Integrated high-precision energy efficiency metering device

Abstract

The utility model provides an integrated high-precision energy efficiency metering device. The integrated high-precision energy efficiency metering device comprises a shell, a control chip, a converter, a high-speed integrating circuit, an equipment interface and a control feedback interface, the control chip, the converter and the high-speed integrating circuit are all located in the shell; the equipment interface and the control feedback interface are positioned on the shell; the converter and the high-speed integrating circuit are connected with the sensors and the electricity meters on the cooling side and the freezing side through the equipment interfaces; the control chip is in communication connection with a controller and an upper computer through the control feedback interface; and the control chip is respectively connected with the high-speed integrating circuit and the converter. According to the utility model, the equipment interface is arranged and is connected with the sensors and the electricity meters at the cooling side and the freezing side, so that the energy efficiency metering accuracy of the cold station becomes high; a converter and a high-speed integrating circuit are adopted to calculate the heat dissipating capacity of the cooling side in real time, and heat balance checking of the freezing side and the cooling side can be achieved.

Description

Technical Field

[0001] The utility model relates to the field of energy efficiency measurement, and in particular to an integrated high-precision energy efficiency measurement device. Background Art

[0002] According to relevant statistics, central air conditioning accounts for about 40% to 50% of the total energy consumption of buildings and is the main energy consumer in urban buildings. Central air conditioning systems account for the largest proportion of energy consumption in urban buildings. With the increasing demand for accurate monitoring and efficient control of cooling station energy efficiency, the traditional energy efficiency metering device, which integrates the energy meter on the refrigeration side and the electric meter of the chiller / refrigeration pump / cooling pump / cooling tower to calculate energy efficiency in real time, cannot meet the actual needs well.

[0003] Traditional energy efficiency metering devices only calculate the energy efficiency of the chiller by connecting to the energy meter on the refrigeration side and the equipment meter. The energy meters on the market are usually used for supply and return water temperature differences above 10 to 20°C, and are not suitable for the supply and return water temperature difference range of the cold source system of about 3-6°C. The error is large and cannot meet the error requirement of ±5% of the true value within the measurement range.

[0004] Traditional energy efficiency metering devices only measure the cooling capacity on the refrigeration side, but not the heat capacity on the cooling side. They do not have a thermal balance check and include non-steady-state data such as power on and off or operating mode switching into the calculation, which has a significant impact on the energy efficiency calculation results.

[0005] Traditional energy efficiency metering devices do not take into account the heat dissipation of chillers and water pumps, and there are certain errors in the calculation. They are usually only used for on-site display or transmitting data to the host computer platform, and are not directly connected to the cooling station controller. The energy efficiency metering value cannot be used for actual feedback control and cannot optimize the cooling station automatic control strategy. Utility Model Content

[0006] In order to solve the problem that the traditional energy efficiency metering device only calculates the energy efficiency of the refrigerator by connecting to the refrigeration side energy meter and the equipment meter, resulting in large errors, the utility model proposes an integrated high-precision energy efficiency metering device, including: a housing, a control chip, a converter, a high-speed integration circuit, a device interface and a control feedback interface;

[0007] The control chip, the converter and the high-speed integration circuit are all located inside the housing;

[0008] The device interface and the control feedback interface are located on the housing;

[0009] The converter and the high-speed integration circuit are connected to the sensors and the electric meter on the cooling side and the freezing side through the device interface;

[0010] The control chip is connected to the controller and the host computer through the control feedback interface;

[0011] The control chip is connected to the high-speed integration circuit and the converter respectively. The present application realizes that the data of the cooling side and the freezing side can be collected simultaneously by setting the device interface, and the overall energy efficiency value of the device and the cold station can be calculated in real time; and by setting the control feedback interface, the control command can be received and sent to the cold station machine, water pump and other equipment.

[0012] Optionally, the device interface includes a temperature sensor device interface, a flow sensor device interface and an electric meter interface;

[0013] The number of the temperature sensor device interface, the flow sensor device interface and the electric meter interface are all multiple. The present application can collect different data by setting the temperature sensor device interface, the flow sensor device interface and the electric meter interface to provide data support for accurate analysis.

