Compressor surge protector for electric assisted turbocharger
View Patent ↗Systems for preventing/controlling compressor surge in an electrically assisted turbocharger comprise a turbocharger having an electric motor disposed around a turbocharger shaft. The electric motor controller is electrically coupled to the electric motor for controlling the rotational movement provided by the electric motor to the turbocharger shaft. A memory is electrically coupled to the electric motor controller and comprises a multi-dimensional map of compressor surge conditions stored therein. Sensors are used to provide desired engine and/or turbocharger operating information for comparing against the stored map data. The sensors are electrically coupled to the electric motor controller. The controller plots the actual operating information provided by the sensors on the stored map to evaluate whether the turbocharger is operating in different operating regions. If the plotted turbocharger operation falls within a surge risk or surge state operating region, the motor controller operates the electric motor in a manner that reduces the rotational speed of the turbocharger shaft.
1. A method for controlling compressor surge in an electrically assisted turbocharger that is coupled to an internal combustion engine, the turbocharger including an electric motor disposed around a turbocharger shaft to provide rotational movement thereto, the method comprising the steps of:
sensing a first parameter indicative of the rotational speed of the internal combustion engine;
sensing a second parameter indicative of the rotational speed of the turbocharger shaft; and
controlling the electric motor responsive to said first and second parameters so as to avoid surge based on a multi-dimensional map correlating compressor surge conditions to the speed of the internal combustion engine and to the speed of the turbocharger, wherein the step of controlling is performed by an electric motor controller that is coupled to the electric motor and that includes a memory connected thereto having the multi-dimensional map of surge conditions stored therein, and wherein the step of controlling comprises the electric motor controller reversing power to the electric motor in response detected surge conditions.
2. A system for controlling compressor surge in an electrically assisted turbocharger that is coupled to an internal combustion engine comprising:
an electric motor disposed around a turbocharger shaft having attached thereto a compressor at one shaft end and a turbine at an opposite shaft end;
an electric motor controller electrically coupled to the electric motor;
a memory means electrically coupled to the electric motor controller, the memory means having a multi-dimensional map of compressor surge conditions stored therein; and
at least two sensors electrically coupled to the electric motor controller, the sensors being configured to monitor operating conditions of at least one of the turbocharger and an internal combustion engine coupled thereto;
the electric motor controller further configured to control operation of the electric motor responsive to signals provided from the sensors as correlated to the multi-dimensional map of surge conditions stored in the memory, wherein the electric motor controller is further configured to reverse power to the electric motor in response to signals from at least one of the engine speed sensor and turbocharger speed sensing means as correlated to the multi-dimensional map of surge conditions stored in the memory when a compressor surge condition is detected.
3. A system for controlling compressor surge in an electrically assisted turbocharger that is coupled to an internal combustion engine comprising:
an electric motor disposed around a turbocharger shaft to provide rotational movement thereto;
an electric motor controller electrically coupled to the electric motor for controlling the operation of the electric motor;
an engine speed sensor electrically coupled to the electric motor controller for sensing the rotational speed of the internal combustion engine;
a turbocharger speed sensing means coupled to the electric motor controller for sensing the rotational speed of the turbocharger shaft; and
a memory electrically coupled to the electric motor controller, the memory having a multi-dimensional map stored therein of surge conditions correlating to the speed of the internal combustion engine and to the speed of the turbocharger;
the electric motor controller further configured to control the electric motor responsive to the signals provided from the engine speed sensor and from the turbocharger speed sensing means as correlated to the multi-dimensional map of surge conditions stored in the memory, wherein the electric motor controller is further configured to reverse power to the electric motor in response to signals from at least one of the engine speed sensor and turbocharger speed sensing means as correlated to the multi-dimensional map of surge conditions stored in the memory when a compressor surge condition is detected.
4. A system for controlling compressor surge in an electrically assisted turbocharger that is coupled to an internal combustion engine comprising:
an electric motor disposed around a turbocharger shaft to provide rotational movement thereto;
an electric motor controller coupled to the electric motor for controlling rotational movement provided by the electric motor;
an intake air sensor coupled to the electric motor controller for sensing a volume of air entering the turbocharger;
a pressure ratio sensor coupled to the electric motor controller for sensing compressor pressure ratio; and
a memory electrically connected to the electric motor controller, the memory having a multi-dimensional map stored therein of surge conditions correlating to the volume of air entering the turbocharger and the compressor pressure ratio;
the electric motor controller further configured to control the electric motor responsive to the signals from the intake air sensor and from the pressure ratio sensor as correlated to the multi-dimensional map of surge conditions stored in the memory, wherein the electric motor controller is further configured to reverse power to the electric motor in response to signals from at least one of the air intake sensor and pressure ratio sensor as correlated to the multi-dimensional man of surge conditions stored the in the memory when a compressor surge condition is detected.