Parameter identification device, parameter identification method, and computer program

A parameter identification device (10) for identifying a parameter of a target system is characterized by comprising: a first storage unit (16) for storing a first equation, which is a continuous equation, in which a first-order differential value of a first quantity including a state quantity of the system is represented by using an input value to the system and the first quantity; a second storage unit (18) that stores a second equation in which the output of the system is represented using an expanded state quantity including a state quantity and a parameter and a first-order differential value; a first calculation unit (20) that uses a first equation, a first amount in the first time step, and an input value to the system in the first time step to calculate an expansion state amount in a second time step, which is a time step next to the first time step; a second calculation unit (22) that calculates the system output in the first time step using the first equation, the second equation, the expansion stat