SU798697A2 - Electric engine speed controller - Google Patents

Description

one

The invention relates to automation, in particular to speed controllers for electric motors for air conditioning systems.

According to the main av.s.-. No. 430353 is well-known for controlling the speed of an electric motor, which contains an induction speed sensor connected to an amplifier, a control signal that is connected to the output of the amplifier, and the output to the phase-sensitive device 1

The disadvantage of the regulator is low accuracy and low speed.

The purpose of the invention is to improve the accuracy and speed of the controller.

This goal is achieved by the fact that the controller contains a storage capacitor, a synchronizer and two keys, the output of the control signal shaper is connected to the phase sensitive device input via the first switch, the smoothing RG circuit resistor is connected to the common bus through the second switch, which stores the capacitor VC. It is connected between the input of the phase-sensitive device and the common bus, and the outputs of the synchronizer are connected to the corresponding control inputs of the first and second keys.

FIG. 1 schematically shows a regulator; in fig. 2 - diagrams for example. zheniy.

The controller consists of an induction sensor 1 turn, an amplifier 2, a control signal generator 3, with an output voltage proportional to the frequency, the output of which is connected to a smoothing R.C circuit 4 consisting of a resistor 5 and a capacitor 6, keys 7 and 8 with embedded control circuits, a storage capacitor 9, a synchronizer 10 with paraphase outputs 11 and 12 connected to the control circuits of the corresponding electronic switches, a phase-sensitive device 13, whose outputs

0 connected to the windings of the drive. 14, gate TB 7 regulating the supply of air to the turbo-cooler 16 through the pipeline 17.

5 The regulator operates as follows.

. When air is supplied to the turbo-cooler 16 via line 17, a voltage is generated on sensor 1 (Fig. 2a).

0 which goes to the amplifier-limiter 2 and from its output {figure 2, b to the imaging unit 3 and the synchronizer 10

In the steady state, capacitors 6 and 9 are charged to a voltage proportional to the frequency of the input signal of the driver 3.

Until tg, the key 7 is open, and the key 8 is closed, the capacitor 9 saves the energy stored earlier. After the moment tg during the positive half-wave of the signal from the output of the amplifier-limiter 2 (figure 2, b), the synchronizer 10 generates paraphase signals at the outputs 11 and 12 (figure 2, c, d). In this case, for the time T (Fig. 2, c), the switch 7 is closed under the action of a pulse, and the switch 8 is opened under the action of a pulse (Fig. 2, d). The capacitor 6 is connected in parallel to the capacitor 9 and their voltages are compared. In the steady state, the voltage value is confirmed. the capacitor 9A in transient modes changes the voltage on the capacitor 9 and for each period of the input signal is established: arithmetic average of the voltages of capacitors b and 9 during less time than fg, since capacitors 6 and 9 take no more than 0, 01 microfarad After the end of the pulse, the key 7 is opened, and the key 8 is closed and before the negative half-wave begins, the capacitor b is discharged to the resistor 5. The output of the shaping device 3 is switched off during the whole positive half-period. The capacitor 9 until the next pulse from the synchronizer 10 retains the previous value of the voltage (figure 2, e), and the capacitor b during the negative half-period from the output of the booster amplifier is charged (figure 2, d). The voltage on the capacitor b during the period of the input signal has a large value of ripple, while. the voltage across the capacitor 9 is constant (in steady state). Depending on the increase or decrease in the frequency of the input signal, the voltage on the capacitor 9 and from one of the outputs of the phase-sensitive device 13 increases or decreases.

The voltage is applied to the appropriate winding of the electric drive, driving the valve 15, which changes the air supply through the pipeline 17 to the turbo-fridge 16. The rpm of the turbo-cooler, respectively, decreases or increases.

I.

Claims (1)

1. USSR author's certificate No. 430353, cl. G 05 B 11/26, 1972 0 (prototype. FIG. 2