[0014] Optionally, the sensor includes: a temperature sensor and a flow sensor.

[0015] Optionally, a touch screen interface is also included;

[0016] The touch screen interface is located on the housing;

[0017] The control chip is connected to the touch screen via the touch screen interface. By setting the touch screen interface, the present application can realize an external control device, which is convenient for regulating the device.

[0018] Optionally, it also includes: a reserved interface;

[0019] The reserved interface includes a device interface and / or a control feedback interface. This application meets different working conditions by setting more reserved interfaces.

[0020] Optionally, the controller includes one or more of the following: a cold station chiller controller and a water pump controller.

[0021] Optionally, it further includes: a touch display screen; the touch display screen is mounted on the housing;

[0022] The touch display screen is connected to the control chip.

[0023] Optionally, the touch display screen is in a rectangular structure and is located on the housing;

[0024] The touch display screen includes a touch display module and a fixing plate;

[0025] A groove is provided in the middle of the fixing plate, and the touch display component is embedded in the groove;

[0026] The edge of the fixing plate is adhered to the shell.

[0027] Optionally, the control chip uses SCM620L144MJAO. The control chip is a domestic chip, free from the constraints of foreign chips, and can be upgraded based on the chip.

[0028] Optionally, the housing is a rectangular frame structure, and a device interface and a control feedback interface are respectively arranged on the upper and lower sides of the rectangular frame structure.

[0029] Compared with the prior art, the beneficial effects of the utility model are:

[0030] The utility model provides an integrated high-precision energy efficiency metering device, including: a housing, a control chip, a converter, a high-speed integration circuit, a device interface and a control feedback interface; the control chip, the converter and the high-speed integration circuit are all located inside the housing; the device interface and the control feedback interface are located on the housing; the converter and the high-speed integration circuit are both connected to the sensors and the electric meter on the cooling side and the freezing side through the device interface; the control chip is connected to the controller and the host computer through the control feedback interface; the control chip is connected to the high-speed integration circuit and the converter respectively. The utility model is provided with a device interface, which is connected to the sensors and the electric meter on the cooling side and the freezing side, so that the accuracy of the refrigeration machine efficiency becomes higher; the converter and the high-speed integration circuit are used to calculate the heat dissipation on the cooling side in real time, and the thermal balance check between the freezing side and the cooling side can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of an integrated high-precision energy efficiency metering device with thermal balance verification, correction and control feedback of the utility model;

[0032] Figure 2 This is a design diagram of the built-in control chip of the integrated high-precision energy efficiency metering device of the utility model;

[0033] Figure 3 This is a partial design diagram of the circuit board 16-bit A / D converter and high-speed integration circuit of the integrated high-precision energy efficiency metering device of the utility model;

[0034] Among them, 1-housing, 2-touch display, 3-control chip, 4-temperature sensor, 5-power supply, 6-host computer, 7-smart meter, 8-flow sensor, 9-A / D converter and high-speed integration circuit. DETAILED DESCRIPTION

[0035] The utility model proposes an integrated high-precision energy efficiency metering device with heat balance verification, correction and control feedback. By changing the control chip design, adding a 16-bit A / D converter and a high-speed integration circuit 9, adding interfaces for instrumentation such as a temperature sensor 4, a flow sensor 8, and a touch screen, and reserving a communication interface with controllers such as a cooling station chiller and a water pump, the following functions can be realized:

[0036] First, data from the cooling and freezing sides can be collected simultaneously to calculate the overall energy efficiency of the equipment and the cold station in real time;

[0037] Second, the overall high-precision energy efficiency measurement of the cold station is automatically corrected;

[0038] Third, the thermal balance check between the freezing side and the cooling side can be realized;

[0039] Fourth, it can push energy efficiency calculation values ​​in real time and participate in the feedback control of refrigeration plants, water pumps and other equipment.

