Voltage conversion unit, setting method, program, and non-transitory recording medium

Abstract

This voltage conversion unit comprises a voltage control unit, a voltage comparison unit, a voltage dividing circuit, and a correction circuit. The voltage comparison unit controls the magnitude of the output voltage (Vout) of the voltage control unit in accordance with the difference between a reference voltage (Vref) and a comparison voltage (Vc). The voltage dividing circuit outputs, to the voltage comparison unit, a comparison voltage (Vc) which is the voltage at a connection point between a second end of a first resistor and a first end of a second resistor. The correction circuit generates a correction voltage (Vh) on the basis of the comparison result between the output voltage (Vout) of the voltage control unit and the initial voltage stored in a storage unit, and outputs the correction voltage (Vh) to the connection point.

Description

Voltage conversion unit, setting method, program, and non-transitory recording medium

[0001] The present disclosure generally relates to a voltage conversion unit, a setting method, and a program. More particularly, the present disclosure relates to a voltage conversion unit that converts DC voltage, a setting method for the voltage conversion unit, a program, and a non-transitory recording medium for recording the program.

[0002] The power supply device described in Patent Document 1 includes a main power supply circuit and a digital control IC. The digital control IC forms a feedback circuit including an ADC (analog-to-digital converter), a comparator, a calculation unit, and a DPWM. The ADC quantizes analog output voltage information of the main power supply circuit into digital output voltage information. The comparator outputs the difference between target voltage information and the digital output voltage information as error value information. The calculation unit outputs control amount information to a DPWM (digitally adjusted pulse width modulation) based on the error value information. The DPWM generates and outputs a power supply control signal in accordance with the control amount information. The output voltage of the main power supply circuit is adjusted by the power supply control signal.

[0003] JP 2010-279134 A

[0004] A voltage conversion unit according to one aspect of the present disclosure includes a voltage control unit, a voltage comparison unit, a voltage divider circuit, and a correction circuit. The voltage control unit has an input terminal and an output terminal, and generates a DC output voltage from the output terminal based on a DC input voltage input to the input terminal. The voltage comparison unit controls the magnitude of the output voltage of the voltage control unit according to a difference between a reference voltage and a comparison voltage. The voltage divider circuit is electrically connected to the output terminal of the voltage control unit. The correction circuit is electrically connected to the output terminal of the voltage control unit. The voltage divider circuit includes a first resistor and a second resistor. A first end of the first resistor is electrically connected to the output terminal of the voltage control unit. A second end of the first resistor is electrically connected to the first end of the second resistor. A second end of the second resistor is electrically connected to ground. The voltage divider circuit outputs the comparison voltage, which is the voltage at the connection point between the second end of the first resistor and the first end of the second resistor, to the voltage comparison unit. The correction circuit generates a correction voltage based on a comparison result between the output voltage of the voltage control unit and an initial voltage stored in a storage unit, and outputs the correction voltage to the connection point.

[0005] A setting method according to one aspect of the present disclosure is a setting method for the voltage conversion unit, and includes a first step and a second step. In the first step, a control system applies a desired voltage to the output terminal of the voltage control unit when operation of the voltage control unit is stopped. In the second step, when the desired voltage is applied to the output terminal of the voltage control unit in the first step, the control system stores a measured value of the desired voltage input to the correction circuit as the initial voltage in the memory unit.

[0006] A program according to one aspect of the present disclosure is a program readable by a computer system, causing one or more processors of the computer system to execute the setting method.

[0007] The present disclosure can reduce errors in output voltage caused by manufacturing errors of components of a voltage conversion unit.

[0008] Fig. 1 is a block diagram of a voltage conversion unit according to an embodiment, Fig. 2 is a block diagram showing a state when an initial voltage is set in the voltage conversion unit according to an embodiment, and Fig. 3 is a flowchart showing a method for setting an initial voltage of the voltage conversion unit according to an embodiment.

[0009] In the power supply device (voltage conversion unit) described in Patent Document 1, manufacturing errors in the components of the power supply device may cause errors in the error value information output from the comparator, for example, which may result in errors in the output voltage of the main power supply circuit.

