A water source heat pump outlet water temperature optimization control method for waste heat recovery

Abstract

The present application relates to a kind of water source heat pump outlet temperature optimization control method for waste heat recovery, by fitting outlet temperature and heat pump operation COP data, the functional relationship of both is obtained, while calculating outlet temperature T system output heat is Q, respectively, the waste heat replacement income F1 and the waste heat replacement income F1 of calculating heat pump operation cost F2 are constructed, the maximum income model including waste heat replacement income F1 and heat pump operation cost F2 is constructed, the optimal temperature Tbest of the maximum income Fmax and heat pump outlet temperature is obtained by particle swarm optimization algorithm calculation generation.The present application constructs the optimization control model considering the maximum income of heat pump waste heat utilization system from the angle of heat pump operation optimization control, the problem of heat pump outlet temperature optimization control.

Description

Technical Field

[0001] This invention belongs to the field of integrated energy technology, and in particular to a method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery. Background Technology

[0002] With the development of heat pump technology, more and more heat pump products can reduce the temperature of low-temperature industrial waste heat (25-35°C) to 60-120°C, providing a new approach for energy conservation and carbon reduction in the industrial sector. In waste heat recovery scenarios, if the heat pump outlet water temperature is too high, the heat pump COP will decrease; if the heat pump outlet water temperature is too low, the waste heat utilization will be too low. Therefore, how to set the outlet water temperature of the water source heat pump has become a problem that needs to be solved to optimize the operation of the waste heat recovery system. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and propose an optimized control method for the outlet water temperature of a water source heat pump for waste heat recovery. This method comprehensively considers equipment operating efficiency and waste heat utilization, with the goal of maximizing the benefits of the waste heat recovery system, and effectively solves the problem of heat pump outlet water temperature control.

[0004] The technical problem solved by this invention is achieved through the following technical solution:

[0005] A method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery includes the following steps:

[0006] Step 1: Adjust the actual outlet water temperature of the heat pump within the heat pump outlet water temperature range and obtain the heat pump operating COP data;

[0007] Step 2: Use the least squares method to fit the outlet water temperature and heat pump operation COP data to obtain the functional relationship fcop(T) between heat pump operation COP and outlet water temperature T;

[0008] Step 3: Calculate the system output heat Q when the outlet water temperature is T;

[0009] Step 4: Calculate the waste heat replacement benefit F1 based on the system output heat Q at the outlet water temperature T;

[0010] Step 5: Calculate the heat pump operating cost F2 based on the system output heat Q at the outlet water temperature T;

[0011] Step 6: Establish a maximum benefit model for optimizing the control of heat pump outlet water temperature: F=max(F1-F2);

[0012] Step 7: Using the change rules of the particle swarm optimization algorithm, the optimal temperature Tbest that maximizes the profit Fmax and the heat pump outlet water temperature is generated through continuous iteration.

[0013] Moreover, the specific implementation method of step 3 is as follows: Q = (T - Tin) * water flow rate * water specific heat capacity, where Tin is the heat pump inlet water temperature.

[0014] Moreover, the specific implementation method of step 4 is: F1 = Q / calorific value of natural gas * price of natural gas.

[0015] Moreover, the specific implementation method of step 5 is: F2 = Q / fcop(T) * electricity price.

[0016] Moreover, the specific implementation method of step 6 is: F = max(F1 - F2).

[0017] The advantages and positive effects of this invention are:

[0018] This invention fits the outlet water temperature and the COP (Coefficient of Performance) data of the heat pump to obtain their functional relationship. Simultaneously, it calculates the system output heat Q at outlet water temperature T. It then constructs models to calculate the waste heat replacement benefit F1 and the heat pump operating cost F2, and builds a profit-maximizing model that includes both F1 and F2. The optimal temperature Tbest, which generates the maximum profit Fmax and the heat pump outlet water temperature, is calculated using a particle swarm optimization algorithm. This invention, from the perspective of heat pump operation optimization control, constructs an optimization control model that considers maximizing the system's profit from heat pump waste heat utilization, addressing the problem of optimizing the heat pump outlet water temperature. Detailed Implementation

[0019] The present invention will now be described in further detail.

[0020] A method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery includes the following steps:

[0021] Step 1: Adjust the actual outlet water temperature of the heat pump within the heat pump outlet water temperature range and obtain the heat pump operating COP data.

[0022] Step 2: Use the least squares method to fit the outlet water temperature and heat pump operation COP data to obtain the functional relationship fcop(T) between heat pump operation COP and outlet water temperature T.

[0023] Step 3: Calculate the system output heat Q when the outlet water temperature is T.

[0024] Q = (T - Tin) * water flow rate * water specific heat capacity, where Tin is the heat pump inlet water temperature.

[0025] Step 4: Calculate the waste heat substitution benefit F1 based on the system output heat Q at the outlet water temperature T.

[0026] F1 = Q / Calorific value of natural gas * Price of natural gas

[0027] Step 5: Calculate the heat pump operating cost F2 based on the system output heat Q at the outlet water temperature T.

[0028] F2 = Q / fcop(T) * electricity price.

[0029] Step 6: Establish a profit-maximizing model for optimizing the control of heat pump outlet water temperature: F=max(F1-F2).

[0030] F = max(F1 - F2).

[0031] Step 7: Using the change rules of the particle swarm optimization algorithm, the optimal temperature Tbest that maximizes the profit Fmax and the heat pump outlet water temperature is generated through continuous iteration.

[0032] Step 8: When the water flow rate of the waste heat recovery system or the inlet water temperature of the heat pump changes, repeat the calculation process in step 7 to adjust the outlet water temperature of the heat pump to the optimal temperature.

[0033] It should be emphasized that the embodiments described in this invention are illustrative rather than limiting. Therefore, this invention includes, but is not limited to, the embodiments described in the specific implementation. Any other implementations derived by those skilled in the art based on the technical solutions of this invention are also within the scope of protection of this invention.

Claims

1. A method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery, characterized in that: Includes the following steps: Step 1: Adjust the actual outlet water temperature of the heat pump within the heat pump outlet water temperature range and obtain the heat pump operating COP data; Step 2: Use the least squares method to fit the outlet water temperature and heat pump operation COP data to obtain the functional relationship fcop(T) between heat pump operation COP and outlet water temperature T; Step 3: Calculate the system output heat Q when the outlet water temperature is T; Step 4: Calculate the waste heat replacement benefit F1 based on the system output heat Q at the outlet water temperature T; Step 5: Calculate the heat pump operating cost F2 based on the system output heat Q at the outlet water temperature T; Step 6: Establish a maximum benefit model for optimizing the control of heat pump outlet water temperature: F=max(F1-F2); Step 7: Using the change rules of the particle swarm optimization algorithm, the optimal temperature Tbest that maximizes the profit Fmax and the heat pump outlet water temperature is generated through continuous iteration.

2. The method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery according to claim 1, characterized in that: The specific implementation method of step 3 is as follows: Q = (T - Tin) * water flow rate * water specific heat capacity, where Tin is the heat pump inlet water temperature.

3. The method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery according to claim 1, characterized in that: The specific implementation method of step 4 is: F1 = Q / calorific value of natural gas * price of natural gas.

4. The method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery according to claim 1, characterized in that: The specific implementation method of step 5 is: F2 = Q / fcop(T) * electricity price.

5. The method for optimizing and controlling the outlet water temperature of a water source heat pump for waste heat recovery according to claim 1, characterized in that: The specific implementation method of step 6 is: F = max(F1 - F2).