[0040] Embodiment 1:

[0041] An integrated high-precision energy efficiency metering device, such as Figure 1 As shown: including: housing 1, control chip 3, converter, high-speed integration circuit, device interface and control feedback interface;

[0042] The control chip 3, the converter and the high-speed integration circuit are all located inside the housing 1;

[0043] The device interface and control feedback interface are located on the housing 1;

[0044] The converter and the high-speed integration circuit are connected to the sensors and the electric meter on the cooling side and the freezing side through the device interface;

[0045] The control chip 3 is connected to the controller and the host computer 6 through the control feedback interface;

[0046] The control chip 3 is connected to the high-speed integration circuit and the converter respectively.

[0047] An integrated high-precision energy efficiency metering device aims to integrate the overall accurate energy efficiency measurement and correction function of the central air-conditioning cold source system, the heat balance verification function of the refrigeration side and the cooling side, and the control feedback of equipment such as chillers, water pumps, and cooling towers, so as to achieve more accurate energy efficiency control of the central air-conditioning cold source system.

[0048] First, an integrated high-precision energy efficiency metering device with thermal balance verification, correction and control feedback can realize the simultaneous multi-channel data collection of the cooling side and the freezing side of the cold source system of the chiller by setting the equipment interface, and calculate the overall energy efficiency value and thermal balance rate of the equipment and the cold station in real time.

[0049] In general energy efficiency systems, the cold data collection on the freezing side and the cooling side is to collect the cold data and the electricity data separately for energy efficiency calculation, or to calculate through the host computer 6. This device adds a device interface to connect the temperature sensor 4 and the flow sensor 8 on the freezing side and the cooling side, and integrates the data of the cooling side and the freezing side into the same A / D converter and high-speed integration circuit 9 of the control chip 3. By adjusting the timing of the control chip 3, simultaneous multi-channel collection and calculation are realized, and the overall energy efficiency value of the equipment and the cold station can be calculated in real time and deviation correction can be performed, with strong data consistency.

[0050] Second, an integrated high-precision energy efficiency metering device, which pairs and selects high-precision temperature sensor 4, flow sensor 8, electric meter, built-in control chip 3, uses 16-bit A / D converter and high-speed integration circuit 9, and meets the high-precision measurement requirements of the overall energy efficiency within the range of 3-6°C supply and return water temperature difference of the cold source system of the chiller, and the total error is not higher than 1.85%.

[0051] The central water-cooled cold source system is generally composed of a refrigeration host, a chilled water pump, a cooling water pump, a cooling tower, pipeline valves, etc. The system energy efficiency is defined as the ratio of the total power consumption of the equipment in the computer room to the total cooling capacity. The specific calculation formula is as follows:

[0052]

[0053] The efficiency of the central water-cooled cold source system is a comprehensive indicator for evaluating whether the entire refrigeration room is energy-efficient, and the average energy efficiency throughout the year (a complete cooling season) is usually used to determine whether it is truly efficient. For example, according to the standards proposed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), refrigeration rooms with an annual comprehensive energy efficiency below 0.75kW / RT are high-efficiency rooms, and those with a comprehensive energy efficiency above 1.0kW / RT are rooms that need to be renovated.

[0054] Accurate energy efficiency monitoring device configuration:

[0055]

[0056]

[0057] %power: Power meter error: generally 1.0%;

[0058] %flow: flow meter error: generally 1.0%;

[0059] %ΔT: Temperature difference error.

[0060] The accuracy of the precise system temperature is ±0.03°C. Taking the normal temperature difference range ΔT = 5°C, ΔT = 0.03*2 / 5 = 1.2%.

[0061] Third, the original energy efficiency metering device only has energy efficiency metering on the refrigeration side. The energy efficiency of the refrigeration side is calculated by collecting the cold meter and smart meter 7 on the refrigeration side, and no data from the cooling side is involved in the calculation, and there is no thermal balance rate verification. An integrated high-precision energy efficiency metering device with thermal balance verification, correction and control feedback is based on this, and an interface is added to connect to the high-precision temperature sensor 4 and flow sensor 8 on the cooling side, and the same A / D converter integrated into the control chip 3 adjusts the control timing of the control chip 3. A 16-bit A / D converter and a high-speed integration circuit 9 are used to calculate the heat dissipation on the cooling side in real time, which can realize the thermal balance verification of the refrigeration side and the cooling side and the precise energy efficiency measurement of the entire cold source system.

