CN103423877B - The pulse detection system of inner container of electric water heater and low consumption detection method - Google Patents

Abstract

The invention discloses a pulse pressure detection system and a low-consumption detection method for an inner tank of an electric water heater. Solenoid valve, second solenoid valve, third solenoid valve, electro-hydraulic proportional valve, check valve, first pressure sensing transmitter, second pressure sensing transmitter, pressurized accumulator, pressure-holding energy storage It is composed of a water storage type electric water heater liner, a water tank, a controller and connecting pipelines. Both the pressurized accumulator and the pressure-holding accumulator are gas-filled accumulators. The pulse pressure detection system adopts a double accumulator structure of a pressurized accumulator and a pressure-holding accumulator, which reduces the energy consumption of the system and reduces the impact of the high and low pressure cycle pulse pressure and "back pressure" on the pump output end. Damage; the analog proportional valve PID is used to adjust the water volume injected into the inner tank of the electric water heater, which alleviates the damage to the detection system caused by the "water hammer phenomenon" caused by the switch valve.

Description

Pulse pressure detection system and low consumption detection method of electric water heater inner tank

technical field

The invention belongs to the technical category of pulse pressure detection for electric water heaters, and in particular relates to a pulse pressure detection system and a low-consumption detection method for an inner tank of an electric water heater.

Background technique

The annual sales volume of electric water heaters in my country is about 13 million units. In order to regulate the orderly and healthy development of the electric water heater industry and protect the personal safety of users, the state and industry authorities have successively introduced, formulated and promulgated a series of technical specifications and standards: GB4706 .1 "General Requirements for Safety of Household and Similar Electrical Appliances", GB4706.12 "Special Requirements for Safe Water Storage Water Heaters for Household and Similar Electrical Appliances", GB/T20289-2006 "Water Storage Electric Water Heaters", IEC60379 "Water Heaters Performance Test Method", QB/T 4101-2010 "Water Storage Electric Water Heater Liner". The technical specifications and standards clearly define the rated capacity, heating efficiency, 24-hour inherent energy consumption, hot water output rate, scale hysteresis, temperature hysteresis, safety parameters and technical indicators of electric water heater liner pulse pressure for water storage electric water heaters. . Under the existing technical conditions, the detection devices and detection methods for the first 7 indicators of water storage electric water heaters are quite mature and effective; up to now, only the pulse pressure detection items are still unsatisfactory and need to be improved urgently. The key technical points of the national standard for pulse pressure detection of the inner tank of the water storage electric water heater are as follows:

·Test pressure: 15%～100±5% of rated pressure, adjustable range 0～1Mpa;

Impact counting range: 0~999999 times;

·Working voltage: AC220V;

·Working temperature: 0℃～+50℃;

·Working humidity: 10%～90%RH;

·Impact frequency: 25~60 times/min;

·Working cycle: Stop for 10 minutes after every 10,000 impacts, visually inspect the container for no obvious deformation, and then continue to the next working cycle, the total number of cycles is ≥80,000.

Obviously, the technical difficulty of pulse pressure detection is the high impact frequency index of the water source with adjustable pressure (15%~100±5% of the rated pressure); if the adjustable pressure water source with low impact frequency is used, the detection efficiency will be low, and it will deviate further. The national standard is not advisable.

