SU1180534A1 - Apparatus for controlling the working duty of fan unit - Google Patents

Abstract

A FAN INSTALLATION MODE CONTROL DEVICE containing a series-connected first subtractive element, a first threshold element, a fan speed control unit and a first actuator, as well as a performance tandem unit and a performance sensor connected respectively to the first and second inputs of the first subtracting element, sensor temperature difference connected to the first input of the second outgoing element, a clock generator, an OR element and serially connecting The first element NO, connected to the output of the first threshold element, the blade position control unit and the second actuator, characterized in that. it is equipped with a pulse shaper, the first and second elements AND, the second element NOT, the second threshold element, analog and logical storage elements, while the output of the first element is NOT connected to the first input of the first element AND and through the pulse shaper to the first input the second element And, to the second INPUT of which is connected the second element NOT, the output of the second element And is connected to the installation i input of the logical storage element, the first output of the clock gene (L C ratora, the input of which is connected to the first element I, is connected to the first input of the analog storage element, to the second input of which the temperature differential sensor is connected, and the second output of the clock generator to the synchronizing input of the logical memory element, SP to the second input of which an analog storage element is connected, Au 41 through the second threshold element is connected to the information input of a logical storage element whose outputs are connected to corresponding; the corresponding inputs of the fan speed control unit, the blade position control unit, and the PIU element. the output of which is connected to the second input of the first element AND and to the input of the second element NOT.

Description

The invention relates to controlling the mode of operation of a fan installation and can be used to automatically regulate the main ventilation fan of a shaft.

The purpose of the invention is to increase the aerodynamic stability and efficiency of the fan installation with possible changes in the aerodynamic resistance of the ventilation network.

Fig. 1 is an electrical functional diagram of a device controlling the operating mode of the fan-15 unit in Fig. 2 is a graph of efficiency (h) versus angle of rotation of the blades of the guide vane @ prm of the various aerodynamic connections of the valves of the dione network in FIG. 3 - graphs of the aerodynamic family: fan characteristics in the coordinates of the capacity (Q) - head (N.) at different angles of rotation of the blades of the guide apparatus 0 ° and the graph of aerodynamic resistance with ventilation grids; Fig. 4 are time diagrams that explain the operation of the device. The control unit of the fan unit contains a fan unit 1, equipped with an adjustable electric drive and a control unit, on which the performance sensor 2 is installed, the output of which is connected to the first input - the first subtractive element 3, the second input of which is connected to the unit 4 of the production task , the output of the element is connected to the first threshold element 5 with the dead zone, 13 is full 1 on the basis of two comparator the output of the element 5 is connected to the unit at an accelerated speed a fan with a corresponding actuator 7 and through the first element EE 8 with a driver of 9 W-1 pulses (one-shot), with one of the inputs of the first element and the match circuit 10 and with a blocking input of the guide vanes 11; unit 11 is connected to the corresponding 111 1m actuator 12 The output of the temperature differential sensor 13 installed in the channel of the veins of TimHTopa is connected to the information

