Technical field

The present disclosure relates to a voltage conversion apparatus, method and a computer program product for generating a predefined alternating current voltage output.

Background art

A traditional linear transformer is a passive electrical device that is used for e.g. increasing a low alternating current to a high alternating current, or for decreasing a high alternating current to a low alternating current. Typically, a high alternating current is decreased to a low alternating current and then rectified to a direct current to be used for powering e.g. electronic devices. Traditional linear transformers are often bulky and heavy. A power supply that is more energy efficient compare to the traditional transformer, and that is used for powering electronic devices, is the smaller and lighter switched-mode power supply. The switched-mode power supply is often used to transform a high alternating current a low rectified direct current to be used for powering electronic devices.

Summary

The present disclosure is directed to transforming an alternating current at a higher voltage to an alternating current at a lower voltage. Historically a linear transformer is designed to generate a predefined alternating current voltage output based on a certain alternating current voltage input. This means that in order to generate a predefined alternating current voltage output the linear transformer has to be designed for the certain alternating current voltage input, i.e. the supply alternating current voltage, which may be different in different countries. In an example, in the U.S. the supply alternating current voltage is typically 110 volts, while in Europe the supply alternating current voltage is typically 240 volts. One problem with the current linear transformers is that they are tailor-made dependent on the alternating current voltage input in order to provide the predefined alternating current voltage output, and hence a linear transformer that is designed for Europe cannot be installed and used in the U.S. and the other way around.

The dynamic characteristics of an alternating current is desired for control and surveillance of e.g. electrical control systems compare to a the non-dynamic characteristics of a direct current. It is further desired to generate a predefined alternating current voltage output with a predefined frequency. One reason is that many safety signals, in e.g. an electrical control system, are using the fact that it is an alternating current with a predefined frequency, e.g. an alternating current that switches from positive to negative 50 times per second, i.e. 50Hz, that is used in the electrical control system. In an example, a computer program may be configured to operate based on a predefined frequency of the alternating current. A further problem is hence then that alternating current voltage input has different frequencies in different countries. As an example, in the U.S. the frequency of the alternating current voltage input is typically 60 Hz while in Europe the frequency of the alternating current voltage input is typically 50 Hz.

The inventor has identified that there is a need for generating a predefined alternating current output with a predefined frequency, as output from a voltage conversion apparatus, that is independent of the alternating current input, within a predefined alternating current voltage range, and independent of the frequency of the alternating current voltage input.

It is an object of the present disclosure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages in the prior art and solve at least the above mentioned problems. In this disclosure, the inventor suggests a voltage conversion apparatus that can be used in different parts of the World for generating a stable predefined alternating current voltage output with a predefined frequency.

According to a first aspect there is provided a voltage conversion apparatus for generating a predefined alternating current voltage output using any alternating current voltage input, within a predefined alternating current voltage range. The voltage conversion apparatus comprises an alternating current to direct current converter unit configured to convert an alternating current input to a positive direct current output, a Switching Mode Power Supply unit connected to the alternating current to direct current converter unit configured to receive the positive direct current as input on a first side and output a positive direct current power rail and output a negative direct current power rail on a second side of the Switching Mode Power Supply unit. The voltage conversion apparatus further comprises a switching amplifier unit, connected to the positive direct current power rail and to the negative direct current power rail on the second side of the Switching Mode Power Supply unit, and a signal generator unit configured to supply the switching amplifier unit with a sinus shaped signal at a certain frequency for providing a predefined alternating current voltage output from the voltage conversion apparatus.

One advantage with this aspect is that the generation of the predefined alternating current voltage output is independent on the alternating current input voltage. A further advantage with this aspect is that signal generator unit provides the switching amplifier unit with a sinus shaped signal at a certain frequency.

According to some embodiments, the sinus shaped signal provided by the signal generator unit is a sinus shaped signal at a predefined frequency for setting the switching amplifier unit to output a desired predefined alternating current voltage with the predefined sinus shaped signal frequency.

One advantage with this embodiment is that a desired predefined alternating current voltage output with a sinus shaped signal at a desired frequency can be provided.

