JP5337290B2 - Pump characteristic value calculation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To calculate a characteristic value of a pump with high accuracy without measuring operation characteristic data of the pump in advance. <P>SOLUTION: A device for calculating a pump characteristic value includes: a reference operating point identifying part 16A for identifying a resistance curve C based on an operating point in control R<SB POS="POST">1</SB>of an input characteristic value, and identifying a reference operating point R<SB POS="POST">0</SB>specified as an intersection of the resistance curve C and a reference head-capacity curve A<SB POS="POST">0</SB>, thereby calculating a reference flow rate Q<SB POS="POST">0</SB>at the reference operating point R<SB POS="POST">0</SB>; and a reference point-of-power identifying part 16B for identifying a reference point of power P<SB POS="POST">0</SB>at reference rotational speed N<SB POS="POST">0</SB>based on the reference flow rate Q<SB POS="POST">0</SB>at the reference operating point R<SB POS="POST">0</SB>and a reference shaft power curve B<SB POS="POST">0</SB>, thereby calculating reference shaft power E<SB POS="POST">0</SB>at the reference point of power P<SB POS="POST">0</SB>. In a characteristic value calculating part 16C, a shaft power curve in control B<SB POS="POST">1</SB>is identified based on the reference flow rate Q<SB POS="POST">0</SB>and the reference shaft power E<SB POS="POST">0</SB>at the reference point of power P<SB POS="POST">0</SB>. Shaft power in control E<SB POS="POST">1</SB>at rotational speed in control N<SB POS="POST">1</SB>is calculated as an output characteristic value from the shaft power curve in control B<SB POS="POST">1</SB>and a flow rate in control Q<SB POS="POST">1</SB>. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  The present invention relates to a pump control technique, and more particularly to a technique for calculating various characteristic values indicating the operation characteristics 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 the power consumption of 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

However, in such a conventional technique, there is a problem in the burden required for the preparation work for calculating the pump characteristic value and the accuracy of the calculation result.
That is, according to the prior art, when calculating the pump characteristic value, the head curve data, shaft power curve data, and resistance curve data corresponding to the input pump rotation speed are selected and used. For this reason, it is necessary to measure pump operating characteristic data such as a head curve, a shaft power curve, and a resistance curve in advance for each rotation speed of the pump, and there is a burden required for preparation work for calculating a pump characteristic value. Very big. In particular, as can be seen from the fact that pumps (motors) are given a lift curve and a shaft power curve in their ratings, even if they are products of the same standard, their characteristics vary greatly. For this reason, in order to calculate characteristic values for different arbitrary pumps, it is necessary to measure each operation characteristic in advance for each rotation speed of the pump, and such a work load is not realistic.

Also, when measuring the operating characteristics for each pump rotation speed, the work load can be reduced by increasing the interval (resolution) between these rotation speeds, but when calculating characteristic values for intermediate rotation speeds that have not been measured. In this case, the operation characteristic data having a close rotational speed is used, or the data interpolated with the operation characteristic data having a close rotational speed is used, which causes an error in the calculation result. Similar errors also occur when using typical pump head curve data, shaft power curve data, and resistance curve data.
The present invention is intended to solve such a problem, and provides a pump characteristic value calculation device capable of calculating a pump characteristic value with high accuracy without measuring pump operating characteristic data in advance. It is an object.

In order to achieve such an object, the pump characteristic value calculation device according to the present invention includes a plurality of pump operating conditions of a pump whose rotational speed N is variably controlled at an arbitrary control rotational speed N ₁ . A pump characteristic value calculation device for calculating an unknown characteristic value as an output characteristic value from an inputted known input characteristic value among characteristic values, and a relationship between a flow rate related to a pump and a lift at a predetermined reference rotational speed N ₀ The reference head curve A ₀ indicating the relationship between the pump flow rate and the shaft power at the reference rotation speed N ₀ , the reference shaft power curve B ₀ indicating the relationship between the shaft power and the pump rotation speed N with the pump pipe resistance being constant. A resistance curve function shape formula approximating a resistance curve C indicating the relationship between the pump flow rate and the head at the time of control, and the pump flow rate and shaft when the pump rotational speed N is controlled with the pump pipe resistance being constant. Power relationship A storage unit for storing a control time axis power curve function shape formula approximating the control time axis power curve B ₁ indicating the control time, and a control flow rate Q ₁ indicating the characteristics of the pump operating at the control rotation speed N _1. A data acquisition unit that acquires the control head H ₁ as the input characteristic value, and the control operation point R ₁ specified by the input characteristic value acquired by the data acquisition unit, the storage unit By calculating the constant of the resistance curve function shape formula, the resistance curve C is specified, and the reference operating point R ₀ consisting of the intersection of the resistance curve C and the reference lift curve A ₀ of the storage unit is specified. based the reference operating point specifying unit for calculating a reference flow rate Q ₀ in the reference operating point R _0, in 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 , operating the pump at the reference rotational speed N ₀ By identifying the reference power point P ₀ when the reference and the reference power point specifying unit for calculating a reference axis power E ₀ in the reference power point P _0, and the reference flow rate Q ₀ of the reference power point P ₀ Based on the shaft 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 shaft power A characteristic for calculating a control-time shaft power E ₁ when the pump is operated at the control rotation speed N ₁ as the output characteristic value from the curve B ₁ and the control-time flow rate Q ₁ acquired by the data acquisition unit. A value calculation unit.

According to the present invention, since a resistance curve and a control time axis power curve can be specified based on an input characteristic value, pump operating characteristic data such as a head curve, a shaft power curve, and a resistance curve can be obtained for each rotation speed of the pump. It is not necessary to measure in advance. 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.

It is a block diagram which shows the structure of the pump characteristic value 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 characteristic value 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 characteristic value calculation process (when control axial power is an output characteristic value) of the pump characteristic value calculation apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows the pump characteristic value calculation process (when control-time axial power is an output characteristic value) of the pump characteristic value calculation apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows the reference | standard driving | operation point specific process in the pump characteristic value calculation process of FIG. It is a flowchart which shows the reference | standard power point specific process in the pump characteristic value calculation process of FIG. It is a flow figure showing pump characteristic value calculation processing (when control time axis power is included in an input characteristic value) of a pump characteristic value calculation device concerning a 1st embodiment of the present invention. It is a flowchart which shows the pump characteristic value calculation process (when control-time axial power is contained in an input characteristic value) of the pump characteristic value calculation apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows the reference | standard power point specific process in the pump characteristic value calculation process of FIG. It is a flowchart which shows the reference | standard driving | operation point specific process in the pump characteristic value calculation process of FIG. It is a flowchart which shows the pump characteristic value calculation process of the pump characteristic value calculation apparatus concerning the 2nd Embodiment of this invention. It is a flowchart which shows the pump characteristic value calculation process of the pump characteristic value calculation apparatus concerning the 3rd Embodiment of this invention.