[0062] In order to ensure the credibility of energy efficiency data, it is also necessary to verify the thermal balance of the refrigeration room, that is, according to the first law of thermodynamics and the principle of refrigeration cycle, the heat dissipated by the refrigerant in the condenser should be equal to the heat absorbed by the evaporator + the work done by the refrigeration compressor. For example: According to the AHRI550 / 590 standard requirements, during the normal working time of the entire cold source system, more than 80% of the data points within the audit period must meet the thermal balance calculated within ±5%, and the energy efficiency value is considered credible.

[0063] However, due to the two-phase flow inside the refrigerant, the actual cold source system energy efficiency monitoring device cannot monitor the heat dissipation of the refrigerant, the heat absorption of the evaporator and the power of the chiller to make a thermal balance. Currently, the thermal balance is verified by monitoring the cooling capacity of the chilled water, the heat dissipation of the cooling water and the electrical power of the chiller. That is:

[0064] A=q 冷冻供冷量 =ρ×F chw ×C p ×(T chwr -T chws );

[0065] Among them, q 冷冻供冷量 is the cooling capacity of chilled water in kW; ρ is the density of chilled water in kg / m 3 ; F chw is the water flow rate on the chilled side m 3 / s;C p is the specific heat capacity of chilled water kJ / kg℃; T chwr is the chilled water return temperature ℃; T chws is the chilled water return temperature ℃;

[0066] B=q 冷却散热量 =ρ×F cw ×C p ×(T cwr -T cws );

[0067] Among them, q 冷却散热量is the heat dissipation of cooling water kW; ρ is the cooling water density kg / m 3 ; F cw is the water flow rate on the cooling side m 3 / s;C p is the specific heat capacity of cooling water kJ / kg℃; T cwr is the cooling return water temperature ℃; T cws is the cooling water supply temperature ℃;

[0068] C=W 冷机电功率 =KW ch-1 +KW ch-2 +KW ch-3 ;

[0069] Among them, W 冷机电功率 Is the electrical power of the cooling machine; KW ch-1 The electrical power of No. 1 cooling machine; KW ch-2 The electrical power of No. 2 cooling machine; KW ch-3 It is the electrical power of No. 3 cold machine.

[0070] Heat balance calculation = [(A+C)-B] / B×100%;

[0071] Among them, A is the cooling capacity of chilled water, B is the heat dissipation of cooling water, and C is the electrical power of the chiller.

[0072] Fourth, an integrated high-precision energy efficiency metering device with thermal balance verification, correction and control feedback adds a touch screen, has touch display and input functions, allows different projects to input different efficiencies of chillers, water pumps, etc., has a built-in correction formula, and the basic equipment parameters of different projects can be input through the touch screen, and the energy efficiency algorithm can be automatically corrected through the correction formula.

[0073] The touch display screen is integrated on the housing and connected to the control chip. The touch display screen is a rectangular structure, including a touch display module and a fixing plate;

[0074] A groove is provided in the middle of the fixing plate, and the touch display component is embedded in the groove;

[0075] The edges of the fixing plate are glued to the housing.

[0076] The housing is a rectangular shell, and the upper and lower sides of the rectangular frame structure are respectively provided with a device interface and a control feedback interface. The upper half of the housing is provided with a touch display screen, the top of the touch display screen is provided with a device control feedback interface, and the bottom of the lower half of the housing is provided with a device interface.

