JP5276310B2 - Pump power calculation apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To calculate, based on a pump characteristic value indicating an arbitrary operation point, a shaft power and power consumption required when operating the pump at the operation point. <P>SOLUTION: A reference flow rate calculation section 16A calculates a reference flow rate Q<SB>0</SB>at a reference operation point R<SB>0</SB>based on an input characteristic value 2 acquired by a data acquisition section 11. A reference shaft power calculation section 16B calculates a reference shaft power E<SB>0</SB>of the pump at a reference power point P<SB>0</SB>based on the reference flow rate Q<SB>0</SB>calculated by the reference flow rate calculation section 16A. A power calculation section 16C specifies a shaft power curve at control B<SB>1</SB>based on the reference flow rate Q<SB>0</SB>calculated by the reference flow rate calculation section 16A, the reference shaft power E<SB>0</SB>calculated by the reference shaft power calculation section 16B and an at-control shaft power curve function expression of a storage section 15, so as to calculate a shaft power at control E<SB>1</SB>at a power point at control P<SB>1</SB>as a pump power value 3 from a flow rate at control Q<SB>1</SB>and a shaft power curve at control B<SB>1</SB>. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a pump control technique, and more particularly to a technique for calculating a pump power value indicating an operation characteristic of a pump.

  In a pump system of a general air conditioning equipment provided in an office building, a public facility, a hotel, etc., an inverter is provided in a pump (secondary pump) that feeds heat source water to variably control the pump rotation speed. As a result, the pump can be controlled so that the heat source water is fed by a necessary flow rate on the load side, and power consumption in the pump can be reduced.

In such a pump system, characteristic values indicating the operation state of the pump, such as a flow rate, a head, a shaft power, and a pump rotation speed ratio, which are necessary for the operation control of the pump, are represented by a flow meter, a pressure gauge, a power meter, and a rotation speed counter Based on the measurement results, other pump characteristic values that are not measured are calculated using pump operating characteristics such as a lift curve, a shaft power curve, and a resistance curve.
As a specific example of the past, based on the pump rotation speed and pump power consumption, the flow rate and head during pump rotation speed control are calculated based on the lift curve function data, shaft power curve function data, and resistance curve data corresponding to the rotation speed. There is something to be calculated (for example, see Patent Document 1).

JP 2006-307682 A

  In the pump system, from the viewpoint of energy saving, the pump operating point and control algorithm may be changed to examine reduction of shaft power and power consumption required for the pump. In such a case, it is necessary to grasp how the shaft power and the power consumption change based on pump characteristic values such as a flow rate, a head, or a rotational speed indicating a new operating point.

However, in such a conventional technique, the flow rate and the head are calculated and used for control as the pump characteristic value, and the shaft of the pump is based on the pump characteristic value such as the flow rate, the head, or the rotational speed indicating an arbitrary operating point. Power and power consumption could not be calculated.
The present invention is for solving such problems, and based on a pump characteristic value indicating an arbitrary operating point, calculating shaft power and power consumption required when the pump is operated at the operating point. It aims at providing the pump power calculation device which can do.

In order to achieve such an object, the pump power calculation apparatus according to the present invention has two characteristics that indicate the operation status of a pump whose rotation speed N is variably controlled at an arbitrary control rotation speed N _1. A pump power calculation device for calculating a pump power value indicating the power required for the pump in the operating situation from a value, and a reference head curve showing a relationship between a flow rate and a head related to the pump at a predetermined reference rotational speed N ₀ A ₀ , the reference shaft power curve B ₀ showing the relationship between the flow rate and shaft power related to the pump at the reference rotational speed N ₀ , and the pump when the rotational speed N of the pump is controlled while the pump piping resistance is constant Shows the relationship between the flow rate of the pump and the shaft power when the rotational speed N of the pump is controlled while the piping resistance of the pump is constant. A storage unit for storing a control time axis power curve function shape formula approximating the control time axis power curve B ₁ , a pump motor efficiency η _m and an inverter efficiency η _i, and operating at the control speed N ₁ A data acquisition unit that acquires a control flow rate Q ₁ and a control lift H ₁ that indicate the characteristics of the pump as the input characteristic value, and a control operation point that is specified by the input characteristic value acquired by the data acquisition unit Based on R ₁ , the resistance curve C is identified by calculating a constant of the resistance curve function shape formula of the storage unit, and from the intersection of the resistance curve C and the reference head curve A ₀ of the storage unit by identifying the reference operating point R ₀ comprising, a reference flow rate calculation unit that calculates a reference flow rate Q ₀ in the reference operating point R _0, wherein the reference flow rate Q ₀ and the memory unit in the reference operating point R ₀ reference axis power curve B ₀ and the group There, by specifying the reference power point P ₀ at the time of operating the pump at the reference rotational speed N _0, and the reference axis power calculation unit for calculating a reference axis power E ₀ in the reference power point P _0, the reference Based on the reference flow rate Q ₀ and the reference shaft power E _{0 at the} power point P _0, the control time axis of the storage unit is calculated by calculating a constant of the control time axis power curve function shape formula of the storage unit. The power curve B ₁ is specified, and the control time when the pump is operated at the control rotation speed N ₁ from the control time power curve B ₁ and the control flow rate Q ₁ acquired by the data acquisition unit. The power for calculating the shaft power E ₁ and calculating the control power consumption W ₁ of the pump as the pump power value from the control-time shaft power E ₁ , the motor efficiency η _{m of the} storage unit and the inverter efficiency η _i And a calculation unit.

  The storage unit stores the pump motor efficiency and the inverter efficiency, and the power calculation unit calculates the pump power consumption as the pump power value from the control time axis power and the storage unit motor efficiency and the inverter efficiency. May be.

Further, the pump power calculation method according to the present invention is based on two characteristic values indicating the operation status of the pump for the pump in which the rotation speed N is variably controlled at an arbitrary control rotation speed N _1. A pump power calculation method used in a pump power calculation device for calculating a pump power value indicating power required in the storage, wherein a storage unit shows a relationship between a flow rate and a head related to the pump at a predetermined reference rotational speed N _0. The reference lift curve A ₀ , the reference shaft power curve B ₀ indicating the relationship between the flow rate and shaft power related to the pump at the reference rotation speed N ₀ , and the pump rotation speed N were controlled with the pump piping resistance being constant. The resistance curve function shape formula approximating the resistance curve C indicating the relationship between the pump flow rate and the head at the time, and the pump flow rate and shaft when the pump rotational speed N is controlled with the pump piping resistance constant A storage step for storing a control time axis power curve function shape formula approximating a control time axis power curve B ₁ indicating a power relationship, a pump motor efficiency η _m and an inverter efficiency η _i , and a data acquisition unit, A data acquisition step for acquiring a control flow rate Q ₁ and a control lift H ₁ indicating the characteristics of the pump operating at the control rotation speed N ₁ as the input characteristic values, and a reference flow rate calculation unit in the data acquisition step The resistance curve C is specified by calculating a constant of the resistance curve function shape formula of the storage unit based on the control operating point R ₁ specified by the acquired input characteristic value, and the resistance curve C by identifying the reference operating point R ₀ consisting of the intersection between the reference head curve a ₀ of the storage unit and the reference flow rate calculation step of calculating a reference flow rate Q ₀ in the reference operating point R _0, the reference axis power Out portion, on the basis of said reference flow rate Q ₀ and the reference axis power curve B ₀ of the memory unit in the reference operating point R _0, the reference power point P at the time of operating the pump at the reference rotational speed N ₀ by identifying _0, the reference axis power calculating step of calculating a reference axis power E ₀ in the reference power point P _0, the power calculating portion, the reference flow rate Q ₀ and the reference axis in said reference power point P ₀ Based on the power E ₀ , the control time axis power curve B ₁ of the storage unit is specified by calculating a constant of the control time axis power curve function shape formula of the storage unit , and this control time axis power curve from B ₁ and the time has been the control of acquired in the data acquisition step flow Q ₁ Tokyo, calculates the control time shaft power E ₁ at the time of operating the pump at the control time of the rotational speed N _1, the control time of shaft power E ₁ and the motor efficiency η _{m of the} storage unit and the And a power calculation step of calculating the pump control power consumption W ₁ as the pump power value from the inverter efficiency η _i .

