Each of a plurality of specified chopper cells which are some of a plurality of chopper cells included in each leg circuit in a power conversion device is configured as a full bridge. A control device controls operations of first and second switching elements of each specified chopper cell based on a circulating current which circulates through each leg circuit. The control device controls operations of third and fourth switching elements of each specified chopper cell based on a voltage of a capacitor of the specified chopper cell.

A method operates an inverter by driving respective switching means of the bridge arms using pulse width modulation with a temporally changeable duty cycle such that voltages between the bridge connections have a temporally predefined profile. The respective switching means of the bridge arms are driven with flat-top modulation for particular angular ranges of a respective fundamental oscillation. A respective duty cycle for the respective switching means of the bridge arms is selected such that, during a respective period of the pulse width modulation, at least two shunt resistors always perform their measurement function for a minimum time.

A converter device is provided. The converter device includes a filter circuit, a DC link and an active rectifier interconnected between the filter circuit and the DC link. A method for determining at least one parameter (b) of the filter circuit is also provided. The method includes switching the active rectifier into an active state, where a first active rectifier leg connects a first phase of the filter circuit with a positive side of the DC link and a second active rectifier leg connects a second phase of the filter circuit with a negative side of the DC link; determining a time series (y) of current values by measuring a current through the filter circuit; and determining the at least one parameter (b) of the filter circuit by calculating a best fit of the at least one parameter (b) from a difference equation of the filter circuit.

A converter device is provided. The converter device includes a filter circuit, a DC link and an active rectifier interconnected between the filter circuit and the DC link. A method for determining at least one parameter (b) of the filter circuit is also provided. The method includes switching the active rectifier into an active state, where a first active rectifier leg connects a first phase of the filter circuit with a positive side of the DC link and a second active rectifier leg connects a second phase of the filter circuit with a negative side of the DC link; determining a time series (y) of current values by measuring a current through the filter circuit; and determining the at least one parameter (b) of the filter circuit by calculating a best fit of the at least one parameter (b) from a difference equation of the filter circuit.

A method for switching off power semiconductor switches in a bridge circuit having first through sixth power semiconductor switches. The method includes a switch-off process for establishing a final switch configuration in which all power semiconductor switches in the bridge circuit are in a switched-off state. Over the course of the switch-off process, a switch configuration is established in which the fifth power semiconductor switch and the sixth power semiconductor switch are concurrently in a switched-on state, while the first power semiconductor switch and the fourth power semiconductor switch are in a switched-off state. Also disclosed is a bridge circuit having a control circuit configured to carry out such a method. In addition, an inverter that includes at least one bridge circuit of this type is also provided.

A method for switching off power semiconductor switches in a bridge circuit having first through sixth power semiconductor switches. The method includes a switch-off process for establishing a final switch configuration in which all power semiconductor switches in the bridge circuit are in a switched-off state. Over the course of the switch-off process, a switch configuration is established in which the fifth power semiconductor switch and the sixth power semiconductor switch are concurrently in a switched-on state, while the first power semiconductor switch and the fourth power semiconductor switch are in a switched-off state. Also disclosed is a bridge circuit having a control circuit configured to carry out such a method. In addition, an inverter that includes at least one bridge circuit of this type is also provided.

A normal workflow including a plurality of steps may be defined by exemplary systems and methods for use in preparing a treatment, performing a treatment, and performing post-treatment processes. A user may be guided by one or more workflow affordances to indicate where and how to use a graphical user interface to follow the normal workflow. When a user deviates from the normal workflow, one or more deviation workflow affordances may be displayed on the graphical user interface to guide a user back to the normal workflow.

Accordingly, the embodiments herein provide a hybrid modular multilevel converter. The hybrid modular multilevel converter includes one or more chain links, one or more high voltage switches and a plurality of inductors. The one or more chain links are formed by sub modules. The one or more high voltage switches are formed by semi-controlled devices or fully controlled or any other suitable semiconductor devices. The plurality of inductors are arranged in the one or more chain links to limit circulating current among the one or more chain links. The one or more chain links are configured to enhance a power handling capability of the hybrid modular multilevel converter.

A capacitor has a known capacitance value for filtering the ripple current of the DC voltage bus. A first modulation index estimator is configured to estimate a first modulation index of the first inverter. A second modulation index estimator configured to estimate a second modulation index of the second inverter. A current estimator is configured to estimate an interleaving phase shift angle associated with a respective one of a set of inverters based on the known capacitance value of the capacitor, the estimated first modulation index, the estimated second modulation index, the first control input and the second control input.

A capacitor has a known capacitance value for filtering the ripple current of the DC voltage bus. A first modulation index estimator is configured to estimate a first modulation index of the first inverter. A second modulation index estimator configured to estimate a second modulation index of the second inverter. A current estimator is configured to estimate an interleaving phase shift angle associated with a respective one of a set of inverters based on the known capacitance value of the capacitor, the estimated first modulation index, the estimated second modulation index, the first control input and the second control input.