DCDC system with low-power DCDC and high-power DCDC cooperatively working

Abstract

The utility model discloses a DCDC system with low-power and high-power DCDC cooperative work. The DCDC system comprises a high-power isolation DCDC unit, a low-power isolation DCDC unit and an MCU unit. The MCU unit is respectively connected with the high-power isolation DCDC unit and the low-power isolation DCDC unit; a current detection amplification unit, an enabling output control circuit, a temperature acquisition circuit and a short-circuit protection circuit are also connected between the MCU unit and the high-power isolation DCDC unit; according to the utility model, the high-power isolation DCDC unit, the low-power isolation DCDC unit and the MCU unit are arranged, through comprehensive analysis of performance parameters of a load to be supplied with power and voltage and current of the load to be supplied with power, the process of supplying power to the load by the DCDC is accurately controlled, and the power supply efficiency, quality and reliability of the high-power DCDC are improved; meanwhile, the problem of insufficient power supply due to the fact that a storage battery is adopted to supply power to the load originally is solved, the power supply efficiency is improved, and the load is kept in an electrified state.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to a dual-system DCDC power supply for electric vehicles, electric special vehicles and electric beach vehicles, in which low-power and high-power DCDC work in coordination. Background Art

[0002] Since the advent of high-power DCDC, it has been widely used in various electronic fields, such as high-power power supplies, instruments, energy storage equipment, and new energy electric vehicles. At present, electric low-speed vehicles, special vehicles, electric sightseeing vehicles, electric beach vehicles, etc. all use DCDC converters to power low-voltage electrical appliances on the vehicle. Different vehicle electrical appliances have different power DCDC converters. The defects of existing DCDC converters are: when the car is parked, the power supply of the control signal is powered by a small lead-acid battery. On the one hand, the life of the lead-acid battery itself is short, generally 2-3 years. On the other hand, using a small battery to charge the high-power DCDC, long-term parking can easily cause the power to run out, resulting in the vehicle being unable to start, and the cost of replacing lithium batteries is high.

[0003] In order to solve some of the shortcomings of the above-mentioned lead-acid batteries, the present application has developed a DCDC system in which low-power and high-power DCDC work together; the traditional lead-acid starting small battery can be eliminated, the cost of the entire vehicle is reduced, and the power consumption is also small. Utility Model Content

[0004] The utility model aims to provide a DCDC system in which low-power and high-power DCDC work in coordination, so as to solve the problems existing in the background technology.

[0005] To solve this technical problem, the technical solution of the utility model is:

[0006] A DCDC system in which low-power and high-power DCDC work in coordination, comprising a high-power isolated DCDC unit, a low-power isolated DCDC unit and an MCU unit;

[0007] The MCU unit is connected to the high-power isolated DCDC unit and the low-power isolated DCDC unit respectively; a current detection amplifier unit, an enable output control circuit, a temperature acquisition circuit and a short-circuit protection circuit are also connected between the MCU unit and the high-power isolated DCDC unit; a photoelectric isolation control circuit is also connected between the MCU unit and the low-power isolated DCDC unit;

[0008] The MCU unit is also connected to an ON enable input circuit and a voltage stabilizing circuit unit;

[0009] Among them, the high-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the low-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the current detection amplifier unit is used to collect the operating current of the high-power isolated DCDCC; the MCU unit is used to control the high-power isolated DCDC unit after data acquisition, analysis and processing of the ON enable input circuit, enable output control circuit, temperature acquisition circuit, current detection circuit, short-circuit protection circuit and isolation control circuit; the voltage stabilizing circuit unit is used to provide power supply voltage for the MCU unit; the photoelectric isolation control unit is used to detect the working state of the low-power isolated DCDC unit and is processed and analyzed by the MCU unit.

[0010] Preferably, the power of the high-power isolated DCDC unit is 500W, and the power of the low-power isolated DCDC unit is 10W.