According to the present invention, on the basis of a control flow rate and a control head indicating an arbitrary operating point, the control time axis power required when the pump is operated at that operating point, and further the power consumption is calculated as the pump power value. be able to.
For this reason, the pump operating point and control algorithm are changed from the viewpoint of energy saving by comparing the pump power value corresponding to each operating point based on the control flow rate and control head at different operating points, and the pump Therefore, it is possible to very easily study the reduction of the shaft power and power consumption required for the above.

Next, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, with reference to FIG. 1, a pump power calculation apparatus according to a first embodiment of the present invention will be described. FIG. 1 is a block diagram showing a configuration of a pump power calculation apparatus according to the first embodiment of the present invention.

  The pump power calculation device 1 is composed of an information calculation processing device that performs calculation processing using a computer such as a workstation or a personal computer as a whole, and a pump whose rotation speed is variably controlled at an arbitrary control rotation speed in the pump system 5. Among the plurality of characteristic values indicating the operation status of the pump, a function of calculating an unknown characteristic value as the pump power value 3 from the input known input characteristic value 2 is provided.

  The pump power calculation device 1 includes a data acquisition unit 11, an operation input unit 12, a screen display unit 13, a data output unit 14, a storage unit 15, and an arithmetic processing unit 16 as main functional units. The arithmetic processing unit 16 is provided with a reference flow rate calculation unit 16A, a reference shaft power calculation unit 16B, and a power calculation unit 16C as processing units that perform pump power calculation processing.

  In the present embodiment, the flow rate of the pump when the rotational speed of the pump is controlled by the reference flow rate calculation unit 16A based on the input characteristic value 2 acquired by the data acquisition unit 11 while the pump piping resistance is constant. A reference flow rate at a reference operating point consisting of an intersection of a resistance curve indicating a lift relationship and a reference lift curve in the storage unit 15 is calculated, and the reference flow rate calculated by the reference flow rate calculation unit 16A is calculated by the reference shaft power calculation unit 16B. Based on the intersection of the control time axis power curve indicating the relationship between the pump flow rate and the shaft power when the pump rotation speed is controlled with the pump piping resistance being constant, and the reference shaft power curve of the storage unit 15. The reference shaft power of the pump at the reference power point is calculated, and the reference flow rate calculated by the reference flow rate calculation unit 16A and the reference shaft power calculated by the reference shaft power calculation unit 16B are calculated by the power calculation unit 16C. A control time axis power curve is specified on the basis of the control time axis power curve function shape formula of the memory unit 15, and the control time axis power at the control time power point is determined from the control flow rate and the control time axis power curve by the pump power value 3 Calculate as

[Pump system]
Next, with reference to FIG. 2, a pump system to be processed by the pump power calculation apparatus according to the first embodiment of the present invention will be described. FIG. 2 is a block diagram illustrating a configuration example of a pump system to be processed by the pump power calculation device.
The pump system 5 is a pump system for general air conditioning equipment provided in office buildings, public facilities, hotels, etc., has two heat sources, has a primary pump as a heat source machine, and is used as a forward header. Secondary pumps are provided, and inverters are provided in these pumps to variably control the pump rotation speed. Note that the present invention is not limited to a pump system having two heat sources, and can be similarly applied to a pump system having one system or three or more heat sources, and similar operational effects can be obtained.

  The pump system 5 includes, as main devices, a control device 50A, a secondary pump control device 50B, heat source devices 51A and 51B, primary pumps 52A and 52B, forward headers 53A and 53B, and secondary pumps 54A, 54B and 54C. A differential pressure gauge 55, a valve 56, a forward water temperature sensor 57A, a return water temperature sensor 57B, a flow meter 58, and a return header 59 are provided.

The return header 59 and the forward header 53A are connected by two parallel heat source pipes 61, 62. The heat source pipes 61, 62 are connected to the heat source machine 51A, the primary pump 52A, the heat source machine 51B, and Primary pumps 52B are arranged in series, respectively. The bypass pipeline 60 is a pipeline connecting the return header 59 and the forward header 53A with a bypass pathway.
The heat source water returned from the external load 65 is distributed to the heat source pipes 61 and 62 by the return header 59 and adjusted to an appropriate temperature by the heat source devices 51A and 51B according to the control from the control device 50A, and then the primary pump. By 52A and 52B, the liquid is sent to the forward header 53A at a flow rate corresponding to the inverter control from the control device 50A.

Secondary pumps 54A, 54B, 54C, differential pressure gauge 55, and valve 56 are connected in parallel between forward headers 53A, 53B.
The heat source water sent from the primary pumps 52A and 52B through the forward header 53A is passed through the forward header 53B by the secondary pumps 54A, 54B and 54C at a flow rate corresponding to the inverter control from the secondary pump control device 50B. To the external load 65 side. The pressure difference between the forward headers 53A and 53B, that is, the head H is measured by the differential pressure gauge 55 and output to the secondary pump control device 50B.

  The external load 65 includes a heat exchanger such as an air conditioner and a valve that adjusts the amount of heat source water supplied to the heat exchanger, and serves as a pipe resistance for the secondary pumps 54A, 54B, and 54C. The heat source water sent from the forward header 53B is supplied to the external load 65 via the forward water pipe 63, and after heat exchange with the external load 65, returns to the return header 59 via the return water pipe 64. The outgoing water pipe 63 is provided with an outgoing water temperature sensor 57A, and the temperature of the heat source water supplied to the external load 65, that is, the temperature of the outgoing water is measured and output to the control device 50A. A return water temperature sensor 57B is provided in the return water pipe 64, and the temperature of the heat source water returning from the external load 65, that is, the return water is measured and output to the control device 50A. The return water pipe 64 is provided with a flow meter 58, and the flow rate Q of the heat source water circulating through the external load 65 is measured and output to the control device 50A and the secondary pump control device 50B.

