of the primary pumps according to the respective load rate differences between the load rate of the ice machines and the average load rate further comprises : when at least one of the ice machines has an absolute value of the load ratio difference greater than a first threshold, the ice machines having a load ratio greater than the average load rate The operating frequency corresponding to the primary pump is decreased by a first preset value, and the operating frequency of the ice pumps corresponding to the primary pump is increased by the first preset value; And when the absolute value of the load rate difference of the at least one ice machine is between the first threshold value and a second threshold value less than the first threshold value, the load rate is greater than the average load rate. The running frequency of the ice pump corresponding to the primary pump is decreased by a second preset value, and the operating frequency of the ice pumps corresponding to the primary pump is increased by the second load rate. default value. The flow balance control method of claim 5, wherein the step of adjusting the respective operating frequencies of the primary pumps according to the respective load rate differences between the load rate of the ice machines and the average load rate further comprises: When the absolute value of the load rate difference of at least one of the ice machines is between the second threshold value and a third threshold value that is less than one of the second threshold values, the load ratio is greater than the average load rate. The running frequency of the ice pump corresponding to the primary pump is decreased by a third preset value, and the operating frequency of the ice pump corresponding to the primary pump is increased by the third pre-load. Set the value. A flow balance control method is applicable to an ice water system, the ice water system includes a plurality of ice machines and a plurality of primary pumps, wherein the ice machines are respectively connected to the primary pumps, and the primary pumps are respectively located in the ice machines The returning water side comprises: respectively adjusting respective operating frequencies of the primary pumps according to the respective flow rates of the primary pumps and the corresponding preset flow rates, and the operating frequencies of the primary pumps are provided by the primary pumps The flow is proportional to the flow, and the reduced flow is greater than the Presetting the running frequency of the primary pumps of the flow rate, and increasing the running frequency of the primary pumps whose flow rate is less than the preset flow rate, so that the load rate of the ice machines approaches an average load of the ice machines rate. The flow balance control method of claim 7, wherein the step of separately adjusting the operating frequencies of the primary pumps according to the respective flows of the primary pumps and the corresponding preset flows further comprises: when at least one of the When the absolute value of the difference between the flow rate of the primary pump and the preset flow rate is greater than a first threshold value, the operating frequency of the primary pumps whose flow rate is greater than the preset flow rate is decreased by a first preset value, and the flow rate is decreased. The operating frequency of the primary pumps less than the preset flow rate increases the first predetermined value; and when the absolute value of the difference between the flow rate of at least one of the primary pumps and the preset flow rate is between the first critical value And when the value is less than the second threshold value, the operating frequency of the primary pumps whose flow rate is greater than the preset flow rate is decreased by a second preset value, and the flow rate is less than the preset flow rate. The operating frequency of the primary pumps is increased by the second predetermined value. The flow balance control method according to claim 8, wherein the step of separately adjusting each of the operating frequencies of the primary pumps according to the respective flow rates of the primary pumps and the corresponding preset flow rates further comprises: when there is at least one When the absolute value of the difference between the flow rate of the primary pump and the preset flow rate is between the second critical value and a third critical value less than the second critical value, the flow rate is greater than the preset flow rate. The operating frequency of the primary pump is decreased by a third predetermined value, and the operating frequency of the primary pumps having a flow less than the predetermined flow rate is increased by the third predetermined value. The flow balance control method of claim 9, wherein the first threshold is 3 percentages, the second threshold is 2 percentages, the first threshold is a percentage, and the first preset value is 1 Hz ( Hz), the second preset value is 0.75 Hertz (Hz) and the third preset value is 0.5 Hertz (Hz).