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

  The pump characteristic value 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 the pump system 5 variably controls the rotation speed at an arbitrary control rotation speed. The pump has a function of calculating an unknown characteristic value as an output characteristic value 3 from a known input characteristic value 2 among a plurality of characteristic values indicating the operation status of the pump.

  The pump characteristic value calculation apparatus 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 operating point specifying unit 16A, a reference power point specifying unit 16B, and a characteristic value calculating unit 16C as processing units that perform pump characteristic value calculation processing.

  In the present embodiment, the arithmetic processing unit 16 has a resistance curve indicating the relationship between the pump flow rate and the head when the pump rotational speed is controlled based on an arbitrary characteristic value while the pump piping resistance is constant. A reference operating point specifying unit 16A that calculates a reference flow rate or a reference lift of the pump when operating at a reference rotational speed by specifying a reference operating point consisting of an intersection with the reference head curve of the storage unit 15, and an arbitrary characteristic Based on the intersection of the control time axis power curve indicating the relationship between the pump flow rate and shaft power when the pump rotational speed is controlled with the pump piping resistance being constant based on the value and the reference shaft power curve of the storage unit A reference power point specifying unit 16B for calculating a reference flow rate or a reference shaft power of the pump when operating at a reference rotational speed by specifying a reference power point, and a characteristic value calculating unit 16C of the arithmetic processing unit 16 Then, based on the input characteristic value 2, the reference operating point specifying unit 16A and the reference operating point specifying unit 16A sequentially calculate the characteristic values at the reference operating point and the reference power point, thereby obtaining the desired unknown characteristic value as the output characteristic value 3 Calculate as

[Pump system]
Next, with reference to FIG. 2, a pump system to be processed by the pump characteristic value calculating 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 characteristic value calculation device.
The pump system 5 is a pump system for general air conditioning equipment provided in office buildings, public facilities, hotels, and the like. The pump system 5 has two systems of heat sources, and the primary and secondary pumps are provided in the heat source unit and the forward header, respectively. These pumps are provided with inverters 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. Further, the pressure difference between the forward headers 53A and 53B is adjusted to a predetermined pressure difference by controlling the opening degree of the valve 56 in accordance with the control from 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 speeds of the secondary pumps 54A, 54B, 54C are inverter-controlled so that the pressure difference between the forward headers 53A, 53B measured by the differential pressure gauge 55, that is, the head H becomes a predetermined pressure difference.

[Principle of calculation of pump characteristic value]
Next, with reference to FIG. 3 and FIG. 4, the principle of the pump characteristic value calculation in the pump characteristic value calculation apparatus 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 characteristic value calculation process]
As described in the principle of calculating the pump characteristic value shown in FIG. 3, when the control operating point R ₁ or the reference operating point R ₀ is specified, the resistance curve C corresponding to the load resistance related to the pump at that time is specified. can do. Thereby, when the control operation point R ₁ is known, the reference operation point R ₀ corresponding to the control operation point R ₁ can be specified based on the resistance curve C in a state where the load resistance is constant.
If any one of the reference operating point R ₀ , the control flow rate Q ₁ , the control lift H ₁ , and the control rotation speed ratio INV ₁ is known, the known characteristic value and the resistance curve C Based on the above, the control operation point R ₁ corresponding to the reference operation point R ₀ can be specified in a state where the load resistance is constant.

If the control power point P ₁ or the reference power point P ₀ is specified, the control time axis power curve B ₁ corresponding to the load resistance of the pump at that time can be specified. Thus, when the control power point P ₁ is known, the reference power point P ₀ corresponding to the control power point P ₁ can be specified based on the control time power curve B ₁ when the load resistance is constant. .
If any one of the reference power point P ₀ , the control flow rate Q ₁ , the control time shaft power E ₁ , and the control rotation speed ratio INV ₁ is known, this known characteristic value and the control time shaft Based on the power curve B ₁ , the control power point P ₁ corresponding to the reference power point P ₀ can be specified when the load resistance is constant.

At this time, as shown in FIG. 3, the reference flow rate Q ₀ at the reference operating point R ₀ and the reference power point P ₀ is the same, control when the flow rate Q ₁ at the control during operation point R ₁ and the control during power point P ₁ Are the same. For this reason, when the control operation point R ₁ is known, the resistance curve C → the reference operation point R ₀ → the reference flow rate Q ₀ → the reference power point P ₀ → the control time axis power curve B ₁ is specified in order, The control power point P ₁ can be specified.
Therefore, the control during the flow rate Q ₁ that identifies the control during operation point R _1, the control during lift H _1, when as any two of the input characteristic value 2 of the control when the rotational speed ratio INV ₁ known, the control during power point An unknown control time axis power E ₁ at P ₁ can be obtained.

On the other hand, when the control power point P ₁ is known, the control time power curve B ₁ → the reference power point P ₀ → the reference flow rate Q ₀ → the reference operating point R ₀ → the resistance curve C in this order. By specifying, the control operating point R ₁ can be specified.
Therefore, the control during shaft power E ₁ which identifies the control during power point P _1, 2 one characteristic values consisting of and either control when the flow rate Q ₁ or control when the rotational speed ratio INV ₁ are known, the input characteristic value 2 Can be obtained as an unknown control head H ₁ at the control operating point R ₁ .