[0010] The present disclosure can reduce errors in output voltage caused by manufacturing errors of components of a voltage conversion unit.

[0011] (Embodiments) Hereinafter, a voltage conversion unit 1, a setting method, and a program according to an embodiment will be described with reference to the drawings. However, the following embodiment is merely one of various embodiments of the present disclosure. The following embodiment can be modified in various ways depending on the design, etc., as long as the effects of the present disclosure can be obtained.

[0012] The term "terminal" as used herein may be any component that can be electrically connected to another component. The term "terminal" may be a component such as a connector for connecting an electric wire, or may be a part of a conductor such as a wire, a printed wiring, or a metal wiring in a semiconductor.

[0013] (Overview) Fig. 1 shows the configuration of a voltage conversion unit 1 according to this embodiment. The voltage conversion unit 1 is a DC / DC converter that converts a DC voltage. That is, the voltage conversion unit 1 boosts or lowers the DC voltage and outputs it to a power supply target (load). The power supply target is, for example, a home appliance or a power storage system. The voltage conversion unit 1 is used, for example, as part of a backup power supply.

[0014] The voltage conversion unit 1 includes a voltage control unit 2, a voltage comparison unit 3, a voltage divider circuit 4, and a correction circuit 5. The voltage control unit 2 has an input terminal 21 and an output terminal 22, and generates a DC output voltage Vout from the output terminal 22 based on a DC input voltage Vin input to the input terminal 21. The voltage comparison unit 3 controls the magnitude of the output voltage Vout of the voltage control unit 2 in accordance with the difference between a reference voltage Vref and a comparison voltage Vc. The voltage divider circuit 4 is electrically connected to the output terminal 22 of the voltage control unit 2. The correction circuit 5 is electrically connected to the output terminal 22 of the voltage control unit 2. The voltage divider circuit 4 includes a first resistor 41 and a second resistor 42. A first end of the first resistor 41 is electrically connected to the output terminal 22 of the voltage control unit 2. A second end of the first resistor 41 is electrically connected to a first end of the second resistor 42. A second end of the second resistor 42 is electrically connected to ground. The voltage divider circuit 4 outputs a comparison voltage Vc, which is the voltage at a connection point 43 between the second end of the first resistor 41 and the first end of the second resistor 42, to the voltage comparator 3. The correction circuit 5 generates a correction voltage Vh based on a comparison result between the output voltage Vout of the voltage controller 2 and the initial voltage stored in the memory unit 65, and outputs the correction voltage Vh to the connection point 43.

[0015] That is, the voltage divider circuit 4 outputs a comparison voltage Vc, which is a voltage corresponding to the divided voltage of the output voltage Vout, to the voltage comparator 3. The voltage comparator 3 controls the magnitude of the output voltage Vout of the voltage controller 2 in accordance with the difference between the reference voltage Vref and the comparison voltage Vc. By feedback-controlling the output voltage Vout in this way, the magnitude of the output voltage Vout becomes a desired magnitude.

[0016] The correction circuit 5 then outputs the correction voltage Vh to the connection point 43, thereby correcting the comparison voltage Vc. This makes it possible to reduce errors in the output voltage Vout due to manufacturing errors of the components of the voltage conversion unit 1.

[0017] (Details) (1) Overall Configuration As described above, the voltage conversion unit 1 includes a voltage control unit 2, a voltage comparison unit 3, a voltage divider circuit 4, and a correction circuit 5. In order to set an initial voltage when the operation of the voltage control unit 2 is stopped, the voltage conversion unit 1 is electrically connected to a power supply 9 as shown in Fig. 2 and is further controlled by a control system 8. Note that, since the operation of the voltage control unit 2 is stopped in Fig. 2, the voltage control unit 2 and the voltage comparison unit 3 that controls the voltage control unit 2 are not shown.

[0018] (2) Voltage Control Unit The voltage control unit 2 has an input terminal 21 , an output terminal 22 , a control terminal 23 , a voltage conversion circuit 24 , and a control circuit 25 .

[0019] The voltage conversion circuit 24 is a switching power supply including a switching element such as a field effect transistor (FET). The voltage conversion circuit 24 boosts or lowers the input voltage Vin input to the input terminal 21 by turning on or off the switching element, and outputs the boosted voltage as an output voltage Vout from the output terminal 22.