The control device 50A determines the amount of load heat at the external load 65 based on the water temperature measured by the water temperature sensor 57A, the return water temperature measured by the return water temperature sensor 57B, and the flow rate Q measured by the flow meter 58. Calculate and adjust the number of operating heat source devices 51A and 51B based on this load heat quantity. In addition, when the number of operating heat source devices 51A and 51B is changed, the control device 50A controls the rotation speeds of the primary pumps 52A and 52B, respectively, so that the flow rate Q is maintained. Adjust the flow rate.
The secondary pump control device 50B adjusts the number of operating secondary pumps 54A, 54B, 54C based on the flow rate Q measured by the flow meter 58. Further, the rotational speed of the secondary pumps 54A, 54B, 54C is controlled to control the flow rate and the head, and the opening degree of the valve 56 is adjusted in order to return the excess heat source water in the forward header 53B to the forward header 53A. To do.

[Principle of calculation of pump characteristic value]
Next, with reference to FIG. 3 and FIG. 4, the principle of pump characteristic value calculation in the pump power calculation device according to the first embodiment of the present invention will be described. FIG. 3 is an explanatory diagram illustrating the principle of calculating the pump characteristic value, where the horizontal axis indicates the flow rate Q, the left vertical axis indicates the head H, and the right vertical axis indicates the shaft power. FIG. 4 is a schematic flowchart showing a process of calculating the pump characteristic value.

[Relationship between flow rate and head]
First, the relationship between the flow rate and the head when the rotation speed of the pump is controlled by an inverter will be described.
When the rotation speed N of the pump is controlled from the rated rotation speed N ₀ to the rotation speed N ₁ during control by inverter control, the discharge amount from the pump, that is, the flow rate Q, and the discharge pressure, that is, the lift H, are expressed by the following equation (1) The relationship shown in is established. In the formula (1), INV is the ratio N ₁ / N ₀ of the control when the rotational speed N ₁ to the rated rotational speed N _0, that is, the rotational speed ratio, K _1, K ₂ are constants.
H = K ₁ × INV ² −K ₂ × Q ² (1)

The operation characteristic indicating the relationship between the flow rate and the head represented by the equation (1) is referred to as a head curve. As can be seen from the equation (1), the lift curve moves in parallel in the direction along the left vertical axis in FIG. 3 according to the change in the rotational speed ratio INV. Here, the lift curve at the rated rotation speed N _0, that is, the rotation speed ratio INV = 1 (N ₀ / N ₀ = 100%) is referred to as the reference lift curve A _0, and the control rotation speed N _1, that is, the rotation speed ratio INV <1. The lift curve at (N ₁ / N ₀ ) is referred to as a control lift curve A ₁ .

Further, as can be seen from the equation (1), the head curve can be expressed by a quadratic function of the flow rate Q, and can be approximated by a function equation such as the following equation (2) when s, t, and u are constants. .
H = −s × Q ² + t × Q + u (2)
In general, the pump reference head curve A ₀ is a characteristic unique to the pump, and a reference head curve such as Expression (2) is provided from the manufacturer by a graph or a data table for each product.

On the other hand, when the load resistance of the pump is constant, the head H has an operating characteristic proportional to the square of the flow rate Q. Here, when α is a constant, it can be approximated by a function expression such as the following expression (3), and the operation characteristic indicating the flow rate-lift relationship represented by expression (3) is referred to as a resistance curve C.
H = α × Q ² (3)

The intersection of the lift curve A and the resistance curve C that move in parallel in accordance with the change in the rotational speed ratio INV in this way is referred to as an operating point R of the pump. Here, the operating point at the rated rotational speed N _0, that is, the rotational speed ratio INV = 1 (N ₀ / N ₀ = 100% = reference rotational speed ratio INV ₀ ) is referred to as the reference operating point R _0, and the control rotational speed N ₁ That is, the operating point at the rotational speed ratio INV <1 (N ₁ / N ₀ ) is referred to as a control operating point R ₁ . Further, the flow rate and the lift at the reference operating point R ₀ are referred to as a reference flow rate Q ₀ and a reference lift H ₀ , respectively, and the flow rate and the lift at the control operation point R ₁ are referred to as a control flow rate Q ₁ and a control lift H ₁ , respectively.

From this, if the control operating point R ₁ at the time of inverter control, that is, the control flow rate Q ₁ and the control lift H ₁ are known, the constant α of the equation (3) is calculated backward to obtain the equation (3), that is, the resistance The curve C can be specified. If the reference lift curve A ₀ provided in advance is stored as the equation (2), the intersection of the reference lift curve A ₀ and the resistance curve C can be expressed by the simultaneous equations of the equations (2) and (3). It can be specified as a solution. Therefore, the reference operating point R ₀ with respect to the control operating point R ₁ can be obtained in a state where the load resistance is constant, and conversely, any _{one of} the control flow rate Q ₁ , the control lifting head H ₁ , or the rotational speed ratio INV. If one is known, it is understood that the control operating point R ₁ can also be obtained from the reference operating point R ₀ .

In addition, when the inverter is controlled with a constant load resistance and the rotational speed ratio is changed from INV ₀ to INV ₁ , the pump operating state moves from the reference operating point R ₀ to the control operating point R ₁ , and the reference lift Curve A ₀ translates to control lift curve A ₁ . At this time, since the lift H is proportional to the square of the rotational speed ratio INV from the equation (1), the ratio between the reference lift H ₀ and the control lift H ₁ is the reference rotational speed ratio INV ₀ ² (= 1). and proportional to the ratio of control during rotation velocity ratio INV ₁ ^2. Therefore, the control lift H ₁ can be obtained from the reference lift H ₀ and the control rotation speed ratio INV ₁ based on the following equation (5).
H ₁ = H ₀ × INV ₁ ² (5)

Similarly, since the flow rate Q is proportional to the rotational speed ratio INV from the equation (1), the ratio between the reference flow rate Q ₀ and the control flow rate Q ₁ is the reference rotational speed ratio INV ₀ (= 1) and the control rotational speed. It is proportional to the ratio INV ₁ . Therefore, the control flow rate Q ₁ can be obtained from the reference flow rate Q ₀ and the control rotation speed ratio INV ₁ based on the following equation (6), and conversely from the control flow rate Q ₁ and the control rotation speed ratio INV _1. A reference flow rate Q ₀ can also be obtained.
Q ₁ = Q ₀ × INV ₁ (6)

Further, Equation (5) using, can also determine the reference lift H ₀ control during lift H ₁ from the control when the rotational speed ratio INV _1, a reference lift H ₀ and the control when the rotational speed ratio from the control when pump head H ₁ INV ₁ can also be obtained.
Similarly, the reference flow rate Q ₀ can be obtained from the control flow rate Q ₁ and the control rotation speed ratio INV ₁ using the equation (6), and the control rotation speed ratio from the reference flow rate Q ₀ and the control flow rate Q _1. INV ₁ can also be obtained.

