Double-frequency multi-output power supply capable of automatically identifying input voltage and frequency

Abstract

The utility model discloses a double-frequency multi-output power supply capable of automatically identifying input voltage and frequency, which comprises an input voltage automatic selection circuit, a control circuit and a double-frequency output circuit, the input voltage automatic selection circuit is connected with an alternating current input power supply, and the control circuit controls the double-frequency output circuit to output power supplies with different frequencies. According to the utility model, a single-phase input power supply is changed into a multi-voltage and dual-frequency output power supply, the voltage and frequency of the input single-phase power supply can be automatically identified, and the dual-frequency multi-voltage output power supply which can better meet the requirements of single-phase commercial power loads in various countries in the world is realized.

Description

Technical Field

[0001] This utility model relates to the field of power supply technology, specifically to a dual-frequency multi-output power supply that automatically identifies input voltage and frequency. Background Technology

[0002] With societal progress and technological advancements, economic and cultural exchanges between countries worldwide are constantly strengthening. In the face of natural disasters such as earthquakes and tsunamis, international aid is also continuously enhanced, with medical equipment undoubtedly being the most crucial resource. However, the mains voltage and frequency differ between countries, primarily falling into two categories: 220-240V / 50Hz and 100-127V / 60Hz. This leads to the incompatibility of electronic and medical equipment across different countries. Currently available power adapters can achieve some low-voltage compatibility and are mostly used for small electronic products. However, for some motor-type equipment, frequency compatibility is critical. Furthermore, safe and reliable operation, along with early warning systems to alert staff in case of malfunctions and ensure timely repairs, are the most important standards for medical power supplies. To address these issues, we have designed a universal dual-frequency multi-output power supply that automatically identifies the input voltage and frequency, utilizing a resonant circuit and a relay contactor system. Furthermore, a series-parallel design on the primary and secondary sides of the transformer provides multiple protections for the power system, ensuring safe and reliable operation. Summary of the Invention

[0003] This invention addresses the problem that existing power adapters cannot be used interchangeably with power supplies of different voltages and frequencies. It provides a dual-frequency multi-output power supply that automatically identifies the input voltage and frequency. This power supply can automatically identify the voltage and frequency of the input power supply and output multiple sets of voltages and different frequencies for customers to choose from.

[0004] The objective of this invention is achieved through the following technical solution: It includes an automatic input voltage selection circuit, a control circuit, and a dual-frequency output circuit. The automatic input voltage selection circuit is connected to an AC input power supply, and the control circuit controls the dual-frequency output circuit to output power supplies with different frequencies. This invention transforms a single-phase input power supply into a multi-voltage and dual-frequency output power supply, automatically identifying the input single-phase power supply voltage and frequency to better meet the needs of single-phase mains loads worldwide.

[0005] Preferably, the automatic input voltage selection circuit includes a relay KF1, a changeover switch SF1, and a transformer TA1. The common terminal of the changeover switch SF1 is connected to the L1 terminal of the AC input power supply. The first position of the changeover switch SF1 is connected to the coil of the relay KF1. The other end of the coil of the relay KF1 is connected to the N terminal of the AC input power supply. One normally closed contact of the relay KF1 is connected between the second position of the changeover switch SF1 and the primary winding of the transformer TA1. One normally open contact of the relay KF1 is connected in parallel between the second position of the changeover switch SF1 and the secondary winding of the transformer TA1.

[0006] The switch SF1 is used to control whether this circuit is in working state. The relay KF1 identifies the AC input power supply voltage. When the AC input power supply voltage meets the coil operating voltage requirement of relay KF1, relay KF1 operates, causing the AC input power supply to power transformer TA1 and making transformer TA1 work. If the AC input power supply voltage does not meet the coil operating voltage requirement of relay KF1, relay KF1 does not operate, and the AC input power supply bypasses transformer TA1 and is directly connected to the subsequent control circuit.

[0007] Preferably, a voltage indicator PG1 is connected in parallel between the primary winding of transformer TA1 and the N terminal of the AC input power supply. When the voltage of the AC input power supply does not meet the coil operating voltage requirement of relay KF1, the voltage indicator PG1 lights up, indicating that transformer TA1 is in operation at this time.

