CN213505460U - Elevator safety protection system testing device - Google Patents
Elevator safety protection system testing device Download PDFInfo
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- CN213505460U CN213505460U CN202022337525.8U CN202022337525U CN213505460U CN 213505460 U CN213505460 U CN 213505460U CN 202022337525 U CN202022337525 U CN 202022337525U CN 213505460 U CN213505460 U CN 213505460U
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Abstract
The utility model provides an elevator safety protection system testing arrangement, through set up the inverting addition circuit and the inverting amplifier circuit in the signal conditioning circuit, on the one hand, inverting addition circuit's input impedance is extremely low, and each way signal input current gets into the input with the mode of converging, can not cause the electric current flow between each input signal, and the arithmetic accuracy is high; on the other hand, the reversed-phase addition circuit ensures that the polarity of the AC voltage signal after operation is negative or zero, and the amplitude of the AC voltage signal can be adjusted within the sampling range of the CPU chip by only arranging one reversed-phase amplification circuit in the later-stage circuit, so that the circuit is simple in structure and high in sampling precision; the inverse amplification circuit adjusts the amplitude of the-8V-0V alternating voltage signal output by the inverse addition circuit, so that the amplitude is adjusted within the AD sampling range of the CPU chip, thereby reducing the detection error and improving the sampling precision.
Description
Technical Field
The utility model relates to an elevator technical field especially relates to elevator safety protection system testing arrangement.
Background
The traction machine is a power element for dragging the elevator car to move upwards and downwards, and is the key of stable, reliable and safe operation of the elevator. In order to realize accurate closed-loop control of the permanent magnet synchronous traction machine, an elevator traction control system must accurately acquire the current of the rotating speed and the three-phase power of the current motor. At present, a current detection method of a commonly used three-phase power is to obtain a current signal by a method of sampling a resistor, and the current detection method is commonly used for current sampling of a circuit with a small current (1A) or less; the system samples the current of the three-phase four-wire traction machine, the rated current of the traction machine is 20.8A, so the sampling current range is (-25A- +25A), the problem of unmatched current sampling range exists in the method for sampling, the resistance precision is difficult to guarantee, errors and temperature drift are serious, meanwhile, the sampling of the large-current alternating current has certain difficulty in hardware and software implementation, and the power consumption of the system is increased by connecting the sampling resistor in series in the system.
Therefore, in order to solve the problem, the utility model provides an elevator safety protection system testing arrangement, the electric current of sampling range and hauler three-phase electricity matches, and the precision of sampling is high, error and temperature drift are little, and realize easily.
SUMMERY OF THE UTILITY MODEL
In view of this, the utility model provides an elevator safety protection system testing arrangement, the electric current of sampling range and hauler three-phase electricity matches, and the precision of sampling is high, error and temperature drift are little, and realize easily.
The technical scheme of the utility model is realized like this: the utility model provides an elevator safety protection system testing device, which comprises a traction machine, a CPU chip, a Hall current sensor and a signal conditioning circuit, wherein the signal conditioning circuit comprises an inverting addition circuit and an inverting amplifying circuit;
the Hall current sensor collects current signals of three-phase electricity of the tractor and outputs alternating voltage signals, and the alternating voltage signals are input to the analog input end of the CPU chip through the inverted adding circuit and the inverted amplifying circuit which are sequentially connected in series.
On the basis of the above technical solution, preferably, the inverting adder circuit includes a bias voltage, resistors R1-R4, and a first operational amplifier LM 358;
an alternating current voltage signal is input to the inverting input terminal of the first operational amplifier LM358 through the resistor R1, the bias voltage is electrically connected to the inverting input terminal of the first operational amplifier LM358 through the resistor R2, the non-inverting input terminal of the first operational amplifier LM358 is grounded, the resistor R3 is connected in parallel between the inverting input terminal of the first operational amplifier LM358 and the output terminal thereof, and the output terminal of the first operational amplifier LM358 is electrically connected to the input terminal of the inverting amplifier circuit through the resistor R4.
