Comprehensive detection unit

Abstract

The utility model discloses a comprehensive detection unit, which comprises an MCU (Microprogrammed Control Unit), an alternating-current voltage detection module, a direct-current voltage detection module, a direct-current current detection module and a temperature detection module. The alternating current voltage detection module is electrically connected with the MCU and is used for collecting one path of direct current to ground alternating current voltage and at least one path of three-phase alternating current voltage; the direct-current voltage detection module is electrically connected with the MCU and is used for sampling one path of insulation voltage and at least one path of direct-current voltage; the current detection module is electrically connected with the MCU; and the temperature detection module is electrically connected with the MCU. According to the utility model, two paths of three-phase AC voltage and one path of DC-to-ground AC voltage are collected, isolated and collected signals are respectively transmitted to each pin of the metering chip U4 through the current-limiting resistor and the filter capacitor, and then the metering chip U4 converts the signals into digital signals and transmits the digital signals to the MCU; and the frequency and the power factor of the AC voltage can be calculated while the AC voltage is processed and read by the MCU.

Description

Technical Field

[0001] The utility model relates to the technical field of battery detection, in particular to a comprehensive detection unit. Background Art

[0002] With the advancement of technology and the large-scale access of renewable energy (such as wind power and solar energy) to the power grid, large-scale DC systems are increasingly being used to transmit electricity from renewable energy power generation sites far away from cities to city centers. At present, the detection of large-scale DC systems includes parameters such as voltage, current, and temperature, and DC detection units play multiple important roles in large-scale DC systems, such as monitoring, protection, control, data acquisition, and transmission. They are key components to ensure the safe and stable operation of large-scale DC systems.

[0003] Ordinary DC detection units have a single function and can only perform voltage detection or current detection. They cannot measure voltage, current and temperature at the same time, and cannot independently detect data and transmit in real time, and cannot perform remote control. They cannot play a role in predictive maintenance and fault location for daily maintenance of DC systems, wasting manpower and material resources.

[0004] Therefore, it is necessary to improve the existing battery detection circuit. Utility Model Content

[0005] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a comprehensive detection unit. The purpose of designing the comprehensive detection unit is to realize the communication and function detection of a large-scale DC system on the same circuit board, meet the accuracy requirements of various parameters of the large-scale DC system, and improve the detection efficiency in real time and high efficiency.

[0006] In order to solve the above technical problems, the utility model is implemented by the following scheme: a comprehensive detection unit of the utility model includes an MCU and also includes:

[0007] An AC voltage detection module electrically connected to the MCU and used to collect an AC voltage from one DC to the ground and at least one three-phase AC voltage;

[0008] A DC voltage detection module electrically connected to the MCU and used for sampling one insulation voltage and at least one DC voltage;

[0009] A DC current detection module electrically connected to the MCU;

[0010] A temperature detection module electrically connected to the MCU.

[0011] Furthermore, the MCU is a single chip microcomputer with flash memory and RAM, and the single chip microcomputer supports ISP programming and IAP programming.

[0012] Furthermore, the AC voltage detection module includes a metering chip U4 and seven groups of isolated sensor circuits electrically connected to the metering chip U4. Among the seven groups of isolated sensor circuits, one group of isolated sensor circuits collects DC from the earth's AC power, and the other six groups are divided into two collection circuits, which collect two three-phase voltages respectively.

[0013] Furthermore, any set of isolated sensing circuits includes a sensor TP, seven resistors and two first capacitors;

[0014] In any group of isolated sensor circuits, the first end of the primary coil of the sensor TP is connected to a series circuit consisting of three first resistors, two second resistors connected in series are connected between the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP, the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP are both connected to a third resistor, the other ends of the two third resistors are both connected to a first capacitor, and the other ends of the first capacitors are connected to each other and grounded;

[0015] In the two-way three-phase voltage acquisition circuit, the other end of the series circuit is connected to the live wire, and the second end of the primary coil of the sensor TP is connected to the neutral wire.

