CN106226632B - Aging test system and method for variable frequency drive of motor - Google Patents
Aging test system and method for variable frequency drive of motor Download PDFInfo
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- CN106226632B CN106226632B CN201610804676.5A CN201610804676A CN106226632B CN 106226632 B CN106226632 B CN 106226632B CN 201610804676 A CN201610804676 A CN 201610804676A CN 106226632 B CN106226632 B CN 106226632B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D21/00—Measuring or testing not otherwise provided for
- G01D21/02—Measuring two or more variables by means not covered by a single other subclass
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/34—Testing dynamo-electric machines
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- General Physics & Mathematics (AREA)
- Inverter Devices (AREA)
- Testing Electric Properties And Detecting Electric Faults (AREA)
Abstract
The motor variable frequency drive aging test system comprises a simulation motor module, a direct current load and a grid-connected inverter, wherein the simulation motor module is electrically connected with a variable frequency drive to be subjected to aging test, the simulation motor module comprises a rectification filter module, and three input ends of the rectification filter module are connected with three-phase PWM output ends of the variable frequency drive; the input end of the direct current load is connected with two direct current output ends of the rectifying and filtering module, the input end of the grid-connected inverter is connected with the output end of the direct current load, and the output end of the grid-connected inverter is connected with the commercial power alternating current power grid; the control module is electrically connected with the variable frequency driver, the rectifying and filtering module and the direct current load respectively. The aging test system is simple in structure and can be suitable for variable frequency drives with different specifications; three-phase power output by the variable frequency driver is provided for a load and a grid-connected inverter through rectification and filtering, so that the motor running environment is simulated, 80% of electric energy is recovered to a commercial power grid, and the energy-saving effect is remarkable.
Description
Technical Field
The invention relates to the field of ageing test equipment, in particular to a motor variable frequency drive ageing test system and a motor variable frequency drive ageing test method.
Background
At present, the aging test of the variable frequency drive is usually carried out by two modes of resistor aging and generator energy-saving feedback aging. The resistor ageing converts electric energy into heat energy, the energy dissipation is large, and when the variable frequency drivers with different specifications are aged, the resistors with different specifications are required to be replaced, the process is complicated, and more manpower is required to be consumed; the energy-saving feedback type aging of the generator is realized by connecting a variable frequency driver with a motor, converting electric energy into mechanical energy by the motor, driving the generator to operate by the motor, converting the mechanical energy into electric energy by the generator, and feeding the electric energy back to a power grid by a grid-connected inverter. The mode has the advantages of more energy conversion times, limited energy saving effect, complex equipment structure connection and large occupied space.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a frequency conversion driver aging test system with a simple structure and remarkable energy-saving effect.
In order to achieve the above purpose, the technical scheme provided by the invention is as follows: the motor variable frequency drive aging test system comprises a simulation motor module, a direct current load and a grid-connected inverter, wherein the simulation motor module is electrically connected with a variable frequency drive to be subjected to aging test, the simulation motor module comprises a rectification filter module, and three input ends of the rectification filter module are connected with three-phase PWM output ends of the variable frequency drive; the input end of the direct current load is connected with two direct current output ends of the rectifying and filtering module, the input end of the grid-connected inverter is connected with the output end of the direct current load, and the output end of the grid-connected inverter is connected with a commercial power alternating current power grid; the control module is electrically connected with the variable frequency driver, the rectifying and filtering module and the direct current load respectively.
Further describing the scheme, the rectification filter module converts the three-phase PWM output by the variable frequency driver into a single direct current signal and transmits the single direct current signal to a direct current load for pulling.
The scheme is further described, the rectifying and filtering module comprises a rectifying and filtering circuit and a singlechip serving as a control module, and the rectifying and filtering circuit consists of a capacitor, an inductor and a diode.
The scheme is further described, the intelligent monitoring system further comprises a PC and a monitoring system, wherein the monitoring system is computer monitoring software, and the PC is electrically connected with the singlechip through an RS485 cable.
Further describing the scheme, the grid-connected inverter is a high-frequency PWM rectification inverter circuit.
Further describing the scheme, the direct current load is a Flyback circuit.
In order to achieve the above purpose, the invention also provides a testing method of the aging testing system of the variable frequency drive of the motor, which connects the variable frequency drive with an alternating current power grid and an analog motor module, and executes the following steps to perform the aging test of the variable frequency drive:
step one, starting electrifying, and initializing an analog motor module;
step two, detecting whether the analog motor module receives a control signal of a PC (personal computer), if so, carrying out step three, and if not, repeating the step two, wherein the control signal of the PC is a group of continuously-changed signals;
step three, the analog motor module converts control signals of the PC computer into current, voltage and power parameters, and sends the current, voltage and power parameter signals to the direct current load and the variable frequency driver;
step four, the analog motor module collects output voltage, current and rotating speed parameter information of the variable frequency driver, detects whether the voltage and the current are normal or not, if yes, step five is carried out, and if not, step six is carried out;
step five, the analog motor module transmits the voltage, current and rotating speed parameter information of the variable frequency driver back to the PC computer for storage, and returns to the step four for cyclic execution; if the control signals of a group of PC computers which continuously change are executed, the cycle is ended in advance in the step, and the aging test result is transmitted back to the PC computers for storage;
and step six, the analog motor module sends a shutdown signal to the variable frequency driver and the direct current load, sends error information to the PC computer, and stops the aging test.