Still further preferably, the inverting amplifying circuit comprises capacitors C10-C12, a resistor R5, a resistor R6, an adjustable resistor R7 and a second operational amplifier LM 324;
the output end of the first operational amplifier LM358 is electrically connected with the inverting input end of the second operational amplifier LM324 through a resistor R4, a capacitor C10 and a resistor R5 which are sequentially connected in series, the non-inverting input end of the second operational amplifier LM324 is grounded through a resistor R6 and a capacitor C11 which are mutually connected in parallel, the adjustable resistor R7 is connected between the inverting input end and the output end of the second operational amplifier LM324 in parallel, and the output end of the second operational amplifier LM324 is electrically connected with the analog input end of the CPU chip through a capacitor C12.
On the basis of the above technical solution, preferably, the signal conditioning circuit further includes a voltage follower;
the voltage follower is connected in series in a line between the hall current sensor and the inverting adder circuit.
Still further preferably, the voltage follower includes a resistor R8 and a third operational amplifier LM 358;
the hall current sensor is electrically connected with the non-inverting input end of the third operational amplifier LM358 through a resistor R8, and the output end of the third operational amplifier LM358 is electrically connected with the inverting input end thereof and the input end of the inverting adder circuit respectively.
On the basis of the technical scheme, the motor rotating speed measuring device preferably further comprises a motor rotating speed measuring circuit;
the motor rotating speed measuring circuit measures the rotating speed of the tractor and converts the rotating speed into an electric signal, and the electric signal is input to the analog input end of the CPU chip.
On the basis of the above technical solution, preferably, the temperature detection circuit is further included;
the temperature detection circuit detects the temperature of the traction machine and converts the temperature into an electric signal, and the electric signal is input to the analog input end of the CPU chip.
The utility model discloses an elevator safety protection system testing arrangement has following beneficial effect for prior art:
(1) the Hall current sensor is used for replacing the existing current signal for measuring the three-phase power of the tractor by using the sampling resistor, so that the Hall current sensor is suitable for collecting a large-current signal, the sampling range is matched with the current of the three-phase power of the tractor, and the problems of error and serious temperature drift caused by the difficulty in precision guarantee of the existing sampling resistor are solved;
(2) by arranging the inverting addition circuit and the inverting amplification circuit in the signal conditioning circuit, on one hand, the input impedance of the inverting addition circuit is extremely low, and each path of signal input current enters the input end in a confluence mode, so that the current flowing among each path of input signals cannot be caused, and the operation precision is high; on the other hand, the inverse addition circuit converts the-4V- +4V alternating voltage signal output by the Hall current sensor into an-8V-0V alternating voltage signal, the inverse addition circuit is used for ensuring that the polarity of the calculated alternating voltage signal is negative or zero, the later-stage circuit only needs to be provided with an inverse amplification circuit to adjust the amplitude of the alternating voltage signal within the sampling range of the CPU chip, the circuit structure is simple, and the sampling precision is high; the inverse amplification circuit adjusts the amplitude of the-8V-0V alternating voltage signal output by the inverse addition circuit, so that the amplitude is adjusted within the AD sampling range of the CPU chip, thereby reducing the detection error and improving the sampling precision;
(3) the voltage follower is arranged in the signal conditioning circuit to play a role of buffering, so that the influence between the Hall current sensor and a post-stage circuit is isolated, the load carrying capacity of the original circuit is improved, the reverse phase addition circuit is convenient to further process an alternating voltage signal output by the Hall current sensor, and the stability of the alternating voltage signal is improved;
(4) the temperature detection circuit and the motor rotating speed measurement circuit are arranged, and the circuit for detecting the three-phase current of the tractor by the Hall current sensor realizes the precise closed-loop control of the permanent magnet synchronous tractor, so that the safety performance of the elevator is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a system structure diagram of the elevator safety protection system testing device of the utility model;
fig. 2 is the circuit diagram of the signal conditioning circuit in the elevator safety protection system testing device of the utility model.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work all belong to the protection scope of the present invention.
As shown in fig. 1, the utility model discloses an elevator safety protection system testing arrangement, it includes hauler, CPU chip, hall current sensor, signal conditioning circuit, motor speed measuring circuit and temperature detect circuit.