[0011] Preferably, the high-power isolated DCDC unit includes a 500W isolated DCDC module and an input filter capacitor C1, a constantan wire sampling resistor and an output filter capacitor C4 connected to the outside of the 500W isolated DCDC module, the positive electrode of the input filter capacitor C1 is connected to the positive electrode of the 48-72V power supply, the first end of the constantan wire sampling resistor is connected to the negative electrode of the 48-72V power supply, and the second end is connected to the negative electrode of the input filter capacitor C1 and the negative electrode of the high-power isolated DCDC unit; the power output end of the 500W isolated DCDC module is respectively connected to the positive and negative electrodes of the output filter capacitor C4, and the positive electrode of the output filter capacitor C4 is also connected to the positive electrode of the load.

[0012] Preferably, the low-power isolated DCDC unit includes a 10W isolated DCDC module and an output filter capacitor C5 and a diode D1 connected to the outside of the 10W isolated DCDC module. The power input end of the 10W isolated DCDC module is respectively connected to the positive and negative electrodes of the 48-72V power supply, and the output end is respectively connected to +12V and GND; the positive electrode of the filter capacitor C5 is connected to the anode of the diode D1, and the negative electrode is connected to GND, and the cathode of the diode D1 is connected to the positive electrode of the load.

[0013] Among them, the 500W isolated DCDC module and the 10W isolated DCDC module both include corresponding isolated DCDC modules and transformers; they are existing products and will not be described in detail here;

[0014] Preferably, the current detection amplifier circuit includes an amplifier, wherein the input terminals 3 and 1 of the amplifier are respectively connected to the two ends of the constantan wire sampling resistor, and the output terminal 4 is connected to the MCU unit.

[0015] Preferably, the ON enable input circuit includes a resistor R2, a resistor R3 and a transistor Q1, the first end of the resistor R3 is connected to the ON signal, and the second end is connected to the base of the transistor Q1, the first end of the resistor R2 is connected to +5V, and the second end is connected to the collector of the transistor Q1, the emitter of the transistor Q1 is connected to the negative pole of the power supply, and the collector of the transistor Q1 is also connected to the ON enable control pin of the MCU unit.

[0016] Preferably, the voltage stabilizing circuit unit includes a transient suppression diode TV1, a filter capacitor C2, a filter capacitor C3 and a voltage stabilizing LDO module; one end of the transient suppression diode TV1 is connected to the positive electrode of the 48-72V power supply, and the other end is connected to the negative electrode of the 48-72V power supply; the positive and negative electrodes of the filter capacitor C2 are connected in parallel with the two ends of the transient suppression diode TV1, and the positive and negative electrodes of the filter capacitor C2 are also connected to the input end of the voltage stabilizing LDO module; the negative electrode of the filter capacitor C2 is also connected to the VSS end, and the positive and negative electrodes of the filter capacitor C3 are respectively connected to the output end +5V and the VSS end of the voltage stabilizing LDO module.

[0017] Preferably, the photoelectric isolation control unit includes a photoelectric coupler U2, a resistor R4, a resistor R5, and a resistor R6; one end of the resistor R5 is connected to +5V, and the other end is connected to the photoelectric coupler U24 pin and the MCU unit; one end of the resistor R4 is connected to the output end +12V of the low-power isolation DCDC unit, and the other end is connected to the photoelectric coupler pin 1; the two ends of the resistor R6 are respectively connected to the photoelectric coupler pin 1 and pin 2; the photoelectric coupler pin 3 is connected to VSS.

[0018] The above technical solution and the beneficial effects of the utility model are:

[0019] The utility model is provided with a high-power isolated DCDC unit, a low-power isolated DCDC unit and an MCU unit, and realizes accurate control of the process of DCDC supplying power to the load by comprehensively analyzing the performance parameters of the load to be powered and the voltage and current of the load to be powered, thereby improving the efficiency, quality and reliability of the high-power DCDC power supply; at the same time, it also solves the problem of insufficient power supply when the battery is used to supply power to the load, improves the power supply efficiency, and thus keeps the load in a charged state. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the principle structure of the utility model. DETAILED DESCRIPTION

[0021] like Figure 1 As shown, in order to further explain the technical solution of the present invention, the present invention is described in detail through specific embodiments below.