According to some embodiments, the sinus shaped signal provided by the signal generator unit is used for setting the amplification of the switching amplifier unit to output a desired predefined alternating current voltage.

One advantage with this embodiment is that a desired predefined alternating current voltage output can be provided by using a certain amplitude of the signal generated by the signal generator unit.

According to some embodiments, the switching amplifier unit is configured to output a desired predefined alternating current voltage output with a desired sinus shaped signal frequency.

One advantage with this embodiment is that a stable predefined alternating current voltage output with a desired sinus shaped signal frequency can be obtained from the output of the voltage conversion apparatus independent of the alternating current voltage input to the the voltage conversion apparatus and independent on the sinus shaped signal frequency input to the voltage conversion apparatus. According to some embodiments, the voltage conversion apparatus further comprises a processing circuitry configured to control the signal generator unit to generate a sinus shaped signal at a certain frequency.

One advantage with this embodiment is that the signal generator can be controlled by the processing circuitry for generating a desired predefined alternating current voltage output with a desired predefined sinus shaped signal frequency.

According to some embodiments, the processing circuitry is configured to determine an input sinus shaped signal frequency of the voltage conversion apparatus, and/or determine an output sinus shaped signal frequency of the voltage conversion apparatus.

One advantage with this embodiment is that the signal generator can be further controlled for generating a stable desired predefined alternating current voltage output with a desired sinus shaped signal frequency.

According to some embodiments, the processing circuitry is configured to control the signal generator unit to output a sinus shaped signal to the switching amplifier unit that has the same sinus shaped signal frequency as the input sinus shaped signal frequency of the voltage conversion apparatus, or control the signal generator unit to output a sinus shaped signal to the switching amplifier unit that is maintained at a predefined frequency independent of the input sinus shaped signal frequency.

One advantage with this embodiment is that the signal generator unit can be controlled to output the same sinus shaped signal frequency as the input sinus shaped signal frequency. Another advantage with this embodiment is that the signal generator unit can also be controlled to output a predefined sinus shaped signal frequency.

According to some embodiments, the processing circuitry is configured to adjust the signal generator unit to output a sinus shaped signal frequency to the switching amplifier unit for generating a desired sinus shaped signal frequency output of the voltage conversion apparatus.

One advantage with this embodiment is that the signal generator unit can be adjusted in order to maintain or generate a stable desired sinus shaped signal frequency output.

According to some embodiments, the processing circuitry is configured to set a predetermined output sinus shaped signal frequency of the voltage conversion apparatus as indicative of a warning, and determine the output sinus shaped signal frequency of the voltage conversion apparatus and in accordance with a determination that the output sinus shaped signal frequency corresponds to the predetermined output sinus shaped signal frequency indicative of a warning, output a notification signal indicative of a warning.

One advantage with this embodiment is that with a notification signal indicative of a warning, the operation of the voltage conversion apparatus can be supervised.

According to some embodiments, the voltage conversion apparatus further comprises a frequency determination unit connected to the input to the alternating current to direct current converter unit for determining the input sinus shaped signal frequency to the voltage conversion apparatus and/or a frequency determination unit connected to the output of the switching amplifier unit for determining the output sinus shaped signal frequency of the voltage conversion apparatus.

One advantage with this embodiment is that the current sinus shaped signal frequency can be determined and be used for controlling the operation of the voltage conversion apparatus.

According to a second aspect there is provided a method for generating a predefined alternating current voltage output of a voltage conversion apparatus using any alternating current voltage, within a predefined alternating current voltage range, as input to the voltage conversion apparatus, the method comprising the step of determining an input sinus shaped signal frequency of the voltage conversion apparatus, and/or the step of determining the output sinus shaped signal frequency of the voltage conversion apparatus.

One advantage with this embodiment is that with knowledge of the input sinus shaped signal frequency of the voltage conversion apparatus, and/or the output sinus shaped signal frequency of the voltage conversion apparatus, the signal generator can be further controlled by the processing circuitry for generating a stable desired predefined alternating current voltage output with a desired predefined sinus shaped signal frequency.