The traction machine drags the elevator car to run through a traction steel wire rope, and is a power element of an elevator system.
The Hall current sensor is suitable for collecting a large-current signal, the sampling range is matched with the current of the three-phase power of the tractor, the problems that the accuracy of a sampling resistor is difficult to guarantee by using a sampling resistor in the prior art, and errors and temperature drift are serious are solved, the Hall current sensor collects the current signal of the three-phase power of the tractor and converts and outputs an alternating voltage signal of-4V to +4V to a signal conditioning circuit for processing. Specifically, the hall current sensor collects current signals of three-phase power of the traction machine and outputs alternating-current voltage signals, and the alternating-current voltage signals are input to the analog input end of the CPU chip through an inverting addition circuit and an inverting amplification circuit which are sequentially connected in series.
Although the Hall current sensor can convert a large current of-25A to +25A into a voltage signal of-4V to +4V, the voltage signal does not satisfy the AD sampling range of the CPU chip and surrounds 0 to 3.3V, so that the sampled current signal still has a high error and low sampling accuracy, therefore, the signal conditioning circuit is arranged to process the alternating voltage signal output by the Hall current sensor, and the alternating voltage signal value output by the Hall current sensor is in the AD sampling range of the CPU chip, so that the error is small and the sampling accuracy is high. Preferably, in this embodiment, as shown in fig. 2, the signal conditioning circuit includes a voltage follower, an inverting adder circuit, and an inverting amplifier circuit.
The voltage follower plays a role in buffering, influences between the Hall current sensor and a post-stage circuit are isolated, the load carrying capacity of an original circuit is improved, the reverse phase addition circuit is convenient to further process an alternating voltage signal output by the Hall current sensor, and the stability of the alternating voltage signal is improved. Wherein, the voltage follower is connected in series in a line between the Hall current sensor and the inverting adder circuit. Preferably, in the present embodiment, as shown in fig. 2, the voltage follower includes a resistor R8 and a third operational amplifier LM 358; specifically, an alternating current voltage signal output by the hall current sensor is input to a non-inverting input terminal of the third operational amplifier LM358 through the resistor R8, and an output terminal of the third operational amplifier LM358 is electrically connected to an inverting input terminal thereof and an input terminal of the inverting adder circuit, respectively. As shown in fig. 2, U1 denotes a third operational amplifier LM 358; vi denotes an ac voltage signal output from the hall sensor.
The resistor R8 is a load resistor, so that the third operational amplifier LM358 is prevented from being broken down due to overlarge output voltage of the Hall current sensor; the third operational amplifier LM358 forms a voltage follower which is used as an isolation buffer stage, so that the influence between the Hall current sensor and the inverting addition circuit is isolated, the load bearing capacity of the signal conditioning circuit is improved, the inverting addition circuit can further process the alternating voltage signal output by the Hall current sensor, and the stability of the alternating voltage signal is improved.
On one hand, compared with the in-phase addition circuit, the inverting addition circuit has extremely low input impedance, and each path of signal input current enters the input end in a confluence mode, so that the current flowing among each path of input signals is avoided, and the operation precision is high; on the other hand, an alternating voltage signal of-4V to +4V output by the Hall current sensor is converted into an alternating voltage signal of-8V to 0V, the polarity of the alternating voltage signal after operation is ensured to be negative or zero by using the inverting addition circuit, the amplitude of the alternating voltage signal can be adjusted within the sampling range of the CPU chip by only arranging an inverting amplification circuit in the post-stage circuit, and the circuit is simple in structure and high in sampling precision. Wherein, the inverting addition circuit is connected in series in a line between the voltage follower and the inverting amplification circuit. Preferably, in the present embodiment, as shown in fig. 2, the inverting adder circuit includes a bias voltage, resistors R1-R4, and a first operational amplifier LM 358; specifically, the output terminal of the third operational amplifier LM358 is electrically connected to the inverting input terminal of the first operational amplifier LM358 through a resistor R1, the bias voltage is electrically connected to the inverting input terminal of the first operational amplifier LM358 through a resistor R2, the non-inverting input terminal of the first operational amplifier LM358 is grounded, the resistor R3 is connected in parallel between the inverting input terminal of the first operational amplifier LM358 and the output terminal thereof, and the output terminal of the first operational amplifier LM358 is electrically connected to the input terminal of the inverting amplifier circuit through a resistor R4. As shown in fig. 2, U2 denotes a first operational amplifier LM 358; CA denotes a bias voltage.
