Boost Circuit of Elevator Emergency Rescue Device

Abstract

The present invention discloses a boost circuit for an elevator emergency rescue device. Based on the existing boost circuit, a transformer winding adjustment circuit is provided to shorten the access length of the secondary winding of the boost transformer after receiving a control command, so as to reduce the output voltage of the boost circuit; and a voltage dividing resistor short-circuiting circuit is provided to short-circuit at least one voltage dividing resistor in the output voltage sampling feedback circuit after receiving a control command, so as to offset the voltage dividing ratio corresponding to the shortened secondary winding of the boost transformer, ensuring that the output efficiency of the boost circuit remains basically unchanged. Compared with the prior art, the boost circuit of the elevator emergency rescue device of the present invention can change the output voltage within a large range without affecting the output efficiency of the entire boost circuit.

Description

Technical Field

[0001] The present invention relates to an elevator emergency rescue device (ARD), in particular to a boost circuit of the elevator emergency rescue device. Background Art

[0002] With the progress of society, buildings in cities tend to be built higher and higher, and elevators are more and more widely used in high-rise residential or office buildings.

[0003] When an operating elevator suddenly encounters a power supply system failure (such as power outage, line failure, etc.), its car will be stuck in the hoistway, and in many cases, it is stuck between floors. The traditional treatment method is to wait for professionals to arrive at the scene for rescue. However, staying in the narrow elevator car for a long time waiting for rescue will have an adverse impact on the physical and mental health of the trapped people. Improper self-rescue behaviors made by the trapped people due to panic will also increase the possibility of accidents.

[0004] As an effective means to ensure the safety of passengers when the elevator power supply system fails, the elevator emergency rescue device (ARD) came into being. The elevator emergency rescue device is an emergency rescue device for trapped elevators. It generally includes an isolation contactor, an MCU control module, a mains monitoring module, a charging module, a battery, a DC-DC boost circuit, and a DC-AC inverter module. When working, when the mains monitoring module monitors that the mains is normal, the isolation contactor is closed, and at the same time, the charging module charges the battery. At this time, the MCU monitors the mains status and the battery charging situation and indicates the corresponding status. When the mains suddenly fails or the power supply line fails and the elevator stops in the hoistway, the MCU control module receives a power abnormality signal sent by the mains monitoring module, outputs a control signal to control the isolation contactor to release, disconnects the mains power supply line, and starts counting down. After reaching the set interval time, the battery of the elevator emergency rescue device is used to supply power to the elevator. The MCU control module outputs a control signal to start the DC-DC boost circuit. After the output of the battery is boosted by the DC-DC boost circuit, it is then inverted by the DC-AC inverter module to output alternating current to supply power to the elevator. At the same time, the MCU control module also sends a trigger signal to the elevator control system. After receiving this trigger signal, the elevator control system starts its own rescue operation program to make the elevator run to the flat layer position in the energy-saving direction to open the door and release the trapped passengers, so that the trapped people can be quickly rescued from danger.

[0005] The existing elevator emergency rescue device, its boost circuit is as Figure 1As shown in the figure, it includes a PWM module, a power amplification circuit, a boost transformer T1, a rectification module, a filtering module, and an output voltage sampling and feedback circuit. The PWM module, the power amplification circuit, the boost transformer T1, the rectification module, and the filtering module are connected in sequence. The input end of the output voltage sampling and feedback circuit is connected to the output end of the filtering module, and the output end is connected to the feedback input end of the PWM module. During operation, a pulse width modulation signal is generated by the PWM module, amplified by the power transistors Q1 and Q2 of the power amplification circuit, boosted by the boost transformer T1, rectified by the rectification module, and filtered by the filtering module in sequence to output a DC voltage. At the same time, the output voltage sampling and feedback circuit is sent to the sampling and feedback module through the adjustable resistor RW1, the voltage dividing resistor R2, and the voltage dividing resistor R3, and then fed back to the PWM module as a feedback signal to adjust the duty cycle of the PWM signal, so as to stabilize the output DC voltage within a certain range. For this boost circuit, the output voltage is determined by the duty cycle of the PWM signal. However, since the winding of the boost transformer T1 is fixed, changing the duty cycle of the PWM signal can change the output voltage within a certain range, but the adjustment range is limited. If the adjustment range is too large, the efficiency of the entire boost circuit will drop significantly.