According to some embodiments, the method further comprises the step of controlling a signal generator unit to output a sinus shaped signal to a switching amplifier unit that has the same sinus shaped signal frequency as the input sinus shaped signal frequency of the voltage conversion apparatus, the step of or controlling the signal generator unit to output a sinus shaped signal to the switching amplifier unit that is maintained at a predefined frequency independent of the input sinus shaped signal frequency. One advantage with this embodiment is that the signal generator unit can be controlled to output a predefined alternating current voltage output from the voltage conversion apparatus with the same sinus shaped signal frequency as the input sinus shaped signal frequency of the voltage conversion apparatus for e.g. an electrical control system configured for the specific sinus shaped signal frequency according to the alternating current voltage standard in that specific country. Another advantage with this embodiment is that the signal generator unit can also be controlled to output a predefined alternating current voltage output from the voltage conversion apparatus with a predefined sinus shaped signal frequency for e.g. maintain a correct operation of an electrical control system that configured to operate according to a specific sinus shaped signal frequency independent on the alternating current voltage standard in the country where the voltage conversion apparatus is used.

According to some embodiments, the method further comprises the step of adjusting the signal generator unit to output a sinus shaped signal to the switching amplifier unit for generating a desired sinus shaped signal frequency output of the output of the switching amplifier unit.

One advantage with this embodiment is that with knowledge of the output sinus shaped signal frequency of the voltage conversion apparatus, the signal generator unit can be adjusted in order to maintain or generate a stable desired sinus shaped signal frequency output of the voltage conversion apparatus.

According to some embodiments, the method further comprises the step of setting a predetermined output sinus shaped signal frequency of the output of the switching amplifier unit as indicative of a warning; and the step of determining the output sinus shaped signal frequency of the voltage conversion apparatus, and in accordance with a determination that the output sinus shaped signal frequency corresponds to the predetermined output sinus shaped signal frequency indicative of a warning, outputting a notification signal indicative of a warning.

One advantage with this embodiment is that with a notification signal indicative of a warning, the operation of the voltage conversion apparatus can be supervised.

According to a third aspect there is provided a computer program product comprising a non-transitory computer readable medium, having thereon a computer program comprising program instructions, the computer program being loadable into a processing circuitry and configured to cause execution of the method when the computer program is run by the at least one processing circuitry.

Effects and features of the second and third aspects are to a large extent analogous to those described above in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second and third aspects.

The present disclosure will become apparent from the detailed description given below. The detailed description and specific examples disclose preferred embodiments of the disclosure by way of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the disclosure.

Hence, it is to be understood that the herein disclosed disclosure is not limited to the particular component parts of the device described or steps of the methods described since such device and method may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only, and is not intended to be limiting. It should be noted that, as used in the specification and the appended claim, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements unless the context explicitly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

Brief of the

The above objects, as well as additional objects, features and advantages of the present disclosure, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of example embodiments of the present disclosure, when taken in conjunction with the accompanying drawings.

Figure la illustrates an example circuit board diagram of the voltage conversion apparatus according to an embodiment of the present disclosure.

Figure lb illustrates an example circuit board diagram of the voltage conversion apparatus according to an embodiment of the present disclosure. Figure 2 illustrates a flow chart of the method steps according to the second aspect of the disclosure.

Figure 3 illustrates a computer program product according to the third aspect of the disclosure.

Detailed description

The present disclosure will now be described with reference to the accompanying drawings, in which preferred example embodiments of the disclosure are shown. The disclosure may, however, be embodied in other forms and should not be construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.

Figure la illustrates an example circuit board diagram of the voltage conversion apparatus according to an embodiment of the present disclosure. The arrangement of the components of the example circuit board diagram can be different dependent on desired design.

The first aspect of this disclosure, as illustrated in Figure la, shows a voltage conversion apparatus 100 for generating a predefined alternating current voltage output VAC- p-out using any alternating current voltage input, within a predefined alternating current voltage range. According to some embodiments the predefined alternating current voltage output VAC-p-out is 24VAC as illustrated in Figure lb. According to some embodiments any alternating current voltage input, within a predefined alternating current voltage range, is any alternating current voltage input within the alternating current voltage range 85-285 VAC as illustrated in Figure lb. According to some embodiments the voltage conversion apparatus 100 is configured to generate a predefined alternating current voltage output VAC-p-out using an alternating current voltage input that is varying over time, e.g. due to an unstable power grid network.