At present, the current technology to obtain adjustable pressure water source is to use the speed change of frequency conversion motor water pump; motor and water pump have inherent moment of inertia, so the change rate of frequency conversion motor water pump speed cannot reach the expected pressure change rate of adjustable pressure water source at all. That is, the impact frequency of pulse pressure detection is limited by the rate of change that can be achieved by the speed of the variable frequency motor water pump; at present, both inspection agencies and manufacturers have proposed a solution of "high-voltage variable frequency water pump + pipeline switching" (see the patent "Electric Water Heater Container Pulse Pressure Life Test Device", Patent No. ZL201120240605.X; Wang Donghao, Water Heater Tank Pressure Test Device, Home Appliance Technology [J], 2007.11). The basic principle of the "high-voltage frequency conversion water pump + pipeline switching" solution is: during the whole process of pulse pressure detection, the frequency conversion motor and water pump controlled by the frequency converter are always in a high-speed state; The process is realized by the opening and closing of the valve on the corresponding pipeline, that is, through the pipeline switching of the pulse pressure detection system; the process of pressurization in the pulse pressure detection and the high pressure holding process after pressurization still depends on the pipeline realized by valve opening and closing. Switching; since the variable frequency motor water pump is always in a high-speed state, it eliminates the time required for the variable frequency motor water pump to change from low/high speed to high/low speed corresponding to the process of adding/relieving pressure—meeting the expectations of the adjustable pressure water source of the pulse pressure detection system rate of pressure change. The solution of "high-voltage variable-frequency water pump + pipeline switching" is feasible, but there are many defects that need to be improved; the defects, causes and improvement measures of the solution of "high-voltage frequency-variable water pump + pipeline switching" are listed as follows:

1. The pulse pressure detection system consumes a lot of energy. The impact main cycle process of pulse pressure detection involves: pressurization, high pressure holding process after pressurization, pressure relief, low pressure holding process after pressure relief; only the pressurization process of the impact main cycle process needs the input energy of frequency conversion motor water pump , the input energy of the variable frequency motor water pump to maintain the high/low pressure holding process is negligible, and it is only used to compensate the leakage loss of the container to be tested and related pipelines. The pressure relief process is the energy release of the high-pressure water in the container to be tested. The variable-frequency motor water pump in the solution of "high-voltage variable-frequency water pump + pipeline switching" is always in a high-speed state, and the input energy of the variable-frequency motor water pump in the process of high/low pressure holding and pressure relief is in a state of empty consumption, which leads to excessive energy consumption of the pulse pressure detection system . Taking the pulse pressure detection system that inspection institutions and production enterprises always have as an example, the power of the frequency conversion motor water pump is about 4000W, and the pulse pressure detection of the tank of the water storage electric water heater (the frequency is 50 times/min, the total number of pulse cycles = 80000) consumes Electric energy: (80000÷50)÷60×4 + (80000÷10000)×10÷60×4=112 (degrees); in view of the fact that the pressurization process only accounts for a small part of the time slice of the main impact cycle, the absolute power of 112 degrees Most of it goes to waste. On the premise of ensuring the stable and reliable operation of the pulse pressure detection system, if the input energy of the frequency conversion motor water pump in the process of high/low pressure holding and pressure relief can be fully utilized, the excessive energy consumption of the pulse pressure detection system will be reduced.

2. The negative impact of "back pressure" and "water hammer" on the life of the pulse pressure detection system. In the solution of "high-voltage frequency conversion water pump + pipeline switching", the output end of the frequency conversion motor water pump needs to withstand the pulse pressure of high and low pressure cycles, and the "back pressure" at the output end will shorten the life of the water pump (pressure detection system). On the other hand, the pressure relief in the pulse pressure detection, the low-pressure pressure holding process after pressure relief, and the high-pressure pressure holding process after pressurization and pressurization are all realized by the opening and closing of switch valves and multi-pipe switching; valves and multi-pipelines The switching of pipelines will cause hydraulic impact to produce water hammer. The "water hammer phenomenon" will cause damage to electric water heaters, components, pipelines and connectors of the detection system; in addition, pipeline switching is limited due to the limited number of pipelines , the detection range of the detection system will also be limited. If the water pressure at the output end of the variable frequency motor water pump can remain basically unchanged, the negative factor of "back pressure" will be effectively overcome; if the hydraulic buffer device can be installed and the number of pipeline switching can be reduced, it is expected to reduce the damage of "water hammer phenomenon" ; In addition, the water injected into the tank of the water storage electric water heater is controlled by the analog quantity instead of the switch quantity, which will greatly extend the detection range of the detection system.