[0008] Preferably, a circuit breaker QA01 is also connected between the automatic input voltage selection circuit and the L1 terminal of the AC input power supply. The circuit breaker QA01 is used to control the AC input power supply to connect to the automatic input voltage selection circuit, and the circuit breaker QA01 has short-circuit and overload protection functions.

[0009] Preferably, the control circuit is connected to the secondary winding of transformer TA1, and a circuit breaker QA02 is provided between the secondary winding of transformer TA1 and the control circuit. Circuit breaker QA02 is used to control the output of the power supply on the secondary side of transformer TA1.

[0010] Preferably, the control circuit includes a power frequency identification circuit, which comprises an inductor RA1 and a capacitor CA1 connected in parallel. The inductor RA1 and capacitor CA1 are then connected in series with a resistor RA2 and a capacitor CA2. By selecting the parameters of the inductor RA1, capacitor CA1, resistor RA2, and capacitor CA2, the circuit is made to be in a parallel resonant state at a specific frequency, thereby making the current in the circuit almost zero, thus enabling the control circuit to achieve the function of AC power frequency identification.

[0011] Preferably, the control circuit includes a delay confirmation circuit, which includes a time-delay relay KF4. The use of the time-delay relay KF4 in the circuit ensures that the normally open contact of relay KF4 closes only after capacitor CA2 has finished charging, i.e., after the frequency identification process is complete, thus preventing circuit malfunctions caused by misidentification of the frequency.

[0012] Preferably, the dual-frequency output circuit includes two output path units, each with a different power supply frequency. One output path unit outputs a different voltage power supply at a specific frequency, while the other output path unit outputs a different voltage power supply at another specific frequency.

[0013] Preferably, the output path unit includes a transformer and a frequency converter module, with the frequency converter module connected to the primary winding side of the transformer. The frequency converter is used to control the power frequency of the input transformer's primary winding to remain constant, ensuring that the output frequency meets customer requirements.

[0014] Preferably, the primary winding of the transformer is composed of at least two sub-windings of the same specification connected in series, and the secondary winding of the transformer includes multiple independent sub-windings.

[0015] Preferably, the specifications of the individual windings are different. Different specifications of the individual windings result in different output power voltages.

[0016] Compared with the prior art, this utility model has the following advantages: This utility model transforms a single-phase input power supply into a multi-voltage and dual-frequency output power supply, which can automatically identify the input single-phase power supply voltage and frequency to better meet the single-phase mains load requirements of various countries around the world. In addition, it is designed with multiple protection functions such as preventing open circuit and relay contactor control system failure when the frequency converter is running under load to meet the needs of hospitals, foreign-related hotels, import product exchanges and other places. Attached Figure Description

[0017] Figure 1 This is a circuit structure diagram of the present invention;

[0018] Figure 2 This is a circuit system diagram of the present invention. Detailed Implementation

[0019] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0020] like Figure 1 , Figure 2As shown, a dual-frequency multi-output power supply that automatically identifies input voltage and frequency includes an automatic input voltage selection circuit, a control circuit, and a dual-frequency output circuit. The automatic input voltage selection circuit is connected to an AC input power supply, and the control circuit controls the dual-frequency output circuit to output power supplies with different frequencies.

[0021] In this embodiment, the rated voltages of the coils of relays KF1, KF2, KF3, and KF4, the rated voltages of the coils of AC contactors QA1, QA2, QA3, QA4, QA5, and QA6, and the rated voltages of indicator lights PG2, PG3, PG4, and PG5 are all 220V, while the rated voltage of indicator light PG1 is 110V.

[0022] The rated voltage of the primary winding of transformer TA1 is 110V, and the rated voltage of the secondary winding is 220V.

[0023] This embodiment uses two types of power supplies with input AC power voltages of 220V or 110V, which are common in different countries, as examples to illustrate the structure and operating principle of this technical solution:

[0024] The automatic input voltage selection circuit includes circuit breaker QA0. One end of circuit breaker QA0 is connected to the L terminal of the AC input power supply, and the other end is connected in sequence to the common terminal of circuit breaker QA01 and changeover switch SF1. The first position of changeover switch SF1 is connected to the coil of relay KF1. The other end of the coil of relay KF1 is connected to the N terminal of the AC input power supply. One normally closed contact of relay KF1 is connected between the second position of changeover switch SF1 and the primary winding of transformer TA1. One normally open contact of relay KF1 is connected in parallel between the second position of changeover switch SF1 and the secondary winding of transformer TA1. The second normally open contact of relay KF1 is connected in parallel between the coil of relay KF1 and circuit breaker QA01. A voltage indicator PG1 is connected in parallel between the primary winding of transformer TA1 and the N terminal of the AC input power supply.

