Patent Application
20190178149
The present disclosure generally relates to a supercharger system and a method for operating an internal combustion engine. More particularly, the present disclosure relates to a supercharger system and a method for improved engine transient response.
Generally, a turbocharger is employed on an engine for increasing a pressure of intake air (boost) entering combustion chambers of the engine. The turbocharger may be typically driven by a stream of exhaust gases exiting the combustion chambers of the engine. When the engine is operating on a low load, the turbocharger may not be able to provide a desired pressure to the intake air to meet any sudden load applied on the engine.
In some applications, the engine may be used to drive an electrical generator. When a sudden electrical load is applied on the generator, the engine may be required to quickly ramp up a speed of the engine, so that the generator output meets a minimum frequency and′ voltage requirements associated with the electrical load. However, the turbocharger associated with the engine may not be able to provide enough pressure to the intake air for combustion of a required amount of fuel to quickly increase the speed of the engine.
U.S. Pat. No. 9,228,487 (hereinafter referred to as “the '487 patent”) describes an engine having a turbocharger and a supercharger. The '487 patent discloses that compressed air from the supercharger is being fed to a suction side (i.e. air inlet side) of a compressor associated with the turbocharger in order to meet a sudden increase in load demand on the engine. However, in this kind of arrangement, for the supercharger to provide a boost pressure equivalent to that of the turbocharger running at high speeds may require higher capacity superchargers, requiring larger space and higher cost.
In one aspect of the present disclosure, a supercharger system for an engine having a turbocharger is provided. The supercharger system includes a supercharger driver and an air inlet. The supercharger system also includes a supercharger compressor mechanically coupled to the supercharger driver. The supercharger compressor includes a supercharger compressor inlet and a supercharger compressor outlet. The supercharger compressor inlet is in fluid communication with the air inlet. The supercharger compressor outlet is in fluid communication with a turbocharger turbine inlet.
In another aspect of the present disclosure, an engine is provided. The engine includes a plurality of combustion chambers. Each of the plurality of combustion chambers is in fluid communication with an air intake manifold and an exhaust manifold of the engine. The engine also includes a turbocharger having a turbocharger turbine. The turbocharger turbine includes a turbocharger turbine inlet in fluid communication with the exhaust manifold of the engine. The engine further includes a supercharger system. The supercharger system includes a supercharger driver and an air inlet. The supercharger system also includes a supercharger compressor mechanically coupled to the supercharger driver. The supercharger compressor includes a supercharger compressor inlet and a supercharger compressor outlet. The supercharger compressor inlet is in fluid communication with the air inlet. The supercharger compressor outlet is in fluid communication with the turbocharger turbine inlet.
A method is provided for operating an engine having a turbocharger and a supercharger and the engine is coupled to a generator. The method includes determining, by means of a controller, whether an intake air pressure or intake air flow rate of an air intake manifold is below a threshold, when the engine is running at low load. The method includes driving a supercharger compressor. The method includes receiving a flow of ambient air into the supercharger compressor. The method further includes pressurizing the received ambient air by the supercharger compressor. The method further includes providing pressurized air from the supercharger compressor to an exhaust manifold of the engine to provide a flow of pressurized air to turbocharger turbine inlet. The method further includes sensing, by means of a controller, a sudden additional load on the engine. The method includes increasing an amount of fuel into a plurality of the combustion chambers of the engine.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
The features and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to same or like parts.
As shown in
The engine 102 further includes a turbocharger 114 that is fluidly coupled to the engine 102. The turbocharger 114 includes a turbocharger turbine 116 and a turbocharger compressor 118 mechanically coupled to the turbocharger turbine 116 through a connecting shaft 120. The turbocharger turbine 116 includes a turbocharger turbine inlet 122 and a turbocharger turbine outlet 124. The turbocharger turbine inlet 122 is in fluid communication with the exhaust manifold 110 of the engine 102 via an exhaust inlet line 121. The turbocharger turbine outlet 124 may be fluidly coupled with an exhaust outlet line 126, which may direct exhaust gases to an aftertreatment module, muffler exhaust stack, or other components (not shown). Further, in an embodiment, the engine 102 may include multiple turbochargers such as turbochargers 114. Also, the exhaust manifold 110 may be divided into multiple sections (not shown), fluidly coupled with the turbocharger turbine inlet 122.
