SU1485378A1 - Controllable electromachine dc-to-ac converter for powering inductional gyromotor - Google Patents

Description

The invention relates to electrical engineering. The purpose of the invention increase efficiency. The converter is designed to power the motor and contains a DC motor 1

with the measuring body speed 4, kinematically associated with

it is a synchronous generator 2 with a voltage meter 5, a load current sensor 10, the output of which is connected to the input of the frequency meter 4 through the first nonlinear voltage converter (NP) 11, and through the second NP to the input of the frequency meter 4. Characteristics "input - output" of each NP contains zones: insensitivity, proportionality and restrictions. When the load current exceeds the dead zone of the first NP, the output voltage of the generator decreases and the power consumed by the load box does not exceed the allowed for the generator. When the load current exceeds the deadband of the second NP, the frequency of the output voltage decreases. Such a functional dependence of voltage and frequency on the magnitude of the load current allows the use of a lower power converter in the case of its use as a power source of the gyromotor and at the same time to reduce the acceleration time of the gnomotor, 2 Il.

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The invention relates to electrical engineering and can be used to create an adjustable electric machine of a DC / AC converter designed to supply power to a predominantly gyromotor based on an induction motor.

The purpose of the invention is to increase efficiency.

FIG. 1 shows the block diagram of the proposed converter; in fig. 2 (a and b) - characteristics "input-output” of nonlinear converters.

The direct-current driver 1 is kine- -, 5 mathematically connected to the synchronous generator 2, to the phases of which the load (gyromotor) is connected. 3. The inputs of the measuring unit of frequency 4 and voltage 5 are connected to the generator phase. 20 The output of the measuring unit 4 frequencies connected to the input of the amplifier-adder 6, and the output of the measuring body 5 voltage is connected to the input of the amplifier-adder 7, the outputs of the amplifiers 25 and adders 6 and 7 are connected to the windings 8 and 9 of the excitation of the engine and generator, respectively. These elements form a closed system of frequency control and 30 nag voltage on the deviation. A sensor is installed in the load circuit of the generator.

10 current, the output of which is connected to the inputs of nonlinear converters

11 and 12. The output of the nonlinear converter ^ 5 of the detector 11 is connected to the second input of the amplifier-adder 7, and the output of the second nonlinear converter

12 is connected to the second input of the amplifier-adder 6. Here 1 "is the installed value of the gyromotor current;

1 ^ is the maximum allowable value of the generator current at the rated output voltage, Ι, ₂ ;

1 _? - starting current of the gyromotor; - 45

riromotor current at which the generator frequency starts to rise. The value 1 ^ is chosen for a specific converter and gyromotor from the condition of the minimum acceleration time,

The Converter operates as follows.

At the time of starting the gyromotor, the current consumed by it is greater than 1 _? therefore, the signal from the nonlinear converter $ 11 is maximum, which leads to a decrease in the supply voltage of the gyromotor and limiting the current consumed at the level In general, Ι _ή <1 ^, therefore the signal from the nonlinear converter 12 is also maximum and ensures a reduction in the engine speed to level determined by the permissible motor armature current. The value by which the frequency decreases is ensured by choosing the level of limitation in the characteristic of the nonlinear converter 12. As the gyromotor accelerates, the current consumed by it starts to decrease, which leads to a decrease in the signal * from the nonlinear converter 11 and an increase in the output voltage of the converter. This allows you to accelerate the gyromotor in the range of current consumed by it from 1 ^ to s

almost constant power consumption from the converter. When reducing the current consumption to Ι4, the engine rotation frequency starts to increase, and hence the frequency of the output voltage, as the signal at the output of the nonlinear converter 12 decreases. At a current of 1 _{2 the} output voltage of the converter reaches the nominal value, and at a current of 1 ₄ and the frequency of the output voltage becomes nominal. When the current consumption does not exceed the values of I,, the amplitude and frequency of the output voltage of the converter are maintained at nominal levels, which is provided by dead zones in the characteristics of nonlinear converters 11 and 12.

Thus, an electromotor converter of lower power can be used to power the gyromotor, since power consumption is limited by controlling the amplitude of the output voltage of the converter, and the acceleration time of the gyromotor is not only not increased, but also somewhat reduced due to the fact that the gyromotor is powered by a lower part of the acceleration frequency and, therefore, its torque is increased compared with the moment during acceleration at the nominal frequency “

Claims (1)

Claim Adjustable! a DC-to-AC electric converter for powering an asynchronous gyromotor containing a DC motor kinematic connected with there is a synchronous generator, a generator load current sensor, frequency and voltage measuring organs, inputs connected to the phase of the generator output voltage, and two amplifiers-adders, the output of the frequency measuring element being connected to the first input of the first totalizer amplifier, the output of which is connected to the motor excitation winding, the output of the measuring body voltage is connected to the first input of the second amplifier-adder, the output of which 1485378 6 connected to the excitation winding of the generator, characterized in that, in order to increase efficiency, two non-linear voltage converters with dead zones, proportionality and limitation are introduced into it, the inputs of which are connected to the output of the load current sensor Yu generator, the output of the first nonlinear converter is connected to the second input of the second amplifier-adder, and the output of the second - to the second input of the first amplifier-adder. Phil.2.