The voltage conversion apparatus 100 comprises an alternating current to direct current converter unit 10 configured to convert an alternating current input to a positive direct current +DC output. According to some embodiments the alternating current to direct current converter unit 10 is configured to convert an alternating current input of 110 VAC to a positive direct current +DC output of 110 DC as illustrated in Figure lb. The voltage conversion apparatus 100 further comprises a Switching Mode Power Supply unit 20 connected to the alternating current to direct current converter unit 10. According to some embodiments the Switching Mode Power Supply unit 20 comprising a Switching Mode Power Supply controller 21 and a Switching Mode Power Supply isolation transformer 22 as illustrated in Figure la. According to some embodiments the Switching Mode Power Supply controller 21 is an electric power supply that incorporates a switching regulator, that rapidly switch on and off, to convert electrical power. An advantage with the Switching Mode Power Supply unit 20 compare to a traditional linear transformer is that the power conversion efficiency is higher. Another advantage is that the Switching Mode Power Supply unit 20 is lighter and smaller compare to a traditional linear transformer.

The Switching Mode Power Supply unit 20 is configured to receive the positive direct current +DC as input on a first side A, as illustrated in Figure la, and output a positive direct current power rail +DCpr and output a negative direct current power rail -DCpr on a second side B, as illustrated in Figure la, of the Switching Mode Power Supply unit 20. According to some embodiments the Switching Mode Power Supply controller 21 is configured to convert electrical power to maintain a desired predefined positive direct current power rail +DCpr output, and a desired predefined negative direct current power rail -DCpr output from the Switching Mode Power Supply isolation transformer 22.

In an example, as illustrated in Figure lb, the positive direct current power rail +DCpr is 40V DC and the negative direct current power rail -DCpr is -40V DC.

The voltage conversion apparatus 100 further comprises a switching amplifier unit 30, connected to the positive direct current power rail +DCpr and to the negative direct current power rail -DCpr on the second side B of the Switching Mode Power Supply unit, as illustrated in Figure la. According to some embodiments the switching amplifier unit 30 is a class D- amplifier. According to some embodiments the switching amplifier unit 30 comprises at least one amplifying device that operates as an electronic switch. According to some embodiments the at least one amplifying device of the switching amplifier unit 30 is a transistor. According to some embodiments the at least one amplifying device of the switching amplifier unit 30 is a metal-oxide-semiconductor field-effect transistor, MOSFET. According to some embodiments the switching amplifier unit 30 is configured to operate by switching back and forth between the positive direct current power rail +DCpr and the negative direct current power rail -DCpr that are supplied to the switching amplifier unit 30. The voltage conversion apparatus 100 further comprises a signal generator unit 40 configured to supply the switching amplifier unit 30 with a sinus shaped signal at a certain frequency for providing a predefined alternating current voltage VAC-p-out output from the voltage conversion apparatus 100.

One advantage with this first aspect is that the generation of the predefined alternating current voltage output is independent on the alternating current input voltage. A further advantage with this first aspect is that signal generator unit provides the switching amplifier unit with a sinus shaped signal at a certain frequency.

According to some embodiments the sinus shaped signal is mathematical curve that describes a smooth periodic oscillation with a certain amplitude and a certain frequency. According to some embodiments the sinus shaped signal is a square wave signal that describes a periodic oscillation with a certain amplitude and a certain frequency. According to some embodiments the sinus shaped signal is a fluctuating signal that with an average curve propagation that describes a periodic oscillation with a certain amplitude and a certain frequency. According to some embodiments the sinus shaped signal is a sine wave shaped signal or sinusoid shaped signal.

According to some embodiments the sinus shaped signal provided by the signal generator unit 40 is a sinus shaped signal at a predefined frequency f-pre for setting the switching amplifier unit to output a desired predefined alternating current voltage VAC-p-out with the predefined sinus shaped signal frequency f-pre. In the example illustration in Figure lb, the predefined alternating current voltage VAC-p-out is 24VAC and the predefined sinus shaped signal frequency f-pre is 50Hz.