[Configuration of pump characteristic value calculation device]
Next, the configuration of the pump characteristic value calculation apparatus 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, at least any two of the flow rate Q, the head H, the shaft power E, and the rotational speed ratio INV related to the pump that is the target of the characteristic value calculation is 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 is acquired as the flow rate Q, the differential pressure measured by the differential pressure meter 55 is acquired as the head H, and the secondary pump The shaft power obtained from the power consumption measured by the wattmeters (not shown) of 54A, 54B and 54C is obtained, and the control rotation speed ratio INV ₁ measured by the secondary pumps 54A, 54B and 54C is obtained. That's fine. When the rotation speed can be obtained from the secondary pumps 54A, 54B, 54C and the secondary pump control device 50B, the calculation processing unit 16 may convert the rotation speed into a rotation speed ratio at the time of data acquisition. Alternatively, the data acquisition unit 11 may directly acquire the power consumption from the pump system, and calculate the shaft power from the product of the preset pump motor efficiency and inverter efficiency and power consumption.

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 a pump characteristic value calculation process by the 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 calculation result of a pump characteristic value on the screen in accordance with an output from the arithmetic processing unit 16. ing.
The data output unit 14 includes a dedicated data communication circuit, and has a function of outputting the output characteristic 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 characteristic value 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 characteristic value calculation processing, and is stored in advance from an external device or a recording medium via the data acquisition unit 11. 15 is stored.
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, and a function shape equation 15C.

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 arithmetic processing unit 16 has 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 to calculate the pump characteristic value. It has a function of realizing various processing units necessary for processing.
As main processing units realized by the arithmetic processing unit 16, there are a reference operating point specifying unit 16A, a reference power point specifying unit 16B, and a characteristic value calculating unit 16C.

The reference operating point specifying unit 16A is based on an arbitrary characteristic value, a resistance curve indicating the relationship between the pump flow rate and the head when the pump rotation speed is controlled in a state where the pump piping resistance is constant, and the storage unit 15 It has a function of calculating a reference flow rate or a reference lift of the pump when operating at a reference rotational speed by specifying a reference operating point that is an intersection with the reference lift curve.
The reference power point specifying unit 16B has a control time axis power curve indicating the relationship between the pump flow rate and the shaft power when the pump rotation speed is controlled in a state where the pump piping resistance is constant based on an arbitrary characteristic value. By specifying a reference power point that is an intersection with the reference shaft power curve in the storage unit 15, the pump has a function of calculating the reference flow rate or reference shaft power of the pump when operating at the reference rotation speed.

Based on the input characteristic value 2 acquired by the data acquisition unit 11, the characteristic value calculation unit 16C performs the characteristics at the reference operation point R ₀ and the reference power point P ₀ by the reference operation point specification unit 16A and the reference operation point specification unit 16A. A function for sequentially calculating values, a function for calculating an unknown characteristic value desired based on these characteristic values as an output characteristic value 3, and a screen display unit 13 for displaying the calculated output characteristic value 3 or a data output unit 14 to output to an external device such as the pump system 5.

[Operation of First Embodiment]
Next, the operation of the pump characteristic value calculation apparatus according to the first embodiment of the present invention will be described.
The pump characteristic value calculating device 1 is a pump that is variably controlled at an arbitrary control rotation speed in the pump system 5. Among the plurality of characteristic values that indicate the operation status of the pump, From the value 2, an unknown characteristic value is calculated as an output characteristic value 3. At this time, whether the control time axis power E ₁ is the output characteristic value 3 or the input characteristic value 2, that is, the control time axis power E ₁ is calculated from another characteristic value or another characteristic value is calculated from the control time axis power E _1. Depending on whether or not the pump characteristic value calculation process can be roughly divided.

[When the control shaft power is an output characteristic value]
First, with reference to FIG. 5 to FIG. 8, a pump characteristic value calculation process when the control-time shaft power is an output characteristic value will be described. FIG. 5 is a flowchart showing a pump characteristic value calculation process (when the control time shaft power is an output characteristic value) of the pump characteristic value calculating apparatus according to the first embodiment of the present invention. FIG. 6 is a flowchart showing a pump characteristic value calculation process (when the control time shaft power is an output characteristic value) of the pump characteristic value calculating apparatus according to the first embodiment of the present invention. FIG. 7 is a flowchart showing a reference operating point specifying process in the pump characteristic value calculating process of FIG. FIG. 8 is a flowchart showing a reference power point specifying process in the pump characteristic value calculating process of FIG.

The arithmetic processing unit 16 of the pump characteristic value calculating device 1 performs the pump of FIG. 5 and FIG. 6 by the characteristic value calculating unit 16C in response to the start instruction operation of the pump characteristic value calculating process detected by the operator by the operation input unit 12. The characteristic value calculation process is started.
When the control shaft power is the output characteristic value 3, any two of the control flow rate Q ₁ , control lift H ₁ , and control rotation speed ratio INV ₁ at the control operation point R ₁ in FIG. The characteristic value is 2. Here, a case where the control time shaft power E ₁ is calculated with the control flow rate Q ₁ and the control lift H ₁ as the input characteristic value 2 will be described as an example.

The characteristic value 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 characteristic value calculation unit 16C performs reference operation point specification processing of FIG. 7 described later by the reference operation point specification unit 16A to calculate a reference flow rate Q ₀ (step 101).
Subsequently, the characteristic value calculation unit 16C performs a reference power point specifying process of FIG. 8 described later by the reference power point specifying unit 16B to calculate a reference shaft power E ₀ (step 102).

Thereafter, the characteristic value calculation unit 16C reads the reference flow rate Q ₀ calculated by the reference operating point specifying unit 16A and the reference shaft power E ₀ calculated by the reference power point specifying 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 a constant is obtained from the reference flow rate Q ₀ and the reference shaft power E _0. β is calculated (step 105). Thus, the control time axis power curve B ₁ is specified.

Then, the characteristic value calculating 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), controlled from the control when the flow rate Q ₁ and the control when the shaft power curve B ₁ Metropolitan The time axis power E ₁ is calculated (step 107). Thus, the identified control during power point P ₁ on the control when the shaft power curve B _1, the control during the shaft power E ₁ temporarily stored in the storage unit 15 (step 108), a series of pump specific value calculation process finish.

[Standard operation point identification process]
The reference operating point specifying unit 16A starts the reference operating point specifying process of FIG. 7 in response to an instruction from the characteristic value calculating unit 16C.
First, the reference operating point specifying unit 16A reads the control flow rate Q ₁ and the control lift H ₁ indicating the control operating point R ₁ from the storage unit 15 (step 110), and from the function shape formula 15C of the storage unit 15 reads the formula (3) described above as a function shape type resistance curve C (step 111), calculates the constants α from the control when the flow rate Q ₁ and control during lift H ₁ (step 112). Thereby, the resistance curve C is specified.