3. The qualitative time of pressurization, high pressure holding, pressure relief and low pressure holding in the shock main cycle is not conducive to the consistency of test results.

Aiming at the defects of the pulse pressure detection system and detection method of the water storage type electric water heater liner, the present invention proposes improvement measures one by one: first, the output end of the frequency conversion motor water pump is installed with an air-filled accumulator, and the pressure is relieved and the high/low pressure is maintained. During the process, the accumulator absorbs the energy output by the frequency conversion motor water pump, and during the pressurization process, the accumulator and the frequency conversion motor water pump jointly output energy; it not only reduces the energy consumption of the detection system, but also eliminates the "back pressure" at the output end of the frequency conversion motor water pump. Secondly, the analog proportional valve PID is used to adjust the amount of water injected into the inner tank of the electric water heater; it not only alleviates the harm of "water hammer phenomenon", but also extends the detection range of the detection system. Third, quantifying the time of pressurization, high-pressure holding, pressure relief and low-pressure holding in the main shock cycle will help improve the consistency of the detection results of the pulse pressure detection system.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a pulse pressure detection system and a low-consumption detection method for the inner tank of an electric water heater.

The pulse pressure detection system of the storage type electric water heater includes a frequency conversion motor water pump, an overflow valve, an overflow valve with an additional remote control port connected in series with an overflow electromagnet, the first solenoid valve, the second solenoid valve, the third solenoid valve, Electro-hydraulic proportional valve, check valve, first pressure sensing transmitter, second pressure sensing transmitter, pressurized accumulator, pressure-holding accumulator, water storage type electric water heater liner, water tank, control The pressurized accumulator and the pressure-holding accumulator are all gas-filled accumulators;

The controller includes CPU224XP DC/DC/DC module, the input and output module of the CPU module, the mold input and output module of the CPU module, the power supply NES-75-24 module, the communication module of the CPU module, and the touch screen MT8070iH module;

The water inlet of the frequency conversion motor water pump is connected to the water tank through the water inlet pipe, the first water outlet of the frequency conversion motor water pump is connected to the water tank through the overflow valve, and the second water outlet of the frequency conversion motor water pump is connected to the overflow through a check valve and an additional remote control port in series. The overflow valve of the flow electromagnet is connected with the water tank, and the third water outlet of the variable frequency motor water pump passes through the check valve, the pressurized accumulator, the first pressure sensor transmitter, the first solenoid valve, and the electro-hydraulic proportional valve in sequence. , the second pressure sensor transmitter, the tank of the water storage electric water heater, the third solenoid valve connected to the water tank, the water inlet of the second solenoid valve connected to the pipeline between the first solenoid valve and the electro-hydraulic proportional valve, The water outlet of the second electromagnetic valve is connected with the pressure maintaining accumulator;

The CPU224XP DC/DC/DC module of the controller performs data transmission with the touch screen MT8070iH module through the communication module. The 4-way switching value DO ₁ , DO ₂ , DO ₃ , DO ₄ are respectively connected with the overflow valve, the first solenoid valve, the second solenoid valve, and the third solenoid valve connected in series with the overflow electromagnet at the additional remote control port, and the mold is inserted into the mold. The two mold inlets of the outlet module are respectively connected to the AI ₁ and AI ₂ analog quantities output by the first pressure sensor transmitter and the second pressure sensor transmitter, and the analog control quantity output by the mold outlet of the mold-in and mold-out module AO is connected with electro-hydraulic proportional valve.

