PREDICTIVE DEADBEAT CONTROL OF MOTOR PHASE CURRENTS WITH MODEL MISMATCH COMPENSATION AND ADJUSTABLE CONTROL DYNAMICS

Abstract

The invention relates to a motor control device for controlling a motor current, with a predictive deadbeat control unit configured to, based on a motor current error input signal, use a model predictive control scheme for providing an output signal for controlling the motor current according to a deadbeat control scheme, where the deadbeat control scheme is characterized by minimizing the motor current error input signal within a preset time period; an interface unit configured to allow adjusting the preset time period by a user input; and an integrator unit configured to, based on the motor current error input signal, provide an integrator output that is added to the output signal for controlling the motor current with controlling a motor current, with the advantages of a predictive deadbeat control scheme while avoiding the problems present in the conventional predictive deadbeat approaches. The invention also relates to a corresponding method.

Claims

1. A motor control device for controlling a motor current, comprising: a predictive deadbeat control unit configured to, based on a motor current error input signal, use a model predictive control scheme for providing an output signal (p) for controlling the motor current according to a deadbeat control scheme, where the deadbeat control scheme is characterized by minimizing the motor current error input signal (e) within a preset time period (Ts); an interface unit configured to allow adjusting the preset time period (Ts) by a user input (u); and an integrator unit configured to, based on the motor current error input signal (e), provide an integrator output (i) that is added to the output signal (p) for controlling the motor current.

2. The motor control device according to claim 1, wherein: the integrator unit has a preset integrator gain (Ki), in particular a preset constant integrator gain, and the interface unit is configured to allow adjusting the preset integrator gain (Ki) by the user input (u).

3. The motor control device according to claim 2, wherein: the interface unit is configured to calculate and adjust the preset integrator gain (Ki) based on at least a first parameter (Ki0) contained in the user input (u).

4. The motor control device according to claim 4, wherein: the interface unit is configured to calculate and adjust the preset time period (Ts) based on at least a second parameter (Kp0) contained in the user input (u).

5. The motor control device according to claim 4, wherein: the interface unit is configured to calculate the preset time period (Ts) and/or preset integrator gain (Ki) based on the first parameter (Ki0) of the user input (u) and the second parameter (Kp0) of the user input (u) using a mathematical model of an electric motor which, quantifies a nonlinear relation between the respective parameter (Ki0, Kp0) of the user input (u) and the preset time period (Ts) and/or the preset integrator gain (Ki).

6. The motor control device according to claim 4 wherein: the first parameter (Ki0) and second parameter (Kp0) of the user input (u) represent a set of independent parameters, that include: damping ratio and settling time, or damping ratio and bandwidth, or gain margin and phase margin.

7. The motor control device according to claim 4, wherein: the user input (u) comprises only the first (Ki0) and second parameter (Kp0) or only the first (Ki0) and second parameter (Kp0) along with a specifier which represents a definition of a rise time.

8. Motor A robotic device, having the motor control device according to claim 1.

9. A method for controlling a motor current, comprising: adjusting a preset time period (Ts) for a predictive deadbeat control unit which is configured to, based on a motor model and a motor current error input signal (e), use a model predictive deadbeat control scheme for providing an output signal (p), where the predictive deadbeat control scheme is characterized by minimizing the motor current error input signal (e) within the preset time period (Ts); providing the motor current error input signal (e); using, by the predictive deadbeat control unit, the model predictive deadbeat control scheme for providing an output signal (p) for controlling the motor current; and adding an integrator output (i) provided by an integrator unit based on the motor current error input signal (e) to the output signal (p) for controlling the motor current.

Description

[0054] Exemplary embodiments are further described in the following by means of a schematic drawing.

[0055] FIG. 1 shows an exemplary embodiment of a motor control device. The motor control device 1 for controlling a motor current comprises a predictive deadbeat control unit 2 and an integrator unit 3. The predictive deadbeat control unit 2 is configured to, based on a motor current error input signal e(t), use a model predictive control scheme for providing an output signal p(t) for controlling the motor current according to a deadbeat control scheme, where the deadbeat control scheme is characterized by minimizing the motor current error input signal e(t) within a preset time period Ts. The integrator unit 3 is configured to provide an integrator output i(t) that is added to the output signal p(t) for controlling the motor current, with, in the present example, the sum signal s(t)=p(t)+i(t).

[0056] The motor control device 1 further comprises an interface unit 4 configured to allow adjusting the preset time period Ts, and, in the present example, also the preset integrator gain Ki, by a user input u(Ki0, Kp0). In the shown example, the user input comprises a first parameter Ki0 which may be used to adjust the preset integrator gain Ki and a second parameter Kp0 which may be used, preferably in conjunction with the first parameter, to adjust the preset time period Ts. In the present example, the user input u(Ki0, Kp0) only comprises these two single parameters. The interface unit 4 is, in the present example, configured to calculate the preset integrator gain Ki and the preset time period Ts based on the user input u(Ki0, Kp0) by calculating the preset time period Ts based on the second parameter Kp0 and the preset integrator gain Ki based on the calculated preset time period Ts and the first parameter Ki0 of the user input u(Ki0, Kp0). Alternatively, the preset integrator gain Ki may, for instance, equal the first parameter Ki0, and the preset time period Ts may be calculated by the interface unit 4 using a mathematical model of the electric motor which is to be controlled by the sum signal s(t) based on only the second parameter Kp0 of the user input u(Ki0, Kp0).