The resistor R1 and the resistor R2 are load resistors, and the first operational amplifier LM358 is prevented from being broken down due to overlarge output voltage or reference voltage of the voltage follower; the resistor R3 is a degeneration resistor for reducing the offset voltage error and signal nonlinear distortion of the first operational amplifier LM 358; the resistor R4 is a load resistor, and prevents the output voltage of the first operational amplifier LM358 from being too large to break down the inverting amplifier circuit; the first operational amplifier LM358 forms an inverting adder, is used for superposing and inverting and amplifying the-4V- +4V alternating voltage signal output by the Hall current sensor and the +4V bias voltage to convert the signal into an-8V-0V alternating voltage signal, and simultaneously utilizes negative feedback to reduce the offset voltage error and nonlinear distortion of the signal and improve the sampling precision.
And the reverse-phase amplification circuit adjusts the amplitude of the-8V-0V alternating voltage signal output by the reverse-phase addition circuit, so that the amplitude is adjusted within the AD sampling range of the CPU chip, and the sampling precision is improved. The inverting amplifying circuit is connected in series in a line between the inverting adding circuit and the analog input end of the CPU chip. Preferably, in the embodiment, as shown in fig. 2, the inverting amplifier circuit includes capacitors C10-C12, a resistor R5, a resistor R6, an adjustable resistor R7, and a second operational amplifier LM 324; specifically, the output end of the first operational amplifier LM358 is electrically connected to the inverting input end of the second operational amplifier LM324 through a resistor R4, a capacitor C10 and a resistor R5 which are sequentially connected in series, the non-inverting input end of the second operational amplifier LM324 is grounded through a resistor R6 and a capacitor C11 which are connected in parallel, the adjustable resistor R7 is connected in parallel between the inverting input end and the output end of the second operational amplifier LM324, and the output end of the second operational amplifier LM324 is electrically connected to the analog input end of the CPU chip through a capacitor C12. As shown in fig. 2, U3 denotes a second operational amplifier LM 324; vo _ GPIO1 represents the ac voltage signal output by the inverting amplifier circuit.
The capacitor C10 is a coupling capacitor and is used for filtering out direct-current interference signals in the alternating-current voltage signals output by the inverting and adding circuit; the resistor R5 is a load resistor, and prevents the second operational amplifier LM324 from being broken down due to overlarge output voltage of the inverting adder circuit; the capacitor C11 and the resistor R6 form an RC filter circuit which is used for filtering circuit interference signals and improving the sampling precision; meanwhile, the resistor R6 is used as a balance resistor for eliminating the temperature drift of the second operational amplifier LM 324; the adjustable resistor R7 is a negative feedback resistor and is used for reducing the offset voltage error and signal nonlinear distortion of the second operational amplifier LM 324; the capacitor C12 is a filter capacitor and is used for filtering high-frequency noise signals in the alternating-current voltage signals output by the second operational amplifier LM324, and the sampling precision is further improved; the second operational amplifier LM324 forms a negative feedback operational amplifier and is used for amplifying the alternating voltage value output by the inverting addition circuit in an inverting way, and adjusting the amplitude of the alternating voltage signal output by the inverting addition circuit by adjusting the resistance value of the negative feedback adjustable resistor R7, so that the amplitude is adjusted in the AD sampling range of the CPU chip.
And the motor rotating speed measuring circuit is used for measuring the rotating speed of the tractor, converting the rotating speed into an electric signal and inputting the electric signal into the CPU chip for processing and calculation. Specifically, the motor rotation speed measuring circuit measures the rotation speed of the traction machine and converts the rotation speed into an electric signal, and the electric signal is input to the analog input end of the CPU chip. The present embodiment does not involve an improvement of the circuit configuration of the motor rotation speed measuring circuit, and therefore, the circuit configuration of the motor rotation speed measuring circuit will not be described in detail herein.