[0020] The control circuit 25 controls the on / off of the switching elements of the voltage conversion circuit 24 based on the control signal S1 input to the control terminal 23. The control circuit 25 is configured by, for example, an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0021] (3) Voltage Comparator The voltage comparator 3 is a comparator including an operational amplifier 30. The operational amplifier 30 has a first input terminal 31, a second input terminal 32, and an output terminal 33.

[0022] A reference voltage Vref is input to the first input terminal 31. The reference voltage Vref is a constant DC voltage and is generated by an external power supply.

[0023] A comparison voltage Vc is input to the second input terminal 32. The comparison voltage Vc is a DC voltage output from the connection point 43 of the voltage divider circuit 4.

[0024] The voltage comparator 3 outputs a binary signal as the control signal S1 from the output terminal 33. More specifically, when the reference voltage Vref, which is the voltage input to the first input terminal 31, is greater than the comparison voltage Vc, which is the voltage input to the second input terminal 32, the magnitude of the control signal S1 becomes a first level (high level). On the other hand, when the reference voltage Vref, which is the voltage input to the first input terminal 31, is smaller than the comparison voltage Vc, which is the voltage input to the second input terminal 32, the magnitude of the control signal S1 becomes a second level (low level).

[0025] When the control signal S1 input to the control terminal 23 is at the first level, the control circuit 25 increases the output voltage Vout by lengthening the on time of the switching element of the voltage conversion circuit 24. In other words, when the reference voltage Vref is greater than the comparison voltage Vc, the control circuit 25 increases the output voltage Vout.

[0026] When the control signal S1 input to the control terminal 23 is at the second level, the control circuit 25 reduces the output voltage Vout by shortening the on time of the switching element of the voltage conversion circuit 24. In other words, when the reference voltage Vref is smaller than the comparison voltage Vc, the control circuit 25 reduces the output voltage Vout.

[0027] (4) Voltage Divider Circuit The configuration of the voltage divider circuit 4 is as described above.

[0028] (5) Correction Circuit The correction circuit 5 has a correction information calculation unit 6 and a correction voltage generation unit 7. The correction information calculation unit 6 generates correction information based on a comparison result between the output voltage Vout of the voltage control unit 2 and the initial voltage stored in the memory unit 65. The correction voltage generation unit 7 is electrically connected to the connection point 43. The correction voltage generation unit 7 generates a correction voltage Vh based on the correction information and outputs the correction voltage Vh to the connection point 43. This will be described in more detail below.

[0029] The correction information calculation unit 6 includes an input terminal 61 , an output terminal 62 , an ADC (analog-digital converter) 63 , a processing unit 64 , and a storage unit 65 .

[0030] The ADC 63 converts the analog output voltage Vout input to the input terminal 61 into a digital value.

[0031] As an example, the processing unit 64 is a microcontroller, although the processing unit 64 may also be composed of multiple discrete components.

[0032] The processing unit 64 generates correction information based on a comparison result between the output voltage Vout converted to a digital value by the ADC 63 and the initial voltage stored in the storage unit 65. Specifically, the processing unit 64 (correction information calculation unit 6) outputs the correction information as a PWM (pulse width modulation) signal S2. The PWM signal S2 is output from the output terminal 62. If the output voltage Vout (digital value) of the voltage control unit 2 is greater than the initial voltage stored in the storage unit 65, the processing unit 64 (correction information calculation unit 6) increases the duty of the PWM signal S2. If the output voltage Vout (digital value) of the voltage control unit 2 is smaller than the initial voltage stored in the storage unit 65, the processing unit 64 (correction information calculation unit 6) decreases the duty of the PWM signal S2.

[0033] As an example, the storage unit 65 is a non-volatile storage device configured by a hard disk drive (HDD), a solid state drive (SSD), etc. The initial voltage is stored in the storage unit 65 by a procedure described below. The processing unit 64 reads the initial voltage from the storage unit 65.