[0006] To solve this problem, the applicant conducted in-depth research on the boost circuit, and thus this case came into being. Summary of the Invention

[0007] The object of the present invention is to provide a boost circuit for an elevator emergency rescue device, which can change the output voltage within a large range without affecting the efficiency of the entire boost circuit.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] The boost circuit of the elevator emergency rescue device includes a PWM module, a power amplification circuit, a boost transformer, a rectification module, a filtering module, and an output voltage sampling and feedback circuit. The PWM module, the power amplification circuit, the boost transformer, the rectification module, and the filtering module are connected in sequence. The input end of the output voltage sampling and feedback circuit is connected to the output end of the filtering module, and the output end is connected to the feedback input end of the PWM module;

[0010] It further includes a transformer winding adjustment circuit, which is used to shorten the access length of the secondary winding of the boost transformer after receiving a control command to reduce the output voltage of the boost circuit;

[0011] It further includes a voltage-dividing resistor short-circuiting circuit, which is used to short-circuit at least one voltage-dividing resistor in the output voltage sampling and feedback circuit after receiving a control instruction, so as to offset the voltage-dividing ratio corresponding to the shortened secondary winding of the step-up transformer, and ensure that the output efficiency of the step-up circuit remains basically unchanged.

[0012] The transformer winding adjustment circuit includes a conversion relay K1, a triode Q3 and a resistor R1. The secondary winding of the step-up transformer has a first end, a second end, and an adjustment end located between the first end and the second end. One end of the resistor R1 is connected to the control instruction input terminal, the other end of the resistor R1 is connected to the base of the triode Q3, the emitter of the triode Q3 is grounded, the collector of the triode Q3 is connected to one end of the coil of the conversion relay K1, the other end of the coil of the conversion relay K1 is connected to the working power supply, the common terminal of the conversion relay K1 is connected to the input terminal of the rectification module, and the normally closed contact and the normally open contact of the conversion relay K1 are respectively connected to the first end of the secondary winding of the step-up transformer and the adjustment end of the secondary winding of the step-up transformer.

[0013] The voltage-dividing resistor short-circuiting circuit includes an optocoupler U1 and a resistor R4. One end of the resistor R4 is connected to the control instruction input terminal, the other end of the resistor R4 is connected to the anode of the infrared emitting tube of the optocoupler U1, the cathode of the infrared emitting tube of the optocoupler U1 is grounded, and the collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of a certain voltage-dividing resistor in the output voltage sampling and feedback circuit or the head and tail ends of multiple serially-connected voltage-dividing resistors in the output voltage sampling and feedback circuit.

[0014] The output voltage sampling and feedback circuit includes a variable resistor RW1, a voltage-dividing resistor R2, a voltage-dividing resistor R3 and a sampling and feedback module. The variable resistor RW1, the voltage-dividing resistor R2 and the voltage-dividing resistor R3 are sequentially connected in series between the positive output terminal of the filtering module and the positive input terminal of the sampling and feedback module. The negative input terminal of the sampling and feedback module is connected to the negative output terminal of the filtering module, and the collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of the voltage-dividing resistor R3.

[0015] The control instruction input terminal is connected to a manual control signal or an automatic control signal.

[0016] The manual control signal is switched on and off through a manual switch.

[0017] The automatic control signal comes from the MCU control module of the elevator emergency rescue device or other control circuits.

[0018] After adopting the above solution, the boost circuit of the elevator emergency rescue device of the present invention sets a transformer winding adjustment circuit to shorten the access length of the secondary winding of the boost transformer after receiving a control instruction, so as to reduce the output voltage of the boost circuit; and sets a voltage dividing resistor short-circuit circuit to short-circuit at least one voltage dividing resistor in the output voltage sampling feedback circuit after receiving a control instruction, so as to offset the voltage dividing ratio corresponding to the shortened secondary winding of the boost transformer, and ensure that the output efficiency of the boost circuit remains basically unchanged. Compared with the prior art, the boost circuit of the elevator emergency rescue device of the present invention can change the output voltage within a large range without affecting the output efficiency of the entire boost circuit. Description of the Drawings

[0019] Figure 1 is the circuit schematic diagram of the boost circuit of the existing elevator emergency rescue device;

[0020] Figure 2 is the circuit schematic diagram of the boost circuit of the elevator emergency rescue device of the present invention. Detailed Embodiments

[0021] The boost circuit of the elevator emergency rescue device of the present invention, as Figure 2 shown, includes a PWM module, a power amplification circuit, a boost transformer T1, a rectification module, a filtering module, and an output voltage sampling feedback circuit. The PWM module, the power amplification circuit, the boost transformer T1, the rectification module, and the filtering module are connected in sequence, and the input end of the output voltage sampling feedback circuit is connected to the output end of the filtering module, and the output end is connected to the feedback input end of the PWM module.

[0022] Specifically:

[0023] The power amplification circuit includes a power transistor Q1 and a power transistor Q2. The gates of the power transistor Q1 and the power transistor Q2 are respectively connected to the corresponding output ends of the PWM module. The sources of the power transistor Q1 and the power transistor Q2 are both connected to the negative pole of the storage battery. The drains of the power transistor Q1 and the power transistor Q2 are respectively connected to both ends of the primary coil of the boost transformer T1.

