JPS6174015A - Automatic pressure control system - Google Patents

Abstract

PURPOSE:To make a flow/air quantity measuring device unnecessary, and to obtain an automatic pressure control system at a low cost by applying a signal for showing a present fluid carrying capacity of a pump, etc., as a feedback signal to a controller. CONSTITUTION:An automatic pressure control system of an air-conditioning system, etc. sends a fluid to a load through a carrying path 3 by a pump and an air blower 1. This pump 1, etc. are provided with a capacity controller 2 for changing a fluid carrying capacity, and also provided with a demand side capacity controller 4. Also, a controller 6 is provided, and by a pressure signal (a) of a pressure detector 5 provided on a fluid sending-out side of the pump 1, etc., and a capacity signal (manipulated variable feedback signal) (b) for showing a present flow rate carrying capacity from the capacity controller 2, the carrying capacity of the pump 1, etc. is controlled by a control signal (c) so that the pressure signal (a) coincides with the carrying capacity of the capacity signal (b), based on a target value setting in advance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is a method for transporting a fluid (for example, water or air) using a fluid conveyance device (for example, a fan or a blower) whose fluid conveyance capacity can be changed. , relates to an automatic pressure control method for automatically controlling the fluid pressure on the fluid delivery side of the fluid transport device to a predetermined target pressure in a system (for example, an air conditioning system) that supplies the fluid to a load via a transport path.

Specifically, in the air conditioning system as described above, when a pump or a blower whose conveyance capacity can be changed changes the conveyance amount depending on the demand side (load side) condition, the present invention can reduce the conveyance power or reduce the conveyance power. The present invention relates to an automatic pressure control scheme for varying fluid delivery pressure for the purpose of demand side optimization, or both.

[Conventional technology]

Conventionally, in this type of automatic pressure control system.

Installed on the fluid delivery side of a pump or blower.

A pressure detector for measuring fluid pressure, a flow rate or airflow meter CII device for measuring the amount conveyed by a pump or blower, and a pressure signal output from the pressure detector and the flow rate or airflow measurement device. and a regulator that receives a conveyance amount signal output from the pump or the blower and controls the conveying force of the pump or the blower.

The relationship between the amount of conveyance to be controlled and the delivery pressure of the pump or blower is preset in the regulator.

1. The cough regulator determines the target value of the delivery pressure from the set relationship based on the flow rate or the conveyance amount measured by the air volume measuring device, and sets the delivery pressure that is measured to this target value. Control the conveying capacity of the pump or blower to match.

[Problem that the invention attempts to solve]

As described above, the conventional control system requires a flow rate or air volume measuring device, and the problem is the price including the installation conditions and construction costs of this flow rate or air volume measuring device.

An object of the present invention is to provide an inexpensive automatic pressure control system that does not require a flow rate or air volume measuring device.

Means for Solving the Problems of Kinpaku C] According to the present invention, a fluid transport device whose fluid transport capacity can be changed is provided, and a fluid is transported by the fluid transport device.

In the system for sending the fluid to the load via the conveying path, the fluid delivery device is provided on the fluid delivery side of the fluid delivery device. comprising: a detector for measuring fluid pressure; and a regulator receiving a pressure signal output from the detector and a fluid conveying capacity signal indicating a current fluid conveying capacity from the fluid conveying device; A target value of the fluid pressure on the fluid delivery side of the fluid transport device for each fluid transport capacity is set in advance, and the regulator controls the pressure indicated by the pressure signal to control the forging force indicated by the fluid capacity signal. method is obtained.

〔Example〕

Referring to FIG. 1, an automatic pressure control system according to one embodiment of the present invention is applied to an air conditioning system in which a pump or blower 1 supplies fluid to a load (not shown) through a conveying path 3.

The bonder 0 or blower 1 is equipped with a pump/blower capacity controller 2 for changing IN, body transfer capacity.

As a bonder/blower capacity controller 2.

Specifically, a controller (inverter) for the rotation speed of the pump or blower 1, a controller with a throttle function, or the like is used. 4 is a demand side capacity controller.