Subsequently, the reference operating point specifying 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 113). By solving the lift 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 (step) 114). Then, the obtained reference flow rate Q ₀ is temporarily stored in the storage unit 15 (step 115), and the series of reference operating point specifying processes is terminated.

[Reference power point identification processing]
The reference power point specifying unit 16B starts the reference power point specifying process of FIG. 8 in response to an instruction from the characteristic value calculating unit 16C.
First, the reference power point specifying unit 16B reads the reference flow rate Q ₀ from the storage unit 15 (step 120), and the reference in which the constant of the formula (7) is fixed 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 121).
Subsequently, the reference power point specifying unit 16B calculates the reference shaft power E ₀ from the reference flow rate Q ₀ and the reference shaft power curve B ₀ (step 122). Thereby, the intersection of the reference shaft power curve B ₀ and the control time shaft power curve B ₁ , that is, the reference power point P ₀ is specified, and this reference shaft power E ₀ is temporarily stored in the storage unit 15 (step 123). A series of reference power point specifying processes are terminated.

[When the control time shaft power is included in the input characteristic value]
First, with reference to FIGS. 9 to 12, a pump characteristic value calculation process when the control time shaft power is included in the input characteristic value will be described. FIG. 9 is a flowchart showing a pump characteristic value calculation process (when control-time shaft power is included in the input characteristic value) of the pump characteristic value calculating apparatus according to the first embodiment of the present invention. FIG. 10 is a flowchart showing a pump characteristic value calculation process (when control-time shaft power is included in the input characteristic value) of the pump characteristic value calculating apparatus according to the first embodiment of the present invention. FIG. 11 is a flowchart showing a reference operating point specifying process in the pump characteristic value calculating process of FIG. FIG. 12 is a flowchart showing a reference power point specifying process in the pump characteristic value calculating process of FIG.

The arithmetic processing unit 16 of the pump characteristic value calculating device 1 performs the pump of FIG. 9 and FIG. 10 by the characteristic value calculating unit 16C according to the start instruction operation of the pump characteristic value calculating process detected by the operator by the operation input unit 12. The characteristic value calculation process is started.
When the control shaft power is included in the input characteristic value 2, any _one of the control flow rate Q ₁ , the control lift H ₁ , and the control rotation speed ratio INV ₁ at the control operation point R ₁ in FIG. One is the input characteristic value 2. Here, a case where the control lift H ₁ is calculated using the control flow rate Q ₁ and the control shaft power E ₁ as the input characteristic value 2 will be described as an example.

The characteristic value calculation unit 16C first acquires the control flow rate Q ₁ and the control time shaft power E 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. Save (step 150).
Subsequently, the characteristic value calculation unit 16C performs a reference power point specifying process of FIG. 11 described later by the reference power point specifying unit 16B to calculate a reference flow rate Q ₀ (step 151).
Next, the characteristic value calculation unit 16C performs a reference operation point specification process of FIG. 11 described later by the reference operation point specification unit 16A to calculate a reference head H ₀ (step 152).

Thereafter, the characteristic value calculation unit 16C reads the reference flow rate Q ₀ calculated by the reference power point specifying unit 16B and the reference head H ₀ calculated by the reference operating point specifying unit 16A from the storage unit 15 (step S1). 153), the above-described equation (3) is read out from the function shape equation 15C of the storage unit 15 as the function shape equation of the resistance curve C (step 154), and the constant α is calculated from the reference flow rate Q ₀ and the reference head H ₀ (step 154). 155). Thereby, the resistance curve C is specified.

Subsequently, the characteristic value calculation unit 16C reads the control flow rate Q ₁ at the control operation point R ₁ from the storage unit 15 (step 156), and the control time shaft power E from the control flow rate Q ₁ and the resistance curve C. ₁ is calculated (step 157). Thus, the control time is controlled during the lift H ₁ on shaft power curve B ₁ is calculated, the control during lift H ₁ temporarily stored in the storage unit 15 (step 158), and ends the series of pump specific value calculation process .

[Reference power point identification processing]
The reference power point specifying unit 16B starts the reference power point specifying process of FIG. 11 in response to an instruction from the characteristic value calculating unit 16C.
First, the reference power point specifying unit 16B reads the control-time flow rate Q1 indicating the control-time power point P1 and the control-time shaft power E1 from the storage unit 15 (step 160), and at the time of control from the function shape formula 15C of the storage unit 15 The above-described equation (8) is read as a function shape equation of the shaft power curve B1 (step 161), and a constant β is calculated from the control flow rate Q1 and the control lift H1 (step 162). Thereby, the control time axis power curve B1 is specified.

  Next, the reference power point specifying unit 16B reads the reference shaft power curve function formula 15B in which the constant of the formula (7) is fixed as the reference shaft power curve B0 from the storage unit 15 (step 163). By solving the shaft power curve B1 and the reference shaft power curve B0 as simultaneous equations, the reference flow rate Q0 and the reference shaft power E0 at the intersection of the control time shaft power curve B1 and the reference shaft power curve B0 are calculated (step 164). The reference flow rate Q0 and the reference shaft power E0 are temporarily stored in the storage unit 15 as the reference power point P0 (step 165), and the series of reference power point specifying processes is terminated.

[Standard operation point identification process]
The reference operating point specifying unit 16A starts the reference operating point specifying process of FIG. 12 in response to an instruction from the characteristic value calculating unit 16C.
First, the reference operating point specifying unit 16A reads the reference flow rate Q0 of the reference power point P0 from the storage unit 15 (step 170), and the constant of the above-described formula (2) is determined as the reference lift curve A0 from the storage unit 15. The reference lift curve function formula 15A is read (step 171). Then, the reference lift H0 is calculated from the reference flow rate Q0 and the reference lift curve A0 (step 172), and the obtained reference lift H0 is temporarily stored in the storage unit 15 as the reference operating point R0 together with the reference flow rate Q0 (step 173). Then, the series of reference operating point specifying processes is terminated.