[0025] The automatic input voltage selection circuit operates as follows:

[0026] When the input power supply voltage is 220V, manually closing the circuit breaker QA01 energizes the coil of relay KF1, closing the normally open contact KF1 and opening the normally closed contact KF1. The changeover switch SF1 switches from the initial first position to the second position, and the voltage indicator PG1 does not light up. At this time, the 220V input power supply voltage is directly output without passing through the transformer TA1.

[0027] When the input power supply voltage is 110V, manually closing circuit breaker QA01 results in relay KF1 coil experiencing a voltage lower than its operating voltage, thus its contacts do not operate. Switching changer SF1 from its initial first position to the second position illuminates the voltage indicator PG1, and the 110V input power supply is converted to 220V via the secondary winding of transformer TA1. Circuit breaker QA02 is connected to the secondary winding of transformer TA1 to control the output power from the secondary side of transformer TA1. Closing circuit breaker QA02 energizes the control circuit.

[0028] The control circuit includes AC contactors QA1, QA2, QA3, QA4, QA5, and QA6; indicator lights PG2, PG3, PG4, and PG5; and intermediate relays KF2, KF3, and KF4. One end of the third normally open contact of relay KF1 is connected in parallel with the first normally open auxiliary contact of AC contactor QA1, and the other end is connected to the other end of circuit breaker QA02. The other end of this parallel connection is connected to the first normally closed auxiliary contact of AC contactor QA2. The other end of the normally closed auxiliary contact of AC contactor QA2 is connected to one end of the coil of AC contactor QA1. The other end of the coil of AC contactor QA1 is connected to the N terminal of the input power supply. The coil of relay KF2 is connected in parallel across the two ends of the coil of AC contactor QA1. One end of the fourth normally open contact of relay KF1, the second normally open contact of KF2, and indicator light PG2 are connected in series with one end of the first normally open auxiliary contact of AC contactor QA1. The other end of this series connection is connected to the N terminal of the input power supply. The second normally closed contact of relays KF1 and KF2, the first normally closed auxiliary contact of AC contactor QA1, and the coil of AC contactor QA2 are connected in series. One end of these series connections is connected to one end of the first normally open auxiliary contact of AC contactor QA1, and the other end is connected to the N terminal of the input power supply. One end of the first normally open auxiliary contact of AC contactor QA2 is connected to one end of the fourth normally closed contact of relay KF1, and the other end is connected to the other end of the second normally closed contact of KF2. Inductor RA1 and capacitor CA1 are connected in parallel and then in series with resistor RA2 and capacitor CA2. Simultaneously, the circuit formed by the first normally closed auxiliary contact of AC contactors QA4 and QA6 connected in series with the coil of relay KF3 is connected in parallel across the two ends of the series circuit of resistor RA2 and capacitor CA2. The first normally open auxiliary contact of AC contactor QA3 is connected in series with the coil of AC contactor QA4. One end of the series connection is connected to one end of capacitor CA1, and the other end is connected to the N terminal of the input power supply. The first normally open auxiliary contact of AC contactor QA4 is connected in parallel across the two normally open auxiliary contacts of AC contactor QA3. Indicator light PG3 is connected in parallel across the two ends of the coil of AC contactor QA4. Similarly, the first normally open auxiliary contact of AC contactor QA5 is connected in series with the coil of AC contactor QA6. One end of the series connection is connected to one end of the first normally open auxiliary contact of AC contactor QA4, and the other end is connected to the N terminal of the input power supply. The first normally open auxiliary contact of AC contactor QA6 is connected in parallel across the two normally open auxiliary contacts of AC contactor QA5. Indicator light PG4 is connected in parallel across the two ends of the coil of AC contactor QA6. The second normally open auxiliary contact of AC contactors QA1, QA3, and QA4 is connected in series with indicator light PG5. One end of the circuit is connected to one end of the first normally open auxiliary contact of AC contactor QA6, and the other end is connected to the input power supply N terminal. The second normally open contact of AC contactor QA2 is connected in parallel across the two ends of the second normally open contact of AC contactor QA1. The circuit formed by the series connection of the second normally open contacts of AC contactors QA5 and QA6 is connected in parallel across the two ends of the circuit formed by the series connection of the second normally open contacts of AC contactors QA3 and QA4.One end of the coil of time-delay relay KF4 is connected to the second normally open auxiliary contact of AC contactor QA2, and the other end is connected to the N terminal of the power supply. One end of the normally open contact of time-delay relay KF4 is connected to one end of its coil, and the other end is connected to the normally open contact of relay KF3. One end of the circuit formed by connecting the normally open contact of relay KF3, the second normally open auxiliary contacts of AC contactors QA5 and QA6, and one end of the coil of AC contactor QA3 in series is connected to the other end of the normally open contact of time-delay relay KF4, and the other end is connected to the N terminal of the power supply. The second normally open auxiliary contact of AC contactor QA3 is connected in parallel across the two ends of the normally open contact of relay KF3. One end of the circuit formed by connecting the normally closed contact of relay KF3 in series with the second normally closed auxiliary contact of AC contactors QA3 and QA4 and one end of the coil of AC contactor QA5 is connected to the second normally open auxiliary contact of AC contactor QA3, and the other end of the circuit is connected to the input power supply N terminal. The second normally open auxiliary contact of AC contactor QA5 is connected in parallel across the normally closed contact of relay KF3.

