A power system for converting waste heat from exhaust gases of an internal combustion engine to electrical energy includes an aftertreatment assembly positioned within a first housing. The power system includes an evaporator assembly positioned within a second housing. The evaporator assembly is positioned directly adjacent the aftertreatment assembly. The evaporator assembly includes a first portion of a working fluid loop in thermal communication with a first length of an exhaust conduit that extends from the aftertreatment assembly into the second housing. The power system includes a power pack positioned longitudinally forward of the aftertreatment assembly. The power pack includes a tank, a condenser, a pump and an expander fluidly connected by a second portion of the working fluid loop. The second portion is fluidly connected to the first portion of the working fluid loop.

A cooling system for a powertrain includes: a rotating electrical machine unit including a rotating electrical machine; and a power control unit configured to drive the rotating electrical machine. The cooling system includes: a radiator configured to cool a refrigerant; a refrigerant circulation circuit configured to supply the refrigerant flowing out from the radiator to a second cooled portion via a first cooled portion; a bypass flow path bypassing the second cooled portion; a flow control valve configured to adjust the ratio of a second refrigerant flow rate to a first refrigerant flow rate; and a control device configured to control the flow control valve. The control mode of the flow control valve includes a flow rate limiting mode in which the flow control valve is controlled to adjust the ratio such that the second refrigerant flow rate becomes less than the first refrigerant flow rate.

Methods and systems are provided for controlling a temperature of an oil used for lubricating an engine of a vehicle. In one example, a method comprises controlling an oil pump to pump oil at a first pressure, a second pressure or a third pressure in order to bias an oil cooler bypass valve to a first position, a second position or a third position, respectively, as a function of engine operating conditions. In this way, oil may be selectively routed through or around the oil cooler depending on engine operating conditions, which may serve to control oil temperature in line with the operating conditions and additionally improve fuel economy by reducing a load on the oil pump when operating conditions are such that the oil pump can be bypassed.

A thermostat is provided at a connection portion between a cooling water supply passage and a bypass passage. When the temperature of the cooling water lies in a low temperature range lower than a first reference temperature, the thermostat allows introduction of the cooling water from the cooling water discharge passage into the cooling water supply passage via the bypass passage and also prevents introduction of the cooling water from the radiator into the engine via the cooling water supply passage. When the temperature of the cooling water lies in a high temperature range equal to or higher than a second reference temperature which is higher than the first reference temperature, the thermostat allows introduction of the cooling water from the radiator into the engine via the cooling water supply passage and also prevents introduction of the cooling water from the cooling water discharge passage into the cooling water supply passage via the bypass passage.

A water pump for a vehicle includes a shaft for receiving rotational power from the engine; an impeller mounted on the shaft to pump the coolant discharged from the engine; and a housing where the shaft and the impeller are embedded, disposed in a direction opposite to the direction to which the shaft is connected with respect to the impeller to have a coolant inflow passage, into which the coolant discharged from the engine flows, formed therein, disposed along the edge of the impeller to have a coolant discharge passage for discharging the coolant pumped by the impeller to the heat exchanging means formed therein, and disposed in the direction to which the shaft is connected to have a bypass passage for discharging the coolant to the engine formed therein, and the housing has a connecting passage for connecting the coolant inflow passage and the bypass passage formed therein.

An internal combustion engine includes a state determination device. The state determination device includes a storage device and an execution device. The execution device executes an acquisition process, and a determination process. The execution device executes a guard process of bringing an internal combustion engine state variable closer to an allowable range or a value within the allowable range when the internal combustion engine state variable acquired in the acquisition process is out of the predetermined allowable range. The execution device determines the state of the internal combustion engine based on the internal combustion engine state variable after the guard process in the subsequent determination process when the guard process is executed.

Methods and systems are provided for controlling a temperature of an oil used for lubricating an engine of a vehicle. In one example, a method comprises controlling an oil pump to pump oil at a first pressure, a second pressure or a third pressure in order to bias an oil cooler bypass valve to a first position, a second position or a third position, respectively, as a function of engine operating conditions. In this way, oil may be selectively routed through or around the oil cooler depending on engine operating conditions, which may serve to control oil temperature in line with the operating conditions and additionally improve fuel economy by reducing a load on the oil pump when operating conditions are such that the oil pump can be bypassed.

A thermal management system for a vehicle includes an engine cooling circuit that causes a heat medium to circulate through an engine, and an engine radiator that exchanges heat between the heat medium in the engine cooling circuit and outside air. The thermal management system for a vehicle further includes a switching device that switches between an independent mode in which the heat medium circulates respectively independently through a cooler cooling circuit and the engine cooling circuit, and a communication mode in which the cooler cooling circuit and the engine cooling circuit communicate with each other to cause the heat medium to flow between a chiller and the engine radiator; and a controller that controls an operation of the switching device to switch to the communication mode when a temperature of the heat medium in the engine cooling circuit is lower than a first heat-medium temperature.

An apparatus for controlling the flow rate of engine coolant by use of a thermostat may include a thermostat arranged in an inflow flow path for the engine coolant and a flow rate regulator arranged in a bypass flow path for the engine coolant between a cylinder head of an engine and the thermostat. The flow rate regulator regulates the flow rate of the bypass flow path such that a differential pressure of the coolant between a front end for allowing the coolant flowing from a radiator to flow into the thermostat and a rear end for allowing the coolant to be discharged from the thermostat is within a predetermined range.

A coolant circuit for a drive device. It includes a first coolant sub-circuit and a second coolant sub-circuit, in each of which a device to be temperature-controlled is arranged and which are fluidically connected to one another via at least one connecting valve, wherein at least one coolant pump is provided in each of the two coolant sub-circuits, which is designed in at least one of the coolant sub-circuits as a fluid pump having variable delivery direction. The disclosure furthermore relates to a method for operating a coolant circuit for a drive device.