[0022] Example 1

[0023] The utility model discloses a DCDC system in which low-power and high-power DCDC work in coordination, comprising a high-power isolated DCDC unit, a low-power isolated DCDC unit and an MCU unit;

[0024] The MCU unit is connected to the high-power isolated DCDC unit and the low-power isolated DCDC unit respectively; a current detection amplifier unit, an enable output control circuit, a temperature acquisition circuit and a short-circuit protection circuit are also connected between the MCU unit and the high-power isolated DCDC unit; a photoelectric isolation control circuit is also connected between the MCU unit and the low-power isolated DCDC unit;

[0025] The MCU unit is also connected to an ON enable input circuit and a voltage stabilizing circuit unit;

[0026] Among them, the high-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the low-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the current detection amplifier unit is used to collect the operating current of the high-power isolated DCDCC; the MCU unit is used to control the high-power isolated DCDC unit after data acquisition, analysis and processing of the ON enable input circuit, enable output control circuit, temperature acquisition circuit, current detection circuit, short-circuit protection circuit and isolation control circuit; the voltage stabilizing circuit unit is used to provide power supply voltage for the MCU unit; the photoelectric isolation control unit is used to detect the working state of the low-power isolated DCDC unit and is processed and analyzed by the MCU unit.

[0027] Among them, the power of the high-power isolation DCDC unit is 500W, and the power of the low-power isolation DCDC unit is 10W.

[0028] In this embodiment, the high-power isolated DCDC unit includes a 500W isolated DCDC module and an input filter capacitor C1, a constantan wire sampling resistor and an output filter capacitor C4 connected to the outside of the 500W isolated DCDC module, the positive electrode of the input filter capacitor C1 is connected to the positive electrode of the 48-72V power supply, the first end of the constantan wire sampling resistor is connected to the negative electrode of the 48-72V power supply, and the second end is connected to the negative electrode of the input filter capacitor C1 and the negative electrode of the high-power isolated DCDC unit; the power output end of the 500W isolated DCDC module is respectively connected to the positive and negative electrodes of the output filter capacitor C4, and the positive electrode of the output filter capacitor C4 is also connected to the positive electrode of the load.

[0029] The low-power isolated DCDC unit includes a 10W isolated DCDC module and an output filter capacitor C5 and a diode D1 connected to the outside of the 10W isolated DCDC module. The power input end of the 10W isolated DCDC module is respectively connected to the positive and negative electrodes of the 48-72V power supply, and the output end is respectively connected to +12V and GND; the positive electrode of the filter capacitor C5 is connected to the anode of the diode D1, and the negative electrode is connected to GND, and the cathode of the diode D1 is connected to the positive electrode of the load.

[0030] Among them, the 500W isolated DCDC module and the 10W isolated DCDC module both include corresponding isolated DCDC modules and transformers; they are existing products and will not be described in detail here;