[Effect of the first embodiment]
As described above, the present embodiment allows the arithmetic processing unit 16 to determine the relationship between the pump flow rate and the head when the pump rotation speed is controlled in a state where the pump piping resistance is constant based on an arbitrary characteristic value. By specifying a reference operating point R ₀ consisting of the intersection of the resistance curve C shown and the reference lift curve A ₀ of the storage unit 15, the reference flow rate Q ₀ or the reference lift H ₀ of the pump when operating at the reference rotation speed is obtained. Based on the calculated reference operating point specifying unit 16A and an arbitrary characteristic value, the control time axis power indicating the relationship between the pump flow rate and the shaft power when the pump rotational speed is controlled with the pump piping resistance being constant. By specifying a reference power point P ₀ consisting of the intersection of the curve B ₁ and the reference shaft power curve B ₀ of the storage unit 15, the reference flow rate Q ₀ of the pump or the reference shaft power when operating at the rated rotational speed N ₀ is specified. reference power point specifying unit 16 to calculate the E ₀ It is provided with a door.

Then, in the characteristic value calculation unit 16C of the arithmetic processing unit 16, based on the input characteristic value 2, the characteristic values at the reference operation point R ₀ and the reference power point P ₀ are obtained by the reference operation point specifying unit 16A and the reference operation point specifying unit 16A. The desired unknown characteristic value is calculated as the output characteristic value 3 by sequentially calculating.

Specifically, when the control-time shaft power E ₁ is the output characteristic value 3, the data acquisition unit 11 causes the control-time flow rate Q ₁ , the control-time head H ₁ , and the control-time rotation speed ratio INV ₁ to be selected. get any two as the input characteristic value 2, the reference operating point specifying unit 16A, and calculates the reference flow rate Q ₀ at the reference operating point R ₀ on the basis of the input characteristic value 2 obtained by the data acquisition unit 11, The reference power point specifying unit 16B calculates the reference shaft power E ₀ at the reference power point P ₀ based on the reference flow rate Q ₀ , and the characteristic value calculating unit 16C calculates from the reference flow rate Q ₀ and the reference shaft power E _0. The control time axis power curve B ₁ is specified based on the reference power point P ₀ and the control time axis power curve function shape formula 15C, and the control time axis is determined from the control flow rate Q ₁ and the control time axis power curve B _1. The power E ₁ is calculated as an output characteristic value 3.

Further, when the control time shaft power E ₁ is the input characteristic value 2, the data acquisition unit 11 acquires the control time flow rate Q ₁ and the control time shaft power E ₁ as the input characteristic value 2 and specifies the reference power point. the section 16B, the reference flow rate Q ₀ of the reference power point P ₀ on the basis of the function-shaped type 15C of the control when the flow rate Q ₁ and the control time control during power point P ₁ consisting of shaft power E ₁ control during shaft power curve The reference operating point specifying unit 16A calculates the reference lift H ₀ at the reference operating point R ₀ based on the reference flow rate Q ₀ , and the characteristic value calculating unit 16C calculates the reference flow rate Q ₀ and the reference lift H _A resistance curve C is specified based on the reference operating point R ₀ consisting of ₀ and the function shape formula 15C of the resistance curve, and the control head H ₁ or the control rotation speed ratio is determined from the resistance curve C and the control flow rate Q _1. INV ₁ is calculated as an output characteristic value 3.

Therefore, 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 pump operating characteristic data 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.

In this embodiment, the case where the input characteristic value 2 is the control flow rate Q ₁ and the control lift H ₁ has been described as an example. However, the input characteristic value 2 is the control flow rate Q ₁ and the control rotation speed ratio INV. _In the case of ₁ , the control-time shaft power E ₁ can be calculated in the same manner as described above. In this case, when calculating the reference flow rate Q ₀ at the reference operating point R ₀ in step 101 of FIG. 6, the above-described formula (6) is calculated from the control flow rate Q ₁ and the control rotation speed ratio INV _{1 as} the input characteristic value 2. Can be used to calculate the reference flow rate Q ₀ . In the pump characteristic value calculation process in this case, the reference operating point R ₀ → reference flow rate Q ₀ → reference power point P ₀ → control time axis power curve B ₁ → control time power point P ₁ is not used without using the resistance curve C. It will be specified in order.

Similarly, when the input characteristic value 2 is the control lift H ₁ and the control rotation speed ratio INV ₁ , when calculating the reference flow rate Q ₀ at the reference operating point R ₀ in step 101 of FIG. The control lift H ₁ and the control rotation speed ratio INV ₁ are used to calculate the reference lift H ₀ using the above-described equation (6), and the reference lift H ₀ and the reference lift curve A ₀ of the storage unit 15 are used as the reference. The flow rate Q ₀ may be calculated. Even in the pump characteristic value calculation process in this case, the reference operating point R ₀ → the reference flow rate Q ₀ → the reference power point P ₀ → the control time shaft power curve B ₁ → the control time power point P ₁ is not used without using the resistance curve C. It will be specified in order.

Further, in the present embodiment, the case where the control lift H ₁ is calculated using the control flow rate Q ₁ and the control shaft power E ₁ as the input characteristic value 2 has been described as an example, but the same input characteristic value 2 the case of calculating the control when the rotational speed ratio INV ₁ with, it is possible to calculate the control time shaft power E ₁ in the same manner as described above. In this case, in step 157 of FIG. 10, the control rotation speed ratio INV ₁ may be calculated from the reference lift H ₀ and the control lift H ₁ using the above-described equation (5). In the pump characteristic value calculation process in this case, the control time axis power curve B ₁ → the reference power point P ₀ → the reference flow rate Q ₀ → the reference operation point R ₀ → the resistance curve C → the control operation point R ₁ is specified in order. It will be.

[Second Embodiment]
Next, with reference to FIG. 13, a pump characteristic value calculating apparatus according to a second embodiment of the present invention will be described. FIG. 13 is a flowchart showing a pump characteristic value calculation process of the pump characteristic value calculation apparatus according to the second embodiment of the present invention.

In the first embodiment, when the control-time shaft power E ₁ is included in the input characteristic value 2, the control-time flow rate Q ₁ is the other input characteristic value 2, and the control-time head H ₁ or the control-time rotation speed ratio. The case where INV ₁ is calculated as the output characteristic value 3 has been described as an example. In the present embodiment, when the control-time shaft power E ₁ is included in the input characteristic value 2, _one of the characteristic values of the control lift H ₁ or the control rotation speed ratio INV ₁ is the other input characteristic value 2. The case where the other characteristic value is calculated as the output characteristic value 3 will be described.