[0034] The correction voltage generating unit 7 includes an input terminal 71, an output terminal 72, a fourth resistor 73, a fifth resistor 74, a smoothing circuit 75, an operational amplifier 76, and a third resistor 77. The operational amplifier 76 has a first input terminal 761 (non-inverting input terminal), a second input terminal 762 (inverting input terminal), and an output terminal 763.

[0035] A first end of the fourth resistor 73 is electrically connected to the input terminal 71. A second end of the fourth resistor 73 is electrically connected to a first input terminal 761 of the operational amplifier 76.

[0036] A first end of the fifth resistor 74 is electrically connected to a connection point 78 between the second end of the fourth resistor 73 and a first input terminal 761 of the operational amplifier 76. A second end of the fifth resistor 74 is electrically connected to ground.

[0037] The smoothing circuit 75 includes a capacitor 750. A first end of the capacitor 750 is electrically connected to the connection point 78. A second end of the capacitor 750 is electrically connected to ground.

[0038] A first end of the third resistor 77 is electrically connected to the output terminal 763 of the operational amplifier 76. A second end of the third resistor 77 is electrically connected to the output terminal 72.

[0039] A connection point 79 between the first end of the third resistor 77 and the output terminal 763 of the operational amplifier 76 is electrically connected to the second input terminal 762 of the operational amplifier 76. In other words, the output terminal 763 of the operational amplifier 76 is electrically connected to the second input terminal 762, and the operational amplifier 76 is in a negative feedback state.

[0040] The PWM signal S2 output from the output terminal 62 of the correction information calculation unit 6 is input to the input terminal 71 of the correction voltage generation unit 7. The smoothing circuit 75 smoothes the PWM signal S2 input to the input terminal 71. The signal smoothed by the smoothing circuit 75 (hereinafter referred to as the smoothed signal) is input to a first input terminal 761 of the operational amplifier 76.

[0041] The operational amplifier 76 amplifies the smoothed signal output from the smoothing circuit 75 to generate a correction voltage Vh (DC voltage signal), and outputs the correction voltage Vh to a connection point 43 between the second end of the first resistor 41 and the first end of the second resistor 42 of the voltage-dividing circuit 4. More specifically, the correction voltage Vh is output to the connection point 43 via a third resistor 77. Here, the provision of the third resistor 77 between the connection point 43 and the operational amplifier 76 facilitates fine adjustment of the voltage at the connection point 43 (comparison voltage Vc).

[0042] Since the output signal of the correction information calculation unit 6 is the PWM signal S2, the magnitude of the correction voltage Vh can be finely adjusted according to the variable amount of the duty of the PWM signal S2. For example, if the amplitude of the PWM signal S2 is A, the duty is D, the resistance value of the fourth resistor 73 is R4, and the resistance value of the fifth resistor 74 is R5, the correction voltage Vh can be expressed by the following equation.

[0043]

[0044] For example, when A=5 [V], R3=R4, and the duty can take a value of 12 bits, the minimum change amount of the correction voltage Vh is 5×(½ １２ ) / 2=0.6 [mV].

[0045] (6) Output Voltage As described above, the comparison voltage Vc input to the voltage comparison unit 3 is corrected by the correction circuit 5 outputting the correction voltage Vh. This corrects the output voltage Vout output from the voltage control unit 2. The output voltage Vout is expressed by the following equation: where R1, R2, and R3 are the resistance values ​​of the first resistor 41, the second resistor 42, and the third resistor 77, respectively.

[0046]

[0047] As described above, the correction circuit 5 can finely adjust the magnitude of the correction voltage Vh, thereby enabling the correction circuit 5 to finely adjust the magnitude of the output voltage Vout output from the voltage control unit 2.

[0048] (7) Setting of Initial Voltage The setting method of this embodiment is a setting method of the voltage conversion unit 1. More specifically, the setting method is a method of storing the initial voltage of the voltage conversion unit 1 in the storage unit 65.

[0049] The setting method includes a first step and a second step. In the first step, when the operation of the voltage control unit 2 is stopped, the control system 8 (see FIG. 2 ) applies the desired voltage Vd to the output terminal 22 of the voltage control unit 2. The desired voltage Vd is a DC voltage. In the second step, when the desired voltage Vd is applied to the output terminal 22 of the voltage control unit 2 in the first step, the control system 8 stores the measured value of the desired voltage Vd input to the correction circuit 5 in the memory unit 65 as an initial voltage.