By the input of the analog storage element 14, the control input of which is connected to the first output of the clock generator 15, the output of the temperature differential sensor 13 is connected to the first input of the second subtractive element 16, and the output of the analog storage element 14 is connected to the second input of the 14 the threshold element 17 with the dead zone, made on the basis of two comparators, is connected to the information input of the logical storage element 18 of storing the sign of the increment, with nym input member 18 is connected to the output of the second AND gate. a matching circuit 19, one of the inputs of which is connected to the output of the imaging unit 9 and myco5 and the other through the second, the NOT element 20 is connected to another input of the first matching circuit 10 and through the circuit 21 OR to the outputs of the increment sign logic element 18, the outputs of which are also connected with the fan speed control unit 6 and with the control unit 11 position of the blades of the guide vane. The output of the first coincidence circuit 10 is connected to the input of the clock generator 15, the second output of which is connected to the synchronous input of the logical sign 18 element of the increment sign, the preset circuits (not shown) are also connected to the installation input of which. The device works as follows. The signal from the sensor 2 of the actual performance of the fan installation is fed to the first input of the first subtractive element 3, to the second input of which the signal from the capacity setting unit 4 is input, and a difference signal Q is generated at the output of element 3, which passes the first threshold element 5 if The condition is, (1) where & - the dead zone of the threshold element 5. From the output of the threshold element 5, the signal of the sign L Q is fed to the input of the fan speed control unit b, the output of which is the control signal AX A-SigniQ,. (2) where A is the transmission coefficient of block 6 by the first information kyap. At the same time, at the output of the first element of the HE - inverter 8 there is no signal, which prohibits controlling the position of the blades of the guide vanes, and in the preset chains the logic element 18 of the increment sign memorization is set to correspond to an increase in the angle of the blades of the guide vanes. The signal ix is supplied to the first actuator 7, which in turn affects the part of the fan shaft rotation until the moment when. (3) Enforcement of this condition resulted in the removal of the signal from the input of the fan speed control unit 6 (the first information channel) and one time from the input of the first inverter 8. At the output of the last, a signal appears that removes the prohibition of the operation of the control unit 11 for hitting the blades of the guiding apparatus, starts the one-shot 9 and enters one of the inputs of the first matching circuit 10, to another second input of which receives a signal from the logic element 18 increments through the mark storing circuit 21 concurrently with or prohibition SG through an inverter 20 to supply the signal from the monostable multivibrator 9 through BTopjno coincidence circuit 19, for storing zttravleni element 18 increments sign. The presence of two signals at the input of the first matching circuit 10 permits the operation of a two-phase clock generator 15 whose first phase pulse (Fig. 4b) permits storing the first current value of the temperature differential from the sensor 13 in the analog storage element 14 (Fig. 4d). proportional to the QDC value of the fan operation at the time point C. At the output of the second subtractive circuit 16, the difference signal between the current value (t) and value and (t at time t (Fig. 4a), i.e. Signa Sign (t) - (t (tf) J.) ) This signal passes the threshold element 17 if the condition (4 / t / /) is fulfilled, (5) where d is the dead zone of the threshold element 17. At the two outputs of the element 17, the signal of the increment sign of the CCT is generated, which is memorized in element 18 at the time tj, i.e. at the time of arrival of the pulse 15 from the generator in the second phase (Fig. 4b) at its clock input. The time current, - t, is determined from the condition of completion of the transient process in order to measure the temperature difference in the fan channel and is approximately 10-15 s. The signals at both outputs of the increment sign memorizing element 18 are commands for appropriate control in the direction of working both in the blade control unit 11 of the guide vane and in the fan speed control unit 6 with the control action (LH) (6) where A is the transmission coefficient of unit 6 on the second information channel, moreover. In the event of a violation of condition (5), the output signals become zero. In this case, the operation of the generator 15 is prohibited and the passage of a pulse from the one-shot 9 through the coincidence circuit 19 to the installation of the increment sign element 18, at which its output signals correspond to an increase in the angle of the guide vanes, is permitted. After that, through the scheme. . 21 and the first coincidence circuit 10 is allowed to operate the clock generator 15. Moreover, if condition (5) is met, then the cycle described above repeats, starting with a new pulse in the first phase of the generator 15. The use of the proposed device as compared to the known will allow to increase the aerodynamic stability and efficiency of the fan installation when changing the aerodynamic resistance of the network.

Fig 1

Max

0.9 max

+ 10 ° Phi2.2

-20 ° &

-10 °

Claims (1)

FAN OPERATION CONTROL DEVICE, comprising a first subtracting element, a first threshold element, a fan speed control unit and a first actuator in series, as well as a capacity demand unit and a sensor connected to the first and second axes, respectively the inputs of the first subtracting element, a temperature differential sensor connected to the first input of the second subtracting element, a clock, an OR element and connected in series e first element NOT connected to the output of the first threshold element, the blade position control unit and the second actuator, characterized in that, in order to increase aerodynamic stability and efficiency, it is equipped with a pulse shaper, the first and second elements AND, the second element NOT, the second a threshold element, analog and logical memory elements, while the output of the first element is NOT connected to the first input of the first element And and through the pulse former to the first input of the second element And, to the second to the second input of which the second element is NOT connected, the output of the second AND element is connected to the installation input of the logical memory element, the first output of the clock generator, the first element of which is connected to the input ? ry, and the second output of the clock generator is connected to the synchronizing input of the logical storage element, the output of the second subtracting element, the analogue storage element is connected to its second input, is connected through the second threshold element to the information input of the logical storage element, the outputs of which are connected to sootg sponding inputs ¹ · fan speed control unit, the position control unit and the blades of the OR '> whose output is connected to the second input of the first aND gate and to an input vtorog NOT element.