When one of the two input characteristic values 2 is the control-time shaft power E ₁ and the other is either the control-time lift H ₁ or the control-time rotational speed ratio INV ₁ , Both the operating point R ₁ and the control power point P ₁ cannot be specified. For this reason, in the present embodiment, the characteristic value calculation unit 16C of the arithmetic processing unit 16 assumes a characteristic value of either the control lift H ₁ or the control rotation speed ratio INV _{1 as} the output characteristic value 3. And a function for comparing the output characteristic value 3 calculated based on the assumed characteristic value with the original assumed characteristic value and outputting the assumed characteristic value as the output characteristic value 3 based on the comparison result. Other configurations of the pump characteristic value calculating apparatus according to the present embodiment are the same as those in the first embodiment, and detailed description thereof is omitted here.

[Operation of Second Embodiment]
Next, with reference to FIG. 13, a pump characteristic value calculation process according to the second embodiment of the present invention will be described.
The arithmetic processing unit 16 of the pump characteristic value calculating device 1 calculates the pump characteristic value shown in FIG. 13 by the characteristic value calculating unit 16C in response to the start instruction operation of the pump characteristic value calculating process detected by the operator by the operation input unit 12. Start processing.

When the control-time shaft power E ₁ is included in the input characteristic value 2, any _one of the control-time flow rate Q ₁ , the control-time head H ₁ , and the control-time rotation speed ratio INV ₁ at the control-time operating point R ₁ in FIG. One of them is the input characteristic value 2. Here, a case where the control lift H ₁ is calculated using the control rotation speed ratio INV ₁ and the control shaft power E ₁ as the input characteristic value 2 will be described as an example. Therefore, in the pump characteristic value calculation process in the present embodiment, the control head H ₁ assumption → the reference operating point R ₀ → the reference flow rate Q ₀ → the reference power point P ₀ → the control time shaft power curve B ₁ → the control flow rate Q ₁ → Resistance curve C → Verification control head H ₁ ′ is specified in order.

The characteristic value calculation unit 16C first acquires the control rotation speed ratio INV ₁ and the control time shaft power E ₁ of the control operation point R ₁ from the pump system 5 via the data acquisition unit 11, and sends them to the storage unit 15. Temporarily save (step 200).
Next, the characteristic value calculation unit 16C assumes a control head H ₁ and temporarily stores it in the storage unit 15 (step 201). At this time, a possible value of the control lift H ₁ is determined in advance as an assumed range, and the characteristic value of the control lift H ₁ may be assumed at predetermined intervals in order from the upper limit or the lower limit of the assumed range.

Subsequently, the characteristic value calculation unit 16C specifies the reference power point by the reference operating point specifying unit 16A based on the control rotation speed ratio INV ₁ that is the input characteristic value 2 and the control lift H ₁ that is the assumed characteristic value. The process is executed to calculate the reference flow rate Q ₀ (step 202). At this time, the control operating point R ₁ and the resistance curve C cannot be specified directly from the control rotation speed ratio INV ₁ as the input characteristic value 2 and the control lift H _{1 as the} assumed characteristic value. For this reason, for example, based on the above formula (5), the reference lift H ₀ is calculated from the control lift H ₁ and the control rotation speed ratio INV ₁ , and the reference lift curve is read from the reference lift H ₀ and the storage unit 15. The reference flow rate Q ₀ may be calculated from the reference head curve A ₀ of the function formula 15A.

Next, the characteristic value calculating unit 16C based on the reference flow Q ₀ calculated at the reference operating point specifying unit 16A, in the same manner as described above by reference power point specifying unit 16B to perform a reference power point specifying processing in FIG. 8 A reference shaft power E ₀ is calculated (step 203).
Then, the characteristic value calculating unit 16C, as in step 103 to step 105 of FIG. 6 described above, the reference power point P ₀ consisting reference flow rate Q ₀ and the reference axis power E ₀ of the control when the shaft power curve B ₁ From the function shape formula, the control time axis power curve B ₁ is specified (step 204), and from this control time axis power curve B ₁ and the control time axis power E _{1 of} the input characteristic value 2 read from the storage unit 15, The control flow rate Q ₁ at the control power point P ₁ is calculated and temporarily stored in the storage unit 15 (step 205).

Next, the characteristic value calculation unit 16C reads the reference flow rate Q ₀ and the reference lift H ₀ at the reference operating point R ₀ from the storage unit 15, and uses the function shape equation 15C of the storage unit 15 as the function shape equation of the resistance curve C. The above-described equation (3) is read, a constant α is calculated from the reference flow rate Q ₀ and the reference lift H ₀ , and the resistance curve C is specified (step 206).
Subsequently, the characteristic value calculation unit 16C calculates the verification control lift H1 ′ based on the resistance curve C and the control flow rate Q ₁ at the control power point P ₁ read from the storage unit 15 (step S1). 207).

Here, characteristic value calculating unit 16C compares the control during lift H ₁ is assumed characteristic value verification control during lift H1 '(step 208), within a predetermined tolerance of both the error is set in advance If it is not (step 208: nO), returns to step 201 only shift characteristic value predetermined distance from the current assumptions characteristic value newly assumed as hypothetical characteristic value of the control time of lift H _1, repeat steps 202 to 207 Run.
On the other hand, when the error between the two is within a predetermined allowable range set in advance (step 208: YES), the characteristic value calculation unit 16C sets the control head H ₁ that is the assumed characteristic value as the output characteristic value 3. Temporary storage is performed in the storage unit 15 (step 209), and the series of pump specific value calculation processing ends.

[Effect of the second embodiment]
As described above, in the present embodiment, the data acquisition unit 11 acquires the control rotation speed ratio INV ₁ and the control time shaft power E ₁ as the input characteristic value 2, and the characteristic value calculation unit 16C performs control. Assuming that the hourly head H ₁ is an assumed characteristic value, the reference operating point specifying unit 16A determines the reference of the pump at the reference operating point R ₀ based on the control-time rotational speed ratio INV ₁ and the assumed characteristic value of the control-time head H _1. The flow rate Q ₀ is calculated, and the reference power point specifying unit 16B calculates the reference shaft power E ₀ of the pump at the reference power point P ₀ based on the reference flow rate Q ₀ .