[0024] The output voltage sampling feedback circuit includes a variable resistor RW1, a voltage dividing resistor R2, a voltage dividing resistor R3, and a sampling feedback module. The variable resistor RW1, the voltage dividing resistor R2, and the voltage dividing resistor R3 are connected in series between the positive output terminal of the filtering module and the positive input terminal of the sampling feedback module. The negative input terminal of the sampling feedback module is connected to the negative output terminal of the filtering module, and the output terminal of the sampling feedback module is connected to the feedback input terminal of the PWM module.

[0025] The main innovation of the present invention is to provide a transformer winding adjustment circuit and a voltage-dividing resistor short-circuiting circuit. The transformer winding adjustment circuit is used to shorten the access length of the secondary winding of the step-up transformer T1 after receiving a control instruction, so as to reduce the output voltage of the step-up circuit; the voltage-dividing resistor short-circuiting circuit is used to short-circuit at least one voltage-dividing resistor in the output voltage sampling feedback circuit after receiving a control instruction, so as to offset the voltage-dividing ratio corresponding to the shortened secondary winding of the step-up transformer T1, and ensure that the output efficiency of the step-up circuit remains basically unchanged.

[0026] Specifically:

[0027] The transformer winding adjustment circuit includes a conversion relay K1, a triode Q3 and a resistor R1. The secondary winding of the step-up transformer T1 has a first end, a second end, and an adjustment end located between the first end and the second end. One end of the resistor R1 is connected to the control instruction input terminal A, the other end of the resistor R1 is connected to the base of the triode Q3, the emitter of the triode Q3 is grounded, the collector of the triode Q3 is connected to one end of the coil of the conversion relay K1, the other end of the coil of the conversion relay K1 is connected to the working power supply, the common terminal of the conversion relay K1 is connected to the input terminal of the rectification module, and the normally closed contact and the normally open contact of the conversion relay K1 are respectively connected to the first end of the secondary winding of the step-up transformer T1 and the adjustment end of the secondary winding of the step-up transformer T1.

[0028] The voltage-dividing resistor short-circuiting circuit includes an optocoupler U1 and a resistor R4. One end of the resistor R4 is connected to the control instruction input terminal A, the other end of the resistor R4 is connected to the anode of the infrared emitting tube of the optocoupler U1, the cathode of the infrared emitting tube of the optocoupler U1 is grounded, and the collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of a certain voltage-dividing resistor in the output voltage sampling feedback circuit or the head and tail ends of multiple serially connected voltage-dividing resistors in the output voltage sampling feedback circuit. In this embodiment, the collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of the voltage-dividing resistor R3.

[0029] After adopting the above scheme, the step-up circuit of the elevator emergency rescue device of the present invention, by setting a transformer winding adjustment circuit to shorten the access length of the secondary winding of the step-up transformer after receiving a control instruction, so as to reduce the output voltage of the step-up circuit; and by setting a voltage-dividing resistor short-circuiting circuit to short-circuit at least one voltage-dividing resistor in the output voltage sampling feedback circuit after receiving a control instruction, so as to offset the voltage-dividing ratio corresponding to the shortened secondary winding of the step-up transformer, and ensure that the output efficiency of the step-up circuit remains basically unchanged. Compared with the prior art, the step-up circuit of the elevator emergency rescue device of the present invention can change the output voltage within a large range without affecting the output efficiency of the entire step-up circuit.

[0030] The working principle of the boost circuit of the elevator emergency rescue device of the present invention is as follows:

[0031] The pulse width modulation signal output by the PWM module is amplified by power tubes Q1 and Q2, boosted by boost transformer T1, and then output as a DC voltage after passing through the rectification module and the filtering module. At the same time, it is divided by adjustable resistor RW1, voltage dividing resistors R2 and R3, sent to the sampling feedback module, and then fed back to the PWM module as a feedback signal to adjust the duty cycle of the pulse width modulation signal, so as to stabilize the DC voltage output by the boost circuit within a certain range.

[0032] When it is necessary to reduce the output voltage, a high-level signal is manually or automatically given to the control command input terminal A. Since resistors R1 and R4 are both connected to the control command input terminal A, at this time, triode Q3 and optocoupler U1 are simultaneously turned on, and the coil of conversion relay K1 is energized and attracted. The normally closed contact of conversion relay K1 is disconnected, and the normally open contact is closed. That is, the connection between the common terminal of conversion relay K1 and the first end of the secondary winding of boost transformer T1 is disconnected, and the common terminal of conversion relay K1 is switched to connect to the adjustment end of the secondary winding of boost transformer T1. At this time, a part of the winding of boost transformer T1 (the part between the first end and the adjustment end) does not enter the circuit, thereby reducing the output voltage of the boost circuit. At the same time, optocoupler U1 shorts voltage dividing resistor R3, and voltage dividing resistor R3 does not participate in the voltage dividing feedback circuit. By setting reasonable circuit parameters, the voltage division ratio of voltage dividing resistor R3 is basically equal to the voltage ratio of the part of the winding of boost transformer T1 cut off after relay K1 is attracted. Therefore, although the output voltage of the boost circuit is reduced, the output efficiency remains basically unchanged.