[0016] In the ground AC power collection circuit, the other end of the series circuit is connected to the PE ground, and the second end of the primary coil of the sensor TP is connected to the PE2 ground.

[0017] Furthermore, in each isolation sensor circuit, an isolated and collected signal is generated between the third resistor and the first capacitor connected to the third resistor, and each signal is connected one-to-one to the signal receiving pin of the metering chip U4 and a digital signal is generated by the metering chip U4;

[0018] The 38-pin DOUT of the metering chip U4, the 37-pin DIN of the metering chip U4, the 36-pin SCLK of the metering chip U4, and the 35-pin CS of the metering chip U4 are connected one-to-one to the signal receiving pins of the MCU.

[0019] Furthermore, the DC voltage detection module includes five DC voltage sampling circuits and one insulation voltage sampling circuit;

[0020] The DC voltage sampling circuit includes a first step-down circuit and a first RC current limiting filter circuit connected to the first step-down circuit, and the first RC current limiting filter circuit is connected to the ADC of the MCU;

[0021] The insulation voltage sampling circuit includes a second step-down circuit and a second RC current limiting filter circuit connected to the second step-down circuit.

[0022] Furthermore, the DC current detection module includes an operational amplifier U5A, an operational amplifier U5B, an operational amplifier U6B, a plurality of resistors, and a plurality of capacitors;

[0023] The in-phase input terminal of the operational amplifier U5A is connected to a resistor R132, and the resistor R132 is connected to a temperature detection module;

[0024] The inverting input terminal of the operational amplifier U5A is connected to the first end of the resistor R133, the first end of the resistor R131, and the output terminal of the operational amplifier U5A;

[0025] The non-inverting input terminal of the operational amplifier U5B is connected to the first end of the resistor R134 and the first end of a first RC circuit, the second end of the resistor R134 is connected to the MCU, the second end of the first RC circuit is grounded, and the first RC circuit includes a capacitor C56 and a resistor R136 connected in parallel;

[0026] The inverting input terminal of the operational amplifier U5B is connected to the output terminal of the operational amplifier U5B and the first end of the resistor R135, the second end of the resistor R135 is respectively connected to the second end of the resistor R131 and the first end of the capacitor C55, and the second end of the capacitor C55 is grounded;

[0027] The non-inverting input terminal of the operational amplifier U6B is connected to the first end of the resistor R137 and the first end of the second RC circuit, the second end of the resistor R137 is connected to the MCU, the second end of the second RC circuit is grounded, and the second RC circuit includes a resistor R139 and a capacitor C58 connected in parallel;

[0028] The inverting input terminal of the operational amplifier U6B is connected to the output terminal of the operational amplifier U6B, the output terminal of the operational amplifier U6B is connected to the first end of the resistor R138, the second end of the resistor R138 is connected to the second end of the resistor R133 and the first end of the capacitor C57, and the second end of the capacitor C57 is grounded.

[0029] Compared with the prior art, the beneficial effects of the utility model are:

[0030] 1. The comprehensive detection unit of the utility model can monitor system voltage, current, temperature and other parameters in real time to improve the reliability and safety of system operation.

[0031] 2. The comprehensive detection unit of the utility model can automatically manage two AC lines, detect the six-phase voltage, and detect the over-voltage, under-voltage, phase loss and other alarms of the two AC lines in real time.

[0032] 3. The AC voltage detection module of the utility model is composed of a high-precision isolation sensor, a high-precision metering chip U4, and a plurality of capacitors and resistors to form an acquisition circuit. By collecting two three-phase AC voltages and one DC voltage to the earth, the isolated and collected signals are respectively transmitted to each pin of the metering chip U4 through the current limiting resistor and the filter capacitor, and then converted into a digital signal by the metering chip U4 and transmitted to the MCU. The AC voltage is read through the MCU processing and the frequency and power factor of the AC voltage can also be calculated. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the principle block diagram of the comprehensive detection unit of the utility model.

[0034] Figure 2-Figure 3 After connection, the circuit diagram of the AC voltage detection module of the utility model is formed.

[0035] Figure 4 This is a circuit diagram of the DC voltage detection module of the utility model.

[0036] Figure 5 This is a circuit diagram of the DC current detection module of the utility model.

[0037] Figure 6 This is a circuit diagram of the temperature detection module of the utility model. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model, so that the advantages and features of the utility model can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the protection scope of the utility model. Obviously, the embodiments described in the utility model are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0039] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Embodiment 1: The specific structure of the utility model is as follows:

[0041] Please refer to the attached Figure 1-5The utility model discloses a comprehensive detection unit, including an MCU, wherein the MCU adopts a single-chip microcomputer with flash memory and RAM, and the single-chip microcomputer supports ISP programming and IAP programming. The model of the MCU adopted is STC8A8K32S4. The STC8A8K32S4 chip is an 8-bit single-chip microcomputer based on the 8051 core. This single-chip microcomputer has 8KB of flash memory and 256 bytes of RAM, supports ISP and IAP programming, and is suitable for various low-end and mid-end embedded control systems. It has built-in multiple peripheral interfaces, such as UART serial port, timer / counter, PWM output, etc., as well as rich I / O ports, making it an ideal choice for home appliances, industrial control, intelligent instruments and other fields. STC8A8K32S4 is widely used for its high performance, low power consumption and easy development.

[0042] A comprehensive detection unit of the utility model also includes:

[0043] An AC voltage detection module electrically connected to the MCU and used to collect an AC voltage from one DC to the ground and at least one three-phase AC voltage;

[0044] A DC voltage detection module electrically connected to the MCU and used for sampling one insulation voltage and at least one DC voltage;

[0045] A DC current detection module electrically connected to the MCU;

[0046] A temperature detection module electrically connected to the MCU.

[0047] like Figure 2-3 As shown, Figure 2-Figure 3 After connection, the circuit diagram of the AC voltage detection module of the utility model is formed.

[0048] A preferred technical solution of this embodiment: the AC voltage detection module includes a metering chip U4 and seven groups of isolation sensor circuits electrically connected to the metering chip U4. Among the seven groups of isolation sensor circuits, one group of isolation sensor circuits is for DC to earth AC power collection, and the other six groups are divided into two collection circuits, and the two collection circuits collect two three-phase voltages respectively.

[0049] Any set of isolated sensing circuits includes a sensor TP, seven resistors and two first capacitors.

[0050] like Figure 2In the circuit of sensor TP1, for example, the first end of the primary coil of sensor TP1 is connected to the first end of resistor R47, the second end of resistor R47 is connected to the first end of resistor R51, the second end of resistor R51 is connected to the first end of resistor R55, and the second end of resistor R55 is connected to the live wire VA1. The second end of the primary coil of sensor TP1 is connected to the neutral wire VN1. The two ends of the secondary coil of the sensor TP1 are connected in series with resistor R53 and resistor R57. From the first end of the secondary coil of the sensor TP1 to the first end of the secondary coil of the sensor TP1, resistor R49, capacitor C24, capacitor C26, and resistor R59 are also connected in series. The circuit node between the capacitor C24 and the capacitor C26 is grounded.

[0051] like Figure 2-3 As shown, the collection point VIN between the resistor R49 and the capacitor C24 is connected to the 4th pin VIN of the metering chip U4. The collection point VIP between the resistor R59 and the capacitor C26 is connected to the 3rd pin VIP of the metering chip U4.

[0052] like Figure 2-3 The other six groups of sensors TP shown have the same circuit structure as the sensor TP1, and the collection points are correspondingly connected to the pins of the metering chip U4.

[0053] In any group of isolated sensor circuits, the first end of the primary coil of the sensor TP is connected to a series circuit consisting of three first resistors, two second resistors connected in series are connected between the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP, the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP are both connected to a third resistor, the other ends of the two third resistors are both connected to a first capacitor, and the other ends of the first capacitors are connected to each other and grounded;

[0054] In the two-way three-phase voltage acquisition circuit, the other end of the series circuit is connected to the live wire, and the second end of the primary coil of the sensor TP is connected to the neutral wire.

[0055] In the ground AC power collection circuit, the other end of the series circuit is connected to the PE ground, and the second end of the primary coil of the sensor TP is connected to the PE2 ground.

[0056] A preferred technical solution of this embodiment: in each isolation sensor circuit, an isolated and collected signal is generated between the third resistor and the first capacitor connected to the third resistor, and each signal is connected one-to-one to the signal receiving pin of the metering chip U4 and a digital signal is generated by the metering chip U4;

[0057] The 38-pin DOUT of the metering chip U4, the 37-pin DIN of the metering chip U4, the 36-pin SCLK of the metering chip U4, and the 35-pin CS of the metering chip U4 are connected one-to-one to the signal receiving pins of the MCU.

[0058] The AC voltage detection module's AC voltage collection is mainly composed of high-precision isolation sensors, isolation sensors TP1, TP2, TP3, TP4, TP5, TP6, TP7, high-precision metering chip U4 and other resistors and capacitors. This circuit can collect two three-phase AC voltages and one DC voltage to the earth. Figure 2 As shown, the first VN1, VA1 VB1 VC1, are the neutral line and the A phase, B phase and C phase live wire respectively. The second VN2, VA2 VB2 VC2, are the neutral line and the A phase, B phase and C phase live wire respectively. The DC to the earth AC power collection is PE, PE2. The isolation sensor can reach an isolation withstand voltage of 3KV, and the isolated collected signals: V1N, VIP, V2N, V2P, V3N, V3P, V4NV4P, V5N, V5P, V6N, V6P, V7N, V7P, through the current limiting resistor and the filter capacitor, are respectively sent to each pin of U4, and then the digital signals of the 38th pin DOUT of the metering chip U4, the 37th pin DIN of the metering chip U4, the 36th pin SCLK of the metering chip U4, and the 35th pin CS of the metering chip U4 are transmitted to the main MCU, and the AC voltage is read through the program processing, and the frequency and power factor of the AC voltage can also be calculated.

[0059] A preferred technical solution of this embodiment: the DC voltage detection module includes five DC voltage sampling circuits and one insulation voltage sampling circuit;

[0060] The DC voltage sampling circuit includes a first step-down circuit and a first RC current limiting filter circuit connected to the first step-down circuit, and the first RC current limiting filter circuit is connected to the ADC of the MCU;

[0061] The insulation voltage sampling circuit includes a second step-down circuit and a second RC current limiting filter circuit connected to the second step-down circuit.

[0062] A preferred technical solution of this embodiment: the DC current detection module includes an operational amplifier U5A, an operational amplifier U5B, an operational amplifier U6B, a plurality of resistors, and a plurality of capacitors;

[0063] The in-phase input terminal of the operational amplifier U5A is connected to a resistor R132, and the resistor R132 is connected to a temperature detection module;

[0064] The inverting input terminal of the operational amplifier U5A is connected to the first end of the resistor R133, the first end of the resistor R131, and the output terminal of the operational amplifier U5A;

[0065] The non-inverting input terminal of the operational amplifier U5B is connected to the first end of the resistor R134 and the first end of a first RC circuit, the second end of the resistor R134 is connected to the MCU, the second end of the first RC circuit is grounded, and the first RC circuit includes a capacitor C56 and a resistor R136 connected in parallel;

[0066] The inverting input terminal of the operational amplifier U5B is connected to the output terminal of the operational amplifier U5B and the first end of the resistor R135, the second end of the resistor R135 is respectively connected to the second end of the resistor R131 and the first end of the capacitor C55, and the second end of the capacitor C55 is grounded;

[0067] The non-inverting input terminal of the operational amplifier U6B is connected to the first end of the resistor R137 and the first end of the second RC circuit, the second end of the resistor R137 is connected to the MCU, the second end of the second RC circuit is grounded, and the second RC circuit includes a resistor R139 and a capacitor C58 connected in parallel;

[0068] The inverting input terminal of the operational amplifier U6B is connected to the output terminal of the operational amplifier U6B, the output terminal of the operational amplifier U6B is connected to the first end of the resistor R138, the second end of the resistor R138 is connected to the second end of the resistor R133 and the first end of the capacitor C57, and the second end of the capacitor C57 is grounded.

[0069] The DC current detection module has 5 DC voltage sampling channels and 1 insulation voltage sampling channel. The sampling resistor uses a 0.5% precision low temperature drift resistor for voltage division. After voltage division, it is filtered by resistor and capacitor current limiting to the main MCU ADC. The circuit of the DC current detection module can collect two battery current sampling circuits and support the input of multiple signals, such as: current Hall sensor, shunt, sampling resistor, etc. It can collect the battery charging and discharging current, that is, positive current during charging and negative current during discharging. BTI and BTI2 are input signals. After being followed by the precision op amp, they are filtered by resistor R138, resistor R135, current limiting capacitor C57, and current limiting capacitor C55 to the MCU ADC.

[0070] like Figure 6 As shown, the comprehensive detection unit of the utility model also includes a temperature detection module connected to the MCU: the temperature detection of the DC system is usually achieved by using an NTC thermistor. The resistance of the thermistor decreases as the temperature increases. OUT1 Connect the ADC channel of the MCU's P1.3 pin to the DC system to form a voltage divider circuit. OUT1Perform multiple sampling, filtering, quantization and conversion to obtain the sampled value ADC TEMP , the sampled value ADC is converted into TEMP Compared with the NTC resistance table, when NTC A

[0071] The utility model comprehensive detection unit also includes an RS485 communication module connected to the MCU: TXD2 (P4.2), RXD2 (P4.0), the TXD2 (P4.2) and RXD2 (P4.0) of the MCU are connected to the VIA and VIB pins of the digital isolator, and then the VOA and VOB pins of the digital isolator are connected to the RO and DO pins of the 485 chip. By digitally isolating the 485 transmission and reception, the interference in the signal transmission process can be effectively reduced, and the stability and reliability of the communication can be guaranteed.

[0072] In summary, the utility model comprehensive detection unit can monitor system voltage, current, temperature and other parameters in real time, and improve the reliability and safety of system operation. The utility model comprehensive detection unit can automatically manage two AC lines, detect six-phase voltage, and detect over-voltage, under-voltage, lack of phase and other alarms of the two AC lines in real time. The AC voltage detection module of the utility model is composed of a high-precision isolation sensor, a high-precision metering chip U4, and a plurality of capacitors and resistors to form an acquisition circuit. By collecting two three-phase AC voltages and one DC to the AC voltage of the earth, the isolated and collected signals are respectively sent to each pin of the metering chip U4 through the current limiting resistor and the filter capacitor, and then converted into a digital signal by the metering chip U4 and transmitted to the MCU. The AC voltage is read through the MCU processing and the frequency and power factor of the AC voltage can also be calculated.

[0073] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An integrated detection unit, including an MCU, characterized in that: Also includes: An AC voltage detection module electrically connected to the MCU and used to collect an AC voltage from one DC to the ground and at least one three-phase AC voltage; A DC voltage detection module electrically connected to the MCU and used for sampling one insulation voltage and at least one DC voltage; A DC current detection module electrically connected to the MCU; A temperature detection module electrically connected to the MCU.

2. The integrated detection unit according to claim 1, characterized in that: The MCU is a single chip microcomputer with flash memory and RAM, and the single chip microcomputer supports ISP programming and IAP programming.

3. The integrated detection unit according to claim 1, characterized in that: The AC voltage detection module includes a metering chip U4 and seven groups of isolated sensor circuits electrically connected to the metering chip U4. Among the seven groups of isolated sensor circuits, one group of isolated sensor circuits is for DC to earth AC power collection, and the other six groups are divided into two-way collection circuits, and the two-way collection circuits collect two three-phase voltages respectively.

4. The integrated detection unit according to claim 3, characterized in that: Any set of isolated sensing circuits includes a sensor TP, seven resistors and two first capacitors; In any group of isolated sensor circuits, the first end of the primary coil of the sensor TP is connected to a series circuit consisting of three first resistors, two second resistors connected in series are connected between the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP, the first end of the secondary coil of the sensor TP and the second end of the secondary coil of the sensor TP are both connected to a third resistor, the other ends of the two third resistors are both connected to a first capacitor, and the other ends of the first capacitors are connected to each other and grounded; In the two-way three-phase voltage acquisition circuit, the other end of the series circuit is connected to the live wire, and the second end of the primary coil of the sensor TP is connected to the neutral wire; In the ground AC power collection circuit, the other end of the series circuit is connected to the PE ground, and the second end of the primary coil of the sensor TP is connected to the PE2 ground.

5. The integrated detection unit according to claim 4, characterized in that: In each isolation sensor circuit, an isolated and collected signal is generated between the third resistor and the first capacitor connected to the third resistor, and each signal is connected one-to-one to the signal receiving pin of the metering chip U4 and a digital signal is generated by the metering chip U4; The 38-pin DOUT of the metering chip U4, the 37-pin DIN of the metering chip U4, the 36-pin SCLK of the metering chip U4, and the 35-pin CS of the metering chip U4 are connected one-to-one to the signal receiving pins of the MCU.

6. The integrated detection unit according to claim 1, characterized in that: The DC voltage detection module includes five DC voltage sampling circuits and one insulation voltage sampling circuit; The DC voltage sampling circuit includes a first step-down circuit and a first RC current limiting filter circuit connected to the first step-down circuit, and the first RC current limiting filter circuit is connected to the ADC of the MCU; The insulation voltage sampling circuit includes a second step-down circuit and a second RC current limiting filter circuit connected to the second step-down circuit.

7. The integrated detection unit according to claim 1, characterized in that: The DC current detection module includes an operational amplifier U5A, an operational amplifier U5B, an operational amplifier U6B, a plurality of resistors, and a plurality of capacitors; The in-phase input terminal of the operational amplifier U5A is connected to a resistor R132, and the resistor R132 is connected to a temperature detection module; The inverting input terminal of the operational amplifier U5A is connected to the first end of the resistor R133, the first end of the resistor R131, and the output terminal of the operational amplifier U5A; The non-inverting input terminal of the operational amplifier U5B is connected to the first end of the resistor R134 and the first end of a first RC circuit, the second end of the resistor R134 is connected to the MCU, the second end of the first RC circuit is grounded, and the first RC circuit includes a capacitor C56 and a resistor R136 connected in parallel; The inverting input terminal of the operational amplifier U5B is connected to the output terminal of the operational amplifier U5B and the first end of the resistor R135, the second end of the resistor R135 is respectively connected to the second end of the resistor R131 and the first end of the capacitor C55, and the second end of the capacitor C55 is grounded; The non-inverting input terminal of the operational amplifier U6B is connected to the first end of the resistor R137 and the first end of the second RC circuit, the second end of the resistor R137 is connected to the MCU, the second end of the second RC circuit is grounded, and the second RC circuit includes a resistor R139 and a capacitor C58 connected in parallel; The inverting input terminal of the operational amplifier U6B is connected to the output terminal of the operational amplifier U6B, the output terminal of the operational amplifier U6B is connected to the first end of the resistor R138, the second end of the resistor R138 is connected to the second end of the resistor R133 and the first end of the capacitor C57, and the second end of the capacitor C57 is grounded.

Images