One advantage with this embodiment is that a desired predefined alternating current voltage output VAC-p-out with a sinus shaped signal at a desired frequency can be provided.

According to some embodiments the sinus shaped signal provided by the signal generator unit 40 is used for setting the amplification of the switching amplifier unit 30 to output a desired predefined alternating current voltage VAC-p-out. According to some embodiments the amplitude of the sinus shaped signal provided by the signal generator unit 40 is used for setting the amplification of the switching amplifier unit 30 to output a desired predefined alternating current voltage VAC-p-out. According to some embodiments the desired predefined alternating current voltage VAC-p-out from the voltage conversion apparatus 100 is generated based on the absolute current value of the positive direct current power rail +DCpr and to the negative direct current power rail -DCpr, and the amplitude of the sinus shaped signal provided by the signal generator unit 40.

One advantage with this embodiment is that a desired predefined alternating current voltage output VAC-p-out can be provided by using a certain amplitude of the signal generated by the signal generator unit 40.

According to some embodiments the switching amplifier unit 30 is configured to output a desired predefined alternating current voltage output VAC-p-out with a desired sinus shaped signal frequency.

One advantage with this embodiment is that a stable predefined alternating current voltage output VAC-p-out with a desired sinus shaped signal frequency can be obtained from the output of the voltage conversion apparatus 100 independent of the alternating current voltage input VAC-in to the the voltage conversion apparatus 100 and independent on the sinus shaped signal frequency input f-in to the voltage conversion apparatus 100.

According to some embodiments the voltage conversion apparatus 100 further comprises a processing circuitry 101 configured to control the signal generator unit 40 to generate a sinus shaped signal at a certain frequency. According to some embodiments, the processing circuitry 101 is a processing circuitry that is integrated in the voltage conversion apparatus 100. According to some embodiments, the processing circuitry 101 is a processing circuitry of an electronic device configured to be operatively connected to the voltage conversion apparatus 100. According to some embodiments, the processing circuitry 101 is a processing circuitry of a remote server configured to be operatively connected to the voltage conversion apparatus 100 via a communication network.

One advantage with this embodiment is that the signal generator unit 40 can be controlled by the processing circuitry 101 for generating a desired predefined alternating current voltage output VAC-p-out with a desired predefined sinus shaped signal frequency.

According to some embodiments, processing circuitry 101 is further configured to control the operation of the Switching Mode Power Supply unit 20. According to some embodiments, processing circuitry 101 is further configured to control the operation of the Switching Mode Power Supply controller 21 of the Switching Mode Power Supply unit 20.

According to some embodiments the processing circuitry 101 is configured to determine an input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, and/or determine an output sinus shaped signal frequency f-out of the voltage conversion apparatus 100.

One advantage with this embodiment is that with knowledge of the input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, and/or the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100, the signal generator 40 can be further controlled by the processing circuitry 101 for generating a stable desired predefined alternating current voltage output VAC-p-out with a desired sinus shaped signal frequency.

According to some embodiments the processing circuitry 101 is configured to control the signal generator unit 40 to output a sinus shaped signal to the switching amplifier unit 30 that has the same sinus shaped signal frequency as the input sinus shaped signal frequency f- in of the voltage conversion apparatus 100, or control the signal generator unit 40 to output a sinus shaped signal to the switching amplifier unit 30 that is maintained at a predefined frequency f-pre independent of the input sinus shaped signal frequency f-in.

One advantage with this embodiment is that the signal generator unit 40 can be controlled to output a predefined alternating current voltage output VAC-p-out from the voltage conversion apparatus 100 with the same sinus shaped signal frequency as the input sinus shaped signal frequency f-in of the voltage conversion apparatus 100 for e.g. an electrical control system configured for the specific sinus shaped signal frequency according to the alternating current voltage standard in that specific country.

Another advantage with this embodiment is that the signal generator unit can also be controlled to output a predefined alternating current voltage output VAC-p-out from the voltage conversion apparatus 100 with a predefined sinus shaped signal frequency f-pre to e.g. maintain a correct operation of an electrical control system that is configured to operate according to a specific sinus shaped signal frequency independent on the alternating current voltage standard in the country where the voltage conversion apparatus is used.

