SU760393A1 - Device for control of power-diode motor inverter - Google Patents

Description

The invention relates to the field of converting technology, namely to control systems of dependent 'inverters. ,

A device for controlling an inverter of a valve motor is known, consisting of position sensors, a block for isolating a switching EMF, an inverter control system, and an inverter control pulse generating system £ ΐ].

However, this device has overestimated overall performance.

The closest in technical essence is a device for controlling an inverter of a valve motor containing rotor position sensors and a pulse forming unit [2].

However, this device operates 20 with a constant ignition angle of the inverter thyristors, which is measured from the position of the rotor. As a result, the valve motor works with poor energy performance (low power factor, increased torque ripple),

The aim of the invention is to improve the regulatory properties of the device for controlling the inverter. thirty

The goal is achieved by the fact that the device for controlling the inverter of the valve motor, containing position sensors, rotors and control pulse generating units, is equipped with a phase _> detector, a pulse-width demodulator with variable conversion slope, a multiplier unit, a frequency divider, a distributor and a controlled generator, consisting of a zero-organ, a key reset element connected to an integrator, the input of which is connected to a voltage source proportional to the frequency of rotation of the valve motor Pure, as well as with the input for changing the steepness of the pulse-width demodulator and the first input of the multiplier unit, the second input of which is connected to the source of control voltage, the output of the multiplier unit is connected to one of the ^ inputs of the zero-organ, the other inputs of which are connected to the bias voltage source, with the outputs of the integrator and the pulse-width demodulator, and the output of the zero-organ is connected to the input of the frequency divider, the output of which is connected to the distributor, the output connected to the block forming the control impu sov and to the first input of the phase detector, a second input coupled to a position sensor and an output - to the input of the pulse-width demodulator.

In FIG. 1 and 2 are structural diagrams of the device.

The load of inverter 1 is οσ

2, on the shaft of which rotor position sensors 3 are installed, the outputs of which are connected to the first input of the phase detector 4, the output connected to the input of the pulse-width demodulator 5. The output of the controlled oscillator b, consisting of an integrator 7 with a key element 8 of reset 15 sec and null body 9 via a distributor 10 connected to the generator 11 of control pulses and the second input of the phase detector 4. Multiplier unit 12, one input of which sub 20 'is the key to the control voltage source, and _y p, the output is connected to one of the inputs ^ n l-body 9. The other inputs zero body 9 are connected to a bias voltage source 25 mi vyhoda- integrator 7 and the pulse-width demodulator 5.

In the diagram depicted in figure 2, between the output of the controlled oscillator b and the input of the pulse distributor 10, an uncontrolled frequency divider 13 is connected, and the second input of the phase detector 4 is connected to the output of the distributor 10.

'The operation of the device is as follows.

At a constant speed of rotation of the valve motor 2, the voltage and ₄ supplied to the input of the integrator 7 is constant. The voltage at the output of the pulse-width demodulator 5 is proportional to the phase shift between the pulses coming from the rotor position sensors 3 and the pulses coming from the output of the controlled generator b. The operation of the zero-organ 9 occurs' when the voltage * at the output of the integrator 7 is equal to the sum of the voltages: the bias voltage of the control voltage Nup1 from the output of the multiplier 12 and the voltage from the output of the pulse-width .....

demodulator 5. In this case, each magnitude of control voltage 11upr corresponds to its phase shift between the pulses of the sensors 3 position and ·: controlled generator 6. 55

When the control voltage u ^ changes, the voltage changes, at which the zero-organ 9 is triggered, and a phase shift occurs between the pulses of the sensors 3 posi ting '' '‘;

”'Given that the steepness of the pulse-width demodulator 5 changes in proportion to the rotational speed of engine 2, and the control voltage is informed by unit 12 as the product of the control voltage υ _{ν (} , _ρ . And voltage and $, the phase shift between the pulses from the 3 position sensors AND control pulses of the thyristor inverter 1 turns out to be linearly dependent on the control voltage “period of the range of change of frequency of rotation of the valve motor

2.

In the circuit shown in FIG. 1, a number of position sensors 3 is provided equal to the number of inverter arms.

So, for a three-phase bridge circuit, the number of position sensors will be six. In the block diagram of FIG. 2, the design of the sensor assembly 3 position simplified and contains one sensor. The latter is provided by connecting the second input of the phase detector 4 with one of the outputs of the pulse distributor 10.

In addition, due to the presence in the device of an uncontrolled frequency divider 13, the task of implementing a controlled generator b is greatly simplified.

Let, for example, the frequency of the pulses from the position sensor 3 be 20 Hz. Since the frequency of pulses arriving at the second input of the phase detector 4 from one of the buses of the distributor 10 should also be equal to 20 Hz, the frequency of pulses arriving at the distributor (with a 3-phase bridge circuit of the inverter) should be six times higher, t .e.

120 Hz. If the division coefficient of the divider 13 is 10, then the frequency of the controlled generator 6. will be equal to 1200 Hz, which greatly simplifies the task of its implementation.

Thus, the proposed device can improve the adjusting properties and energy characteristics of the valve motor

Claims (1)

Claim A device for controlling an inverter of a valve motor, comprising rotor position sensors and a control pulse generating unit, characterized in that, s ^; In order to improve the adjusting properties, it is equipped with a phase detector, a pulse-width demodulator with variable conversion slope, a multiplier unit, a frequency divider, a control pulse distributor and a control> VLM generator consisting of a zero-organ and a key reset element connected to an integrator, whose input connected to a voltage source proportional to the frequency of rotation of the valve motor, as well as to the input of the change in the slope of the pulse-width demodulator and the first input of the multiplier unit, the second input of which is connected to the source of control voltage, the output of the multiplier unit 5 is connected to one of the inputs of the zero-organ, the other inputs of which are connected to the source of bias voltage, with the outputs of the integrator and pulse-width demodulator, and the output of zero body is connected to the input of the frequency divider, the output of which is connected to the distributor, the output connected to the control pulse generation unit, and to the first input of the phase detector, the second input of which is connected to position sensors, and in move to the input of the pulse-width demodulator.