Demand-side capacity controller 1 is 2 specifically, control ``VAV (t・ariable air volume)''.
, x=7 (variable air volume unit, g), etc. are used.

The control method according to this embodiment was applied to the fluid delivery side of the pump or blower 1. Pressure detector 5 and 1 for measuring fluid pressure. The pressure signal (■) output from the pressure detector 5 and the bond/blower capacity signal (manipulated amount feeder,
and a regulator 6 for receiving the signal)@.

The target value of the fluid pressure on the fluid delivery side of the bonder/blower 1 is set in advance for each fluid conveying capacity.

The regulator 6 controls the conveying capacity of the bonder/blower l using the control signal θ so that the pressure indicated by the pressure signal ■ matches the target pressure value corresponding to the conveying capacity indicated by the port/blow/air blower capacity signal @. do.

Next, the operation of the regulator 6 will be explained in detail with reference also to FIG. In FIG. 2, the delivery pressure target curve 10 is
Required pressure P at point (B) in the diagram. The pressure (i.e., P) at point (A) in Figure 1 required to maintain .

This is a curve showing the pressure obtained by adding the pressure loss of the conveyance path 3 to Characteristic curve 11, 1 at each capacity of blower/pon f1
The pressure corresponding to 2.13 is the intersection point 14.1 with the 2 curve 10.
5.16. This relationship is preset l- in the regulator 6 as a characteristic equation.

Here, when the seven-stem resistance curve 21 is at a certain load, the blower/pump characteristic curve 112 is operating at the operating point 14. From this point on, the load changes.

The demand-side capacity controller 4 operates and the system resistance curve changes to 2.
If it becomes 2, the operating point shifts to 23. Operating point 2
The pressure No. 3 is detected by the pressure detector 5 and inputted to the regulator 6 as a signal ■. On the other hand, the state of the capacity controller 2 (
In this case, the signal @) corresponding to the characteristic curve 11 is also input to the regulator 6, and one point to one point is set according to the preset characteristic equation.
4 pressure is calculated. Set the pressure at this point 1↓ as the target value.

The difference ΔP1 between the pressures at the actual operating points 2 and 3 is used as a deviation.

The regulator 6 sends a 1Iill signal 61 to the capacity controller 2.

Take action to reduce the deviation. As a result of this process, when the blower/bonde 1 has the capacity shown in the characteristic curve 13, the target pressure value at the 9 points 16 and the pressure at the actual operating point 2-1 are changed in the same way as described in the case of the characteristic curve II. (bii difference becomes koP2, which decreases compared to ∆Pl but still remains.Furthermore, when the control is continued, at the point where the deviation disappears, that is, at point 15, where the target pressure value and the actual operating pressure value match) The capacity becomes stable as shown in the blower/pop characteristic curve 12.

Actual control operations are always performed continuously in response to load fluctuations.

In order to clarify this control operation, Fig. 3 shows the control pro,
FIG. 4 shows a flowchart of the control operation.

In FIG. 3, the same parts as in FIG. 1 are designated by the same reference numerals. In Figure 3, 31 is ? in Figure 1? 1 shows a portion including a blower/air blower 1, a conveyance path 3, and a demand-side capacity controller 4 (does not include load). 32 to 36 indicate control by the regulator 6 of FIG. That is, 32 is a manipulated variable transmitter that receives the manipulated variable feedback signal (bon f/blower capacity signal @ in FIG. 1) of the pon f/blower capacity controller 2 and outputs a manipulated variable feedback signal value PVI. 33 is feed -? 7, receives the signal value PVI, and sets f IJ.

This is a characteristic expression calculation unit that performs calculations using the characteristic expressions that have been set. 34 is a deviation output section which outputs the pressure difference between the output signal from the characteristic equation calculation section 33 and the control amount feed signal PV2 (pressure signal ■ in FIG. 1) from the pressure detector 5. Reference numeral 35 denotes a control calculation section which receives the deviation of the deviation output section 34 and performs control to reduce the deviation so that the deviation disappears. 36 is a control signal output processing section which receives the output signal MV of the control calculation section 35 and outputs a control signal MV' (circle in FIG. 1).