The invention has the beneficial effects that: the aging test system has simple structure, convenient maintenance and small occupied area; the intelligent control can be applied to variable frequency drives with different specifications, and is beneficial to popularization; three-phase power output by the variable frequency driver is provided for a load and a grid-connected inverter through rectification and filtering, so that the motor running environment is simulated, 80% of electric energy is recovered to a commercial power grid, and the energy-saving effect is remarkable.
Drawings
Fig. 1 is a schematic block diagram of the present invention.
Fig. 2 is a schematic flow chart of the present invention.
In the figure: 1. a variable frequency drive; 2. a simulation motor module; 3. a direct current load; 4. grid-connected inverter; 5. and a control module.
Detailed Description
A specific embodiment of the present invention will be described with reference to fig. 1 to 2.
The motor variable frequency drive aging test system comprises a simulation motor module 2, a direct current load 3 and a grid-connected inverter 4, wherein the simulation motor module 2 is electrically connected with a variable frequency drive 1 to be subjected to aging test, the simulation motor module 2 comprises a rectification filter module, and three input ends of the rectification filter module are connected with three-phase PWM output ends of the variable frequency drive 1; the input end of the direct current load 3 is connected with two direct current output ends of the rectifying and filtering module, the input end of the grid-connected inverter 4 is connected with the output end of the direct current load 3, and the output end of the grid-connected inverter 4 is connected with a commercial power alternating current power grid; the control module 5 is electrically connected with the variable frequency driver 1, the rectifying and filtering module and the direct current load 3 respectively.
The rectification filtering module converts the three-phase PWM output by the variable frequency driver 1 into a single direct current signal and transmits the single direct current signal to the direct current load 3 for load pulling.
The rectification filter module comprises a rectification filter circuit and a singlechip serving as a control module 5, wherein the singlechip is respectively and electrically connected with the direct current load 3 and the variable frequency driver 1 so as to control the pulling load parameter of the direct current load 3, the current, the voltage and the power electrical parameters output by the variable frequency driver 1, the rectification filter circuit consists of a capacitor, an inductor and a diode, and the rectification filter circuit has an MCU control function. The analog motor module 2 has overvoltage, overcurrent, overpower and over-temperature protection, and the analog motor module 2 can change the three-phase PWM output by the variable frequency driver 1 into a single direct current signal.
The system also comprises a PC and a monitoring system, wherein the monitoring system is computer monitoring software, and the PC is electrically connected with the singlechip through an RS485 cable. The monitoring system can realize the control of all the aged variable frequency drives 1, including the functions of aging temperature, aging time, aging on-off impact time sequence, automatic fault shutdown, abnormal alarm and the like. The analog motor module 2 samples the voltage, current and frequency signals output by the variable frequency driver 1 in real time, converts the signals into rotating speed and power signals and transmits the rotating speed and power signals back to the computer monitoring software, and the computer monitoring software displays the rotating speed and power signals on a computer.
The grid-connected inverter 4 is a high-frequency PWM rectifying inverter circuit having voltage and phase tracking capability.
The direct current load 3 is a Flyback circuit capable of controlling input current and power, namely a single-ended Flyback DC-DC converter.
As shown in fig. 2, a test method of a motor variable frequency drive 1 aging test system connects a variable frequency drive 1 with an ac power grid and an analog motor module 2, and performs the following steps to perform the variable frequency drive 1 aging test:
step one, starting electrifying, and initializing the simulation motor module 2;
step two, detecting whether the analog motor module 2 receives a control signal of a PC computer, if so, performing step three, and if not, repeating the step two; the control signal of the PC computer is a group of continuously-changing signals;
step three, the analog motor module 2 converts control signals of the PC computer into current, voltage and power parameters, and sends the current, voltage and power parameter signals to the direct current load 3 and the variable frequency driver 1;
step four, the analog motor module 2 collects the output voltage, current and rotating speed parameter information of the variable frequency driver 1, detects whether the voltage and the current are normal, if yes, carries out step five, and if not, carries out step six;
step five, the simulation motor module 2 transmits the voltage, current and rotation speed parameter information of the variable frequency driver 1 back to the PC computer for storage, and returns to the step four for cyclic execution; if the control signals of a group of PC computers which continuously change are executed, the cycle is ended in advance in the step, and the aging test result is transmitted back to the PC computers for storage;
step six, the simulation motor module 2 sends a shutdown signal to the variable frequency drive 1 and the direct current load 3, and sends error information to the PC computer to stop the aging test.
When the power grid system works, the variable frequency driver 1 is connected into a commercial power grid, output three-phase power is connected to the rectification filtering module, the rectification filtering module converts high-frequency three-phase PWM rectification filtering into direct current and outputs the direct current to the direct current load 3, the direct current load 3 controls load current and power, and finally the grid-connected inverter 4 feeds 80% of energy back to the commercial power grid. The analog motor module 2 receives signals from the monitoring system about motor types, power, current, voltage and the like which are accessed in use of the variable frequency drive 1, the control module of the analog motor module 2 converts the rotating speed, frequency and phase conversion of the motor and sends the signals to the variable frequency drive 1, the output power of the variable frequency drive 1 is changed, and meanwhile, the control module of the analog motor module 2 converts the signals of load power, current and voltage which are needed by the direct current load 3 and sends the signals to the direct current load 3 for carrying; in the whole process, the monitoring system collects and stores working parameters of the variable frequency drive 1, the rectifying and filtering module and the direct current load 3, judges whether the whole aging test process of the variable frequency drive 1 is qualified or not, and displays the information through monitoring software in a computer.
The above description should not be taken as limiting the scope of the invention, and any modifications, equivalent variations and modifications made to the above embodiments according to the technical spirit of the invention still fall within the scope of the technical solutions of the invention.
Claims (4)
1. A test method of a motor variable frequency drive aging test system is characterized in that the test system comprises a simulation motor module, a direct current load and a grid-connected inverter;
the simulation motor module is electrically connected to the variable frequency driver to be subjected to aging test and comprises a rectification filter module, and three input ends of the rectification filter module are connected to three-phase PWM output ends of the variable frequency driver; the input end of the direct current load is connected with two direct current output ends of the rectifying and filtering module, the input end of the grid-connected inverter is connected with the output end of the direct current load, and the output end of the grid-connected inverter is connected with a commercial power alternating current power grid; the control module is electrically connected with the variable frequency driver, the rectifying and filtering module and the direct current load respectively;
the rectification filter module comprises a rectification filter circuit and a singlechip as a control module, and the rectification filter circuit consists of a capacitor, an inductor and a diode;
the test system also comprises a PC computer and a monitoring system, wherein the monitoring system is computer monitoring software, and the PC computer is electrically connected with the singlechip through an RS485 cable;
the testing method comprises the steps of connecting the variable frequency drive with an alternating current power grid and an analog motor module, and executing the following steps to perform aging test of the variable frequency drive:
step one, starting electrifying, and initializing an analog motor module;
step two, detecting whether the analog motor module receives a control signal of a PC (personal computer), if so, carrying out step three, and if not, repeating the step two, wherein the control signal of the PC is a group of continuously-changed signals;
step three, the analog motor module converts control signals of the PC computer into current, voltage and power parameters, and sends the current, voltage and power parameter signals to the direct current load and the variable frequency driver;
step four, the analog motor module collects output voltage, current and rotating speed parameter information of the variable frequency driver, detects whether the voltage and the current are normal or not, if yes, step five is carried out, and if not, step six is carried out;
step five, the analog motor module transmits the voltage, current and rotating speed parameter information of the variable frequency driver back to the PC computer for storage, and returns to the step four for cyclic execution; if the control signals of a group of PC computers which continuously change are executed, the cycle is ended in advance in the step, and the aging test result is transmitted back to the PC computers for storage;
and step six, the analog motor module sends a shutdown signal to the variable frequency driver and the direct current load, sends error information to the PC computer, and stops the aging test.
2. The test method of the aging test system of the variable frequency drive of the motor according to claim 1, wherein the rectifying and filtering module converts the three-phase PWM output by the variable frequency drive into a single direct current signal and transmits the single direct current signal to the direct current load for pulling.
3. The method for testing a motor variable frequency drive aging test system according to claim 1, wherein the grid-connected inverter is a high-frequency PWM rectifying inverter circuit.
4. The method for testing a motor variable frequency drive aging test system according to claim 1, wherein the dc load is a Flyback circuit.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610804676.5A CN106226632B (en) | 2016-09-06 | 2016-09-06 | Aging test system and method for variable frequency drive of motor |
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| CN201610804676.5A CN106226632B (en) | 2016-09-06 | 2016-09-06 | Aging test system and method for variable frequency drive of motor |
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| CN106226632A CN106226632A (en) | 2016-12-14 |
| CN106226632B true CN106226632B (en) | 2023-10-20 |
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| CN106526484A (en) * | 2016-12-15 | 2017-03-22 | 东莞市冠达自动化设备有限公司 | Energy-saving aging system of direct current motor driver and aging method thereof |
| CN108333508A (en) * | 2017-12-22 | 2018-07-27 | 苏州恒美电子科技股份有限公司 | Power control system for electromechanical testing |
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| CN112994114A (en) * | 2021-04-29 | 2021-06-18 | 深圳市杰能科技有限公司 | Aging feedback system and method for energy-saving test of frequency converter |
| CN113985167A (en) * | 2021-10-20 | 2022-01-28 | 天水电气传动研究所集团有限公司 | Feedback type power aging test experimental system for high-power direct-current conversion device |
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