And the temperature detection circuit is used for measuring the temperature of the tractor, converting the temperature into an electric signal, inputting the electric signal into the CPU chip for processing and calculation, and realizing the accurate closed-loop control of the permanent magnet synchronous tractor together with the motor rotating speed measurement circuit and the circuit for detecting the three-phase electric current of the tractor by the Hall current sensor. Specifically, the temperature detection circuit detects the temperature of the traction machine and converts the temperature into an electric signal, which is input to the analog input terminal of the CPU chip.
The CPU chip receives the alternating voltage signal output by the inverting amplifying circuit and performs processing calculation; and receiving the electric signals output by the motor rotating speed measuring circuit and the temperature detecting circuit, and processing and calculating the electric signals. Specifically, the inverting amplification circuit, the motor rotating speed measuring circuit and the temperature detection circuit are electrically connected with the analog input end of the CPU chip. In this embodiment, the improvement of the internal algorithm of the CPU chip is not involved, and therefore, the internal algorithm of the CPU chip is not described again here. The model of the CPU chip is not limited in this embodiment, and preferably, TMS320F28232 is selected; the GPIO1 is correspondingly used for representing the analog input end of the CPU chip electrically connected with the inverting amplification circuit; GPIO2 represents the analog input end of CPU chip electrically connected with the motor speed measuring circuit; the GPIO3 corresponds to an analog input terminal of the CPU chip electrically connected to the temperature detection circuit.
The working principle of the embodiment is as follows: the Hall current sensor collects current signals of three-phase electricity of the tractor and converts and outputs-4V- +4V alternating voltage signals to the voltage follower, the voltage follower isolates front and rear stage circuits to output-4V- +4V alternating voltage signals to the inverting addition circuit, the inverting addition circuit converts the-4V- +4V alternating voltage signals into-8V-0V alternating voltage signals and inputs the alternating voltage signals to the inverting amplification circuit, the inverting amplification circuit adjusts and processes the amplitude of the input alternating voltage signals into the amplitude in the AD sampling range of the CPU chip, and the alternating voltage signals after the amplitude adjustment are input to the CPU chip for processing and calculation;
meanwhile, the motor rotating speed measuring circuit measures the rotating speed of the tractor, converts the rotating speed into an electric signal, and inputs the electric signal into the CPU chip for processing and calculation; and the temperature detection circuit is used for measuring the temperature of the tractor, converting the temperature into an electric signal and inputting the electric signal into the CPU chip for processing and calculation, so that the accurate closed-loop control of the permanent magnet synchronous tractor is realized, and the safety performance of the elevator is improved.
The beneficial effect of this embodiment does: the Hall current sensor is used for replacing the existing current signal for measuring the three-phase power of the tractor by using the sampling resistor, so that the Hall current sensor is suitable for collecting a large-current signal, the sampling range is matched with the current of the three-phase power of the tractor, and the problems of error and serious temperature drift caused by the difficulty in precision guarantee of the existing sampling resistor are solved;
through arranging the inverting addition circuit and the inverting amplification circuit in the signal conditioning circuit, on one hand, compared with the in-phase addition circuit, the inverting addition circuit has extremely low input impedance, and each path of signal input current enters the input end in a confluence mode, so that the current flowing among each path of input signals is avoided, and the operation precision is high; on the other hand, the inverse addition circuit converts the-4V- +4V alternating voltage signal output by the Hall current sensor into an-8V-0V alternating voltage signal, the inverse addition circuit is used for ensuring that the polarity of the calculated alternating voltage signal is negative or zero, the later-stage circuit only needs to be provided with an inverse amplification circuit to adjust the amplitude of the alternating voltage signal within the sampling range of the CPU chip, the circuit structure is simple, and the sampling precision is high; the inverse amplification circuit adjusts the amplitude of the-8V-0V alternating voltage signal output by the inverse addition circuit, so that the amplitude is adjusted within the AD sampling range of the CPU chip, thereby reducing the detection error and improving the sampling precision;
the voltage follower is arranged in the signal conditioning circuit to play a role of buffering, so that the influence between the Hall current sensor and a post-stage circuit is isolated, the load carrying capacity of the original circuit is improved, the reverse phase addition circuit is convenient to further process an alternating voltage signal output by the Hall current sensor, and the stability of the alternating voltage signal is improved;
the temperature detection circuit and the motor rotating speed measurement circuit are arranged, and the circuit for detecting the three-phase current of the tractor by the Hall current sensor realizes the precise closed-loop control of the permanent magnet synchronous tractor, so that the safety performance of the elevator is improved.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. Elevator safety protection system testing arrangement, it includes hauler, CPU chip, hall current sensor and signal conditioning circuit, its characterized in that: the signal conditioning circuit comprises an inverting addition circuit and an inverting amplification circuit;
the Hall current sensor collects current signals of three-phase electricity of the tractor and outputs alternating voltage signals, and the alternating voltage signals are input to the analog input end of the CPU chip through the inverted addition circuit and the inverted amplification circuit which are sequentially connected in series.