[0077] Since the motor power of compressors, refrigeration pumps, cooling pumps, etc. is not 100% converted into effective work, there is heat dissipation, and the pump itself also has hydraulic, mechanical and impeller volume losses. There are errors in the calculation of heat balance verification using the above-mentioned chilled water cooling capacity, cooling water heat dissipation and chiller electrical power. This device proposes a correction method, which adds a screen to the energy efficiency monitoring device with input function. Engineers can input basic equipment parameters of different projects through the touch screen and introduce these parameters into the built-in heat balance calculation of the control chip 3. The details are as follows:

[0078] Open water chiller correction value input: Considering that the open water chiller motor has heat dissipation, and its heat is discharged into the machine room environment through heat dissipation rather than converted into cooling side heat dissipation, this energy efficiency monitoring device provides an input interface for the motor efficiency η of each open water chiller. An integrated high-precision energy efficiency metering device with thermal balance verification, correction and control feedback automatically corrects the value of the open chiller in the thermal balance verification based on the built-in formula model of the control chip 3 and the input parameters such as the open chiller motor efficiency:

[0079] W 开式冷机电功率修正 =KW ch ×η ch ;

[0080] Among them, W 开式冷机电功率修正 Corrected electric power for open-type cooler kW; KW ch is the electrical power of the open-type refrigerator in kW; η ch is the motor efficiency of the open-type cooler.

[0081] The closed cooler has a built-in motor, and its heat dissipation is converted into heat and uniformly dissipated from the cooling side, so no correction is required.

[0082] Chilled water pump correction value input: Considering the heat dissipation of the chilled water pump motor and the pump's own efficiency, the heat dissipated is discharged into the machine room environment through heat dissipation, and the pump efficiency loss enters the system in the form of heat, which needs to be dissipated on the cooling side just like the work done by the chiller. Therefore, this device provides the chilled water pump motor efficiency η chm , pump rated efficiency η chp The device automatically corrects the cooling capacity of the refrigeration side in the heat balance according to the built-in formula model of the control chip 3 and the input parameters such as the efficiency of the chilled water pump motor and the rated efficiency of the chilled water pump:

[0083] C 修正 =W 冷机电功率 +KW chp ×η chm ×(1-η chp );

[0084] Among them, C 修正 W is the correction value of the chilled water pump;冷机电功率 kW is the electrical power of the cooling machine; chp is the chilled water pump power kW; η chm is the chilled water pump motor efficiency; η chp is the chilled water pump efficiency.

[0085] Cooling water pump correction value input: Consider the heat dissipation of the cooling water pump motor and the pump's own efficiency. The heat dissipated is discharged into the computer room environment through heat dissipation, while the pump efficiency loss enters the cooling water in the form of heat, which increases the heat dissipation on the cooling side to a certain extent.

[0086] Therefore, the energy efficiency monitoring device provides the cooling water pump motor efficiency η cm , pump rated efficiency η cp The device automatically corrects the cooling side heat dissipation in the thermal balance according to the built-in formula model of the control chip 3 and the input parameters such as the cooling water pump motor efficiency and the cooling water pump rated efficiency:

[0087] B 修正 =ρ×F cw ×C p ×(T cwr -T cws )-KW cp ×η cm ×(1-η cp );

[0088] Among them, B 修正 is the corrected cooling side heat dissipation kW; ρ is the cooling water density kg / m 3 ; F cw is the cooling water flow rate m 3 / s; cooling water specific heat capacity kJ / kg℃; Tcwr is cooling return water temperature℃; Tcws is cooling supply water temperature℃; KW cp is the cooling water pump power kW; η cm is the cooling water pump motor efficiency; η cp It is the efficiency of cooling water pump body.

[0089] The correction coefficients of chillers and water pumps in different projects are different. By adding input functions, users are allowed to input them on-site according to actual conditions without having to change them through complex background programs, which provides great convenience and improves the accuracy of energy efficiency calculations.

[0090] Fifth, an integrated high-precision energy efficiency metering device with heat balance verification, correction and control feedback, with an additional communication interface with controllers such as cooling station chillers, water pumps, cooling tower fans, etc., can push energy efficiency calculation values ​​in real time to chillers, water pumps, cooling tower controllers, and participate in PID control of chillers, water pumps, cooling tower fans, etc. That is, according to the real-time energy efficiency calculation value, the operation of chillers, water pumps, and cooling tower fans is optimized and controlled, so that they are always in the high-efficiency (i.e., the energy efficiency of the cooling station and equipment, calculated by this device) operating range.