[0031] The current detection amplifier circuit includes an amplifier, wherein the input terminals 3 and 1 of the amplifier are respectively connected to the two ends of the constantan wire sampling resistor, and the output terminal 4 is connected to the MCU unit. The ON enable input circuit includes a resistor R2, a resistor R3 and a transistor Q1. The first end of the resistor R3 is connected to the ON signal, and the second end is connected to the base of the transistor Q1. The first end of the resistor R2 is connected to +5V, and the second end is connected to the collector of the transistor Q1. The emitter of the transistor Q1 is connected to the negative electrode of the power supply, and the collector of the transistor Q1 is also connected to the ON enable control pin of the MCU unit. In this embodiment, the voltage stabilizing circuit unit is a 5V voltage stabilizing circuit unit; the voltage stabilizing circuit unit includes a transient suppression diode TV1, a filter capacitor C2, a filter capacitor C3 and a voltage stabilizing LDO module; one end of the transient suppression diode TV1 is connected to the positive electrode of the 48-72V power supply, The other end is connected to the negative electrode of the 48-72V power supply; the positive and negative electrodes of the filter capacitor C2 are connected in parallel with the two ends of the transient suppression diode TV1, and the positive and negative electrodes of the filter capacitor C2 are also connected to the input end of the voltage-stabilizing LDO module; the negative electrode of the filter capacitor C2 is also connected to the VSS end, the positive and negative electrodes of the filter capacitor C3 are respectively connected to the output ends +5V and VSS of the voltage-stabilizing LDO module, and the optoelectronic isolation control unit includes an optocoupler U2, a resistor R4, a resistor R5, and a resistor R6; one end of the resistor R5 is connected to +5V, and the other end is connected to the 4th foot of the optocoupler U2 and the MCU unit; one end of the resistor R4 is connected to the output end +12V of the low-power isolation DCDC unit, and the other end is connected to the 1st foot of the optocoupler; the two ends of the resistor R6 are respectively connected to the 1st foot and the 2nd foot of the optocoupler; the 3rd foot of the optocoupler is connected to VSS.

[0032] The working principle of this application is:

[0033] The 48-72V power supply supplies power to the MCU through a 5V voltage regulator circuit, and the MCU collects the voltage of each port to execute operation instructions;

[0034] Startup circuit: Since the flexible load of the small-power isolated DCDC is small and the load capacitance of the 500W isolated DCDC is large, the small-power DCDC output 12V hiccups, the 1st and 4th pins of the photocoupler U2 change with the change of the small-power DCDC, and the DCDC enable pin outputs a high level to turn on the 500W DCDC, outputting 13.8V to charge the filter capacitor C4 until the small-power DCDC 12V voltage stabilizes, the photocoupler 4th pin is low, the MCU enable pin is low, the 500W DCDC is turned off, and the load is powered by the small-power DCDC.

[0035] Working status: Turn on the ON switch, 12V voltage is added to R3 through the ON switch, transistor Q1 is turned on, ON enable is low level, DCDC enable pin is high level, and 500W DCDC is turned on to provide high power current to the load.

[0036] Short circuit protection: The amplifier detects the voltage across the constantan wire sampling resistor. After differential amplification by the amplifier, the MCU detects the set AD value. The short circuit protection of the other port of the MCU outputs a high level to control the power supply of the 500W DCDC pulse width control chip, turn off the power supply, and stop the output of the 500W DCDC until the load short circuit is released and the circuit returns to normal working state.

[0037] Temperature protection: The MCU detects the AD value of the temperature sensor and outputs a high level to control the 500W DCDC pulse width control chip, so that the 500W DCDC power decreases until the temperature drops and the circuit returns to normal working state.

[0038] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A DCDC system in which low power and high power DCDC work together, characterized in that: Including high-power isolated DCDC unit, low-power isolated DCDC unit and MCU unit; The MCU unit is connected to the high-power isolated DCDC unit and the low-power isolated DCDC unit respectively; a current detection amplifier unit, an enable output control circuit, a temperature acquisition circuit and a short-circuit protection circuit are also connected between the MCU unit and the high-power isolated DCDC unit; a photoelectric isolation control circuit is also connected between the MCU unit and the low-power isolated DCDC unit; The MCU unit is also connected to an ON enable input circuit and a voltage stabilizing circuit unit; Among them, the high-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the low-power isolated DCDC unit is used to generate the voltage and current required by the load through the secondary rectification and filtering of the converter by the primary high voltage, and supply power to the load; the current detection amplifier unit is used to collect the operating current of the high-power isolated DCDCC; the MCU unit is used to control the high-power isolated DCDC unit after data acquisition, analysis and processing of the ON enable input circuit, enable output control circuit, temperature acquisition circuit, current detection circuit, short-circuit protection circuit and isolation control circuit; the voltage stabilizing circuit unit is used to provide power supply voltage for the MCU unit; the photoelectric isolation control unit is used to detect the working state of the low-power isolated DCDC unit and is processed and analyzed by the MCU unit.

2. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The power of the high-power isolated DCDC unit is 500W, and the power of the low-power isolated DCDC unit is 10W.

3. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The high-power isolated DCDC unit includes a 500W isolated DCDC module and an input filter capacitor C1, a constantan wire sampling resistor and an output filter capacitor C4 connected to the outside of the 500W isolated DCDC module, the positive electrode of the input filter capacitor C1 is connected to the positive electrode of the 48-72V power supply, the first end of the constantan wire sampling resistor is connected to the negative electrode of the 48-72V power supply, and the second end is connected to the negative electrode of the input filter capacitor C1 and the negative electrode of the high-power isolated DCDC unit; the power output end of the 500W isolated DCDC module is respectively connected to the positive electrode and negative electrode of the output filter capacitor C4, and the positive electrode of the output filter capacitor C4 is also connected to the positive electrode of the load.

4. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The low-power isolated DCDC unit includes a 10W isolated DCDC module and an output filter capacitor C5 and a diode D1 connected to the outside of the 10W isolated DCDC module. The power input end of the 10W isolated DCDC module is respectively connected to the positive and negative electrodes of the 48-72V power supply, and the output end is respectively connected to +12V and GND; the positive electrode of the filter capacitor C5 is connected to the anode of the diode D1, and the negative electrode is connected to GND, and the cathode of the diode D1 is connected to the positive electrode of the load.

5. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The current detection amplifier circuit includes an amplifier, wherein the input terminals 3 and 1 of the amplifier are respectively connected to the two ends of the constantan wire sampling resistor, and the output terminal 4 is connected to the MCU unit.

6. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The ON enable input circuit includes resistor R2, resistor R3 and transistor Q1. The first end of resistor R3 is connected to the ON signal, and the second end is connected to the base of transistor Q1. The first end of resistor R2 is connected to +5V, and the second end is connected to the collector of transistor Q1. The emitter of transistor Q1 is connected to the negative pole of the power supply, and the collector of transistor Q1 is also connected to the ON enable control pin of the MCU unit.

7. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The voltage stabilizing circuit unit includes a transient suppression diode TV1, a filter capacitor C2, a filter capacitor C3 and a voltage stabilizing LDO module; one end of the transient suppression diode TV1 is connected to the positive electrode of the 48-72V power supply, and the other end is connected to the negative electrode of the 48-72V power supply; the positive and negative electrodes of the filter capacitor C2 are connected in parallel with the two ends of the transient suppression diode TV1, and the positive and negative electrodes of the filter capacitor C2 are also connected to the input end of the voltage stabilizing LDO module; the negative electrode of the filter capacitor C2 is also connected to the VSS end, and the positive and negative electrodes of the filter capacitor C3 are respectively connected to the output end +5V and VSS end of the voltage stabilizing LDO module.

8. A DCDC system in which low-power and high-power DCDC work in coordination according to claim 1, characterized in that: The photoelectric isolation control unit includes a photoelectric coupler U2, a resistor R4, a resistor R5, and a resistor R6; One end of resistor R5 is connected to +5V, and the other end is connected to pin 4 of optocoupler U2 and MCU unit; one end of resistor R4 is connected to the output terminal +12V of low-power isolation DCDC unit, and the other end is connected to pin 1 of optocoupler; both ends of resistor R6 are connected to pin 1 and pin 2 of optocoupler respectively; pin 3 of optocoupler is connected to VSS.

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