According to some embodiments the processing circuitry 101 is configured to adjust the signal generator unit 40 to output a sinus shaped signal frequency to the switching amplifier unit 30 for generating a desired sinus shaped signal frequency output of the voltage conversion apparatus 100. According to some embodiments the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100 is fed back to the processing circuitry 101 for determining the operation of the signal generator unit 40. One advantage with this embodiment is that with knowledge of the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100, the signal generator unit 40 can be adjusted in order to maintain or generate a stable desired sinus shaped signal frequency output of the voltage conversion apparatus 100.

According to some embodiments the processing circuitry 101 is configured to set a predetermined output sinus shaped signal frequency of the voltage conversion apparatus 100 as indicative of a warning f-warn and determine the output sinus shaped signal frequency f- out of the voltage conversion apparatus 100, and in accordance with a determination that the output sinus shaped signal frequency f-out corresponds to the predetermined output sinus shaped signal frequency indicative of a warning f-warn, output a notification signal indicative of a warning.

According to some embodiments the notification signal indicative of a warning is at least any of a sound, light or tactile signal by a warning signal device operatively connected to the voltage conversion apparatus 100. According to some embodiments the notification signal indicative of a warning is sent via a communication network to a remote electronic device operatively connected to the voltage conversion apparatus 100. According to some embodiments the notification signal indicative of a warning is used to cease operation of an electronic device operatively connected to the voltage conversion apparatus 100.

One advantage with this embodiment is that with knowledge of the output sinus shaped signal frequency f-out is e.g. changing from a desired output sinus shaped signal frequency of the voltage conversion apparatus 100, this can be an indication of e.g. overheating or malfunction of the voltage conversion apparatus 100, and by outputting a notification signal indicative of a warning, the operation of the voltage conversion apparatus 100 can be supervised which in turn eliminates further damage or faults due to an undesired output sinus shaped signal frequency.

In the example as illustrated in Figure lb, the desired output sinus shaped signal frequency of the voltage conversion apparatus 100 is 50Hz. In the example the predetermined output sinus shaped signal frequency of the voltage conversion apparatus 100 indicative of a warning f-warn is set to 45Hz. In the example, the voltage conversion apparatus 100 is overheated, and in particular the signal generator unit 40 of the voltage conversion apparatus 100 is overheated, that causes a fault operation of the signal generator unit 40 which causes the voltage conversion apparatus 100 to output an undesired output sinus shaped signal frequency. When the output sinus shaped signal frequency f-out corresponds to the predetermined output sinus shaped signal frequency indicative of a warning f-warn, in the example 45 Hz, a notification signal indicative of a warning is generated, "Warning!".

According to some embodiments the voltage conversion apparatus 100 further comprises a frequency determination unit 50a connected to the input to the alternating current AC to direct current DC converter unit for determining the input sinus shaped signal frequency f-in to the voltage conversion apparatus 100 and/or a frequency determination unit 50b connected to the output of the switching amplifier unit 30 for determining the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100.

According to some embodiments the frequency determination unit 50a and/or the frequency determination unit 50b connected are/is operatively connected to the processing circuitry 101.

One advantage with this embodiment is that the current sinus shaped signal frequency can be determined and be used for controlling the operation of the voltage conversion apparatus 100 to e.g. provide a predefined alternating current voltage output from the voltage conversion apparatus 100.

Figure lb illustrates an example voltage conversion apparatus 100 with both a frequency determination unit 50a connected to the input to the alternating current AC to direct current DC converter unit 10, and a frequency determination unit 50b connected to the output of the switching amplifier unit 30. In the example illustration the frequency determination units 50a and 50b are operatively connected to the processing circuitry 101.

In the example illustration of Figure lb, the processing circuitry 101 is operatively connected to the frequency determination units 50a, 50b and to the signal generator unit 40, and the Switching Mode Power Supply controller 21. According to some embodiments the processing circuitry 101 is configured to determine an input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, and/or determine an output sinus shaped signal frequency f-out of the voltage conversion apparatus 100, and to adjust the signal generator unit 40 to output a sinus shaped signal frequency to the switching amplifier unit 30 for generating a desired sinus shaped signal frequency output of the voltage conversion apparatus 100, and further configured to control the Switching Mode Power Supply controller 21 to convert electrical power to maintain a desired predefined positive direct current power rail +DCpr output, and a desired predefined negative direct current power rail -DCpr output from the Switching Mode Power Supply isolation transformer 22, for providing a predefined alternating current voltage (VAC-p-out) output from the voltage conversion apparatus (100).

