Detection device and method for detecting pre-ignition of spark plug ignition type engine

Abstract

The invention belongs to the technical field of internal combustion engines and relates to an ionic current pre-ignition detection device and a control device and method for effectively inhabiting pre-ignition. The detection device for detecting pre-ignition of a spark plug ignition type engine comprises an ionic current detection system integrated to a spark plug ignition coil and transmits a detected pre-ignition signal to a pre-ignition recorder and a pre-ignition inhabiting actuator. The ionic current detection system detects whether a high pre-ignition ionic current signal exists or not from an ignition energy storage signal to an ignition moment, if the pre-ignition ionic current signal exists and is larger than a threshold value, it is determined that pre-ignition occurs in the current circulation; if the pre-ignition ionic current signal does not exist, it is determined that normal burning occurs. Compared with the prior art, the detection device applies an ionic current technology and can accurately detect a pre-ignition phenomenon before spark plug ignition, and oil is sprayed into a cylinder and an exhaust valve is turned on to achieve pre-ignition inhabiting, avoid acute knocking of an engine and protect the engine by cutting off an ignition signal.

Description

technical field [0001] The invention belongs to the technical field of internal combustion engines, and relates to an ion current detection pre-ignition device and a control device and method for effectively suppressing pre-ignition. Background technique [0002] In recent years, the development of high-pressure small-displacement gasoline engines has focused on knock control. By optimizing the cooling cycle, ignition timing, fuel injection strategy, continuous valve variable technology, compact combustion chamber design and higher intake pressure, etc. , so that the engine brake mean effective pressure (BMEP) is expected to reach 2.5MPa. However, as the engine load continues to increase, a sporadic and uncontrollable pre-ignition phenomenon appears at low speed and high load. Pre-ignition is sporadic and discontinuous, which makes it difficult for engine manufacturers to detect and control it effectively. In addition, pre-ignition tends to produce extremely high combustion...

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Problems solved by technology

[0005] In the existing research, Toyota Motor Co., Ltd. published the CN1683911A "Knock Judgment Device and Knock Judgment Method for Internal Combustion Engine" of the State Intellectual Property Office of the People's Republic of China by comparing the correlation coefficient for knock judgment with the preset knock judgment threshold. , and according to the comparison result, the knock determination threshold used in the knock determination of each combustion is corrected to improve the accuracy and reliability of knock determination, but it cannot be applied to the pre-ignition detection of supercharged engines

Mazda Motor Co., Ltd. applied air-fuel ratio enrichment to suppress pre-ignition in the CNIO2207037 patent of the State Intellectual Property Office of the People's Republic of China "Control Method and Control Device for Spark Ignition Engines", but the accuracy is poor because it does not use ion current detection , Shanghai Automotive Group, in the patent No. 103850852A "system and method for detecting engine pre-ignition", by detecting the ion current signal in the engine cylinder, calculating and calibrating the pre-ignition ion current judgment threshold, and calculating the ion current integral signal, and based on The ion current integral signal judges whether pre-ignition occurs in the current combustion cycle, so that the next combustion can be adjusted and optimized based on the judgment result

However, because this method uses the method of calculating the integral value of the ion current, the judgment speed is relatively slow, and the judgment can only be realized after the pre-ignition occurs in this cycle, and it cannot be realized before the ignition and at the early stage of the pre-ignition to realize whether the engine has pre-ignition. burn

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