Hybrid electric secondary power and battery charging architecture and control system

An aircraft hybrid electrical system comprising:

• an electric power generating system in signal communication with a high spool of a thermal combustion engine and a low spool of the thermal combustion engine, wherein the electric power generating system comprises:
• a first motor generator configured to generate a first alternating current (AC) voltage in response to operating the high spool;
• a first motor controller configured to rectify the first AC voltage to generate a first direct current (DC) voltage;
• a second motor generator configured to generate a second AC voltage in response to operating the high spool;
• and
• a second motor controller configured to rectify the second AC voltage to generate a second DC voltage;
• a battery system including a battery in signal communication with the electric power generating system to receive the DC voltage and in signal communication with the secondary power system to deliver a DC battery voltage, the battery system configured to interchange the battery of a first type with a second battery of a second type different from the battery of the first type;
• a secondary power system in signal communication with the electric power generating system;
• the secondary power system configured to convert at least one of the DC voltage and the DC battery voltage into a converted DC voltage configured to drive an aircraft load;
• and
• a system controller in signal communication with the electric power generating system, the secondary power system, and the battery, the system controller configured to monitor the DC voltage, the DC battery voltage, and the converted DC voltage, and to control the motor controller and rectifier to adjust a voltage of the DC voltage,
• wherein the system controller is configured to store a first charging profile corresponding to the battery of the first type and a second charging profile different corresponding to the second battery of the second type, the system controller configured to monitor a charge capacity of the battery and selectively operate in a current charge mode and a voltage charge mode to charge the battery of the first type according to the first charging profile,
• wherein the system controller is configured to invoke the current charge mode in response to detecting the charge capacity falls below a charge capacity threshold and is configured to invoke the voltage charge mode in response to detecting the charge capacity reaches a target value,
• wherein the controller is configured to detect that the battery of the first type is interchanged with the second battery of the second type, and is configured to selectively operate in a current charge mode and a voltage charge mode to charge the second battery of the second type according to the second charging profile, and
• wherein the controller is configured to transition into the voltage charge mode in response to detecting the charge capacity reaches a target value to maintain the battery at a constant target cell voltage.

A method of charging a battery included in an aircraft hybrid electrical system comprising, the method comprising:

• installing a battery of a first type in a battery system of the aircraft hybrid electrical system;
• generating, by an electric power generating system, an electric power based on operation of a thermal combustion engine;
• rectifying, by a motor controller and rectifier, the electric power to generate a DC power;
• delivering the electric power to the battery of the first type;
• outputting DC battery power from the battery of the first type to a secondary power system;
• converting, by the secondary power system, the DC battery power into a converted DC power;
• monitoring the DC power, the DC battery power, and the converted DC power by a system controller, and controlling the motor controller and rectifier using the system controller to adjust the DC power;
• selecting, by the system controller, a first charging profile corresponding to the battery of the first type;
• monitoring, by the system controller, a charge capacity of the battery of the first type;
• invoking, by the system controller, a current charge mode defined by the first charging profile in response to detecting the charge capacity falling below a charge capacity threshold to increase the charge capacity of the battery;
• switching, by the system controller, from the current charge mode to a voltage charge mode defined by the first charging profile in response to detecting the charge capacity reaches a target value to continue charging the battery so that the charge capacity reaches a full capacity;
• detecting, by the system controller, that the battery of the first type is interchanged with a second battery of a second type;
• invoking, by the system controller, a current charge mode defined by the second charging profile in response to detecting the charge capacity of the second battery is below a charge capacity threshold so as to increase the charge capacity of the second battery;
• switching, by the system controller, from the current charge mode to a voltage charge mode defined by the second charging profile in response to detecting the charge capacity of the second battery reaches a target value to continue charging the second battery so that the charge capacity of the second battery reaches a full capacity while maintaining the battery at a constant target cell voltage.