[0029] In the above scheme, when the input power supply of the automatic input voltage selection circuit is 220V / 50HZ, the coil of AC contactor QA1 is energized, the coil of relay KF2 is energized, the coil of time relay KF4 is energized, the normally open contacts of AC contactor QA1, relay KF1, and relay KF2 are closed, and the indicator light PG2 is lit.

[0030] Inductor RA1, resistor RA2, capacitor CA2, and capacitor CA1 together form a power supply frequency identification circuit. When the current from the automatic input voltage selection circuit passes through this power supply frequency identification circuit:

[0031] When relay KF3 coil is energized, its normally open contact KF3 closes, and its normally closed contact KF3 opens. When the normally open contact of time relay KF4 closes, AC contactor QA3 coil is energized, frequency converter module TA5 operates, AC contactor QA3's normally open contact closes, AC contactor QA4 coil is energized, AC contactor QA4's normally open contact closes and self-locks, 50Hz indicator PG3 illuminates, and system normal operation indicator PG5 illuminates. Transformer TA2 outputs different voltages at a frequency of 50Hz on its secondary side, and transformer TA3 outputs different voltages at a frequency of 60Hz on its secondary side.

[0032] When the input power supply of the automatic input voltage selection circuit is 220V / 60HZ, the power frequency identification circuit composed of inductor RA1, resistor RA2, capacitor CA2, and capacitor CA1 makes the circuit approximately in a parallel resonant state, meaning the total current of the circuit is almost zero. The coil of relay KF3 experiences a very low voltage, far below its operating voltage. Therefore, relay KF3 and the normally closed contacts of AC contactors QA3 and QA4 do not operate, energizing the coil of AC contactor QA5. This causes the frequency converter module TA4 to operate, and the normally open contact of AC contactor QA5 to close and self-lock. Simultaneously, the coil of AC contactor QA6 is energized, and the normally open contact of AC contactor QA6 closes and self-locks. The 60Hz indicator PG4 illuminates, and the system normal operation indicator PG5 illuminates. The secondary side of transformer TA3 outputs different voltages at a frequency of 60Hz, and the secondary side of transformer TA2 outputs different voltages at a frequency of 50Hz.