[Relationship between flow rate and shaft power]
Next, the relationship between the flow rate and shaft power when the rotation speed of the pump is controlled by an inverter will be described.
In general, the discharge amount from the pump operating at the rated rotational speed N ₀ , that is, the flow rate Q and the power consumption of the pump, that is, the shaft power E, are represented by a reference shaft power curve B ₀ in FIG. Such a reference shaft power curve B ₀ of the pump is a characteristic unique to the pump, and is provided from the manufacturer by a graph or a data table for each individual product. The shaft power E can be expressed by a quadratic function of the flow rate Q. When a, b, and c are constants, the shaft power E can be approximated by a functional expression such as the following expression (7).
E = −a × Q ² + b × Q + c (7)

On the other hand, when the rotational speed N of the pump is inverter-controlled while the load resistance of the pump is constant, the shaft power E has an operation characteristic proportional to the cube of the flow rate Q. Here, when β is a constant, it can be approximated by a function expression such as the following expression (7). Here, during inverter control in a state where the load resistance of the pump is constant, the operation characteristic indicating the relationship between the flow rate and the shaft power expressed by the equation (8) is referred to as a control time shaft power curve B ₁ .
E = β × Q ³ (8)

Therefore, the power point P determined by the flow rate Q of the pump and its shaft power E moves on the same control time shaft power curve B ₁ according to the change in the rotational speed ratio INV. Here, the operating point at the rated rotational speed N _0, that is, the rotational speed ratio INV = 1 (N ₀ / N ₀ = 100%) is referred to as the reference power point P _0, and the control rotational speed N _1, that is, the rotational speed ratio INV <1. The power point at (N ₁ / N ₀ ) is referred to as a control power point P ₁ . The shaft power at the reference power point P ₀ is referred to as reference shaft power E _0, and the shaft power at the control power point P ₁ is referred to as control time shaft power E ₁ .

From this, if the control power point P ₁ at the time of inverter control, that is, the control flow rate Q ₁ and the control shaft power E ₁ are known, the constant β of the equation (8) is calculated backward to obtain the equation (8), The control time axis power curve B ₁ can be specified. Further, if the reference shaft power curve B ₀ provided in advance is stored as the equation (7), the intersection of the reference shaft power curve B ₀ and the control time shaft power curve B ₁ is expressed by the equations (7) and ( It can be specified as the solution of simultaneous equations in 8). Therefore, in a state where the load resistance is constant, the reference power point P ₀ for the control power point P ₁ can be obtained, and conversely, the control power point P ₁ can be obtained from the reference power point P _0. I understand.

Further, when the rotation speed ratio is changed from INV ₀ to INV ₁ by performing inverter control with a constant load resistance, the operation state of the pump moves from the reference power point P ₀ to the control power point P ₁ . In this case, the shaft power E from Equation (8) is proportional to the cube of the flow rate Q, since the flow rate Q is proportional to the rotational speed ratio INV from equation (6), the reference axis power E ₀ and the control when the shaft power E The ratio of ₁ is proportional to the ratio of the reference rotational speed ratio INV ₀ ³ (= 1) and the control rotational speed ratio INV ₁ ³ .

Therefore, the control-time shaft power E ₁ can be obtained from the reference shaft power E ₀ and the control-time rotation speed ratio INV ₁ based on the following equation (9).
E ₁ = E ₀ × INV ₁ ³ (9)
Further, using Equation (9), the control when the shaft power E ₁ and can also determine the reference axis power E ₀ from the control when the rotational speed ratio INV _1, the control from the control when the shaft power E ₁ the reference axis power E ₀ The hourly rotation speed ratio INV ₁ can also be obtained.

[Pump shaft power calculation process]
As described in the principle of calculating the pump characteristic value shown in FIG. 3, if the control operating point R ₁ or the reference operating point R ₀ is specified, the load on the pump at that time is based on the above-described equation (3). A resistance curve C corresponding to the resistance can be specified. Thus, when the reference lift curve A ₀ is known, the reference flow rate Q ₀ at the reference operation point R ₀ corresponding to the control operation point R ₁ in the state where the load resistance is constant, the reference lift curve A ₀ and the resistance curve C It can be calculated from the intersection of

At this time, if the control lift H ₁ and the control rotation speed ratio INV ₁ are known, the reference flow rate Q ₀ at the reference operating point R ₀ can be calculated based on the above-described equation (5). When the control flow rate Q ₁ and the control rotation speed ratio INV ₁ are known, the reference flow rate Q ₀ at the reference operating point R ₀ can be calculated based on the above-described equation (6).

Further, since the reference flow rate Q _{0 at} the reference operating point R ₀ and the reference power point P ₀ is the same, when the reference shaft power curve B ₀ is known, the power on the reference shaft power curve B _{0 at the} reference flow rate Q ₀ is known. The point can be specified as the reference power point P ₀ , and the shaft power at that time becomes the reference shaft power E ₀ .
Further, based on equation (8) described above, can determine the control time shaft power curve B ₁ from the reference power point P _0, the control time of the flow rate Q ₁ at the control during operation point R ₁ and the control during power point P ₁ is the same Therefore, the control-time shaft power E ₁ at the control-time power point P ₁ can be calculated from the control-time flow rate Q ₁ and the control-time power curve B ₁ .

As described above, there are several methods for calculating the reference flow rate Q ₀ . In the present embodiment, a case where the pump power value is calculated will be described by taking as an example a case where the reference flow rate Q ₀ is calculated from the control flow rate Q ₁ acquired as the input characteristic value 2 and the control lift H ₁ .
In the second embodiment to be described later, the reference flow rate Q ₀ is calculated from either the control flow rate Q ₁ or the control lift H ₁ acquired as the input characteristic value 2 and the control rotation speed ratio INV _1. As an example, the case of calculating the pump power value will be described.

[Configuration of pump power calculation device]
Next, the configuration of the pump power calculation device according to the first embodiment of the present invention will be described with reference to FIG.

  The data acquisition unit 11 includes a dedicated data communication circuit, and performs data communication with an external device such as each device of the pump system 5 to perform various information such as an input characteristic value 2 and a program related to a pump that is a characteristic value calculation target. It has the function to acquire. As the input characteristic value 2, the flow rate Q and the head H relating to the pump for which the characteristic value is to be calculated are acquired. At this time, in the pump system of FIG. 2, for example, the flow rate value (discharge amount) measured by the flow meter 58 may be acquired as the flow rate Q, and the differential pressure measured by the differential pressure meter 55 may be acquired as the head H.

The operation input unit 12 includes an operation input device such as a keyboard and a mouse, and has a function of detecting various operations such as start of pump power calculation processing by an operator and outputting the operation to the arithmetic processing unit 16.
The screen display unit 13 includes a screen display device such as an LCD or a PDP, and has a function of displaying various information such as an operation menu screen and a pump power value 3 on the screen in accordance with an output from the arithmetic processing unit 16. .
The data output unit 14 includes a dedicated data communication circuit, and has a function of outputting the pump power value 3 calculated by the arithmetic processing unit 16 by performing data communication with an external device such as each device of the pump system 5. doing.