The low-consumption detection method of the pulse pressure detection system includes the detection preparation process, the impact main cycle process and the 10-minute pressure holding process after the main impact cycle of 10,000 times;

Test preparation process: Input the test pressure P ₀ on the touch screen human-computer interaction interface, the total number of impact main cycles N of pulse pressure detection, the frequency f ₀ of the main impact cycle, that is, the main impact cycle T ₀ , the working cycle T, and the interval of the working cycle Time, pressurization t ₁ / high pressure holding t ₂ / pressure relief t ₃ / low pressure holding t ₄ process time in the main impact cycle,

Determine the operating pressure threshold P ₁ of the relief valve, and input the operating pressure threshold P ₂ of the relief valve on the touch screen human-computer interaction interface, P ₁ >P ₂ >P ₀ ,

Close the third solenoid valve, open the first solenoid valve, the second solenoid valve, and the electro-hydraulic proportional valve, fill the tank of the water storage electric water heater with water, close the electro-hydraulic proportional valve, start the variable frequency motor water pump, when the pressure analog AI ₁ When >P ₂ , the switching value DO ₁ of the controller opens the overflow valve, when the outlet pressure of the variable frequency motor water pump is greater than P ₁ , the overflow valve overflows, the pressurized accumulator and the pressure-holding accumulator complete energy storage, and enter the impact The conditions for the pressurization process of the main circulation process are ready;

The main impact cycle process consists of pressurization, high pressure holding, pressure relief and low pressure holding:

Pressurization process - the frequency conversion motor water pump is running, close the third solenoid valve, open the first solenoid valve and the second solenoid valve, according to the deviation P ₀ -AI ₂ , PID controls the opening of the electro-hydraulic proportional valve, so that AI ₂ = P ₀ , if t ₁ <0.15T ₀ or t ₁ >0.2T ₀ , then reduce or increase the frequency of the variable frequency motor water pump at the end of the main impact cycle, otherwise the frequency of the variable frequency motor water pump remains unchanged.

·High pressure holding process--the variable frequency motor water pump is running, the first solenoid valve is closed, and the opening of the electro-hydraulic proportional valve is controlled by PID according to the deviation P ₀ -AI ₂ , and the pressure holding accumulator is output to the inner tank of the water storage electric water heater energy, the variable frequency motor water pump outputs energy to the pressurized accumulator until t ₁ +t ₂ =0.5T ₀ ,

·Pressure relief process--the frequency conversion motor water pump is running, close the second solenoid valve and electro-hydraulic proportional valve, open the third solenoid valve, when AI ₂ =0.15P ₀ , close the third solenoid valve, and the frequency conversion motor water pump will pressurize and store energy device output energy,

·Low pressure maintenance process--the frequency conversion motor water pump is running, open the second solenoid valve and electro-hydraulic proportional valve, according to the deviation of 0.15P ₀ -AI ₂ , PID controls the opening of the electro-hydraulic proportional valve, and the pressure-maintaining accumulator to the water storage The tank of the electric water heater outputs energy, and the water pump of the variable frequency motor outputs energy to the pressurized accumulator until t ₃ +t ₄ =0.5T ₀ ;

10-minute pressure-holding process after 10,000 impacts on the main cycle: first complete the pressurization process of the impacting main cycle, close the third solenoid valve, reduce the frequency of the variable frequency motor water pump, open the first solenoid valve, the second solenoid valve and the electro-hydraulic proportional The valve, according to the deviation P ₀ -AI ₂ , PID controls the opening of the electro-hydraulic proportional valve, the pressurized accumulator and the pressure-holding accumulator output energy to the inner tank of the water storage electric water heater so that AI ₂ =P ₀ , time delay 10min;

· If AI ₂ < P ₀ and there is no problem with the connecting pipeline, and the tank of the water storage electric water heater is unqualified, the inspection will be terminated.

Visual inspection of the water storage type electric water heater liner is obviously deformed, if it is unqualified, the inspection will be suspended.

·Visual inspection of the storage type electric water heater has no obvious deformation, and the number of main shock cycles is less than the total number of shocks N, then a new work cycle will be executed.

·Visual inspection of the inner tank of the water storage electric water heater has no obvious deformation, and the number of main impact cycles = the total number of impacts N, if it is qualified, the test will be terminated.