[0033] When the input power supply of the automatic input voltage selection circuit is 110V / 50HZ, the 110V voltage indicator PG1 lights up, and the 110V input power supply is converted to 220V through the secondary side of transformer TA1. The coil of AC contactor QA2 is energized, and the normally open contact of AC contactor QA2 closes and self-locks. When the current of the automatic input voltage selection circuit passes through the power frequency identification circuit, the coil of relay KF3 is energized, the coil of time-delay relay KF4 is energized, the normally open contact of relay KF4 closes, the normally open contact of relay KF3 closes, the normally closed contact of relay KF3 opens, the coil of AC contactor QA3 is energized, the normally open contact of AC contactor QA3 closes, the frequency converter module TA5 operates, the coil of AC contactor QA4 is energized, the normally open contact of AC contactor QA4 closes and self-locks, the 50Hz indicator PG3 lights up, and the system normal operation indicator PG5 lights up. The secondary side of transformer TA2 outputs different voltages with a frequency of 50Hz, and the secondary side of transformer TA3 outputs different voltages with a frequency of 60Hz.

[0034] When the input power supply of the automatic input voltage selection circuit is 110V / 60HZ, the power frequency identification circuit composed of inductor RA1, resistor RA2, capacitor CA2, and capacitor CA1 makes the circuit approximately in a parallel resonant state, meaning the total current of the circuit is almost zero. The coil of relay KF3 experiences a very low voltage, far below its operating voltage, so the coil of relay KF3 is not energized. The coil of time-delay relay KF4 is energized, and the normally open contact of relay KF4 closes. Therefore, the normally closed contacts of relay KF3 and AC contactors QA3 and QA4 do not operate, energizing the coil of AC contactor QA5. The frequency converter module TA4 operates, and the normally open contact of AC contactor QA5 closes, self-locking with the normally open contact of relay KF3. Simultaneously, the coil of AC contactor QA6 is energized, the 60Hz indicator PG4 illuminates, the normally open contact of AC contactor QA5 closes and self-locks, and the system normal operation indicator PG5 illuminates. The secondary side of transformer TA2 outputs different voltages with a frequency of 50Hz, and the secondary side of transformer TA3 outputs different voltages with a frequency of 60Hz.

[0035] The dual-frequency output circuit in this embodiment includes two output path units, namely output path unit I and output path unit II. The transformer in output path unit I is TA2, and the transformer in output path unit II is TA3. The primary windings of transformers TA2 and TA3 are both two 110V windings connected in series. The secondary windings of transformers TA2 and TA3 consist of 9 independent windings. By selecting the winding parameters, the output voltage of each winding is different.

[0036] One end of each of the nine windings on the secondary side of transformer TA2 is connected to one end of circuit breakers QA11, QA12, QA13, QA14, QA15, QA16, QA17, QA18, and QA19, respectively. The other ends of QA11, QA12, QA13, QA14, QA15, QA16, QA17, QA18, and QA19 are the phase terminals L240, L230, L220, L200, L127, L120, L115, L110, and L100, respectively, which output 50Hz voltages of 240V, 230V, 220V, 200V, 127V, 120V, 115V, 110V, and 100V. The other ends of the nine windings on the secondary side of transformer TA2 are connected to the N terminal of the input power supply. One end of the first normally open main contact of AC contactor QA3 is connected to the other end of circuit breaker QA0. One end of the parallel connection of the first normally open main contacts of AC contactors QA1 and QA2 is connected to the other end of the first normally open main contact of AC contactor QA3. The other end of the second 110V winding on the primary side of transformer TA2 is also connected to the N terminal of the input power supply. One end of the first 110V winding of the primary winding of transformer TA2 is connected to the first normally open main contact of QA1, and the other end is connected to the first normally open main contact of QA2. The third normally open main contact of AC contactor QA5 is connected in parallel with the normally open main contact of AC contactor QA6. One end of this connection is connected to one end of the first 110V winding of the primary winding of transformer TA2, and the other end is connected to the power output phase line terminal of frequency converter TA4. The N terminal of TA4 is connected to the N terminal of the input power supply. In addition, one end of the second normally open main contact of AC contactor QA5 is connected to the phase line input terminal of frequency converter TA4, and the other end is connected to one end of the second normally open main contact of QA1. The input N terminal of frequency converter TA4 is connected to the N terminal of the input power supply, and the input XE terminal of frequency converter TA4 is connected to the protective neutral terminal XE of the input power supply.