The storage unit 15 includes a storage device such as a memory and a hard disk, and has a function of storing various processing information and a program 15P used for pump power calculation processing in the arithmetic processing unit 16. Among these, the program 15P is a program that is read and executed by the arithmetic processing unit 16 and implements various processing units that perform pump power calculation processing. The storage unit 15 is previously stored in the storage unit 15 via the data acquisition unit 11 from an external device or a recording medium. Stored in
Main processing information stored in the storage unit 15 includes a reference lift curve function equation 15A, a reference shaft power curve function equation 15B, a function shape equation 15C, and pump attribute information 15D.

The reference lift curve function formula 15A is a function expression showing the relationship between the pump flow rate Q and the lift H at the rated rotational speed N ₀ (rotational speed ratio = INV ₀ ), that is, the reference lift curve.
The reference shaft power curve function expression 15B is a function expression showing the relationship between the pump flow rate Q and the shaft power E at the rated rotational speed N ₀ (rotational speed ratio = INV ₀ ), that is, the reference shaft power curve.

The reference lift curve function formula 15A and the reference shaft power curve function formula 15B are function formulas in which all constants are fixed, and function formulas attached in advance as technical data to the pump may be used as drawings and data. In the case of attachment, a function formula may be calculated in advance from these drawings and data.
On the other hand, the function shape formula 15C is various function formulas indicating the operating characteristics of the pump, such as a resistance curve and a control time axis power curve. These function expressions are expressions that indicate only the shape of a function such as a quadratic function or a cubic function without constants being determined.

The pump attribute information 15D is attribute information indicating the characteristics of the pump. For example, a value obtained empirically may be used. The pump attribute information 15D includes an electric motor efficiency η _m indicating the power transmission efficiency in the electric motor that rotationally drives the pump, and an inverter efficiency η _i indicating the electric power transmission efficiency in the inverter that controls the rotational speed of the electric motor.

The arithmetic processing unit 16 includes a microprocessor such as a CPU and its peripheral circuits, and reads and executes the program 15P in the storage unit 15 to cause the hardware and the program 15P to cooperate with each other to perform pump power calculation processing. It has a function to realize various processing units necessary for the system.
As main processing units realized by the arithmetic processing unit 16, there are a reference flow rate calculation unit 16A, a reference shaft power calculation unit 16B, and a power calculation unit 16C.

Based on the input characteristic value 2 acquired by the data acquisition unit 11, the reference flow rate calculation unit 16 </ b> A is a resistance indicating the relationship between the pump flow rate and the head when the pump rotation speed is controlled with the pump piping resistance being constant. It has a function of calculating a reference flow rate at a reference operating point that is an intersection of the curve and the reference lift curve of the storage unit 15.
Based on the reference flow rate calculated by the reference flow rate calculation unit 16A, the reference shaft power calculation unit 16B obtains the relationship between the pump flow rate and the shaft power when the pump rotation speed is controlled with the pump piping resistance being constant. It has a function of calculating the reference shaft power of the pump at the reference power point that is the intersection of the control time shaft power curve shown and the reference shaft power curve of the storage unit 15.

  The power calculation unit 16C performs control based on the reference flow rate calculated by the reference flow rate calculation unit 16A, the reference shaft power calculated by the reference shaft power calculation unit 16B, and the control time axis power curve function shape formula of the storage unit 15. A function for specifying the shaft power curve, a function for calculating the control time shaft power at the control time power point as the pump power value 3 from the control flow rate and the control time shaft power curve, and the calculated pump power value 3 on the screen display unit. 13 has a function of displaying a screen or outputting the data from the data output unit 14 to an external device such as the pump system 5.

[Operation of First Embodiment]
Next, with reference to FIGS. 5-8, operation | movement of the pump power calculation apparatus concerning the 1st Embodiment of this invention is demonstrated. FIG. 5 is a flowchart showing a pump power calculation process of the pump power calculation apparatus according to the first embodiment of the present invention. FIG. 6 is a flowchart showing a pump power calculation process of the pump power calculation apparatus according to the first embodiment of the present invention. FIG. 7 is a flowchart showing a reference flow rate calculation process in the pump power calculation process of FIG. FIG. 8 is a flowchart showing a reference shaft power calculation process in the pump power calculation process of FIG.

  The calculation processing unit 16 of the pump power calculation device 1 performs the pump power calculation process of FIGS. 5 and 6 by the power calculation unit 16C in response to the start instruction operation of the pump power calculation process by the operator detected by the operation input unit 12. To start.

The power calculation unit 16C first acquires the control flow rate Q ₁ and the control lift H ₁ indicating the control operation point R ₁ from the pump system 5 via the data acquisition unit 11 and temporarily stores them in the storage unit 15. (Step 100).
Next, the power calculation unit 16C performs a reference flow rate calculation process of FIG. 7 described later by the reference flow rate calculation unit 16A to calculate a reference flow rate Q ₀ (step 101).
Subsequently, the power calculation unit 16C performs a reference shaft power calculation process of FIG. 8 described later by the reference shaft power calculation unit 16B to calculate a reference shaft power E ₀ (step 102).

Thereafter, the power calculation unit 16C reads out the reference flow rate Q ₀ calculated by the reference flow rate calculation unit 16A and the reference shaft power E ₀ calculated by the reference shaft power calculation unit 16B from the storage unit 15 (step 103). ), The above-described equation (9) is read out from the function shape equation 15C of the storage unit 15 as the function shape equation of the control time axis power curve B ₁ (step 104), and the constant β is determined from the reference flow rate Q ₀ and the reference shaft power E _0. Calculate (step 105). Thus, the control time axis power curve B ₁ is specified.

Then, the power calculation unit 16C reads out the control time flow rate to Q ₁ control when the operating point R ₁ from the storage unit 15 (step 106), upon control from the control when the flow rate Q ₁ and the control when the shaft power curve B ₁ Metropolitan A shaft power E ₁ is calculated (step 107). Thus, control upon shaft power curve B control when the power point P ₁ on ₁ is identified, and temporarily stores the control time shaft power E ₁ to the memory unit 15 (step 108).

Next, the power calculation unit 16C reads out the motor efficiency η _m and the inverter efficiency η _i from the pump attribute information 15D in the storage unit 15 (step 109), and based on the following equation (10), the control power point P ₁ calculating the power consumption W ₁ of the pump in the (step 110).
W ₁ = E ₁ ÷ (η _m × η _i ) (10)
Thereafter, the power calculation unit 16C outputs the calculated power consumption W ₁ to the screen display unit 13 or the data output unit 14, or stores it in the storage unit 15, and ends the series of pump power calculation processes.

[Reference flow rate calculation processing]
The reference flow rate calculation unit 16A starts the reference flow rate calculation process of FIG. 7 in response to an instruction from the power calculation unit 16C.
First, the reference flow rate calculation unit 16A reads the control at flow rates Q ₁ and control during lift H ₁ showing the control when the operating point R ₁ from the storage unit 15 (step 120), the resistance from the function-shaped type 15C in the storage unit 15 The above-described equation (3) is read as the function shape equation of the curve C (step 121), and a constant α is calculated from the control flow rate Q ₁ and the control lift H ₁ (step 122). Thereby, the resistance curve C is specified.