  Compared with the background technology, the present invention has the beneficial effects of:

With the help of dual accumulators for adding/holding pressure, the input energy of the frequency conversion motor water pump in the process of high/low pressure holding and pressure relief is fully utilized, reducing the excessive energy consumption of the pulse pressure detection system;

With the help of adding/holding double accumulators, the high and low pressure cycle pulse pressure on the output end of the variable frequency motor water pump is reduced, and the damage to the water pump caused by the "back pressure" at the output end of the water pump is reduced;

The analog proportional valve PID is used to adjust the amount of water injected into the inner tank of the electric water heater, which alleviates the damage to the detection system caused by the "water hammer phenomenon" caused by the switch valve, and extends the detection range of the detection system.

Description of drawings

Figure 1 is a structural diagram of the pulse pressure detection system for the tank of the water storage electric water heater;

Fig. 2 (a) is the flow chart of the low-consumption detection method of the pulse pressure detection system;

Figure 2(b) is the detection system preparation process of the pulse pressure detection system;

Fig. 2 (c) is the impact main circulation process of the pulse pressure detection system;

Figure 2(d) is the 10-minute pressure-holding process of the pulse pressure detection system.

Detailed ways

As shown in Figure 1, the pulse pressure detection system of the tank of the water storage electric water heater includes a variable frequency motor water pump 10, an overflow valve 20, an additional remote control port connected in series with an overflow electromagnet overflow valve 21, a first electromagnetic valve 22, Second solenoid valve 23, third solenoid valve 24, electro-hydraulic proportional valve 25, check valve 26, first pressure sensing transmitter 31, second pressure sensing transmitter 32, pressurized accumulator 41, The pressure-maintaining accumulator 42 is composed of a storage-type electric water heater liner 50, a water tank 60, a controller 70 and connecting pipelines. Both the pressurized accumulator and the pressure-maintaining accumulator are gas-filled accumulators;

The controller 70 includes a CPU224XP DC/DC/DC module 71, a built-in input and output module 72 of the CPU module, a mold-in and mold-out module 73 of the CPU module, a power supply NES-75-24 module 74, and a built-in CPU module Communication module 75, touch screen MT8070iH module 76;

The water inlet of the frequency conversion motor water pump 10 is connected to the water tank 60 through the water inlet pipe, the first water outlet of the frequency conversion motor water pump 10 is connected to the water tank 60 through the overflow valve 20, and the second water outlet of the frequency conversion motor water pump 10 passes through the check valve 26 The overflow valve 21 connected in series with the overflow electromagnet with the additional remote control port is connected with the water tank 60, and the third water outlet of the frequency conversion motor water pump 10 passes through the check valve 26, the pressurized accumulator 41, the first pressure sensor variable Transmitter 31, first electromagnetic valve 22, electro-hydraulic proportional valve 25, second pressure sensor transmitter 32, water storage type electric water heater liner 50, third electromagnetic valve 24 is connected with water tank 60, second electromagnetic valve 23 The water inlet of the first solenoid valve 22 is connected to the pipeline between the electro-hydraulic proportional valve 25, and the water outlet of the second solenoid valve 23 is connected with the pressure maintaining accumulator 42;

The CPU224XP DC/DC/DC module 71 of the controller 70 performs data transmission with the touch screen MT8070iH module 76 through the communication module 75. The 4-way switching values DO ₁ , DO ₂ , DO ₃ , and DO ₄ output by the output module 72 are respectively connected to the additional remote control port in series with the overflow valve 21 of the overflow electromagnet, the first solenoid valve 22, the second solenoid valve 23, The third solenoid valve 24 is connected, and the two mold inlets of the mold-in and mold-out module 73 are respectively connected to the AI ₁ and AI ₂ analog quantities output by the first pressure sensor transmitter 31 and the second pressure sensor transmitter 32, The analog control quantity AO output by the mold outlet of the mold-in mold-out module 73 is connected with the electro-hydraulic proportional valve 25 .