[0091] like Figure 1 As shown, an integrated high-precision energy efficiency metering device 1, referred to as a high-precision energy efficiency metering device 1, a power supply 5, a built-in control chip 3 (see the circuit diagram for details) Figure 2 ), 16-bit A / D converter and high-speed integration circuit 9 (see the circuit diagram for details) Figure 3 ), connected to the touch display screen 2, automatically calculates and corrects through the built-in energy efficiency, thermal balance, energy efficiency correction and other algorithm models of the control chip 3; the control chip 3 here is connected to the 16-bit A / D converter and the high-speed integration circuit 9 through the SPI bus.

[0092] The high-precision energy efficiency metering device 1 integrates and collects data of up to 8 sets of temperature sensors 4 and up to 4 sets of flow sensors 8 on the main pipes and main branches of the refrigeration and cooling sides, and collects data of multiple smart meters 7;

[0093] The high-precision energy efficiency metering device 1 is based on the collected data such as temperature, flow, electric meter, equipment parameters, etc., through the new control chip 3 design and A / D converter and high-speed integration circuit 9, and is equipped with temperature sensor 4 and flow sensor 8 interfaces and control feedback interfaces of equipment such as chillers and water pumps (reserved interfaces x5), a touch screen 2, and corresponding built-in overall energy efficiency metering algorithms, correction algorithms and thermal balance rate algorithm models to perform calculations such as cooling capacity, energy efficiency and thermal balance verification;

[0094] The instrument integrated in the high-precision energy efficiency metering device 1 can increase the data collection on the cooling side, calculate the energy efficiency on the cooling side, and monitor the balance rate between the freezing side and the cooling side; in addition, it increases the communication with the controllers of the cold station chiller, water pump, cooling tower fan, etc., and reserves 5 groups of modbus protocol interfaces, which can participate in the feedback control of the cold station chiller, water pump, cooling tower fan and other equipment, and efficiently control the above equipment and the overall cold source system according to the real-time energy efficiency calculation data of the high-precision energy efficiency metering device 1. The high-precision energy efficiency metering device 1 communicates with the host computer 6, and can report the equipment operation status, data collection status, energy efficiency calculation and balance rate calculation status. At the same time, the host computer 6 can send parameters for data correction and control feedback.

[0095] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. An integrated high-precision energy efficiency metering device, characterized in that: include: Housing, control chip, converter, high-speed integration circuit, device interface and control feedback interface; The control chip, the converter and the high-speed integration circuit are all located inside the housing; The device interface and the control feedback interface are located on the housing; The converter and the high-speed integration circuit are connected to the sensors and the electric meter on the cooling side and the freezing side through the device interface; The control chip is connected to the controller and the host computer through the control feedback interface; The control chip is connected to the high-speed integration circuit and the converter respectively; The device interface includes a temperature sensor device interface, a flow sensor device interface and an electric meter interface; The number of the temperature sensor device interface, the flow sensor device interface and the electric meter interface are all multiple; The sensors include: a temperature sensor and a flow sensor; The temperature sensor is connected to the temperature sensor device interface; The flow sensor is connected to the flow sensor device interface; Also includes a touch screen interface; The touch screen interface is located on the housing; The control chip is connected to the touch screen via the touch screen interface; The control chip adopts SCM620L144MJAO.

2. The device according to claim 1, characterized in that Also includes: reserved interface; The reserved interface includes a device interface and / or a control feedback interface.

3. The device according to claim 1, characterized in that The controller includes one or more of the following: a refrigeration station chiller controller and a water pump controller.

4. The device according to claim 1, characterized in that Also includes: A touch display screen; the touch display screen is integrated on the housing; The touch display screen is connected to the control chip.

5. The device according to claim 4, characterized in that The touch display screen is in a rectangular structure and is located on the housing.

6. The device according to claim 5, characterized in that The touch display screen includes a touch display module and a fixing plate; A groove is provided in the middle of the fixing plate, and the touch display module is embedded in the groove; The edge of the fixing plate is adhered to the shell.

7. The device according to claim 1, characterized in that The housing is a rectangular shell, and the upper and lower sides of the rectangular shell are respectively provided with a device interface and a control feedback interface.

Images