Subsequently, the reference flow rate calculation unit 16A reads the reference lift curve function formula 15A in which the constant of the above-described equation (2) is fixed as the reference lift curve A ₀ from the storage unit 15 (step 123), for example, the reference lift By solving the curve A ₀ and the resistance curve C as simultaneous equations, the intersection of the reference lift curve A ₀ and the resistance curve C, that is, the reference operating point R ₀ is specified, and the reference flow rate Q ₀ is calculated and obtained. The reference flow rate Q ₀ is temporarily stored in the storage unit 15 (step 124), and a series of reference flow rate calculation processing is terminated.

[Reference shaft power calculation processing]
The reference shaft power calculation unit 16B starts the reference shaft power calculation process of FIG. 8 in response to an instruction from the power calculation unit 16C.
First, the reference shaft power calculation unit 16B reads the reference flow rate Q ₀ from the storage unit 15 (step 130), and the reference in which the constant of the formula (7) is determined as the reference shaft power curve B ₀ from the storage unit 15 is obtained. The shaft power curve function formula 15B is read (step 131).
Subsequently, the reference shaft power calculation unit 16B calculates the reference shaft power E ₀ from the reference flow rate Q ₀ and the reference shaft power curve B ₀ and temporarily stores the reference shaft power E ₀ in the storage unit 15 (step 132). ), A series of reference shaft power calculation processing ends.

[Effect of the first embodiment]
As described above, in the present embodiment, the reference operating point R formed by the intersection of the resistance curve C and the reference lift curve A ₀ based on the input characteristic value 2 acquired by the data acquisition unit 11 by the reference flow rate calculation unit 16A. calculating a reference flow rate Q ₀ of _0, the reference axis power calculating section 16B, based on the reference flow rate Q ₀ calculated by the reference flow rate calculation unit 16A, a control during shaft power curve B ₁ and the reference axis power curve B ₀ calculating a reference axis power E ₀ of the pump at the reference power point P ₀ consisting of the intersection, by the power calculation unit 16C, are calculated by the reference flow rate Q ₀ and a reference axis power calculating portion 16B which is calculated by the reference flow rate calculation unit 16A The control time axis power curve B ₁ is specified based on the reference shaft power E ₀ and the control time axis power curve function shape formula of the storage unit 15, and control is performed from the control flow rate Q ₁ and the control time axis power curve B _1. when the control time shaft power E ₁ in the power point P ₁ Calculated as the pump power value 3.

At this time, the function shape formula relating to the resistance curve C is stored in the storage unit 15, and the control flow rate Q ₁ and the control lift H ₁ related to the pump are acquired as the input characteristic value 2 by the data acquisition unit 11. Based on the input characteristic value 2 acquired by the data acquisition unit 11 and the function shape formula related to the resistance curve C of the storage unit 15 by the flow rate calculation unit 16A, the resistance curve C passing through the control operating point R ₁ is specified. The flow rate at the intersection of the resistance curve C and the reference lift curve A ₀ of the reference lift curve function formula 15A of the storage unit 15 is calculated as the reference flow rate Q ₀ .

Therefore, according to the present embodiment, the control-time shaft power E ₁ that is required when the pump is operated at the operating point based on the control-time flow rate Q ₁ indicating the arbitrary operating point and the control-time head H _1. The power consumption W ₁ can be calculated as the pump power value 3.
Therefore, by comparing the pump power value 3 corresponding to each operation point based on the control flow rate Q ₁ and the control lift H ₁ at different operation points, the pump operation point and control algorithm can be determined from the viewpoint of energy saving. By changing, it becomes possible to very easily study the reduction of shaft power and power consumption required for the pump.

Further, according to the present embodiment, since the resistance curve and the control time axis power curve can be specified based on the input characteristic value 2, the operation characteristic data of the pump such as the lift curve, the shaft power curve, the resistance curve, There is no need to measure in advance for each rotation speed of the pump. For this reason, the work burden concerning the preparatory work for calculating a pump characteristic value can be reduced.
In addition, the resistance curve and control time axis power curve can be specified regardless of the value of the pump rotation speed, and approximate to the case where discrete operating characteristic data is used for the pump rotation speed. There is no need to perform processing or interpolation processing. For this reason, the characteristic value of the pump can be calculated with high accuracy.

[Second Embodiment]
Next, with reference to FIG. 9, a pump power calculation apparatus according to a second embodiment of the present invention will be described. FIG. 9 is a flowchart showing the reference flow rate calculation process of the pump power calculation device according to the second embodiment of the present invention.
In the first embodiment, the case where the control flow rate Q ₁ and the control lift H ₁ are used as the input characteristic value 2 has been described as an example. In the present embodiment, a case where the control flow rate Q ₁ and the control rotation speed ratio INV ₁ are used as the input characteristic value 2 will be described.

In this embodiment, the reference flow rate calculation unit 16A calculates the reference flow rate Q ₀ from the control flow rate Q ₁ acquired as the input characteristic value 2 and the control rotation speed ratio INV ₁ in the first implementation. The form is different. Other configurations in the pump power calculation apparatus according to the present embodiment are the same as those in the first embodiment, and a detailed description thereof is omitted here.

[Operation of Second Embodiment]
Next, with reference to FIGS. 6 and 9, the pump power calculation process according to the second embodiment of the present invention will be described.
The calculation processing unit 16 of the pump power calculation device 1 starts the pump power calculation process of FIG. 6 by the power calculation unit 16C in response to the start instruction operation of the pump power calculation process by the operator detected by the operation input unit 12. .

First, in step 100 of FIG. 6, the power calculation unit 16C acquires the control flow rate Q ₁ and the control rotation speed ratio INV ₁ indicating the control operation point R ₁ from the pump system 5 via the data acquisition unit 11. And temporarily stored in the storage unit 15.
Next, the motive power calculation unit 16C performs a reference flow rate calculation process of FIG. 9 described later by the reference flow rate calculation unit 16A to calculate a reference flow rate Q ₀ (step 101).
The subsequent steps 102 to 110 and the reference shaft power calculation process (see FIG. 8) by the reference shaft power calculation unit 16B are the same as those in the first embodiment, and detailed description thereof is omitted here.

[Reference flow rate calculation processing]
The reference flow rate calculation unit 16A starts the reference flow rate calculation process of FIG. 9 in response to an instruction from the power calculation unit 16C.
First, the reference flow rate calculation unit 16A includes a control time flow rate Q ₁ showing the control when the operating point R ₁ from the storage unit 15 reads out a control when the rotational speed ratio INV ₁ (step 200), shown in Equation (6) described above based on the relationship of the flow rate and the rotational speed ratio, to calculate the reference flow rate Q ₀ at the reference operating point R ₀ from the control when the flow rate Q ₁ and the control when the rotational speed ratio INV ₁ Prefecture, the reference flow rate Q ₀ to the memory unit 15 Temporary storage is performed (step 201), and a series of reference flow rate calculation processing ends.

