An exhaust valve includes a toroidal surface about an axis of rotation of the valve. The toroidal surface is positionable over a central exhaust port of an engine when lowered. The valve is raised by an actuator in response to increasing rotational speed of the crankshaft of the engine, thereby enlarging and raising the effective opening of the exhaust port. Lateral valve surfaces on either side of the toroidal surface close lateral exhaust ports when the valve is lowered. The lateral valve surfaces may be cylindrical and formed on fins.

A method for operating the two stroke engine provides that the fuel valve is controlled after the starting process in at least a quasi-steady state such that, on the basis of uninterruptedly successive blocks of successive revolutions of the crankshaft, the fuel valve is opened and closed exactly once within each block. Each block includes from two to twenty revolutions of the crankshaft. The fuel valve is opened over a crankshaft angle (α) of more than 360° within one block in at least one operating state. A control device is provided for controlling the fuel valve. A quasi-steady state of the two stroke engine is a state in which the throttle element is adjusted by less than 10% of the maximum adjustment of the throttle element over a crankshaft angle (α) of 360°.

A two-stroke engine (4) has a throttle motor (22) for driving a throttle valve (20), a fuel injection device (430) disposed in an intake system (18) including a crank chamber (420), and a control unit (24) controlling the throttle motor (22) and the fuel injection device. The two-stroke engine (4) is designed to achieve an engine rotation speed of 4,500 rpm to 7,000 rpm when the throttle valve (20) is fully open. The two-stroke engine (4) is operated with the throttle full open by the control unit (24), and a battery (8) is charged with electric power generated by a generator (6) using the two-stroke engine.

A method of operating a two-stroke cycle, opposed-piston engine comprising a pumping device coupled to pump air to cylinders of the engine through a charge air cooler and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders by which a thermal state of the exhaust sufficient to sustain thermal activation of one or more of the aftertreatment system devices may be maintained during a deceleration or motoring condition of operation by reducing the mass airflow to the engine.

A method and system for controlling operation of a two-stroke engine having a turbocharger includes the two-stroke engine comprising an electronically controlled exhaust valve. A throttle position sensor generates a throttle position signal corresponding to a position of a throttle plate of a throttle. A boost box is coupled to the two-stroke engine. A boost box pressure sensor is coupled to the boost box and generates a boost box pressure signal corresponding to a pressure within the boost box. A controller is coupled to the boost box pressure signal controlling a position of the electronically controlled exhaust valve in response to the boost box pressure signal and the throttle position signal.

A two-stroke engine (4) has a throttle motor (22) for driving a throttle valve (20), a fuel injection device (430) disposed in an intake system (18) including a crank chamber (420), and a control unit (24) controlling the throttle motor (22) and the fuel injection device. The two-stroke engine (4) is designed to achieve an engine rotation speed of 4,500 rpm to 7,000 rpm when the throttle valve (20) is fully open. The two-stroke engine (4) is operated with the throttle full open by the control unit (24), and a battery (8) is charged with electric power generated by a generator (6) using the two-stroke engine.

A method and system for controlling operation of a two-stroke engine having a turbocharger includes the two-stroke engine comprising an electronically controlled exhaust valve. A throttle position sensor generates a throttle position signal corresponding to a position of a throttle plate of a throttle. A boost box is coupled to the two-stroke engine. A boost box pressure sensor is coupled to the boost box and generates a boost box pressure signal corresponding to a pressure within the boost box. A controller is coupled to the boost box pressure signal controlling a position of the electronically controlled exhaust valve in response to the boost box pressure signal and the throttle position signal.

An engine unit controller (EUC) in connection with a hybrid opposed piston engine can receive real-time movement data of a crankshaft via a crank position sensor. It can simultaneously receive current data of an electric motor that partially controls the crankshaft. With the known engine constants, the EUC can determine instantaneous combustion pressure data based on the movement data and the current data. Such combustion pressure data can be used to optimize the engine's performance in real-time.

A system and method of controlling a turbocharged engine system includes receiving a boost mode selection signal and controlling the turbocharged engine system in response to the boost mode selection signal.

A control system and method relating to operation of an internal combustion engine, particularly an engine for powering an unmanned aerial vehicle. The engine has a combustion chamber and a throttle for regulating fluid flow to the combustion chamber, the throttle being operable under the control of an electronic control unit. With the control system and method there are first and second modes optionally available for operation of the engine. In the first mode the engine is operable at a throttle setting set by a request from a first remote controller (e.g. a ground-based controller) via a second on-board controller. In the second mode the engine is operable at a prescribed minimum throttle setting asserted by the electronic control unit which limits the authority of the on-board controller. The engine is caused to operate in the second mode if a particular throttle setting determined from a request of the remote controller is less than the prescribed minimum throttle setting.