Test macro of engine pedestal and method for constant-velocity control

Abstract

The invention discloses an engine bench test system and a constant speed control method thereof. The system includes a torque sensor (2), a motor (3), a computer measurement and control system (4), and an AC frequency converter (5); The engine, the AC inverter, and the torque sensor are electrically connected; the AC inverter is electrically connected to the motor; one end of the torque sensor (2) is rigidly connected with the output shaft of the motor (3), and the other end is used for coaxial rigid connection with the output shaft of the engine. connect. By directly controlling the speed of the motor, the engine is stabilized at the set speed point, with high control precision, small fluctuations, and a smooth adjustment process. The maximum fluctuation of each speed point is about 1rpm. It solves the problem that the torque control method cannot stabilize the speed at the set speed under severe working conditions such as engine performance decline, single-cylinder fire failure, and short-term oil shortage, and truly meets the requirements of the engine test.

Description

【Technical field】 [0001] The invention relates to an engine bench testing system and a speed control method for testing the performance of an automobile engine on the bench. 【Background technique】 [0002] In the bench test of automobile engine, the constant speed control of the engine has always been the key technology for the experiment of engine external characteristics and load characteristics. No matter what kind of dynamometer is used, the conventional control method uses the load torque of the dynamometer as the direct control object, and dynamically adjusts the load torque through torque control to balance the change of the engine's power output, so that The engine can stabilize at a certain set speed point. Through practice, it is found that the control results of this method are not very ideal. When the engine performance declines, single-cylinder misfiring, short-term fuel shortage, etc., the rapid change of its power output usually makes the system extremely uns...

AI Technical Summary

Problems solved by technology

Through practice, it is found that the control results of this method are not very ideal. When the engine performance declines, single-cylinder misfiring, short-term fuel shortage, etc., the rapid change of its power output usually makes the system extremely unstable. The speed fluctuates greatly. In these cases, it is impossible to test the performance parameters of the engine such as torque and power in time, which makes the experiment meaningless to some extent.

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