2. The elevator safety protection system testing device of claim 1, wherein: the inverting adder circuit comprises a bias voltage, resistors R1-R4 and a first operational amplifier LM 358;
the alternating voltage signal is input to the inverting input end of the first operational amplifier LM358 through the resistor R1, the bias voltage is electrically connected with the inverting input end of the first operational amplifier LM358 through the resistor R2, the non-inverting input end of the first operational amplifier LM358 is grounded, the resistor R3 is connected between the inverting input end of the first operational amplifier LM358 and the output end of the first operational amplifier LM358 in parallel, and the output end of the first operational amplifier LM358 is electrically connected with the input end of the inverting amplifying circuit through the resistor R4.
3. The elevator safety protection system testing device of claim 2, wherein: the inverting amplifying circuit comprises capacitors C10-C12, a resistor R5, a resistor R6, an adjustable resistor R7 and a second operational amplifier LM 324;
the output end of the first operational amplifier LM358 is electrically connected with the inverting input end of the second operational amplifier LM324 through a resistor R4, a capacitor C10 and a resistor R5 which are sequentially connected in series, the non-inverting input end of the second operational amplifier LM324 is grounded through a resistor R6 and a capacitor C11 which are mutually connected in parallel, the adjustable resistor R7 is connected between the inverting input end and the output end of the second operational amplifier LM324 in parallel, and the output end of the second operational amplifier LM324 is electrically connected with the analog input end of the CPU chip through a capacitor C12.
4. The elevator safety protection system testing device of claim 1, wherein: the signal conditioning circuit further comprises a voltage follower;
the voltage follower is connected in series in a line between the Hall current sensor and the inverting adder circuit.
5. The elevator safety protection system testing device of claim 4, wherein: the voltage follower comprises a resistor R8 and a third operational amplifier LM 358;
the hall current sensor is electrically connected with the non-inverting input end of the third operational amplifier LM358 through a resistor R8, and the output end of the third operational amplifier LM358 is electrically connected with the inverting input end thereof and the input end of the inverting adder circuit respectively.
6. The elevator safety protection system testing device of claim 1, wherein: the motor rotating speed measuring circuit is also included;
the motor rotating speed measuring circuit measures the rotating speed of the tractor and converts the rotating speed into an electric signal, and the electric signal is input to the analog input end of the CPU chip.
7. The elevator safety protection system testing device of claim 1, wherein: the temperature detection circuit is also included;
the temperature detection circuit detects the temperature of the tractor and converts the temperature into an electric signal, and the electric signal is input to the analog input end of the CPU chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202022337525.8U CN213505460U (en) | 2020-10-19 | 2020-10-19 | Elevator safety protection system testing device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022337525.8U CN213505460U (en) | 2020-10-19 | 2020-10-19 | Elevator safety protection system testing device |
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| CN213505460U true CN213505460U (en) | 2021-06-22 |
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| CN202022337525.8U Active CN213505460U (en) | 2020-10-19 | 2020-10-19 | Elevator safety protection system testing device |
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