[0050] The setting method can be realized as a program. The program of this embodiment is a program readable by a computer system and causes one or more processors of the computer system to execute the setting method. The program may be recorded on a non-transitory recording medium readable by the computer system.

[0051] The setting method will be described in more detail below with reference to Figures 2 and 3. Note that the flowchart shown in Figure 3 merely shows one example of the setting method according to the present disclosure, and the order of the processes may be changed as appropriate, and processes may be added or omitted as appropriate.

[0052] First, the user stops the operation of the voltage control unit 2 (step ST1). Next, the user electrically connects the power supply 9 to the output terminal 22 of the voltage control unit 2. The user also connects the control system 8 to the power supply 9 and the correction information calculation unit 6 so that they can communicate with each other. In the present disclosure, "being able to communicate" means that signals can be sent and received directly or indirectly via a network, a repeater, or the like, by an appropriate communication method such as wired communication or wireless communication.

[0053] The control system 8 includes a computer system having one or more processors and a memory. At least some of the functions of the control system 8 are realized by the processor of the computer system executing a program recorded in the memory of the computer system. The program may be recorded in the memory, or may be provided via a telecommunications line such as the Internet, or may be provided by being recorded on a non-transitory recording medium (such as a memory card) that can be read by the computer system.

[0054] The control system 8 executes the first and second steps described above.

[0055] That is, after the operation of the voltage control unit 2 stops in step ST1, the control system 8 controls the power supply 9 to apply the desired voltage Vd to the output terminal 22 from the power supply 9 (first step ST2).

[0056] Furthermore, the control system 8 controls the correction information calculation unit 6. As a result, the correction information calculation unit 6 measures the voltage input to the input terminal 61, i.e., the desired voltage Vd (step ST3). The correction information calculation unit 6 stores the measured value of the desired voltage Vd in the storage unit 65 as an initial voltage (step ST4). Specifically, the ADC 63 of the correction information calculation unit 6 converts the analog desired voltage Vd into a digital value, and this digital value is stored in the storage unit 65 as the measured value of the desired voltage Vd (initial voltage).

[0057] Steps ST3 and ST4 correspond to the second step described above.

[0058] The setting method is completed by the above processing.

[0059] The desired voltage Vd applied to the output terminal 22 in the first step ST2 is a voltage of a magnitude that the user considers desirable as the magnitude of the output voltage Vout output from the output terminal 22 when the voltage control unit 2 is operated.

[0060] A measurement error may occur when the desired voltage Vd is applied to the output terminal 22 in the first step ST2 and the desired voltage Vd is measured by the correction information calculation unit 6. Factors that may cause the measurement error include, for example, an error in the electrical resistance values ​​of the first resistor 41 and the second resistor 42 of the voltage divider circuit 4, a reading error when the ADC 63 reads the analog output voltage Vout, and a conversion error when the ADC 63 converts the analog output voltage Vout into a digital value. Furthermore, if another circuit (such as a voltage divider circuit) is present between the output terminal 22 and the input terminal 61 of the correction information calculation unit 6, an error in the electrical characteristics of this circuit may also cause a measurement error.

[0061] Due to measurement errors, the initial voltage may differ in magnitude from the desired voltage Vd actually applied to the output terminal 22 .

[0062] (8) Description of Operation Assume that, using the above setting method, a voltage of 10 [V] is applied to the output terminal 22 as the desired voltage Vd. The correction information calculation unit 6 does not measure a voltage of 10 [V], but rather measures a voltage of, for example, 9.5 [V] due to a measurement error, and therefore the value of 9.5 [V] is stored in the storage unit 65 as the initial voltage.

[0063] Thereafter, when the voltage control unit 2 is operating, if the voltage conversion unit 1 operates so that the value (hereinafter referred to as the output voltage measurement value) of the output voltage Vout of the voltage control unit 2 measured by the correction information calculation unit 6 is 9.5 [V], the output voltage Vout from the output terminal 22 is considered to be 10 [V].