The second aspect of this disclosure shows a method for generating a predefined alternating current voltage output VAC-p-out of a voltage conversion apparatus 100 using any alternating current voltage, within a predefined alternating current voltage range, as input to the voltage conversion apparatus 100.

Figure 2 illustrates a flow chart of the method steps according to the second aspect of the disclosure.

The method comprising the step of Sla determining an input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, and/or the step of Sib determining the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100.

One advantage with this embodiment is that with knowledge of the input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, and/or the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100, the signal generator 40 can be further controlled by the processing circuitry 101 for generating a stable desired predefined alternating current voltage output VAC-p-out with a desired sinus shaped signal frequency.

According to some embodiments the method further comprises the step of S2a controlling a signal generator unit 40 to output a sinus shaped signal to a switching amplifier unit 30 that has the same sinus shaped signal frequency as the input sinus shaped signal frequency f-in of the voltage conversion apparatus 100, or the step of S2b controlling the signal generator unit 40 to output a sinus shaped signal to the switching amplifier unit 30 that is maintained at a predefined frequency f-pre independent of the input sinus shaped signal frequency f-in.

One advantage with this embodiment is that the signal generator unit 40 can be controlled to output a predefined alternating current voltage output VAC-p-out from the voltage conversion apparatus 100 with the same sinus shaped signal frequency as the input sinus shaped signal frequency f-in of the voltage conversion apparatus 100 for e.g. an electrical control system configured for the specific sinus shaped signal frequency according to the alternating current voltage standard in that specific country.

Another advantage with this embodiment is that the signal generator unit 40 can also be controlled to output a predefined alternating current voltage output VAC-p-out from the voltage conversion apparatus 100 with a predefined sinus shaped signal frequency f-pre to e.g. maintain a correct operation of an electrical control system that is configured to operate according to a specific sinus shaped signal frequency independent on the alternating current voltage standard in the country where the voltage conversion apparatus is used.

According to some embodiments the method further comprises the step of S3 adjusting the signal generator unit 40 to output a sinus shaped signal to the switching amplifier unit 30 for generating a desired sinus shaped signal frequency output of the output of the switching amplifier unit 30.

One advantage with this embodiment is that with knowledge of the output sinus shaped signal frequency f-out of the voltage conversion apparatus 100, the signal generator unit 40 can be adjusted in order to maintain or generate a stable desired sinus shaped signal frequency output of the voltage conversion apparatus 100.

According to some embodiments the method further comprises the step of setting a predetermined output sinus shaped signal frequency of the voltage conversion apparatus 100 as indicative of a warning f-warn, and determining the output sinus shaped signal frequency f- out of the voltage conversion apparatus 100, and in accordance with a determination that the output sinus shaped signal frequency f-out corresponds to the predetermined output sinus shaped signal frequency indicative of a warning f-warn, outputting a notification signal indicative of a warning.

One advantage with this embodiment is that with knowledge of the output sinus shaped signal frequency is e.g. changing from a desired output sinus shaped signal frequency of the voltage conversion apparatus 100, this can be e.g. an indication of overheating or malfunction of the voltage conversion apparatus 100, and by outputting a notification signal indicative of a warning, the operation of the voltage conversion apparatus 100 can be supervised which eliminates further damage or faults due to an undesired output sinus shaped signal frequency.

The third aspect of this disclosure, as illustrated in Figure 3, shows a computer program product comprising a non-transitory computer readable medium 500, having thereon a computer program comprising program instructions, the computer program being loadable into a processing circuitry 101 and configured to cause execution of the method according to the second aspect when the computer program is run by the processing circuitry 101. The person skilled in the art realizes that the present disclosure is not limited to the preferred embodiments described above. The person skilled in the art further realizes that modifications and variations are possible within the scope of the appended claims. Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.