[0033] In the present invention, the control command input terminal A can be connected to a manual control signal or an automatic control signal, as long as the control command input terminal A is at a high level when switching is required. Specifically, the manual control signal can be switched on and off through a manual switch. The automatic control signal can come from the MCU control module of the elevator emergency rescue device or other control circuits.

[0034] In the present invention, the pulse width modulation signal can be generated by the PWM module or by an MCU module. In this embodiment, the PWM module uses the PWM pulse width control chip SG3525 to generate the pulse width modulation signal.

[0035] The above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, based on the above description, other changes or variations in different structural forms can be made. It is not necessary and impossible to enumerate all implementation manners here. And these obvious changes or variations derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. The boost circuit of an elevator emergency rescue device includes a PWM module, a power amplification circuit, a boost transformer, a rectification module, a filtering module, and an output voltage sampling and feedback circuit. The PWM module, the power amplification circuit, the boost transformer, the rectification module, and the filtering module are connected in sequence. The input end of the output voltage sampling and feedback circuit is connected to the output end of the filtering module, and the output end is connected to the feedback input end of the PWM module; It is characterized in that: It further includes a transformer winding adjustment circuit, which is used to shorten the access length of the secondary winding of the boost transformer after receiving a control instruction to reduce the output voltage of the boost circuit; It further includes a voltage dividing resistor short-circuiting circuit, which is used to short-circuit at least one voltage dividing resistor in the output voltage sampling and feedback circuit after receiving a control instruction to offset the voltage dividing ratio corresponding to the shortened secondary winding of the boost transformer and ensure that the output efficiency of the boost circuit remains basically unchanged.

2. The boost circuit of the elevator emergency rescue device according to claim 1, It is characterized in that: The transformer winding adjustment circuit includes a conversion relay K1, a triode Q3, and a resistor R1. The secondary winding of the boost transformer has a first end, a second end, and an adjustment end located between the first end and the second end. One end of the resistor R1 is connected to the control instruction input end, the other end of the resistor R1 is connected to the base of the triode Q3, the emitter of the triode Q3 is grounded, the collector of the triode Q3 is connected to one end of the coil of the conversion relay K1, the other end of the coil of the conversion relay K1 is connected to the working power supply, the common end of the conversion relay K1 is connected to the input end of the rectification module, and the normally closed contact and the normally open contact of the conversion relay K1 are respectively connected to the first end of the secondary winding of the boost transformer and the adjustment end of the secondary winding of the boost transformer.

3. The boost circuit of the elevator emergency rescue device according to claim 1, It is characterized in that: The voltage dividing resistor short-circuiting circuit includes an optocoupler U1 and a resistor R4. One end of the resistor R4 is connected to the control instruction input end, the other end of the resistor R4 is connected to the anode of the infrared emitting diode of the optocoupler U1, the cathode of the infrared emitting diode of the optocoupler U1 is grounded, and the collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of a certain voltage dividing resistor in the output voltage sampling and feedback circuit or the head and tail ends of multiple serially connected voltage dividing resistors in the output voltage sampling and feedback circuit.

4. The boost circuit of the elevator emergency rescue device according to claim 3, It is characterized in that: The output voltage sampling and feedback circuit includes a variable resistor RW1, a voltage dividing resistor R2, a voltage dividing resistor R3, and a sampling and feedback module. The variable resistor RW1, the voltage dividing resistor R2, and the voltage dividing resistor R3 are sequentially connected in series between the positive output terminal of the filtering module and the positive input terminal of the sampling and feedback module. The negative input terminal of the sampling and feedback module is connected to the negative output terminal of the filtering module. The collector and emitter of the light-receiving triode of the optocoupler U1 are respectively connected to both ends of the voltage dividing resistor R3.

5. The boost circuit of the elevator emergency rescue device according to any one of claims 1-4, characterized in that: the control instruction input terminal is connected to a manual control signal or an automatic control signal.

6. The boost circuit of the elevator emergency rescue device according to claim 5, characterized in that: the manual control signal is switched on and off through a manual switch.

7. The boost circuit of the elevator emergency rescue device according to claim 5, characterized in that: the automatic control signal comes from the MCU control module of the elevator emergency rescue device or other control circuits.

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