Then, the characteristic value calculating unit 16C, the reference flow rate Q ₀ and the reference axis shaft power curve when control of the pump on the basis of the function-shaped type 15C of the reference power point P ₀ and the control when the shaft power curve consisting of the power E ₀ B ₁ The control flow rate Q ₁ is calculated based on the control time axis power curve B ₁ and the control time axis power E _1, and specified based on the reference operating point R ₀ and the function shape formula 15C of the resistance curve. The control control head H ₁ ′ corresponding to the assumed characteristic value is calculated from the resistance curve C of the pump and the control flow rate Q ₁ , and the comparison result between the control control head H ₁ ′ and the assumed characteristic value is calculated. Accordingly, the assumed characteristic value is calculated as the output characteristic value 3.

As a result, when both the control operating point R ₁ and the control power point P ₁ cannot be specified from the input characteristic value 2, specifically, one of the two input characteristic values 2 is the control time shaft power E. ₁ and the other is the characteristic value of either the control lift H ₁ or the control rotation speed ratio INV ₁ , the desired characteristic value, here the control lift H ₁ or the control rotation speed ratio. The other characteristic value of INV ₁ can be calculated.

In this embodiment, the case where the input characteristic value 2 is the control rotation speed ratio INV ₁ and the control shaft power E ₁ has been described as an example. However, the input characteristic value 2 is the control lift H ₁ and the control time shaft. In the case of the power E ₁ as well, the control rotation speed ratio INV ₁ can be calculated in the same manner as described above. In this case, assuming the control when the rotational speed ratio INV ₁ in step 201 of FIG. 13, comparing the assumed characteristic value a is controlled when the rotational speed ratio INV ₁ and the verification control when the rotational speed ratio INV ₁ 'in step 208 become.

Further, in steps 206 and 207, for example, the verification control rotational speed ratio INV ₁ ′ may be calculated from the control lift H ₁ and the reference lift H ₀ that are the input characteristic value 2 based on the above-described equation (5). . Accordingly, in the pump characteristic value calculation process in this case, the control rotation speed ratio INV _{1 is} assumed → the reference operating point R ₀ → the reference flow rate Q ₀ → the reference power point P ₀ → the control time shaft power curve B ₁ → the control flow rate Q ₁ → The rotational speed ratio INV ₁ ′ during verification control is specified in order.

[Third Embodiment]
Next, with reference to FIG. 14, a pump characteristic value calculation apparatus according to a third embodiment of the present invention will be described. FIG. 14 is a flowchart showing a pump characteristic value calculating process of the pump characteristic value calculating apparatus according to the third embodiment of the present invention.

In the second embodiment, when the control-time shaft power E ₁ is included in the input characteristic value 2, _one of the characteristic values of the control-time lift H ₁ or the control-time rotation speed ratio INV ₁ is the other input characteristic. The case where the other characteristic value is calculated as the output characteristic value 3 with the value 2 has been described as an example. In the present embodiment, when the control-time shaft power E ₁ is included in the input characteristic value 2, _one of the characteristic values of the control lift H ₁ or the control rotation speed ratio INV ₁ is the other input characteristic value 2. The case where the control flow rate Q ₁ is calculated as the output characteristic value 3 will be described.

When one of the two input characteristic values 2 is the control-time shaft power E ₁ and the other is either the control-time lift H ₁ or the control-time rotational speed ratio INV ₁ , Both the operating point R ₁ and the control power point P ₁ cannot be specified. Therefore, in the present embodiment, the computing the characteristic value calculating unit 16C of the processing unit 16, a characteristic value assumes the function of the control when the flow rate Q ₁ as an output characteristic value 3, the output calculated on the basis of this assumption characteristic value A function for comparing the characteristic value 3 with the original assumed characteristic value and outputting the assumed characteristic value as the output characteristic value 3 based on the comparison result is provided. Other configurations of the pump characteristic value calculating apparatus according to the present embodiment are the same as those in the first embodiment, and detailed description thereof is omitted here.

[Operation of Third Embodiment]
Next, pump characteristic value calculation processing according to the third embodiment of the present invention will be described with reference to FIG.
The arithmetic processing unit 16 of the pump characteristic value calculating device 1 calculates the pump characteristic value shown in FIG. 14 by the characteristic value calculating unit 16C in response to the start instruction operation of the pump characteristic value calculating process detected by the operator by the operation input unit 12. Start processing.

When the control-time shaft power E ₁ is included in the input characteristic value 2, any _one of the control-time flow rate Q ₁ , the control-time head H ₁ , and the control-time rotation speed ratio INV ₁ at the control-time operating point R ₁ in FIG. One of them is the input characteristic value 2. Here, a case where the control flow rate Q ₁ is calculated using the control lift H ₁ and the control shaft power E ₁ as the input characteristic value 2 will be described as an example. Therefore, in the pump characteristic value calculation process in the present embodiment, the control flow rate Q _{1 is} assumed → the control time axis power curve B ₁ → the reference power point P ₀ → the reference flow rate Q ₀ → the reference operating point R ₀ → the resistance curve C → The verification control flow rate Q ₁ ′ is specified in order.

The characteristic value calculation unit 16C first acquires the control head H ₁ and the control time shaft power E ₁ of 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 300).
Next, the characteristic value calculating unit 16C assumes control when the flow rate Q _1, is temporarily stored in the storage unit 15 (step 301). At this time, a possible value of the control flow rate Q ₁ is determined in advance as an assumed range, and the characteristic value of the control flow rate Q ₁ is assumed at predetermined intervals in order from the upper limit or the lower limit of the assumed range.

Subsequently, the characteristic value calculation unit 16C calculates the reference power point based on the control time power point P ₁ specified from the control time axis power E ₁ that is the input characteristic value 2 and the control time flow rate Q ₁ that is the assumed characteristic value. run the reference power point specifying processing in Fig. 12 in the same manner as described above to calculate the reference flow rate Q ₀ by a specific unit 16B (step 302).
Next, the characteristic value calculating unit 16C based on the reference flow Q ₀ calculated by the reference power point specifying unit 16B, the reference operating point specifying unit 16A running reference operating point specifying process described above as well as FIG. 11 A reference head H ₀ is calculated (step 304).