[0064] Therefore, when the voltage control unit 2 is operating, the correction information calculation unit 6 generates correction information (PWM signal S2) so that the measured output voltage value matches the initial voltage (9.5 V). Specifically, if the measured output voltage value is greater than the initial voltage, the correction information calculation unit 6 increases the duty of the PWM signal S2. On the other hand, if the measured output voltage value is smaller than the initial voltage, the correction information calculation unit 6 decreases the duty of the PWM signal S2. As a result, the voltage control unit 2 operates so that the output voltage Vout (actual voltage value) from the output terminal 22 becomes 10 V. In other words, the voltage control unit 2 can output the desired voltage Vd.

[0065] Until the output voltage Vout of the voltage control unit 2 is input to the correction information calculation unit 6, the correction information calculation unit 6 only needs to generate the PWM signal S2 whose duty cycle matches the predetermined initial value.

[0066] (Modifications of the embodiment) Modifications of the embodiment are listed below. The following modifications may be implemented in appropriate combination. Hereinafter, the configuration of the above-described embodiment will be referred to as a basic example.

[0067] It is not essential that the storage unit 65 is a component of the correction information calculation unit 6. In other words, the storage unit 65 may be provided outside the correction information calculation unit 6.

[0068] The control system 8 may be configured as a voltage conversion unit 1 .

[0069] In the basic example, the control circuit 25 increases the output voltage Vout when the reference voltage Vref is greater than the comparison voltage Vc. Alternatively, the control circuit 25 may increase the output voltage Vout when the reference voltage Vref is greater than the comparison voltage Vc and the absolute value of the difference between the reference voltage Vref and the comparison voltage Vc is equal to or greater than a first threshold value.

[0070] In the basic example, the control circuit 25 reduces the output voltage Vout when the reference voltage Vref is lower than the comparison voltage Vc. Alternatively, the control circuit 25 may reduce the output voltage Vout when the reference voltage Vref is lower than the comparison voltage Vc and the absolute value of the difference between the reference voltage Vref and the comparison voltage Vc is equal to or greater than a second threshold. The second threshold may be equal to the first threshold.

[0071] The execution entity of the voltage conversion unit 1 or the setting method of the present disclosure includes a computer system. The computer system is primarily composed of a processor and memory as hardware. At least a portion of the functions of the execution entity of the voltage conversion unit 1 or the setting method of the present disclosure are realized by the processor executing a program recorded in the memory of the computer system. The program may be pre-recorded in the memory of the computer system, provided via a telecommunications line, or provided by being recorded on a non-transitory recording medium readable by the computer system, such as a memory card, an optical disk, or a hard disk drive. The processor of the computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI). The integrated circuits, such as ICs and LSIs, are referred to by different names depending on the degree of integration, and include integrated circuits called system LSIs, very large-scale integration (VLSI), or ultra-large-scale integration (ULSI). Furthermore, a field-programmable gate array (FPGA), which is programmed after the LSI is manufactured, or a logic device capable of reconfiguring the connections within the LSI or the circuit partitions within the LSI, can also be employed as a processor. Multiple electronic circuits may be integrated into a single chip or distributed across multiple chips. Multiple chips may be integrated into a single device or distributed across multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits, including a semiconductor integrated circuit or a large-scale integrated circuit.

[0072] In addition, in the embodiment, multiple components that are integrated into one housing may be distributed across multiple housings. For example, the housing for the voltage conversion circuit 24 may be provided separately from the housing for the control circuit 25.

[0073] Conversely, in the embodiment, multiple functions distributed across multiple housings may be integrated into one housing. For example, the correction information calculation unit 6 and the correction voltage generation unit 7 may be integrated into one housing. Furthermore, one microcontroller may have the functions of the correction information calculation unit 6 and the correction voltage generation unit 7.

[0074] (Summary) The above-described embodiments and the like disclose the following aspects.