[Effect of the second embodiment]
In this manner, in the present embodiment, the data acquisition unit 11 acquires the time control relating to the pump flow rate Q ₁ and the control when the rotational speed ratio INV1 as the input characteristic value 2, the reference flow rate calculation unit 16A, the data acquisition unit since to calculate the reference flow rate Q ₀ at the reference operating point R ₀ on the basis of the time obtained controlled flow rate Q ₁ and the control when the rotational speed ratio INV1 to 11, even if the control time lift H ₁ can not be obtained The reference flow rate Q ₀ can be calculated based on the control flow rate Q ₁ and the control rotation speed ratio INV 1, and the same operational effects as those of the first embodiment can be obtained.

[Third Embodiment]
Next, with reference to FIG. 10, a pump power calculation apparatus according to a third embodiment of the present invention will be described. FIG. 10 is a flowchart showing a reference flow rate calculation process of the pump power calculation device according to the third embodiment of the present invention.
In the first embodiment, the case where the control flow rate Q ₁ and the control lift H ₁ are used as the input characteristic value 2 has been described as an example. In the present embodiment, a case will be described in which the control lift H ₁ and the control rotation speed ratio INV ₁ are used as the input characteristic value 2.

In the case of the present embodiment, the reference flow rate calculation unit 16A calculates the reference flow rate Q ₀ from the control lift H ₁ acquired as the input characteristic value 2 and the control rotation speed ratio INV ₁ in the first implementation. The form is different. Other configurations in the pump power calculation apparatus according to the present embodiment are the same as those in the first embodiment, and a detailed description thereof is omitted here.

[Operation of Third Embodiment]
Next, with reference to FIG. 6 and FIG. 10, a pump power calculation process according to the third embodiment of the present invention will be described.
The calculation processing unit 16 of the pump power calculation device 1 starts the pump power calculation process of FIG. 6 by the power calculation unit 16C in response to the start instruction operation of the pump power calculation process by the operator detected by the operation input unit 12. .

First, in step 100 of FIG. 6, the power calculation unit 16C acquires the control-time head H ₁ and the control-time rotation speed ratio INV ₁ indicating the control-time operating point R ₁ from the pump system 5 via the data acquisition unit 11. And temporarily stored in the storage unit 15.
Next, the power calculation unit 16C uses the reference flow rate calculation unit 16A to execute a reference flow rate calculation process of FIG. 10 described later to calculate a reference flow rate Q ₀ (step 101).
The subsequent steps 102 to 110 and the reference shaft power calculation process (see FIG. 8) by the reference shaft power calculation unit 16B are the same as those in the first embodiment, and detailed description thereof is omitted here.

[Reference flow rate calculation processing]
The reference flow rate calculation unit 16A starts the reference flow rate calculation process of FIG. 10 in response to an instruction from the power calculation unit 16C.
First, the reference flow rate calculation unit 16A includes a storage unit 15 during control of a control at the operating point R ₁ pump head H ₁ and reads out the control during the rotation speed ratio INV ₁ from (step 210), shown in Equation (5) described above based on the relationship of lift and rotation speed ratio, to calculate the reference lift H ₀ at the reference operating point R ₀ from the control when pump head H ₁ and the control when the rotational speed ratio INV ₁ Tokyo (step 211).

Next, the reference flow rate calculation unit 16A reads the reference lift curve function equation 15A in which the constant of the above-described equation (2) is fixed as the reference lift curve A ₀ from the storage unit 15 (step 212). Applying the reference head H ₀ , the reference flow rate Q ₀ at the reference operating point R ₀ is calculated backward, the obtained reference flow rate Q ₀ is temporarily stored in the storage unit 15 (step 213), and a series of reference flow rate calculation processes is completed. To do.

[Effect of the third embodiment]
As described above, in this embodiment, the data acquisition unit 11 acquires the control-time head H ₁ and the control-time rotation speed ratio INV1 related to the pump as the input characteristic value 2, and the reference flow rate calculation unit 16A acquires the data acquisition unit. since to calculate the reference flow rate Q ₀ at the reference operating point R ₀ on the basis of the time obtained controlled lift H ₁ and the control when the rotational speed ratio INV1 to 11, even if the control time flow rate Q ₁ is not obtained The reference flow rate Q ₀ can be calculated based on the control lift H ₁ and the control rotation speed ratio INV 1, and the same effects as those of the first embodiment can be obtained.

[Extended embodiment]
In each of the above-described embodiments, the example in which the desired unknown pump power value 3 is calculated using each formula described in the principle of the pump characteristic value calculation has been described. However, how to use each formula is described above. It is not limited to the example. In the case where there are a plurality of methods for calculating an arbitrary characteristic value using different equations, any method may be used.

  Further, in each embodiment, the pump power value 3 has been described as an example in which shaft power and power consumption required in the operation state of the pump specified by the input characteristic value 2 are calculated and output. However, the present invention is not limited to this. Is not to be done. For example, the input characteristic value 2 indicating two different operation states is acquired by the data acquisition unit 11, the shaft power and the power consumption are calculated for each of the input characteristic values 2, and the difference between the shaft power and the power consumption, that is, the shaft The power difference or the power consumption difference may be calculated by the power calculation unit 16C and output as the pump power value 3. Furthermore, the ratio of the shaft power and power consumption, that is, the shaft power ratio and power consumption ratio may be calculated by the power calculation unit 16C and output as the pump power value 3. As a result, specific numerical values such as an energy reduction amount and an energy reduction rate (energy saving rate) can be output as the degree of energy saving in the pump.

  Moreover, in each embodiment, the pump of the general air conditioning equipment provided in an office building, a public facility, a hotel, etc. as shown in FIG. Although the system 5 has been described, the present invention is not limited to this. If the pump system is provided with an inverter in the pump to variably control the pump rotation speed, the air conditioning equipment of other configurations Each embodiment of the present invention can be applied to a system other than an air conditioner that supplies heat source water to an external load with a secondary pump, for example, a system that blows air with a pump, and similar effects can be obtained. .

  Moreover, although each embodiment demonstrated as an example the case where the data acquisition part 11 calculated an unknown characteristic value based on each input characteristic value 2 measured with the pump system 5, it is not limited to this. Absent. For example, an input characteristic value 2 stored in a personal computer or a storage medium or an input characteristic value 2 input from the operation input unit 12 is acquired by the data acquisition unit 11, and an unknown characteristic value is calculated based on the input characteristic value 2. You may make it do. Furthermore, the obtained pump power value 3 may be output from the data output unit 14 to a personal computer or a storage medium.

