Telefonaktiebolaget Lm Ericsson (publ)

Anders Kullman

Jonas Malmberg

Magnus Karlsson

Henrik Borgengren

Oscar Persson

Mikael Appelberg

Fredrik Wahledow

Mikael Hàkan Appelberg

A control circuit for a switched mode power supply (SMPS) has an input voltage reference voltage generator arranged to receive a signal indicative of an input voltage of the SMPS and is arranged to generate a reference signal directly proportional to the input voltage. An error signal generator of the control circuit is arranged to receive a signal indicative of an output voltage of the SMPS and arranged to generate an error signal based on the reference signal generated by the input reference voltage generator and based on the output voltage of the SMPS. A duty cycle control signal generator of the control circuit is arranged to generate a control signal, to control the duty cycle of the SMPS, in dependence upon the error signal.

Controlling a switched mode power supply with maximised power efficiency

A digital control unit generates a control signal to control a duty cycle of a switched mode power supply such that a faster response to an input voltage transient is achieved. The digital control unit comprises a feedback compensator, a feed forward compensator, a transient detector, and a controller. The transient detector receives a signal indicative of the input voltage of the switched mode power supply and detects transients on the received signal. The feedback compensator receives a signal indicative of the output voltage of the switched mode power supply and adjusts the control signal. The feed forward compensator receives a signal indicative of the input voltage of the switched mode power supply, performs a relatively fast, but coarse, adjustment of the control signal, and then performs a more accurate, but relatively slow, adjustment of the control signal.

Voltage feed-forward compensation and voltage feedback compensation for switched mode power supplies

To reduce power loss in an intermediate bus architecture power system, embodiments of the present invention provide an intermediate bus converter which converts an input voltage to an intermediate bus voltage using a converting unit; receives a signal indicative of an output of a converting unit; determines an intermediate bus voltage to reduce power loss in dependence upon the signal indicative of an output of the converting unit; generates a control signal to control the converting unit to convert the input voltage to the determined intermediate bus voltage; and generates an intermediate bus voltage in dependence upon the control signal.

Control of dynamic bus voltage in an intermediate bus architecture power system

A switching delay controller is configured to control a switching delay between the switching of first and second switching elements in a switched mode power supply. The switched mode power supply generates a feedback signal indicative of a difference between an output of the switched mode power supply and a reference for the output, and switches the first and second switching elements to convert an input voltage into an output voltage based on the feedback signal. The switching delay controller includes a switching delay calculator operable to cause a change of the switching delay for at least one switching cycle of the switched mode power supply, and a feedback signal monitor operable to monitor the feedback signal and determine a change in the feedback signal in response to the change of the switching delay by the switching delay calculator.

Switching delay controller for a switched mode power supply

A power converter system disclosed herein includes first and second voltage converting modules, for converting input current to output voltage, and a current share controller configured to establish a master-slave relationship between the first and second voltage converting modules. As a result, one of the first and second voltage converting modules acts as a master module, and the other acts as a slave module. The first and second voltage converting modules are arranged to operate in a current share configuration so as to share a load of the power converter system. The master module determines its output current and sends a signal indicative of its output current to the slave module via at least one signaling line connecting the master and modules to the current share controller. The slave module adjusts its output current in dependence on the signal from the master module.

Current share configuration in a power converter system

An isolated switched mode power supply (SMPS) is disclosed. The SMPS comprises a switching controller to generate start-up and operational switching control signals. The SMPS further includes a transformer, having a primary winding, and a full-bridge drive circuit to drive the primary winding. The full-bridge drive circuit comprises a first switching element, a boot-strap dnving circuit, and a second switching element. The switching controller is further used to start up isolated SMPS by determining a duty cycle for operational control signals and generating the start-up switching control signals.

Start-up procedure for an isolated switched mode power supply

A switched mode power supply (SMPS) comprising a feedback unit, voltage feed forward (VFF) compensation signal generator and a transient detector. A VFF compensation signal is only applied to the output of the feedback unit when a transient is detected by the transient detector on the input voltage of the SMPS, thereby saving power and computation time. The transient detector comprises a first comparator to detect that a positive transient has occurred if a difference signal is greater than a positive threshold level; a second comparator to determine if the difference signal is within a predetermined range of positive values and output a result that indicates if the difference signal is within the predetermined range of positive values; and a first calculator to detect that a positive transient has occurred if, out of a first predetermined number of consecutive results of the output of the second comparator, there is at least a second predetermined number of results indicating that the difference signal is within the predetermined range of positive values. The transient detector comprises further features for similarly detecting a negative transient.

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Kalmar, Sweden

Anders Kullman