RU1795388C - Engine testing device - Google Patents

Abstract

The invention relates to electrical engineering and can be used to test vehicle engines. The purpose of the invention: to provide a change in the modeling moment of inertia to create dynamic loads on the engine under test. The device comprises a load unit 1, a converter 2, a torque sensor 3, a scaling amplifier 4, an integrator 5. a setter 6, a multiplier 7. The test engine 8 is connected to the output shaft of the load unit 1. By changing the transmission coefficient of the signal from the moment sensor 3 using a setter 8 scaling amplifier 4 and the rate of change of the signal with the help of integrator 5, dynamic loads are simulated with reduced moment of inertia taking into account external factors affecting the motor under test, 2 il. (/ WITH

Description

The invention relates to electrical engineering and can be used to test vehicle engines.

A load device for testing automated electric drives is known, comprising a load machine with a converter, a speed sensor and a dynamic current sensor of the tested machine, the output of which is connected to the first input of the converter of the load machine, the second input of which is connected to a speed sensor, and the third input is connected to the torque generator.

Closest to the present is a load testing device for engines, comprising a load unit with a converter, torque, speed and path sensors, time and static torque sensors, the outputs of which are connected to the inputs of the load unit converter.

A disadvantage of the known devices is the impossibility of creating with their help dynamic loads on the engine under test, since when the vehicle is moving, the engine experiences dynamic loads, which are functions of external influences, such as road conditions and reduced mass (moment of inertia), which can vary widely.

The purpose of the invention is to provide a change in the modeling moment of inertia to create dynamic loads on the engine under test.

The goal is achieved in that in a device for testing engines containing a load unit, a converter, the output of which is connected to the input

h y

(L w

with

00

load unit and torque sensor, a scaling amplifier, integrator, master and multiplier are introduced, the first input of the multiplier connected to the output of the torque sensor, the output of the master connected to the second input of the multiplier, the output of which is connected to the inputs of the integrator and the scaling amplifier, the outputs of which are connected to the first and second inputs of the converter, respectively.

In FIG. 1 shows a structural diagram of a load device; in FIG. 2 is a structural diagram of a device.

The load testing device for engines contains a load block 1, a converter 2, the output of which is connected to the input of the load block 1, a torque sensor 3, a scaling amplifier 4, an integrator 5, a setter 6 and a multiplier 7. The outputs of the integrator 5 are connected to the first and second inputs of the converter 2 and a scaling amplifier 4, respectively, their inputs are connected to the output of the multiplier 7, the first input of which is connected to the output of the moment sensor 3, and the second to the output of the master b, With the output shaft of the load Flock 1, the shaft is connected test engine 8.

As the load unit 1, one or two machine units can be used, the converter 2 can be made as an auxiliary converter, the setter 6 can be made in the form of an adjustable voltage divider or in the form of a program unit.

The principle of operation of the load device is explained using the block diagram shown in Fig. 2 (a DC motor is taken as the test machine), where the following designations are adopted: I - total moment of inertia of the load unit 1 and test motor 8; Ci KTi; Ca CT2; Ti and Ta - magnetic fluxes, respectively, of the load unit 1 and the test engine 8; RI and Ra are the core resistance of load block 1 and motor 8 under test (core inductance is not taken into account); Kp - transfer coefficient of the Converter 2; Ki - integrator transfer coefficient 5; y is the gain of the scaling amplifier 4, which is set equal to Ri s. v A - coefficient taking into account

the road position, varying from 0 to 1, and is set using the adjuster 6 of external factors.

The device operates as follows.

First, we assume that the moments Mi and Ma of the load and test machines are absent and the road condition is good, i.e. A 1. The voltage applied / 2 to the subject

engine 8, increase the moment (we are trying to disperse a vehicle that has a certain mass). Simultaneously with the increase in Ma, the moment Mi of the load motor will increase exactly by

the same value, but with the opposite sign. The dynamic moment which the engine must accelerate is zero, therefore, the o-speed of the tested engine 8 is zero. At the same time with

an increase in the moment Mg and the moment Mi appears at the input of the integrator 5. At the output of the integrator 5, a voltage grows in time, which reduces the voltage at the input of the converter 2 supplied from the output of the scaling amplifier 4 and thereby reduces the load moment block ML The rate of decrease in the moment Mi, and therefore the increase in speed w, depends

from the transfer coefficient of the integrator 5 Ki. In this way, acceleration of a vehicle with a certain mass is simulated. Changing Km, it is possible to simulate the change in mass (reduced to the shaft of the tested engine 8 moment of inertia) over a wide range.

Now suppose that the road condition is poor (ice), i.e. A 0. In this case, the real vehicle

stalls and engine 8 does not experience moment of resistance and mass. In the proposed device, when the moment Ma increases, the moment Mi will be equal to zero and the test machine will rotate by

idle, with moment of inertia I. If 0 A 1, then slippage of the wheels of the vehicle will be simulated. In this case, the test engine 8 will be affected by a certain moment of resistance and a moment of inertia.

Not shown is a resistance torque adjuster that connects to the second. the input of the integrator 5 (Fig, 1). The principle of operation of the device in this case remains the same,

only Mi will still contain a component of the resistance moment.

Thus, the proposed device for testing engines makes it possible to simulate dynamic loads with a given moment of inertia that can be varied widely and taking into account external factors (road conditions).

Claims (1)

SUMMARY OF THE INVENTION An engine testing device comprising a load unit, a converter, the output of which is connected to the input of the load unit, and a torque sensor, characterized in that a scaling amplifier, an integrator, a master, and a multiplier are introduced into the device to provide a change in the inertia moment of simulation. the first input of the multiplier is connected to the output of the torque sensor, the output of the master is connected to the second input of the multiplier, the output of which is connected to the inputs of the integrator and the scaling amplifier, the output whose odes are connected to the first and second inputs of the converter, respectively. Fig. { Ms / b // we. dfit / g. 8 Vt Load faoxf