In FIG. 4, the manipulated variable feed signal value pvt is input at step S1. In step S2, the characteristic formula
Now that the return is set, it's time to move on.

In block S3, calculation R-f (PVI) based on the characteristic equation is executed. In step S4, the pressure needle side value PV2 is input. Control calculation/return is set in step and de S5, and R is the target value in step and fs6.

A control calculation is performed using PV2 as a control value. In step S7, signal processing for stabilizing the control system is performed, and a control signal is output to the blower/blower capacity controller 2 in step S8.

Referring to FIG. 5, the embodiment of FIG.
An example of application to a cold water/hot water system is shown.

In FIG. 5, 50 is a heat source system, 51 is a pump,
52 is an inverter that is a rotation speed controller for the pump 51. 5=1 is a 2-way ilt control valve which is a demand side capacity controller. 55 is a differential pressure transmitter that outputs the difference between the pressure in the supply hair goo 57 and the pressure in the return goo 58; 56 is a regulator.

57 is goo to supply, 58 is goo to return. 59 is an air conditioner, and 60 is a load side system. ■ is the differential pressure signal, @ is the rotation speed feeder.

The signal is the rotation speed control signal.

Referring to FIG. 6, there is shown an example in which the embodiment of FIG. 1 is applied to an air blowing static pressure control system in variable air volume air conditioner equipment. In FIG. 6, 61 is a blower, and 62 is an inverter that is a rotation speed controller for the blower 61. In FIG. 63 is a wind guide, 64 is a demand side capacity controller, VAV unit (
Variable air volume uni.

). 65 is a pressure transmitter, and 66 is a regulator.

67 is an air conditioner, and 68 is a room thermostat.

It is. ■ is a pressure signal, @ is a rotational speed feed signal, and O is a rotational speed control signal.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a regulator that receives a fluid conveyance capacity signal indicating the current fluid conveyance capacity from a fluid conveyance device such as a pump or a blower as a feed signal, it is possible to The existing flow rate or air volume measuring device becomes unnecessary. Therefore, installation work for a flow rate or air volume measuring device and instrumentation wiring work are unnecessary.

Especially when performing improvement work on existing equipment.

No repair work such as painting is required since II'L.

[Brief explanation of the drawing]

Figure 1 shows an embodiment of the present invention. Figure 2 is a diagram showing air volume/water volume-pressure characteristics to explain the operation of Figure 1. A professional diagram to explain the control in Figure 2, Figure 1 is a diagram of Figure 2:!ill zl
Figure 5 is a diagram showing a flowchart of the operation, applying the actual Mj example in Figure 1 to the cold water/hot water system of air conditioning equipment.
The illustrated diagram, Figure 6, is a diagram showing an example of applying the actual example of Figure 7J1 to an air blow static pressure control system in variable air volume air conditioner equipment. 1 Bon -7°/Blower, 2...Moon? Knob/Blower capacity control: →,, C Conveyance path, 1 Demand side capacity controller, 51 Moka detector, 6...Adjuster. Fig. 1 6 Adjuster Fig. 2 - Volume/Ice quantity □ 10 ---------Delivery pressure (difference ri) Target curved edge 3
Figure 4

Claims (1)

[Claims] 1. In a system that includes a fluid transfer device whose fluid transfer capacity can be changed and sends fluid to a load via a transfer path, the fluid pressure provided on the fluid delivery side of the fluid transfer device is adjusted. a detector for measuring; and a regulator that receives a pressure signal output from the detector and a fluid conveyance capacity signal indicating the current fluid conveyance capacity from the fluid conveyance device; A target value of the fluid pressure on the fluid delivery side of the fluid transport device for each fluid transport capacity is set in advance, and the regulator adjusts the pressure indicated by the pressure signal to a target value corresponding to the transport capacity indicated by the fluid capacity signal. An automatic pressure control method, characterized in that the fluid transport capacity of the fluid transport device is controlled to match a pressure value.