As shown in Figure 2, the low-consumption detection method of the pulse pressure detection system includes the detection preparation process, the main impact cycle process and the 10-minute pressure holding process after the main impact cycle for 10,000 times;

Test preparation process: Input the test pressure P ₀ (default value 1MPa), the total number of impact main cycles N (default value 80,000 times) of the pulse pressure test, and the main impact cycle frequency f ₀ (default value 60 times/min), that is, the shock main cycle period T ₀ (default value 1S), work cycle T (default value 10000 shock main cycle time = 10000S), work cycle interval time (default value 10min), shock Pressurization t ₁ /high pressure holding t ₂ /pressure relief t ₃ /low pressure holding t ₄ process time in the main cycle (default value 0.15T ₀ ≤t ₁ ≤0.2T ₀ , t ₁ +t ₂ =0.5 T ₀ , t ₃ ≤0.2T ₀ , t ₃ +t ₄ =0.5T ₀ ),

Determine the operating pressure threshold P ₁ of the overflow valve 20 and manually set it, and input the operating pressure threshold P ₂ of the overflow valve 21 on the touch screen human-computer interaction interface, P ₁ >P ₂ >P ₀ ,

Close the third solenoid valve 24, open the first solenoid valve 22, the second solenoid valve 23, and the electro-hydraulic proportional valve 25, fill the tank 50 of the water storage electric water heater with water, close the electro-hydraulic proportional valve 25, and start the variable frequency motor water pump 10 . When the pressure analog quantity AI ₁ >P ₂ , the switching value DO ₁ of the controller 70 opens the overflow valve 21. When the outlet pressure of the variable frequency motor water pump 10 is greater than P ₁ , the overflow valve 20 overflows and pressurizes the accumulator 41 Complete the energy storage with the pressure-holding accumulator 42, and the conditions for entering the pressurization process of the impact main circulation process are ready;

The main impact cycle process consists of pressurization, high pressure holding, pressure relief and low pressure holding:

Pressurization process - the frequency conversion motor water pump 10 is running, the third solenoid valve 24 is closed, the first solenoid valve 22 and the second solenoid valve 23 are opened, and the opening of the electro-hydraulic proportional valve 25 is controlled by PID according to the deviation P ₀ -AI ₂ , Make AI ₂ =P ₀ , if t ₁ <0.15T ₀ or t ₁ >0.2T ₀ , then lower or increase the frequency of the variable frequency motor water pump 10 at the end of the main impact cycle, otherwise the frequency of the variable frequency motor water pump 10 will not Change,

·High pressure holding process--the variable frequency motor water pump 10 is running, the first solenoid valve 22 is closed, the opening of the electro-hydraulic proportional valve 25 is controlled by PID according to the deviation P ₀ -AI ₂ , and the pressure holding accumulator 42 is turned to the water storage type electric valve. The water heater liner 50 outputs energy, and the variable frequency motor water pump 10 outputs energy to the pressurized accumulator 41 until t ₁ +t ₂ =0.5T ₀ ,

·Pressure relief process--the frequency conversion motor water pump 10 is running, close the second solenoid valve 23 and electro-hydraulic proportional valve 25, open the third solenoid valve 24, when AI ₂ =0.15P ₀ , close the third solenoid valve 24, frequency conversion motor water pump 10 output energy to the pressurized accumulator 41,

·Low pressure maintenance process--the frequency conversion motor water pump 10 is running, the second solenoid valve 23 and the electro-hydraulic proportional valve 25 are opened, and according to the deviation of 0.15P ₀ -AI ₂ , the PID controls the opening of the electro-hydraulic proportional valve 25, pressure maintenance and energy storage The device 42 outputs energy to the tank 50 of the water storage type electric water heater, and the variable frequency motor water pump 10 outputs energy to the pressurized accumulator 41 until t ₃ +t ₄ =0.5T ₀ ;

The 10-minute pressure-holding process after 10,000 impacts on the main cycle: first complete the pressurization process of the impact on the main cycle, close the third solenoid valve 24, reduce the frequency of the variable frequency motor water pump 10, and open the first solenoid valve 22 and the second solenoid valve 23 And the electro-hydraulic proportional valve 25, according to the deviation P ₀ -AI ₂ , PID controls the opening of the electro-hydraulic proportional valve 25, the pressurized accumulator 41 and the pressure-holding accumulator 42 output energy to the water storage type electric water heater inner tank 50 Make AI ₂ =P ₀ and delay for 10 minutes;

· If AI ₂ < P ₀ and there is no problem with the connecting pipeline, and the tank of the water storage electric water heater is unqualified, the inspection will be terminated.