[0037] One end of each of the nine windings on the secondary side of transformer TA3 is connected to one end of circuit breakers QA21, QA22, QA23, QA24, QA25, QA26, QA217, QA28, and QA29, respectively. The other ends of QA21, QA22, QA23, QA24, QA25, QA26, QA217, QA28, and QA29 are the phase terminals V240, V230, V220, V200, V127, V120, V115, V110, and V100, respectively, which output 240V, 230V, 220V, 200V, 127V, 120V, 115V, 110V, and 100V voltages at 60Hz. The other ends of the nine windings on the secondary side of transformer TA3 are connected to the N terminal of the input power supply. One end of the first normally open main contact of AC contactor QA5 is connected to the other end of circuit breaker QA0. One end of the second normally open main contact of AC contactors QA1 and QA2 is connected to the other end of the first normally open main contact of AC contactor QA5. The other end of the second 110V winding on the primary side of transformer TA3 is also connected to the neutral line N terminal of the input power supply. The third normally open main contact of AC contactor QA3 is connected in parallel with the normally open main contact of AC contactor QA4. One end is connected to one end of the first 110V winding of the primary winding of transformer TA3, and the other end is connected to the power output phase line terminal of frequency converter TA5. The N terminal of TA5 is connected to the N terminal of the input power supply. In addition, the phase line input terminal of the frequency converter TA5 is connected to the other end of the second normally open main contact of the AC contactor QA3, one end of the second normally open main contact of QA3 is connected to the other end of the first normally open main contact of QA1, the N terminal of the frequency converter TA5 is connected to the N terminal of the input power supply, and the XE terminal of the frequency converter TA5 is connected to the XE terminal of the input power supply.

[0038] This utility model transforms a single-phase input power supply into a multi-voltage and dual-frequency output power supply. It can automatically identify the input single-phase power supply voltage and frequency to better meet the single-phase mains load requirements of various countries. Furthermore, it is designed with multiple protection functions, such as preventing open circuits and relay contactor control system failures during the operation of the frequency converter under load, to meet the needs of hospitals, foreign-related hotels, import product exchanges, and other places.

Claims

1. A dual-frequency multi-output power supply that automatically identifies input voltage and frequency, characterized in that: It includes an automatic input voltage selection circuit, a control circuit, and a dual-frequency output circuit. The automatic input voltage selection circuit is connected to the AC input power supply, and the control circuit controls the dual-frequency output circuit to output power supplies with different frequencies. The automatic input voltage selection circuit includes a relay KF1, a changeover switch SF1, and a transformer TA1. The common terminal of the changeover switch SF1 is connected to the L1 terminal of the AC input power supply. The first position of the changeover switch SF1 is connected to the coil of the relay KF1. The other end of the coil of the relay KF1 is connected to the N terminal of the AC input power supply. One normally closed contact of the relay KF1 is connected between the second position of the changeover switch SF1 and the primary winding of the transformer TA1. One normally open contact of the relay KF1 is connected in parallel between the second position of the changeover switch SF1 and the secondary winding of the transformer TA1.

2. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 1, characterized in that: A voltage indicator light PG1 is connected in parallel between the primary winding of the transformer TA1 and the N terminal of the AC input power supply.

3. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 1, characterized in that: A circuit breaker QA01 is also connected between the automatic input voltage selection circuit and the L1 terminal of the AC input power supply.

4. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 1, characterized in that: The control circuit is connected to the secondary winding of transformer TA1, and a circuit breaker QA02 is provided between the secondary winding of transformer TA1 and the control circuit.

5. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 4, characterized in that: The control circuit includes a power frequency identification circuit, which includes an inductor RA1 and a capacitor CA1 connected in parallel. The inductor RA1 and the capacitor CA1 are connected in parallel and then connected in series with a resistor RA2 and a capacitor CA2.

6. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 4, characterized in that: The control circuit includes a delay confirmation circuit, which includes a delay relay KF4.

7. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 1, characterized in that: The dual-frequency output circuit includes two output path units, each with a different power supply frequency.

8. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 7, characterized in that: The output path unit includes a transformer and a frequency converter module, with the frequency converter module connected to the primary winding side of the transformer.

9. The dual-frequency multi-output power supply with automatic input voltage and frequency identification according to claim 8, characterized in that: The primary winding of the transformer is composed of at least two sub-windings of the same specification connected in series, and the secondary winding of the transformer includes multiple independent sub-windings, each with different specifications.

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