The turbocharger compressor 118 includes a turbocharger compressor inlet 128 and a turbocharger compressor outlet 130. The turbocharger compressor inlet 128 is fluidly coupled to an air intake line 132 (hereinafter referred to as “the first air intake line”). The first air intake line 132 is configured to receive a flow of ambient air from an air inlet 133 in fluid communication with an ambient air source. As shown in the illustrated embodiment of
Further as shown in the illustrated embodiment of
The engine 102 may also include a supercharger system 138. The supercharger system 138 includes a supercharger driver 140, and a supercharger compressor 144 mechanically coupled to the supercharger driver 140. In the illustrated embodiment of
The supercharger compressor 144 includes a supercharger compressor inlet 146 and a supercharger compressor outlet 148. The supercharger compressor inlet 146 is in fluid communication with an air inlet 142 of the supercharger system 138. As shown in the illustrated embodiment of
The supercharger compressor outlet 148 may be in fluid communication with the exhaust manifold 110 of the engine 102. As shown in the illustrated embodiment of
In the embodiment shown in
The engine 102 may be configured to operatively drive a load, for example, an electrical generator 158 as shown in
As shown in the
During the operation of the supercharger system 138, the controller 164 may start the supercharger driver 140 to operate the supercharger compressor 144. The supercharger compressor 144 receives a flow of ambient air from the air inlet 142 and pressurizes the received ambient air. Further, the shut off valve 156 is opened to provide a flow of the pressurized air from the compressor outlet 148 to the exhaust manifold 100 of the engine 102, so that the flow of the pressurized air could be provided to the turbine inlet 122 associated with the turbocharger 114. The addition of the compressed air from the supercharger compressor 144 into the exhaust manifold 110 and subsequently to the turbocharger turbine inlet 122 may impart an additional kinetic energy to the turbocharger turbine 116 thereby driving the turbocharger 114 at a speed greater than would be possible without the supercharger 138. Accordingly, the turbocharger turbine 116 may be able to drive the turbocharger compressor 118 at a greater speed to provide a greater intake air pressure in the air intake manifold 106.
As the supercharger system 138 is in continuous operation when the engine 102 is running at low load, there is sufficient air intake pressure in the air intake manifold 106 so that the controller 164 may increase an amount of fuel to be supplied to each of the combustion chambers 104 in an event of the sudden increase in the load on the engine 102. This may enable the engine 102 to have a faster response during the transient condition (i.e. when the engine 102 is transitioning from the low load to meet the sudden application of load on the engine 102). This sudden additional load may be applied on the engine 102 because of a sudden increase in electrical load on the generator 158. In an embodiment, the controller 164 increases the amount of fuel to be supplied to increase the speed of the engine 102 so that the generator 158 may respond to produce frequency and voltage associated with the required electrical load.
Further, the controller 164 may initiate a transition of operating conditions of the engine 102 to accommodate the sudden increase in the electrical load on the generator 158. The controller 164 may determine whether the pressure of the air in the air intake manifold 106 is sufficient to burn enough amount of fuel to meet the sudden additional load applied on the engine 102. The controller 164 may further determine whether the operating conditions of the engine 102 is transitioned to accommodate the sudden increase in the electrical load on the generator 158. Accordingly, the controller 164 may close the shut-off valve 156 and disable the operation of the supercharger system 138.
The controller 164 may also include various software and/or hardware components that are configured to perform functions consistent with the present disclosure. Moreover, the controller 164 may be a standalone control system or may be configured to cooperate with an existing electronic control module (ECM) (not shown) of a machine, for instance, an engine may be located onboard a vehicle, or an engine generator. Furthermore, it may be noted that the controller 164 may embody a single microprocessor or multiple microprocessors that include components for selectively and independently controlling operation of the supercharger compressor 144 and the shut off valve 156 associated with the supercharger system 138.
The supercharger system 138 may be operated when the engine 102 is operating at a low load, at which the turbocharger 114 alone may not be able to provide the desired intake air pressure for combusting an amount of fuel to meet the sudden additional load, if applied, on the engine 102. The sudden additional load on the engine 102 may be because of a sudden additional electric load on the generator 158 driven by the engine 102.
At step 212, the method 200 includes sensing a sudden additional load on the engine 102. Accordingly, at step 214, the method 200 includes increasing an amount of fuel to be supplied to each of the combustion chambers 104, as there is sufficient amount of pressurized air supplied to each of the combustion chambers 104 to combust the increased amount of fuel. In an embodiment, the increase in the amount of fuel supplied is to increase the speed of the engine 102 so that the generator 158 may respond to produce frequency and voltage associated with the required electrical load. Further, upon determining that the engine 102 is transitioned to accommodate the additional load, the shut off valve is closed 156 and the supercharger system 138 operation is disabled.
Embodiments of the present disclosure have applicability in preventing the engine 102 from lugging or stalling when a surge in the load demand occurs on the engine 102, for instance, when the surge occurs in the amount of the electrical load on the generator 158 that is coupled to the engine 102. Additionally, embodiments of the present disclosure also have applicability for use in continuously developing boost pressure for the intake air at the turbocharger 114 when associated engine 102 is suddenly required to transition from a low load operating condition to a high load operating condition to meet the surge in the load demand. Also, the supercharger system 138 of the present disclosure, provides a simple and compact arrangement resulting in lower space requirement around the engine 102 as compared to usage of storage tanks with the compressed air.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof
