Low-power-consumption intelligent integrated fault isolation device

Abstract

The utility model relates to a low-power-consumption intelligent integrated fault isolation device, which comprises a deep fusion solid-sealed polar pole circuit breaker body and a low-power-consumption intelligent FTU, the deep fusion solid-sealed polar pole circuit breaker body comprises a mechanism box and a deep fusion solid-sealed polar pole, and the deep fusion solid-sealed polar pole is internally provided with a high-voltage capacitance energy taking device, a current sensor and a voltage sensor; the low-power-consumption intelligent FTU comprises a low-power-consumption microprocessor, a power supply module, an analog-to-digital conversion circuit, a voltage and current acquisition circuit, an isolation circuit, a drive circuit, a line loss module circuit and a GPRS module circuit. The device is small in size, light in weight, low in power consumption and capable of timely and accurately isolating power distribution network line faults, avoiding large-range power failure and reducing economic losses, and the power taking device is integrally designed.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breaker feeder terminals, in particular to a low-power consumption intelligent integrated fault isolation device. Background Art

[0002] At present, with the gradual advancement of the primary and secondary integration of distribution network equipment, new switchgear such as integrated fault isolation devices are gradually being promoted and applied.

[0003] Traditional fault isolation devices usually consist of three parts: the circuit breaker body, the FTU measurement and control terminal, and the electromagnetic voltage transformer. They are independent of each other and installed separately, and the three are connected with aviation plugs. The electromagnetic voltage transformer is used to draw energy from the busbar. Therefore, the equipment cost of traditional fault isolation devices is high, and there is a risk of wiring errors during on-site construction.

[0004] A known integrated fault isolation device adopts a double-sided power supply mode by installing high-voltage capacitor energy supply devices at both ends of the base of the measurement and control device, so that the integrated fault isolation device and the energy supply device are integrated into one design, reducing the risk of wiring errors in on-site construction. However, the current maximum capacitor power supply power of products from relevant circuit breaker manufacturers is about 25W, and the minimum is about 6W, which cannot meet the overall working power consumption of the circuit breaker body and the measurement and control terminal. Therefore, a solar energy power supply device is added as a supplement. The equipment cost is also high and the solar energy supply is unstable. Summary of the invention

[0005] The purpose of the utility model is to solve the problems existing in the above-mentioned prior art and provide a low-power consumption intelligent integrated fault isolation device.

[0006] The specific scheme of the utility model is: a low-power intelligent integrated fault isolation device, including a deep fusion sealed pole circuit breaker body and a low-power intelligent FTU, the low-power intelligent FTU is integrated and installed on the deep fusion sealed pole circuit breaker body, the deep fusion sealed pole circuit breaker body includes a mechanism box and a deep fusion sealed pole, and a high-voltage capacitor energy acquisition device, a current sensor and a voltage sensor are arranged in the deep fusion sealed pole; the low-power intelligent FTU includes a low-power microprocessor, a power supply module, an analog-to-digital conversion circuit, a voltage and current acquisition circuit, an isolation circuit, a drive circuit, a line loss module circuit, and a GPRS module circuit, the power supply module power-taking end is connected to the high-voltage capacitor energy acquisition device, the power supply end of the power supply module is connected to the microprocessor to power the microprocessor; the input end of the voltage and current acquisition circuit is connected to the current sensor and the voltage sensor, the output end is connected to the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is connected to the microprocessor; the output end of the line loss module circuit is connected to the microprocessor, the microprocessor is connected to the isolation circuit, the isolation circuit is connected to the drive circuit, and the drive circuit is connected to the switch of the circuit breaker.

[0007] Furthermore, the current sensor includes a three-phase current sensor and a zero-sequence current sensor, and the voltage sensor includes a three-phase voltage sensor and a zero-sequence voltage sensor.

[0008] Furthermore, the low-power intelligent FTU also includes a backup battery, which is connected to the power supply module.

[0009] Furthermore, the power supply module is provided with a backup battery discharge management circuit and a backup battery charge management circuit.

[0010] Furthermore, the backup battery discharge management circuit is composed of a drive circuit, a battery shutdown voltage detection circuit and an output circuit. The drive circuit includes a chip, an energy storage capacitor, a voltage regulator, and a resistor; the battery shutdown voltage detection circuit includes a chip, a resistor, and a capacitor; the output circuit includes a chip, a switch MOS tube, a drive transistor, and a resistor.

[0011] Furthermore, the backup battery charging management circuit is composed of a resistor, a capacitor, a driving transistor, a switching MOS tube, and a protection diode; the switching effect of the driving transistor is utilized to drive the driving transistor to conduct through the voltage across the resistor, thereby indirectly driving the switching MOS tube to be turned on and off to charge the backup battery.

[0012] The utility model has the following beneficial effects: 1. Small size, light weight, integrated design of power taking device, providing working power for device components, not affected by weather and load current changes, stable and reliable; 2. No secondary connection is required for on-site construction, eliminating the risk of wiring errors, construction can be completed with one lifting, low construction intensity, short cycle, and reduced power outage time; 3. Distribution network line faults can be isolated in a timely and accurate manner to avoid large-scale power outages and reduce economic losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is the main topological circuit diagram of the utility model;

[0014] Figure 2 This is a schematic diagram of the voltage and current signal acquisition circuit of the utility model;

[0015] Figure 3 This is a schematic diagram of the isolation circuit of the utility model;

[0016] Figure 4 This is a schematic diagram of the backup battery discharge management circuit of the utility model;

[0017] Figure 5 This is a schematic diagram of the backup battery charging management circuit of the utility model;

[0018] Figure 6 This is a schematic diagram of the analog-to-digital conversion circuit of the utility model;

[0019] Figure 7 This is a schematic diagram of the drive circuit of the utility model. DETAILED DESCRIPTION

[0020] See also Figure 1 The low-power intelligent integrated fault isolation device of this embodiment includes a deep fusion sealed pole circuit breaker body and a low-power intelligent FTU. The low-power intelligent FTU is integrated and installed on the deep fusion sealed pole circuit breaker body. The deep fusion sealed pole circuit breaker body includes a mechanism box and a deep fusion sealed pole. A high-voltage capacitor energy acquisition device, a current sensor and a voltage sensor are arranged in the deep fusion sealed pole; the low-power intelligent FTU includes a low-power microprocessor, a power supply module, an analog-to-digital conversion circuit, a voltage and current acquisition circuit, an isolation circuit, a drive circuit, a line loss module circuit, and a GPRS module circuit. The power supply module power-taking end is connected to the high-voltage capacitor energy acquisition device, and the power supply end of the power supply module is connected to the microprocessor to power the microprocessor; the input end of the voltage and current acquisition circuit is connected to the current sensor and the voltage sensor, and the output end is connected to the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is connected to the microprocessor; the output end of the line loss module circuit is connected to the microprocessor, the microprocessor is connected to the isolation circuit, the isolation circuit is connected to the drive circuit, and the drive circuit is connected to the switch of the circuit breaker.

[0021] Furthermore, the current sensor includes a three-phase current sensor and a zero-sequence current sensor, and the voltage sensor includes a three-phase voltage sensor and a zero-sequence voltage sensor.

[0022] Furthermore, the low-power intelligent FTU also includes a backup battery, which is connected to the power supply module.

[0023] Furthermore, the power supply module is provided with a backup battery discharge management circuit and a backup battery charge management circuit.

[0024] See also Figure 2 This is the voltage and current signal acquisition circuit described in this embodiment, in which U20 uses ADI's low-cost, high-precision instrument amplifier, which only requires an external resistor to set the gain, and the gain range is 1 to 10000. It has the characteristics of low noise and low power consumption, and the maximum power supply current is 1.3mA. RZ1 is a gas discharge tube to prevent surge interference and ensure the true stability of signal acquisition. Z1 is a TVS transient suppression diode to prevent electrostatic discharge interference and ensure the stability of signal acquisition. At the same time, the circuit uses an RC filter circuit, which can effectively filter out high-frequency interference and improve the sampling accuracy of the device.

[0025] See also Figure 3The signal isolation circuit of this embodiment uses a photocoupler to isolate and transmit signals, ensuring signal consistency and effectively protecting the subsequent circuit from interference and damage by external interference signals, improving the reliability of the device and preventing false alarms and malfunctions of the device signals. In addition, the driving circuit of the photocoupler is small and has low power consumption, which also reduces the overall power consumption of the device.

[0026] See also Figure 4 The backup battery discharge management circuit includes a chip U35, energy storage capacitors C143, C144, a voltage regulator D9, resistors R139, R140 to form a driving circuit of a battery voltage detection chip U35; a chip U35, resistors R147, R148, R149, and a capacitor C145 to form a battery shutdown voltage detection circuit; a chip U35, a switch MOS tube Q5, a driving transistor Q6, resistors R141, R142, and R144 to form a battery output circuit. Among them, the chip U35 adopts CN301, which has the characteristics of extremely low power consumption.

[0027] When KEY+ and KEY- are closed, the voltage regulator D9 increases the constant working voltage for the chip U35. When the chip U35 detects that the battery voltage is greater than the preset shutdown voltage, the switch MOS tube Q5 is turned on and the battery output voltage is turned on. Otherwise, the switch MOS tube Q5 is turned off and the battery output voltage is turned off. This circuit can monitor the battery voltage in real time. If the battery voltage is lower than the preset shutdown voltage, the battery output is immediately turned off, effectively avoiding the problem of excessive battery discharge.

[0028] See also Figure 5 The backup battery charging management circuit is composed of resistors R1, R2, R3, R4, R5, capacitors C1, C2, driving transistor Q1, switch MOS tube Q2, and protection diode D1. The circuit uses the switching effect of the driving transistor Q1 to drive Q1 to turn on through the voltage across the resistor R3, and indirectly drives Q2 to turn on and off to charge the backup battery. The battery charging current is calculated by the resistance value of R3, I=0.5 / R3.

[0029] This circuit is simple and can effectively limit the battery charging current to 150mA (the battery charging power can be adjusted according to the output power of the high-voltage energy-taking capacitor), thus avoiding the problem of the output voltage of the energy-taking device being lowered due to excessive battery charging power. At the same time, the loss of the circuit itself is also extremely small, reducing the overall power consumption of the device.

[0030] See also Figure 6The analog-to-digital conversion circuit adopts ADI's integrated AD chip AD7606, which has an eight-channel 16-bit, synchronous sampling, analog-to-digital data acquisition system (DAS). The device includes analog input clamp protection, second-order anti-aliasing analog filter, sample-and-hold amplifier, 16-bit charge redistribution successive approximation analog-to-digital converter (ADC), flexible digital filter, 2.5V reference voltage source and reference buffer, as well as high-speed serial and parallel interfaces. In addition, the chip is powered by a single 5V power supply and can adapt to ±10V and ±5V true bipolar input signals.

[0031] All channels can be sampled at a throughput rate of up to 200 kSPS. The input clamp protection circuit can withstand voltages up to ±16.5 V. Regardless of the sampling frequency used, the AD7606 has an analog input impedance of 1 MΩ. Due to the single-power supply, on-chip filtering, and high input impedance, there is no need to drive an operational amplifier and an external bipolar power supply. At the same time, it has low power consumption characteristics, consuming 100mW in low-power mode and only 25mW in standby mode, which greatly reduces the power consumption of the device.

[0032] See also Figure 7 The switch drive circuit uses a photocoupler as a signal isolation driver to effectively eliminate the influence of interference signals on the device and avoid power outages caused by malfunction of the device. At the same time, the relay that drives the device switch uses an Omron relay, which has high sensitivity and high capacity (can carry 16A load), and the number of coil closing operations is not less than 100,000 times, ensuring the service life of the device.

[0033] Furthermore, the GPRS module described in this embodiment adopts an integrated wireless IC module to meet the communication requirements of DL / T634.5101-2002 and DL / T634.5104-2009. The interface between the wireless communication module and the SIM card meets the requirements of GSM11.11, and the data exchange with the SIM card meets the requirements of GSM11.14. It is compatible with 2G / 3G / 4G standards, supports port data monitoring function, and has the function of automatic reconnection when the network is disconnected. At the same time, it also supports local maintenance function, which can be debugged, parameter set, status query and software upgrade operation through the local maintenance interface. In addition, the average working power consumption of the wireless communication module is less than 0.4W, and the instantaneous maximum power consumption during startup and communication is not more than 5W.

[0034] Furthermore, the integrated line loss module circuit described in this embodiment uses TVS transient suppression diodes, gas discharge tubes and other protective devices to protect the module from static electricity and surge interference. The module uses a micro MCU-V8530 processor. The MCU-V8530 integrates the Cortex-M0 core, 256KB FLASH, 32KB SRAM, UART / SPI / I2C interface, LCD, WDT and RTC, supports multiple low-power working modes, and supports independent power supply of RTC power supply. In addition, the module uses the IC chip V9203 for metering and collection, has high metering accuracy, provides various measurement data, supports full-wave active power segment ratio difference correction (three segments) and secondary compensation (offset correction), supports full-wave / fundamental reactive power and fundamental active power ratio difference correction and secondary compensation (offset correction), and also supports deep sleep mode. After the chip power is completely turned off, the typical working current of the chip is 0.2μA, which minimizes power loss.

[0035] In this embodiment, the low-power terminal core unit design adopts a low-power MCU, the signal conditioning sampling uses an ultra-low-power op amp, the DC power supply uses an efficient 24VDC / 5VDC, 5VDC / ±5VDC, 5VDC / 3.3VDC, and the module circuit power supply uses a controlled power supply to control and reduce power consumption. The low-power power supply module design is the core module of the FTU system power supply, which is used to manage and distribute various input voltages, output voltages to power various modules of the system, and charge batteries to achieve charge and discharge management of the device battery.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the specific implementation modes of the present invention can still be modified or replaced by equivalents, and any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. The low-power intelligent integrated fault isolation device includes a deep fusion solid-sealed pole circuit breaker body and a low-power intelligent FTU. The low-power intelligent FTU is integrated and installed on the deep fusion solid-sealed pole circuit breaker body. The characteristics are: The deep fusion sealed pole circuit breaker body includes a mechanism box and a deep fusion sealed pole, and a high-voltage capacitor energy acquisition device, a current sensor and a voltage sensor are arranged in the deep fusion sealed pole; the low-power intelligent FTU includes a low-power microprocessor, a power supply module, an analog-to-digital conversion circuit, a voltage and current acquisition circuit, an isolation circuit, a drive circuit, a line loss module circuit, and a GPRS module circuit. The power supply module power supply end is connected to the high-voltage capacitor energy acquisition device, and the power supply end of the power supply module is connected to the microprocessor to power the microprocessor; the input end of the voltage and current acquisition circuit is connected to the current sensor and the voltage sensor, and the output end is connected to the analog-to-digital conversion circuit, and the output end of the analog-to-digital conversion circuit is connected to the microprocessor; the output end of the line loss module circuit is connected to the microprocessor, the microprocessor is connected to the isolation circuit, the isolation circuit is connected to the drive circuit, and the drive circuit is connected to the switch of the circuit breaker.

2. The low-power intelligent integrated fault isolation device according to claim 1 is characterized in that: The current sensor includes a three-phase current sensor and a zero-sequence current sensor, and the voltage sensor includes a three-phase voltage sensor and a zero-sequence voltage sensor.

3. The low-power intelligent integrated fault isolation device according to claim 1 is characterized in that: The low-power intelligent FTU also includes a backup battery, which is connected to the power supply module.

4. The low-power intelligent integrated fault isolation device according to claim 3 is characterized in that: The power supply module is provided with a backup battery discharge management circuit and a backup battery charge management circuit.

5. The low-power intelligent integrated fault isolation device according to claim 4 is characterized in that: The backup battery discharge management circuit is composed of a drive circuit, a battery shutdown voltage detection circuit and an output circuit. The drive circuit includes a chip, an energy storage capacitor, a voltage regulator tube and a resistor; the battery shutdown voltage detection circuit includes a chip, a resistor and a capacitor; the output circuit includes a chip, a switch MOS tube, a drive transistor and a resistor.

6. The low-power intelligent integrated fault isolation device according to claim 4 is characterized in that: The backup battery charging management circuit is composed of a resistor, a capacitor, a driving transistor, a switch MOS tube, and a protection diode; the switching effect of the driving transistor is utilized to drive the driving transistor to conduct through the voltage across the resistor, thereby indirectly driving the switch MOS tube to be turned on and off to charge the backup battery.

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