It is a block diagram which shows the structure of the pump power calculation apparatus concerning the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the pump system used as the process target of a pump power calculation apparatus. It is explanatory drawing which shows the principle of pump characteristic value calculation. It is a schematic flowchart which shows the calculation process of a pump characteristic value. It is a flowchart which shows the pump power calculation process of the pump power calculation apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows the pump power calculation process of the pump power calculation apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows the reference | standard flow volume calculation process in the pump power calculation process of FIG. It is a flowchart which shows the reference shaft power calculation process in the pump power calculation process of FIG. It is a flowchart which shows the reference | standard flow volume calculation process of the pump power calculation apparatus concerning the 2nd Embodiment of this invention. It is a flowchart which shows the reference | standard flow volume calculation process of the pump power calculation apparatus concerning the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pump power calculation apparatus, 11 ... Data acquisition part, 12 ... Operation input part, 13 ... Screen display part, 14 ... Data output part, 15 ... Memory | storage part, 15A ... Reference | standard lift curve function formula, 15B ... Reference | standard shaft power curve Function formula, 15C ... Function shape formula, 15D ... Pump attribute information, 15P ... Program, 16 ... Calculation processing unit, 16A ... Reference flow rate calculation unit, 16B ... Reference shaft power calculation unit, 16C ... Power calculation unit, 2 ... Input characteristics Value, 3 ... Pump power value, 5 ... Pump system, 50A ... Control device, 50B ... Secondary pump control device, 51A, 51B ... Heat source machine, 52A, 52B ... Primary pump, 53A, 53B ... Out header, 54A, 54B, 54C ... secondary pump, 55 ... differential pressure gauge, 56 ... valve, 57A ... outgoing water temperature sensor, 57B ... return water temperature sensor, 58 ... flow meter, 59 ... return header, 60 ... bypass line, 6 , 62 ... heat pipe, 63 ...往水pipe, 64 ... Kaemizu pipe, 65 ... external load, Q ... flow, Q ₀ ... reference flow, Q ₁ ... control when the flow rate, H ... lift, H ₀ ... reference lift , H ₁ ... control head, E ... shaft power, E ₀ ... reference shaft power, E ₁ ... control shaft power, INV ... rotational speed ratio, INV ₀ ... reference rotational speed ratio, INV ₁ ... control rotational speed ratio , A ₀ ... reference lift curve, A ₁ ... control lift curve, B ₀ ... reference shaft power curve, B ₁ ... control shaft power curve, C ... resistance curve, R ₀ ... reference operating point, R ₁ ... control Operating point, P ₀ ... Reference power point, P ₁ ... Power point during control.

Claims (2)

For pump rotational speed N is variably controlled in any of the control when the rotational speed N _1, two characteristic values indicating the operating condition of the pump, calculates a pump power value indicating a power required by the pump in the operating conditions A pump power calculation device for
A reference head curve A ₀ indicating the pump regarding flow rate and the lift relationship at a predetermined reference rotational speed N _0, the reference axis power curve B ₀ showing the relationship between flow rate and shaft power for Pump at said reference rotational speed N ₀ A resistance curve function shape formula approximating a resistance curve C indicating the relationship between the pump flow rate and the head when the pump rotational speed N is controlled while the pump pipe resistance is constant, and the pump pipe resistance is constant. a control when the shaft power curve function shape equation approximating the control during shaft power curve B ₁ showing the relationship between pump flow and shaft power at the time of controlling the rotational speed N of the pump in the motor efficiency eta _m and inverter efficiency of the pump a storage unit for storing and eta _i,
A data acquisition unit that acquires control at flow rates Q ₁ and control during lift H ₁ showing the characteristics of the pump in operation in the control when the rotational speed N ₁ as the input characteristic values,
The resistance curve C is specified by calculating a constant of the resistance curve function shape formula in the storage unit based on the control operating point R ₁ specified by the input characteristic value acquired by the data acquisition unit. , by identifying the reference operating point R ₀ consisting of the intersection between the reference head curve a ₀ of the storage unit and the resistance curve C, a reference flow rate calculation unit that calculates a reference flow rate Q ₀ in the reference operating point R ₀ When,
Based on the above reference flow rate Q ₀ and the reference axis power curve B ₀ of the memory unit in the reference operating point R _0, identifies the reference power point P ₀ at the time of operating the pump at the reference rotational speed N ₀ by the reference axis power calculation unit for calculating a reference axis power E ₀ in the reference power point P _0,
Based on the reference flow rate Q ₀ and the reference shaft power E _{0 at the} reference power point P _0, the control of the storage unit is calculated by calculating a constant of the control time axis power curve function shape formula of the storage unit. When the time axis power curve B ₁ is specified and the pump is operated at the control rotation speed N ₁ from the control time axis power curve B ₁ and the control flow rate Q ₁ acquired by the data acquisition unit . A control time shaft power E ₁ is calculated, and a pump control power consumption W ₁ is calculated as the pump power value from the control time shaft power E ₁ , the motor efficiency η _{m of the} storage unit, and the inverter efficiency η _i. A pump power calculation device comprising: a power calculation unit configured to Rotational speed N is any control rotational speed N ₁ The pump power calculation method used in the pump power calculation device for calculating the pump power value indicating the power required for the pump in the operation status from the two characteristic values indicating the operation status of the pump. Because
The storage unit has a predetermined reference rotational speed N ₀ Reference head curve A showing the relationship between flow rate and head for pumps ₀ And the reference rotational speed N ₀ Reference shaft power curve B showing the relationship between flow rate and shaft power for pumps ₀ And a resistance curve function shape equation approximating a resistance curve C indicating the relationship between the pump flow rate and the head when the pump rotational speed N is controlled in a state where the pump piping resistance is constant, and the pump piping resistance is constant. Control time axis power curve B showing the relationship between the pump flow rate and the shaft power when the rotational speed N of the pump is controlled in the state ₁ Is the control time axis power curve function shape formula and the pump motor efficiency η _m And inverter efficiency η _i A memory step for storing
The data acquisition unit performs the control rotation speed N ₁ Control flow rate Q showing the characteristics of the pump in operation ₁ And control head H ₁ A data acquisition step of acquiring as an input characteristic value;
A control operating point R specified by the input characteristic value acquired in the data acquisition step by the reference flow rate calculation unit ₁ The resistance curve C is specified by calculating a constant of the resistance curve function shape formula of the storage unit based on the resistance curve C and the reference lift curve A of the storage unit. ₀ Reference point R consisting of the intersection with ₀ By specifying the reference operating point R ₀ Reference flow rate Q ₀ A reference flow rate calculating step for calculating
The reference shaft power calculation unit is configured to output the reference operating point R ₀ Reference flow rate Q at ₀ And the reference shaft power curve B of the storage unit ₀ Based on the reference rotational speed N ₀ Reference power point P when the pump is operated at ₀ By specifying the reference power point P ₀ Reference shaft power E ₀ A reference shaft power calculation step for calculating
The power calculation unit is configured to output the reference power point P ₀ Reference flow rate Q at ₀ And the reference shaft power E ₀ Based on the above, the control time axis power curve B of the storage unit is calculated by calculating a constant of the control time axis power curve function shape formula of the storage unit. ₁ This control time axis power curve B ₁ And the control flow rate Q acquired in the data acquisition step. ₁ From the above, the control rotation speed N ₁ Control shaft power E when operating the pump with ₁ Is calculated, and the control shaft power E ₁ And the motor efficiency η of the storage unit _m And the inverter efficiency η _i And power consumption W during pump control ₁ A power calculation step for calculating the pump power value as
A pump power calculation method comprising:

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