[0075] A voltage conversion unit (1) according to a first aspect includes a voltage control unit (2), a voltage comparison unit (3), a voltage divider circuit (4), and a correction circuit (5). The voltage control unit (2) has an input terminal (21) and an output terminal (22), and generates a DC output voltage (Vout) output from the output terminal (22) based on a DC input voltage (Vin) input to the input terminal (21). The voltage comparison unit (3) controls the magnitude of the output voltage (Vout) of the voltage control unit (2) in accordance with the difference between a reference voltage (Vref) and a comparison voltage (Vc). The voltage divider circuit (4) is electrically connected to the output terminal (22) of the voltage control unit (2). The correction circuit (5) is electrically connected to the output terminal (22) of the voltage control unit (2). The voltage divider circuit (4) includes a first resistor (41) and a second resistor (42). A first end of the first resistor (41) is electrically connected to an output terminal (22) of the voltage control unit (2). A second end of the first resistor (41) is electrically connected to a first end of the second resistor (42). A second end of the second resistor (42) is electrically connected to ground. The voltage divider circuit (4) outputs a comparison voltage (Vc), which is the voltage at a connection point (43) between the second end of the first resistor (41) and the first end of the second resistor (42), to the voltage comparator (3). The correction circuit (5) generates a correction voltage (Vh) based on a comparison result between the output voltage (Vout) of the voltage control unit (2) and an initial voltage stored in the memory unit (65), and outputs the correction voltage (Vh) to the connection point (43).

[0076] According to the above configuration, it is possible to reduce errors in the output voltage (Vout) caused by product errors of the components of the voltage conversion unit (1).

[0077] In the voltage conversion unit (1) according to the second aspect, the correction circuit (5) in the first aspect includes a correction information calculation unit (6) and a correction voltage generation unit (7). The correction information calculation unit (6) generates correction information based on a comparison result between the output voltage (Vout) of the voltage control unit (2) and an initial voltage stored in a memory unit (65). The correction voltage generation unit (7) is electrically connected to a connection point (43). The correction voltage generation unit (7) generates a correction voltage (Vh) based on the correction information and outputs the correction voltage (Vh) to the connection point (43).

[0078] According to the above configuration, it is possible to reduce errors in the output voltage (Vout) caused by product errors of the components of the voltage conversion unit (1).

[0079] In the voltage conversion unit (1) according to the third aspect, in the second aspect, the correction information calculation unit (6) outputs the correction information as a PWM signal (S2). The correction voltage generation unit (7) includes a smoothing circuit (75) and an operational amplifier (76). The smoothing circuit (75) smoothes the PWM signal (S2). The operational amplifier (76) amplifies the signal output from the smoothing circuit (75) to generate a correction voltage (Vh), and outputs the correction voltage (Vh) to the connection point (43).

[0080] According to the above configuration, the correction information calculation unit (6) can be configured with a digital circuit such as a microcomputer.

[0081] In addition, in the voltage conversion unit (1) according to the fourth aspect, in the third aspect, the correction information calculation unit (6) increases the duty of the PWM signal (S2) when the output voltage (Vout) of the voltage control unit (2) is greater than the initial voltage stored in the memory unit (65).

[0082] According to the above configuration, when the output voltage (Vout) is excessively high, the output voltage (Vout) can be corrected.

[0083] In addition, in the voltage conversion unit (1) according to the fifth aspect, in the third or fourth aspect, the correction information calculation unit (6) reduces the duty of the PWM signal (S2) when the output voltage (Vout) of the voltage control unit (2) is smaller than the initial voltage stored in the memory unit (65).

[0084] According to the above configuration, when the output voltage (Vout) is too low, the output voltage (Vout) can be corrected.

[0085] The configurations other than the first aspect are not essential for the voltage conversion unit (1) and can be omitted as appropriate.

[0086] A setting method according to a sixth aspect is a setting method for a voltage conversion unit (1) according to any one of the first to fifth aspects, and includes a first step and a second step. In the first step, when the operation of the voltage control unit (2) is stopped, the control system (8) applies a desired voltage (Vd) to the output terminal (22) of the voltage control unit (2). In the second step, when the desired voltage (Vd) is applied to the output terminal (22) of the voltage control unit (2) in the first step, the control system (8) stores a measured value of the desired voltage (Vd) input to the correction circuit (5) in the memory unit (65) as an initial voltage.