Visual inspection of the water storage type electric water heater liner is obviously deformed, if it is unqualified, the inspection will be suspended.

·Visual inspection of the storage type electric water heater has no obvious deformation, and the number of main shock cycles is less than the total number of shocks N, then a new work cycle will be executed.

·Visual inspection of the inner tank of the water storage electric water heater has no obvious deformation, and the number of main impact cycles = the total number of impacts N, if it is qualified, the test will be terminated.

Claims (2)

1. the pulse detection system of a water storage type liner of water heater, it is characterized in that system comprises variable-frequency motor water pump (10), overflow valve (20), the overflow valve (21) of additional remote mouth serial connection overflow electromagnet, first magnetic valve (22), second magnetic valve (23), 3rd magnetic valve (24), electro-hydraulic proportional valve (25), check-valves (26), first pressure sensing transmitter (31), second pressure sensing transmitter (32), pressurization accumulator (41), pressurize accumulator (42), water storage type liner of water heater (50), water tank (60), controller (70) and connecting line composition, pressurization accumulator and pressurize accumulator are inflatable accumulator,

The mould that the input and output module (72) that controller (70) comprises CPU224XP DC/DC/DC module (71), CPU module carries, CPU module carry enters communication module (75), the touch-screen MT8070iH module (76) that mould goes out module (73), power supply NES-75-24 module (74), CPU module carry;

The water inlet of variable-frequency motor water pump (10) is connected with water tank (60) by water inlet pipe, the first via delivery port of variable-frequency motor water pump (10) is connected with water tank (60) through overflow valve (20), second road delivery port of variable-frequency motor water pump (10) is through check-valves (26), the overflow valve (21) of additional remote mouth serial connection overflow electromagnet is connected with water tank (60), 3rd road delivery port of variable-frequency motor water pump (10) is successively by check-valves (26), pressurization accumulator (41), first pressure sensing transmitter (31), first magnetic valve (22), electro-hydraulic proportional valve (25), second pressure sensing transmitter (32), water storage type liner of water heater (50), 3rd magnetic valve (24) is connected with water tank (60), the water inlet of the second magnetic valve (23) is connected on the pipeline between the first magnetic valve (22) and electro-hydraulic proportional valve (25), the delivery port of the second magnetic valve (23) is connected with pressurize accumulator (42),

The CPU224XP DC/DC/DC module (71) of controller (70) carries out data transmission by communication module (75) and touch-screen MT8070iH module (76), civil power one tunnel access variable-frequency motor, another road of civil power access power supply NES-75-24 module (74), the 4 way switch amount DO that input and output module (72) exports ₁, DO ₂, DO ₃, DO ₄be connected in series the overflow valve (21) of overflow electromagnet respectively with additional remote mouth, the first magnetic valve (22), the second magnetic valve (23), the 3rd magnetic valve (24) be connected, mould enters the AI that two mould entrances access the first pressure sensing transmitter (31) respectively, the second pressure sensing transmitter (32) exports that mould goes out module (73) ₁and AI ₂analog quantity, mould enter mould go out module (73) mould outlet export analogue enlargement amount AO be connected with electro-hydraulic proportional valve (25).

2. use a low consumption detection method for pulse detection system as claimed in claim 1, it is characterized in that comprising and detect 10 minutes pressurize flow processs after preparing flow process, impact major cycle flow process and ten thousand Secondary Shocks major cycles;

Detect and prepare flow process: on touch-screen human-computer interaction interface, input test pressure P ₀, pulse detect impact major cycle total degree N, impact main loop rate f ₀namely major cycle cycle T is impacted ₀, work period T, the interval time of work period, the pressurization t impacted in the major cycle cycle ₁/ high pressure pressurize t ₂/ release t ₃/ low-pressure pressure retaining t ₄process time,

Determine the operating pressure threshold values P of overflow valve (20) ₁, touch-screen human-computer interaction interface inputs the operating pressure threshold values P of overflow valve (21) ₂, P ₁>P ₂>P ₀,

Close the 3rd magnetic valve (24), open the first magnetic valve (22), the second magnetic valve (23), electro-hydraulic proportional valve (25), water storage type liner of water heater (50) fills water, closes electro-hydraulic proportional valve (25), starts variable-frequency motor water pump (10), as pressure mould analog quantity AI ₁>P ₂the switching value DO of Time Controller (70) ₁open overflow valve (21), be greater than P when the outlet pressure of variable-frequency motor water pump (10) ₁time overflow valve (20) overflow, pressurization accumulator (41) and pressurize accumulator (42) complete accumulation of energy, the condition entering impact major cycle flow process pressure process is ready;

Impact major cycle flow process by pressurizeing, high pressure pressurize, release and low-pressure pressure retaining process form:

Pressure process--variable-frequency motor water pump (10) runs, and closes the 3rd magnetic valve (24), opens the first magnetic valve (22) and the second magnetic valve (23), according to deviation P ₀-AI ₂, PID control electro-hydraulic proportional valve (25) aperture, make AI ₂=P ₀if, t ₁<0.15T ₀or t ₁>0.2T ₀, then impact major cycle flow process at the end of turn down or heighten the frequency of variable-frequency motor water pump (10) otherwise the frequency of variable-frequency motor water pump (10) is constant,

High pressure pressure maintaining period--variable-frequency motor water pump (10) runs, and closes the first magnetic valve (22), according to deviation P ₀-AI ₂, aperture, the pressurize accumulator (42) of PID control electro-hydraulic proportional valve (25) export energy to water storage type liner of water heater (50), and variable-frequency motor water pump (10) exports energy, until t to pressurization accumulator (41) ₁+ t ₂=0.5T ₀,

Stress-relief process--variable-frequency motor water pump (10) runs, and closes the second magnetic valve (23) and electro-hydraulic proportional valve (25), opens the 3rd magnetic valve (24), work as AI ₂=0.15P ₀time close the 3rd magnetic valve (24), variable-frequency motor water pump (10) to pressurization accumulator (41) export energy,

Low-pressure pressure retaining process--variable-frequency motor water pump (10) runs, and opens the second magnetic valve (23) and electro-hydraulic proportional valve (25), according to deviation 0.15P ₀-AI ₂, aperture, the pressurize accumulator (42) of PID control electro-hydraulic proportional valve (25) export energy to water storage type liner of water heater (50), and variable-frequency motor water pump (10) exports energy, until t to pressurization accumulator (41) ₃+ t ₄=0.5T ₀;

10 minutes pressurize flow processs after ten thousand Secondary Shocks major cycles: first complete the pressure process of impacting major cycle flow process, close the 3rd magnetic valve (24), reduce the frequency of variable-frequency motor water pump (10), open the first magnetic valve (22) second magnetic valve (23) and electro-hydraulic proportional valve (25), according to deviation P ₀-AI ₂, PID control electro-hydraulic proportional valve (25) aperture, pressurization accumulator (41) and pressurize accumulator (42) to water storage type liner of water heater (50) output energy make AI ₂=P ₀, time delay 10min;

AI ₂<P ₀and connecting line no problem, water storage type liner of water heater are defective, stop to detect,

Range estimation water storage type liner of water heater be obviously out of shape, defective, stop detect,

Range estimation water storage type liner of water heater impacts total N then perform the new work period without obviously distortion, impact major cycle number <,

Range estimation water storage type liner of water heater without obviously distortion, to impact major cycle number=impact total N then qualified, stop to detect.