Next, the characteristic value calculation unit 16C reads the reference flow rate Q ₀ and the reference lift H ₀ at the reference operating point R ₀ from the storage unit 15, and uses the function shape equation 15C of the storage unit 15 as the function shape equation of the resistance curve C. The above-described equation (3) is read, a constant α is calculated from the reference flow rate Q ₀ and the reference lift H ₀ , and the resistance curve C is specified (step 304).
Subsequently, the characteristic value calculation unit 16C, based on the resistance curve C and the control head H ₁ at the control operation point R ₁ that is the input characteristic value 2 read from the storage unit 15, controls the control flow rate Q for verification. ₁ 'is calculated (step 305).

Here, the characteristic value calculation unit 16C compares the control flow rate Q ₁ which is an assumed characteristic value with the verification control flow rate Q ₁ ′ (step 306), and a predetermined allowable range in which an error between the two is set in advance. If it is not within (step 306: nO), it returns to step 301 only shift characteristic value predetermined distance from the current assumptions characteristic value newly assumed as hypothetical characteristic value of the control when the flow rate Q _1, the steps 302 to 305 Run repeatedly.
On the other hand, when the error between the two is within a predetermined allowable range set in advance (step 306: YES), the characteristic value calculation unit 16C sets the assumed control characteristic head H ₁ as the output characteristic value 3 as the assumed characteristic value. Temporary storage is performed in the storage unit 15 (step 307), and the series of pump specific value calculation processing ends.

[Effect of the third embodiment]
As described above, in the present embodiment, the data obtaining unit 11 obtains the control-time head H ₁ and the control-time shaft power E ₁ related to the pump as the input characteristic value 2, and the characteristic value calculation unit 16C obtains the control-time flow rate. assuming Q ₁ as assuming characteristic values, the reference power point specifying unit 16B, a control during shaft power E ₁ and control when the flow rate Q ₁ control during power point P ₁ consisting of a function-shaped type 15C control during shaft power curve identify control during shaft power curve B ₁ of the pump based on, and calculates the reference flow rate Q ₀ of the reference power point P ₀ from the intersection of the control when the shaft power curve B ₁ and the reference axis power curve B ₀ .

Then, the reference operating point specifying unit 16A calculates the reference lift H ₀ based on the reference flow rate Q ₀ and the reference lift curve A ₀ , and the characteristic value calculation unit 16C includes the reference flow rate Q ₀ and the reference shaft power E _0. A resistance curve C is specified based on the reference operating point R ₀ and the function shape formula 15C of the resistance curve, and the verification control flow rate Q ₁ ′ corresponding to the assumed characteristic value from the resistance curve C and the control head H _1. And the assumed characteristic value is calculated as the output characteristic value 3 according to the comparison result between the verification control flow rate Q ₁ ′ and the assumed characteristic value.

As a result, when both the control operating point R ₁ and the control power point P ₁ cannot be specified from the input characteristic value 2, specifically, one of the two input characteristic values 2 is the control time shaft power E. ₁ and the other is the characteristic value of either the control head H ₁ or the control speed ratio INV ₁ , the desired characteristic value, here, the control flow rate Q ₁ can be calculated. .

In the present embodiment, the case where the input characteristic value 2 is the control head H ₁ and the control shaft power E ₁ has been described as an example. However, the input characteristic value 2 is the control rotation speed ratio INV ₁ and the control time shaft. in the case of the power E _1, it is possible to calculate the control time flow rate Q ₁ in the same manner as described above. In this case, since the control during lift H ₁ is unknown, in step 304 and 305 of FIG. 14, based on the equation (6) described above from the reference lift H ₀ and the control when the rotational speed ratio INV ₁ Tokyo, during verification control The flow rate Q ₁ ′ may be calculated. Therefore, in the pump characteristic value calculation process in this case, the control flow rate Q _{1 is} assumed → the control time axis power curve B ₁ → the reference power point P ₀ → the reference flow rate Q ₀ → the reference operating point R ₀ → the control control flow rate Q ₁ 'will be specified in turn.

[Extended embodiment]
In each of the above-described embodiments, the example in which the desired unknown output characteristic value 3 is calculated using each formula described in the principle of the pump characteristic value calculation has been described. It is not limited to the example. For example, when specifying the reference operation point R ₀ from the control operation point R _1, there are a method using the resistance curve C and a method using the control rotation speed ratio INV ₁ . Therefore, when 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 case has been described as an example in which a desired characteristic value is calculated using two known characteristic values as the input characteristic value 2, but three known characteristic values are used as the input characteristic value 2. Even when a desired characteristic value is calculated, each embodiment of the present invention can be applied, and similar effects can be obtained.

  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 air conditioning equipment that sends heat source water to an external load with a secondary pump, for example, a system that blows air with a fan, and the same 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. Further, the obtained output characteristic value 3 may be output from the data output unit 14 to a personal computer or a storage medium.

DESCRIPTION OF SYMBOLS 1 ... Pump characteristic value 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, 15P ... program, 16 ... calculation processing section, 16A ... reference operating point identification section, 16B ... reference power point identification section, 16C ... characteristic value calculation section, 2 ... input characteristic value, 3 ... Output characteristic 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, 61, 62 ... heat source pipe Road, 3 ...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 during lift , H ₁ ′ ··· Control head for verification, 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 ··· during control Rotational speed ratio, INV ₁ '... Vertical speed ratio for control, A ₀ ... Reference lift curve, A ₁ ... Control lift curve, B ₀ ... Reference axis power curve, B ₁ ... Control time axis power curve, C ... Resistance curve, R ₀ ... Reference operating point, R ₁ ... Control operating point, P ₀ ... Reference power point, P ₁ ... Control power point.

Claims (1)

For a pump whose rotation speed N is variably controlled at an arbitrary control rotation speed N ₁ , an unknown characteristic value is output from a known input characteristic value among a plurality of characteristic values indicating the operation status of the pump. A pump characteristic value calculating device for calculating as a value,
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 storage unit for storing a control time axis power curve function shape formula approximating a control time axis power curve B ₁ indicating the relationship between the flow rate of the pump and the shaft power when controlling the rotational speed N of the pump;
A data acquisition unit 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;
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 operating point specific for calculating a reference flow rate Q ₀ in the reference operating point R ₀ And
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 Thus, a reference power point specifying unit for calculating the reference shaft power E ₀ at 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 pump characteristic value calculating device comprising: a characteristic value calculating unit that calculates the control-time shaft power E ₁ as the output characteristic value.

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