[0087] According to the above configuration, a voltage corresponding to a desired voltage (Vd) can be stored as an initial voltage in the storage unit (65), thereby enabling the correction circuit (5) to generate a correction voltage (Vh) such that the magnitude of the output voltage (Vout) input to the correction circuit (5) approaches the desired voltage (Vd).

[0088] A program according to a seventh aspect is a program readable by a computer system, and causes one or more processors of the computer system to execute the setting method according to the sixth aspect.

[0089] According to the above configuration, a voltage corresponding to a desired voltage (Vd) can be stored as an initial voltage in the storage unit (65), thereby enabling the correction circuit (5) to generate a correction voltage (Vh) such that the magnitude of the output voltage (Vout) input to the correction circuit (5) approaches the desired voltage (Vd).

[0090] Not limited to the above aspects, various configurations (including modified examples) of the voltage conversion unit (1) according to the embodiment can be embodied as a setting method, a (computer) program, or a non-transitory recording medium on which a program is recorded.

[0091] REFERENCE SIGNS LIST 1 Voltage conversion unit 2 Voltage control section 3 Voltage comparison section 4 Voltage divider circuit 5 Correction circuit 6 Correction information calculation section 7 Correction voltage generation section 8 Control system 21 Input terminal 22 Output terminal 41 First resistor 42 Second resistor 43 Connection point 65 Memory section 75 Smoothing circuit 76 Operational amplifier S2 PWM signal Vc Comparison voltage Vd Desired voltage Vh Correction voltage Vin Input voltage Vout Output voltage Vref Reference voltage

Claims

1. A voltage control unit having an input terminal and an output terminal, which generates a DC output voltage to be output from the output terminal based on a DC input voltage input to the input terminal; a voltage comparison unit which controls the magnitude of the output voltage of the voltage control unit in accordance with a difference between a reference voltage and a comparison voltage; a voltage divider circuit electrically connected to the output terminal of the voltage control unit; and a correction circuit electrically connected to the output terminal of the voltage control unit, wherein the voltage divider circuit has a first resistor and a second resistor, a first end of the first resistor electrically connected to the output terminal of the voltage control unit, a second end of the first resistor electrically connected to the first end of the second resistor, and a second end of the second resistor electrically connected to ground, and the voltage divider circuit outputs the comparison voltage, which is the voltage at the connection point between the second end of the first resistor and the first end of the second resistor, to the voltage comparison unit, The correction circuit generates a correction voltage based on a comparison result between the output voltage of the voltage control unit and an initial voltage stored in a storage unit, and outputs the correction voltage to the connection point.

2. The voltage conversion unit of claim 1, wherein the correction circuit comprises: a correction information calculation unit that generates correction information based on a comparison result between the output voltage of the voltage control unit and the initial voltage stored in the memory unit; and a correction voltage generation unit that is electrically connected to the connection point, generates the correction voltage based on the correction information, and outputs the correction voltage to the connection point.

3. The voltage conversion unit according to claim 2, wherein the correction information calculation unit outputs the correction information as a PWM signal, and the correction voltage generation unit comprises: a smoothing circuit that smoothes the PWM signal; and an operational amplifier that amplifies the signal output from the smoothing circuit to generate the correction voltage and outputs the correction voltage to the connection point.

4. The voltage conversion unit according to claim 3, wherein the correction information calculation section increases the duty of the PWM signal when the output voltage of the voltage control section is greater than the initial voltage stored in the storage section.

5. The voltage conversion unit according to claim 3, wherein the correction information calculation section reduces the duty of the PWM signal when the output voltage of the voltage control section is smaller than the initial voltage stored in the storage section.

6. A setting method for a voltage conversion unit as described in claim 1, comprising: a first step in which a control system applies a desired voltage to the output terminal of the voltage control unit when operation of the voltage control unit is stopped; and a second step in which, when the desired voltage has been applied to the output terminal of the voltage control unit in the first step, the control system stores the measured value of the desired voltage input to the correction circuit in the memory unit as the initial voltage.

7. A program readable by a computer system, causing one or more processors of said computer system to execute the setting method according to claim 6.

8. A non-transitory recording medium on which a program for causing one or more processors of a computer system to execute the setting method according to claim 6 is recorded.

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